U.S. patent application number 16/378621 was filed with the patent office on 2019-08-01 for seat backrest.
This patent application is currently assigned to TS TECH CO., LTD.. The applicant listed for this patent is TS TECH CO., LTD.. Invention is credited to Shuichi SHIMIZU.
Application Number | 20190232831 16/378621 |
Document ID | / |
Family ID | 50434880 |
Filed Date | 2019-08-01 |
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United States Patent
Application |
20190232831 |
Kind Code |
A1 |
SHIMIZU; Shuichi |
August 1, 2019 |
SEAT BACKREST
Abstract
A seat backrest includes right and left side frame segments, a
pressure receiving member disposed between the side frame segments
movably in a front-back direction, and a cushion pad covering the
front of the side frame segments and pressure receiving member. The
pressure receiving member includes a main body part, and extending
parts extending laterally from both sides of the main body part.
The cushion pad includes a back receiving part covering the front
of the main body part, and bank parts disposed on both sides of the
back receiving part, protruding forward from both sides, and
covering the front of the extending parts and side frame segments.
A recess is formed at an area, facing a corresponding extending
part of the extending parts, of a rear surface of each bank
part.
Inventors: |
SHIMIZU; Shuichi; (Tochigi,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TS TECH CO., LTD. |
Asaka-shi |
|
JP |
|
|
Assignee: |
TS TECH CO., LTD.
Asaka-shi
JP
|
Family ID: |
50434880 |
Appl. No.: |
16/378621 |
Filed: |
April 9, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15606703 |
May 26, 2017 |
10300816 |
|
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16378621 |
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14432772 |
Apr 1, 2015 |
9694723 |
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PCT/JP2013/076474 |
Sep 30, 2013 |
|
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15606703 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60N 2/42745 20130101;
B60N 2/68 20130101; B60N 2/72 20130101; B60N 2/665 20150401; B60N
2/7094 20130101; B60N 2/66 20130101; B60N 2/6671 20150401; B60N
2/4228 20130101; B60N 2/666 20150401 |
International
Class: |
B60N 2/42 20060101
B60N002/42; B60N 2/66 20060101 B60N002/66; B60N 2/68 20060101
B60N002/68; B60N 2/427 20060101 B60N002/427; B60N 2/72 20060101
B60N002/72; B60N 2/70 20060101 B60N002/70 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 1, 2012 |
JP |
2012-219610 |
Claims
1. A seat backrest comprising: left and right side frame segments
disposed in parallel in the right-left direction; a pressure
receiving member disposed between the side frame segments, the
pressure receiving member being movable in a front-back direction;
an airbag module mounted on a side frame segment of the side frame
segments; a cushion pad covering front surfaces of the side frame
segments and a front surface of the pressure receiving member; a
skin covering the cushion pad; a reinforcing cloth attaching member
attached to the side frame segment; and a reinforcing cloth
stretching from a back of the skin to the reinforcing cloth
attaching member via a periphery of the airbag module, wherein the
pressure receiving member includes: a main body part; and right and
left extending parts extending rightward and leftward from right
and left sides of the main body part, wherein the reinforcing cloth
attaching member is provided at a position deviating from a
trajectory of each extending part, the trajectory being drawn at a
time of front-back moving of the pressure receiving member.
2. The seat backrest according to claim 1, wherein the right and
left extending parts respectively extend front rightward and front
leftward from right and left sides of the main body part, and front
edges of the right and left extending parts are positioned forward
with respect to a part of the side frame segments which has a same
height with the front edge.
3. The seat backrest according to claim 1, wherein the reinforcing
cloth attaching member is disposed anterior to the front edge of an
extending part of the extending parts.
4. The seat backrest according to claim 1, wherein each extending
part inclines upward toward the back, and the reinforcing cloth
attaching member is disposed above or below a lower edge of the
extending part.
5. The seat backrest according to claim 1, wherein the reinforcing
cloth attaching member is disposed either above or below the
extending part or both above and below the extending part.
6. The seat backrest according to claim 1, wherein a bead is formed
on each extending part, a vertical position of the reinforcing
cloth attaching member aligns with a vertical position of each
extending part, and the reinforcing cloth attaching member is
disposed above or below the bead.
7. The seat backrest according to claim 1, wherein a bead is formed
in each extending part, the reinforcing cloth attaching member is a
wire rod including a support and a pair of upper and lower arms,
the support extending vertically in front of one of the side frame
segments and over which the reinforcing cloth is to be covered, and
the pair of upper and lower arms bending backward at a top end and
a bottom end of the support, extending in front of and inside of
the side frame segment, and having rear ends attached to the side
frame segment; and the arms are disposed above or below the
bead.
8. The seat backrest according to claim 1, wherein a protrusion
protruding forward is formed in the side frame segment, and the
reinforcing cloth attaching member is disposed above or below a
most forward protruding portion of the protrusion.
9. The seat backrest according to claim 1, further comprising a
side support member attached to a front end of a side frame segment
of the side frame segments, wherein the side support member
includes a vertical section and a bent section, the vertical
section vertically extending away from a front surface of the side
frame segment, and the bent section being bent backward at an end
of the vertical section and fixed to a front end of the side
support member, and wherein, in lateral view, a front edge of the
extending part is disposed in an area between the front surface of
the side frame segment and the vertical section.
10. The seat backrest according to claim 1, wherein a protrusion
protruding forward is formed in the side frame segment, the
reinforcing cloth attaching member is a clip, and the reinforcing
cloth attaching member is disposed below a most forward protruding
portion of the protrusion.
Description
[0001] This is a continuation application of application Ser. No.
15/606,703, filed May 26, 2017, which is a continuation application
of application Ser. No. 14/432,772 filed Apr. 1, 2015, which is a
371 of International Application No. PCT/JP2013/076474 filed Sep.
30, 2013, which claims priority to JP 2012-219610 filed Oct. 1,
2012. The disclosures of the prior applications are hereby
incorporated by reference herein in their entirety.
TECHNICAL FIELD
[0002] The present invention relates to a seat backrest.
BACKGROUND ART
[0003] The backrest of a vehicle seat is provided with a headrest
on its top. The headrest supports the head of an occupant from the
rear. At a rear-end collision by another vehicle, the headrest
receives the head of the occupant to cushion the impact on the neck
region of the occupant.
[0004] While an occupant is seated on a vehicle seat, the occupant
often leans the upper body against the backrest with the head
slightly spaced apart from the headrest. At a rear-end collision by
another vehicle, the head of the occupant is received by the
headrest while slightly inclined backward and then tilted forward
by the reaction of the impact force. This impairs the advantageous
effects of the headrest, i.e., shock-absorbing advantageous effects
on the neck of the occupant.
[0005] Technology has been developed that allows the headrest to
receive the head of an occupant rapidly by letting the upper body
of the occupant deeply sink into the backrest of a vehicle seat at
a rear-end collision by another vehicle (See PTL 1). More
specifically, a pressure receiving member is provided within the
frame of a backrest such that the pressure receiving member is
movable in the front-back direction. At least the front surface of
the frame and the pressure receiving member is covered with a
cushion pad (See PTL 1). In the technology disclosed in PTL 1, at a
rear-end collision by another vehicle, the upper body of the
occupant sinks into the cushion pad and the central portion of the
cushion pad and the pressure receiving member retreat, thus
allowing the headrest to rapidly receive the head of the
occupant.
[0006] In the technology disclosed in PTL 2, an upper coupling wire
is bridging the upper portions of the left and right side frames of
the backrest. The lower coupling wire is bridging the lower
portions of the left and right side frames. A plate-like pressure
receiving member is coupled to the left and right side frames via
the coupling wires and disposed between the left and right side
frames to support the backrest pad from the rear.
[0007] In the technology disclosed in PTL 3, multiple springs are
fixed to the backrest frame such that they extend across the
lateral width. A support material is mounted in front of the
springs. An airbag is mounted in front of the support material. The
inflation or deflation of the airbag changes the shape of a pad
disposed in front of the airbag. This operation can adjust the
lumbar support position of an occupant.
[0008] The side frames of the backrest disclosed in PTL 1 are each
provided with a reinforcing cloth attaching member (reinforcing
cloth fixing bracket). The reinforcing cloth attaching members are
disposed around the pressure receiving member. The reinforcing
cloth attaching members are connected with a reinforcing cloth to
control the direction of deploying the airbag.
[0009] In the technology disclosed in PTL 4, a hook and an airbag
module are mounted on the side frames of the backrest. A
reinforcing cloth is stretched from the hook to a skin seam via the
vicinity of the airbag module. At the inflation of an airbag in the
airbag module, the airbag is guided to the seam by the reinforcing
cloth. Further pulling of the reinforcing cloth by the inflating
airbag causes the skin seam to be torn and the air bag to protrude
from the torn seam (See PTL 4).
[0010] In the technology disclosed in PTL 5, a vibration generator
that generates vibrations is disposed within the backrest. The
vibration of the seat back by the vibration generator can provide
the occupant with massage and awakening effects.
PRIOR ART LITERATURES
Patent Literatures
[0011] PTL 1: Japanese Unexamined Patent Application Publication
No. 2012-136056
[0012] PTL 2: Japanese Unexamined Patent Application Publication
No. 2010-179754
[0013] PTL 3: Japanese Unexamined Patent Application Publication
No. 2001-150988
[0014] PTL 4: Japanese Patent No. 4452860
[0015] PTL 5: Japanese Unexamined Utility Model Application
Publication No. 61-196741
DISCLOSURE OF INVENTION
Problems to be Solved by the Invention
[0016] Bank parts are provided on the right and left of the front
of the cushion pad of a backrest. The bank parts protrude forward
more than the central portion of the back receiving part. The bank
parts enhance the ability to hold an occupant and receive the right
and left sides (mainly, shoulders, shoulder blades, franks and
upper arms) of the upper body of the occupant. At a rear-end
collision by another vehicle, the bank parts receives the right and
left sides of the upper body of the occupant. The central portion
of the back receiving part and the pressure receiving member
retreat and then the bank parts are pressed backward and compressed
by the right and left sides of the upper body of the occupant.
Thus, the bank parts may reduce the effect of sinking the upper
body of the occupant backward.
[0017] An object of the present invention, which has been made to
solve the problem, is to prevent the bank parts from reducing the
effect of sinking the upper body of the occupant backward.
Means for Solving Problems
[0018] In order to achieve the above-described object, a seat
backrest according to the present invention includes: right and
left side frame segments disposed in parallel in a right-left
direction; a pressure receiving member disposed between the side
frame segments, the pressure receiving member being movable in a
front-back direction; and a cushion pad covering front surfaces of
the side frame segments and a front surface of the pressure
receiving member, wherein the pressure receiving member includes: a
main body part; and right and left extending parts extending
rightward and leftward from right and left sides of the main body
part, wherein the cushion pad includes: aback receiving part
covering a front surface of the main body part, and bank parts
disposed on right and left sides of the back receiving part,
protruding forward from right and left sides of a front surface of
the back receiving part, and covering front surfaces of the
extending parts and the front surfaces of the side frame segments,
and wherein a recess is formed at an area of a rear surface of each
bank part, the area facing a corresponding extending part of the
extending parts.
Effects of the Invention
[0019] According to the present invention, recesses are formed on
the rear surfaces of the bank parts to provide a space into which
the recess areas of the bank parts retreat and bend. At a rear-end
collision by other vehicle, the recess areas of the bank parts
retreat and bend although the sides of the upper body of an
occupant are received by the bank parts. This can prevent the bank
parts from reducing the backward sinking of the upper body of the
occupant.
[0020] When an occupant leans against the backrest, the recess
areas of the bank parts are received by the extending parts of the
pressure receiving member. Although the recesses formed on the rear
surfaces of the bank parts reduce the holding ability of the bank
parts themselves, the extending parts can compensate for the
reduced holding ability.
BRIEF DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a side view of a seat according to a first
embodiment of the present invention.
[0022] FIG. 2 is an exploded perspective view of a backrest
according to the first embodiment of the present invention.
[0023] FIG. 3 is a front view of a frame of the backrest according
to the first embodiment of the present invention.
[0024] FIG. 4 is a perspective view of a side frame of the backrest
according to the first embodiment of the present invention.
[0025] FIG. 5 is a front view of a cushion pad of the backrest
according to the first embodiment of the present invention.
[0026] FIG. 6 is a front view of the backrest according to the
first embodiment of the present invention.
[0027] FIG. 7 is a transverse sectional view taken along line
VII-VII in FIG. 6, viewed in the direction of arrows.
[0028] FIG. 8 is a partial cross-sectional back view that
illustrates the back of the frame of the backrest and a partial
longitudinal section of a cushion pad and a skin.
[0029] FIG. 9 is a transverse sectional view taken along VII-VII in
FIG. 6 for describing the behavior of each part of the
backrest.
[0030] FIG. 10 is a perspective view of a seat according to a
second embodiment of the present invention.
[0031] FIG. 11 is an exploded perspective view of a backrest
according to the second embodiment of the present invention.
[0032] FIG. 12 is a perspective view of a side frame of the
backrest according to the second embodiment of the present
invention.
[0033] FIG. 13 is a side view of the backrest according to the
second embodiment of the present invention.
[0034] FIG. 14 is a transverse cross-sectional view of the backrest
according to the second embodiment of the present invention.
[0035] FIG. 15 is a partial cross-sectional back view that
illustrates the back of the frame of the backrest and a partial
longitudinal section of a cushion pad and a skin.
[0036] FIG. 16 is a transverse sectional view of the backrest for
describing a point modified from the backrest shown in FIG. 14.
[0037] FIG. 17 is a transverse sectional view of the front end of
the side frame of the backrest and a hook according to the second
embodiment of the present invention.
[0038] FIG. 18 is a perspective view of a side frame of a backrest
according to a first modification of the second embodiment of the
present invention.
[0039] FIG. 19 is an exploded perspective view of a backrest
according to a third modification of the second embodiment of the
present invention.
[0040] FIG. 20 is a perspective view of a side frame of the
backrest according to the third modification of the second
embodiment of the present invention.
[0041] FIG. 21 is a side view of the backrest according to the
third modification of the second embodiment of the present
invention.
[0042] FIG. 22 is a transverse sectional view of the backrest
according to the third modification of the second embodiment of the
present invention.
[0043] FIG. 23 is a perspective view of a seat according to a third
embodiment of the present invention.
[0044] FIG. 24 is a perspective view of a frame in the seat
according to the third embodiment of the present invention.
[0045] FIG. 25 is a front view of a backrest according to the third
embodiment of the present invention and a frame in the
backrest.
[0046] FIG. 26 is a cross sectional view taken along line XXVI-XXVI
in FIG. 25.
[0047] FIG. 27 is a front view of a seat back frame according to a
first modification of the third embodiment of the present
invention.
[0048] FIG. 28 is a perspective view of a seat according to a
fourth embodiment of the present invention.
[0049] FIG. 29 is a perspective view of a frame in the seat
according to the fourth embodiment of the present invention.
[0050] FIG. 30 is a front view of aback rest and a frame according
to the fourth embodiment of the present invention.
[0051] FIG. 31 is a cross sectional view taken along line XXXI-XXXI
in FIG. 30.
[0052] FIG. 32 is a perspective view of a frame of a backrest
according to a first modification of the fourth embodiment of the
present invention.
[0053] FIG. 33 is a front view of the backrest according to the
first modification of the fourth embodiment of the present
invention and the frame in the backrest.
[0054] FIG. 34 is a cross sectional view taken along line
XXXIV-XXXIV shown in FIG. 33.
[0055] FIG. 35 is a perspective view of a seat according to a fifth
embodiment of the present invention.
[0056] FIG. 36 is a rear view of a frame in a backrest according to
the fifth embodiment of the present invention.
[0057] FIG. 37 is a rear perspective view of the lower portion of a
main body part of a pressure receiving member disposed within the
frame of the backrest according to the fifth embodiment of the
present invention and a vibration generator.
[0058] FIG. 38 is a rear view of a frame in a backrest according to
a first modification of the fifth embodiment of the present
invention.
[0059] FIG. 39 is a rear perspective view of an extending part of a
pressure receiving member disposed within the frame of the backrest
according to the first modification of the fifth embodiment of the
present invention and a vibration generator.
[0060] FIG. 40 is a perspective view of a seat according to a sixth
embodiment of the present invention.
[0061] FIG. 41 is a perspective view of a seat frame in the seat
according to the sixth embodiment of the present invention.
[0062] FIG. 42 is a front view of a backrest according to the sixth
embodiment of the present invention and a frame in the
backrest.
[0063] FIG. 43 is a cross sectional view taken along line
XXXXIII-XXXXIII in FIG. 42.
[0064] FIG. 44 is an enlarged sectional view of a backrest
according to a first modification of the sixth embodiment of the
present invention.
[0065] FIG. 45 is an enlarged sectional view of a backrest for
describing a change from the backrest shown in FIG. 44.
[0066] FIG. 46 is an enlarged sectional view of a backrest
according to a second modification of the sixth embodiment of the
present invention.
[0067] FIG. 47 is a perspective view of a frame of a backrest
according to a third modification of the sixth embodiment of the
present invention.
[0068] FIG. 48 is a front view of the frame of the backrest
according to the third modification of the sixth embodiment of the
present invention.
[0069] FIG. 49 is an enlarged sectional view of the backrest
according to the third modification of the sixth embodiment of the
present invention.
[0070] FIG. 50 is a front perspective view of a frame of a backrest
according to a seventh embodiment of the present invention.
[0071] FIG. 51 is a front perspective view of a lumbar support
plate of the backrest according to the seventh embodiment of the
present invention.
[0072] FIG. 52 is a rear perspective view of the lumbar support
plate of the backrest according to the seventh embodiment of the
present invention.
[0073] FIG. 53 is a rear perspective view of an assembly of the
lumbar support plate of the backrest according to the seventh
embodiment assembled and a pressure receiving member.
[0074] FIG. 54 is a front perspective view of a pressure receiving
member of the backrest according to the seventh embodiment of the
present invention.
[0075] FIG. 55 is a front perspective view of a frame of a backrest
according to an eighth embodiment of the present invention.
[0076] FIG. 56 is a front perspective view of a lumbar support
plate of the backrest according to the eighth embodiment of the
present invention.
[0077] FIG. 57 is a rear perspective view of the lumbar support
plate of the backrest according to the eighth embodiment of the
present invention.
[0078] FIG. 58 is a front view of an assembly of the lumbar support
plate of the backrest according to the eighth embodiment of the
present invention and a pressure receiving member.
[0079] FIG. 59 is a rear perspective view of the assembly of the
lumbar support plate of the backrest according to the eighth
embodiment assembled and the pressure receiving member.
EMBODIMENTS TO CARRY OUT THE INVENTION
[0080] Embodiments of the present invention will now be described
with reference to the accompanying drawings. Although the following
embodiments include various limitations that are technically
preferred in the practice of the present invention, the scope of
the present invention should not be limited to the embodiments or
illustrated examples.
[0081] In the following description, right and left sides are
determined by the back and front sides of the seat 1. That is, the
right and left sides depend on the perspective of a person seated
in the seat 1.
First Embodiment
[0082] FIG. 1 is a side view of a seat 1. FIG. 2 is a perspective
view of a frame of the seat 1.
[0083] The seat 1 is a vehicle seat. In particular, the seat 1 is a
vehicle seat provided in the interior of an automobile. The seat 1,
which is an automotive seat, is used as driver's seat or
passenger's seat.
[0084] The seat 1 includes slide rails 2, a bottom seat (seat
cushion) 3, a backrest (seat back) 4, a recliner mechanism 5 and a
headrest 6.
[0085] The headrest 6 is mounted on the top end of the backrest 4.
The backrest 4 has the bottom end coupled to the rear end of the
bottom seat 3 via the recliner mechanism 5. The backrest 4 stands
on the rear end of the bottom seat 3. The recliner mechanism 5
allows the backrest 4 to tilt in the front-back direction with
respect to the bottom seat 3 around the bottom end of the backrest
4. The recliner mechanism 5 locks the backrest 4 to the bottom seat
3 to stop tilting back of the backrest 4 and unlocks the backrest 4
to urge the backrest 4 forward.
[0086] When an occupant is seated on the seat 1, the hip and the
thighs of the occupant are supported from the bottom by the bottom
seat 3 and the upper body of the occupant is supported from the
back by the backrest 4. The head of the occupant is supported from
the back by the headrest 6. At a rear-end collision by a vehicle
running back (with the seat 1 mounted) against another vehicle or
an obstacle or at a rear-end collision by another vehicle, a
backward load is applied from the upper body of the occupant to the
backrest 4 (details will be given in detail later). Even in such a
case, the seat 1 can sink the upper body of the occupant into the
backrest 4.
[0087] The bottom seat 3 includes a bottom seat frame 30, a cushion
pad 38 and a skin 39. The frame 30 is within the bottom seat 3 and
constitutes part of the bottom seat 3. Viewed from the above, the
frame 30 is a skeleton covered with the cushion pad 38. The cushion
pad 38 is covered with the skin 39. The skin 39 is made, for
example, of artificial leather or cloth. The frame 30 is mounted on
the slide rails 2, which enables the bottom seat 3 to move in the
front-back direction.
[0088] The backrest 4 includes a backrest frame 40, a pressure
receiving member 41, a cross member 42, an upper wire rod 43, a
lower wire rod 44, a cushion pad (backrest pad) 48 and a skin 49.
The backrest frame 40 is within the backrest 4 and constitutes part
of the backrest 4. Viewed from the front, the backrest frame 40 is
a skeleton. The pressure receiving member 41 is disposed inside the
backrest frame 40. The backrest frame 40 and the pressure receiving
member 41 are covered with the cushion pad 48. The cushion pad 48
is covered with the skin 49. The skin 49 is made, for example, of
artificial leather or cloth. The backrest frame 40 has the bottom
end coupled to the recliner mechanism 5. The recliner mechanism 5
is coupled to the rear end of the frame 30. The recliner mechanism
5 makes the backrest frame 40 movable in the front-back direction.
The frame 30 in the bottom seat 3, the backrest frame 40 in the
backrest 4, and the recliner mechanism 5 are assembled into a seat
frame.
[0089] With reference to FIGS. 2 and 3, the backrest frame 40 of
the backrest 4 will now be described in detail. FIG. 2 is an
exploded perspective view of the backrest 4. FIG. 3 is the front
view of the backrest frame 40 of the backrest 4.
[0090] The backrest frame 40 includes an upper frame segment
(horizontal pipe segment) 40a, side frame segments 40b, and a lower
frame segment 40c. The side frame segments 40b are disposed on the
right and left respectively in parallel at a certain interval and
extend vertically. The upper frame segment 40a extends in the
right-left direction, with the left end of the upper frame segment
40a coupled to the top end of the left side frame segment 40b and
the right end of the upper frame segment 40a coupled to the top end
of the right side frame segment 40b. Support brackets 91 for
mounting the headrest 6 are fixed on the upper frame segment 40a by
welding. The lower frame segment 40c extends in the right-left
direction, with the left end of the lower frame segment 40c coupled
to the bottom end of the left side frame segment 40b and the right
end of the lower frame segment 40c coupled to the bottom end of the
right side frame segment 40b.
[0091] The side frame segments 40b each include vertical pipe
segments 40b1 and main body parts 40b2 of the side frame segments.
The right and left vertical pipe segments 40b1 are bent downward
from the right and left ends of the upper frame segment 40a and are
integrated with the upper frame segment 40a. A pipe is bent into a
gate shape (for example, reversed U shape, C shape, or angular
U-shape) to form the vertical pipe segments 40b1 and the upper
frame segment 40a. The main body parts 40b2 of the side frame
segments are made of a pressed metal sheet. The main body parts
40b2 of the side frame segments each have a substantially U shaped
cross section along the right-left and front-back directions. The
main body parts 40b2 of the side frame segments face each other and
are disposed along the right-left direction at a certain interval.
The right and left main body parts 40b2 of the side frame segments
are welded to the bottom ends of the right and left vertical pipe
segments 40b1, respectively, and extend therefrom. The lower frame
segment 40c is made of a metal sheet. The lower frame segment 40c
has right and left ends coupled to the bottom ends of the main body
parts 40b2 of the side frame segments. The lower portions of the
main body parts 40b2 of the side frame segments each have a
protrusion 40b3 protruding forward.
[0092] A cross member 42 is disposed between the side frame
segments 40b. The cross member 42 is a meandrous rod in front view.
The cross member 42 has right and left ends coupled to the vertical
pipe segments 40b1 by welding.
[0093] With reference to FIGS. 2 to 4, the pressure receiving
member 41, the upper wire rod (upper coupling wire rod) 43 and the
lower wire rod (lower coupling wire rod) 44 will now be described.
FIG. 4 is a perspective view of the side frame segment 40b.
[0094] The pressure receiving member 41 is coupled to the backrest
frame 40 with the upper wire rod 43 and the lower wire rod 44 such
that the pressure receiving member 41 can retreat with respect to
the main body parts 40b2 of the side frame segments. In other
words, the pressure receiving member 41 partially blocks an opening
surrounded by the backrest frame 40 and is movable in the
front-back direction by the upper wire (rod) 43 and the lower wire
(rod) 44.
[0095] The upper wire rod (spring wire) 43 and the lower wire rod
(spring wire) 44 couple the pressure receiving member 41 to the
backrest frame 40.
[0096] The upper wire rod 43 bridges the side frame segments 40b
below the cross member 42. The upper wire rod 43 has right and left
ends coupled to the vertical pipe segments 40b1. More specifically,
mounts (supporting tongues) 43a are attached to the vertical pipe
segments 40b1, respectively, by welding. The right and left ends of
the upper wire rod 43 are hooked to the mounts 43a, thereby
coupling the right and left ends of the upper wire rod 43 to the
vertical pipe segments 40b1 via the mounts 43a. The mounts 43a are
attached to the vertical pipe segments 40b1 at positions avoiding
the front ends of the vertical pipe segments 40b1 and within the
range from the front ends of the vertical pipe segments 40b1 inside
of the backrest frame 40. The upper wire rod 43 has a meandrous
shape in front view. The upper wire rod 43 has flexibility and
resilience. The cross member 42 has much higher rigidity than the
upper wire rod 43.
[0097] The lower wire rod 44 bridges the main body parts 40b2 of
the side frame segments below the upper wire rod 43. More
specifically, the lower wire rod 44 has a right end coupled to a
right swing member (link member) 45a. The lower wire rod 44 has a
left end thereof coupled to a left swing member 45a. These swing
members 45a are coupled to the main body parts 40b2 of the left and
right side frame segments such that the swing members 45a can move
in the front-back direction. The swing members 45a are each
provided with stoppers 45b and 45c in front and rear thereof. The
stoppers 45b and 45c are fixed to the main body part 40b2 of each
side frame segment. Each swing member 45a is coupled to one end of
a tension spring 45d. The tension spring 45d is coupled to the side
frame segment 40b diagonally upward to the front of the swing
member 45a. The tension spring 45d pulls the swing member 45a
forward. The swing member 45a comes into contact with the front
stopper 45b. This allows the stopper 45b to receive the tensile
load of the tension spring 45d. The application of a backward load
exceeding a predetermined value to the lower wire rod 44 and the
pressure receiving member 41 causes the swing members 45a to move
back against the tensile load of the tension springs 45d and brings
the swing members 45a into contact with the rear stoppers 45c,
thereby stopping the swing members 45a.
[0098] The lower wire 44 has a meandrous shape in front view. The
lower wire 44 has flexibility and resilience. The cross member 42
has much higher rigidity than that of the lower wire 44.
[0099] The pressure receiving member 41 is supported by the upper
wire rod 43 and the lower wire rod 44 and disposed between the side
frame segments 40b such that the pressure receiving member 41 is
suspended by the upper wire rod 43 and the lower wire rod 44. The
pressure receiving member 41 is disposed below the cross member
42.
[0100] The pressure receiving member 41 is a plate made of resin.
More specifically, the pressure receiving member 41 is made of
synthetic resin, such as polypropylene, and has a predetermined
strength enough to support a seated person. Multiple claws
(engaging claws) 41c and 41d are provided on the rear surface of
the pressure receiving member 41. The upper wire rod 43 is hooked
to the claws 41c. The lower wire rod 44 is hooked to the claws 41d.
This configuration allows the pressure receiving member 41 to be
supported by the upper wire rod 43 and the lower wire rod 44 while
the pressure receiving member 41 stands. The upper wire rod 43 is
engaged with the claws 41c formed on the upper rear surface of the
pressure receiving member 41 to couple the upper portion of the
pressure receiving member 41 to the left and right side frame
segments 40b. The lower wire rod 44 is engaged with the claws 41d
formed on the lower rear surface of the pressure receiving member
41 to couple the pressure receiving member 41 to the left and right
side frame segments 40b.
[0101] The claws 41c and 41d each are substantially L-shaped,
viewed from the right or left. That is, the claws 41c and 41d each
extend backward from the rear of the main body part 41a, bend, and
extend downward.
[0102] The pressure receiving member 41 includes a main body part
(pressure receiving part) 41a and a pair of the right and left
extending parts (supporting parts) 41b. The main body part 41a is a
plate-like member and extends vertically and horizontally. The left
extending part 41b extends leftward from the upper left side of the
main body part 41a. The right extending part 41b extends rightward
from the upper right side of main body part 41a. More specifically,
the extending parts 41b extend from the main body part 41a at the
breast height of the occupant diagonally forward to the outside in
the horizontal direction. The extending parts 41b curve forward
from the right and left sides of the main body part 41a. In top
view, the extending parts 41b and the main body part 41a, as a
whole, are curved into a cylindrical shape. The cylindrical shape
is concave viewing from the front and convex viewing from the rear.
The extending parts 41b and the main body part 41a are formed
integrally. The extending parts 41b are resiliently deformable.
[0103] FIG. 6 is a front view of the backrest 4. FIG. 7 is a
transverse sectional view, viewed from above, taken along line
VII-VII in FIG. 6. As shown in FIG. 7, a bead 41e is formed on the
front and rear surfaces of the right and left parts of the main
body part 41a. Each bead 41e is concave viewed from the front of
the main body part 41a and convex viewed from the rear of the main
body part 41a. The beads 41e extend vertically. Each extending part
41b extends from a lateral edge 41e1 of the bead 41e diagonally
forward to the lateral side.
[0104] In response to a backward load applied to the pressure
receiving member 41, the upper wire rod 43 and the lower wire rod
44 in FIGS. 2 to 4 are pulled backward by the pressure receiving
member 41. This causes elastic deformation of the upper wire rod 43
and the lower wire rod 44. This, in turn, causes the pressure
receiving member 41 to retreat backward. In response to a high
backward load, such as an impulsive force, the swing members 45a
are pulled by the lower wire rod 44 and moved backward against the
tensile force of the tension springs 45d. The pressure receiving
member 41 further retreats backward. The ends of the upper wire rod
43, which supports the upper portion of the pressure receiving
member 41, are fixed to the side frame segments 40b. The ends of
the lower wire rod 44, which supports the lower portion of the
pressure receiving member 41, are coupled to the side frame
segments 40b such that the ends of the lower wire rod 44 are
movable in the front-back direction by the swing members 45a. Thus,
the pressure receiving member 41 has a smaller backward
displacement in the upper direction and a larger backward
displacement in the lower direction.
[0105] While no backward load is applied to the pressure receiving
member 41 (hereinafter referred to as "natural state"), the
pressure receiving member 41 does not retreat. In such a natural
state, the pressure receiving member 41, the main body part 41a of
the pressure receiving member 41 and extending parts 41b are
inclined upward toward the rear.
[0106] With reference to FIG. 2 and FIGS. 5 to 8, a cushion pad 48
will now be described. FIG. 5 is a front view of a cushion pad 48.
FIG. 8 is a partial cross-sectional back view of the backrest 4 and
a partial longitudinal section of a cushion pad 48.
[0107] The cushion pad 48 is made of a cushion material, such as
urethane foam. The cushion pad 48 at least covers the front, left,
right and upper surfaces of the backrest frame 40 and the pressure
receiving member 41. The cushion pad 48 may further cover the rear
surface of the backrest frame 40 and the pressure receiving member
41.
[0108] As shown in FIG. 5, the cushion pad 48 has a back receiving
part (central part) 48a and right and left bank parts (side parts)
48b. The back receiving part 48a is the central portion of the
cushion pad 48. The left bank part 48b is the left part of the
cushion pad 48. The right bank part 48b is the right part of the
cushion pad 48. The back receiving part 48a and the bank parts 48b
are integrated such that the right bank part 48b is provided on the
right side of the back receiving part 48a and the left bank part
48b is provided on the left side of the back receiving part 48a. As
shown in FIG. 7, the bank parts 48b are provided such that they
protrudes forward from the right and left sides of the back
receiving part 48a. A valley is formed along the boundary between
the front surface of each bank part 48b and the front surface of
the back receiving part 48a.
[0109] Grooves 48c, 48c and 48d are formed on the front surface of
the cushion pad 48. The grooves 48c each extend vertically along
the boundary between each bank part 48b and the back receiving part
48a. The groove 48d is formed slightly above the central portion of
the front surface of the back receiving part 48a and extends in the
right-left direction. The left end of the groove 48d is in
communication with the left groove 48c. The right end of the groove
48d is in communication with the right groove 48c.
[0110] Slits 48e and 48f are formed in the bottom of the right
groove 48c. The holes in the slits 48e and 48f in the bottom of the
groove 48c extend through the back receiving part 48a and the bank
part 48b to the rear surfaces thereof. The slits 48e and 48f have
an elongated shape and extend vertically along each groove 48c. The
slit 48e is located above the slit 48f and slightly above the
central portion of the back receiving part 48a. The slit 48f is
located below the central portion of back receiving part 48a. Slits
48e and 48f are also formed in the bottom of the left groove 48c.
The slits 48e and the grooves 48c are each formed at the boundary
between the back receiving part 48a and each bank part 48b. Thus,
the back receiving part 48a readily retreats when pressed
backward.
[0111] As shown in FIG. 6, the back receiving part 48a covers the
front surfaces of the lower frame segment 40c, the main body part
41a of the pressure receiving member 41, the cross member 42, and
the upper frame segment 40a, as well as the upper surface of the
upper frame segment 40a. The left bank part 48b covers the front
surface of the left extending part 41b, as well as the front, left,
and rear surfaces of the left side frame segment 40b. The left bank
part 48b further covers the upper surface of the left end of the
upper frame segment 40a and the upper surface of the left side
frame segment 40b. The right bank part 48b covers the front surface
of the right extending part 41b, as well as the front, right, and
rear surfaces of the right side frame segment 40b. The right bank
part 48b further covers the upper surface of the right end of the
upper frame segment 40a and the upper surface of the right side
frame segment 40b.
[0112] The lateral width of the back receiving part 48a is shorter
than the lateral interval between the side frame segments 40b. The
back receiving part 48a is disposed between the side frame segments
40b when viewed from the front of the backrest 4. The grooves 48c
are located between the side frame segments 40b when viewed from
the front of the backrest 4.
[0113] The lateral width of the main body part 41a of the pressure
receiving member 41 is shorter than the lateral interval of the
grooves 48c, the lateral interval of the slits 48e, and the lateral
interval of the slits 48f. Thus, the main body part 41a of the
pressure receiving member 41 is located between the grooves 48c,
between the slits 48e, and between the slits 48f when viewed from
the front of the backrest 4.
[0114] The right extending part 41b of the pressure receiving
member 41 extends rightward from the right side of the main body
part 41a. The right extending part 41b extends across the right
slit 48e on the rear of the back receiving part 48a and the bank
part 48b. Similarly, the left extending part 41b extends across the
left slit 48e.
[0115] As shown in FIG. 7, the front surface of the main body part
41a of the pressure receiving member 41 is in contact with the rear
surface of the back receiving part 48a. The right extending part
41b is in contact with the right portion of the rear surface of the
back receiving part 48a and the left portion of the rear surface
(inside) of the right bank part 48b.
[0116] As shown in FIGS. 7 and 8, a recess 48g is formed at an
area, facing the right extending part 41b, of the rear (inner)
surface of the right extending part 41b. A step 48h is provided at
the right end (lateral side) of the recess 48g and protrudes from
the bottom of the recess 48g diagonally backward to the right
(lateral side). Thus, the right extending part 41b is in contact
with the left portion of the rear surface (inside) of the right
bank part 48b in the right recess 48g. In particular, a front edge
(front end or end of the extending part) 41b1 (See FIG. 7) of the
right extending part 41b is in contact with the rear surface
(inside) of the right bank part 48b in the right recess 48g.
[0117] Similarly, the left extending part 41b is also in contact
with the left portion of the rear surface of the back receiving
part 48a and the right portion of the rear surface (inside) of the
left bank part 48b. A recess 48g is formed at an area, facing the
left extending part 41b, of the rear (inner) surface of the left
extending part 41b. A step 48h is provided at the left end (lateral
side) of the recess 48g and protrudes from the bottom of the recess
48g diagonally backward to the left (lateral side). Thus, the left
extending part 41b is in contact with the left portion of the rear
surface (inside) of the left bank part 48b in the left recess 48g.
A front edge 41b1 of the left extending part 41b is also in contact
with the rear surface (inside) of the left bank part 48b in the
left recess 48g.
[0118] Each recess 48g is continuous with the slit 48e, extends
along the edge, adjacent to the bank part 48b, of the slit 48e, and
further extends toward the lateral side. Each recess 48g extends
from front of the main body part 40b2 of the side frame segment to
the slit 48e. The extending part 41b is located within the recess
48g. The contact portion between the extending part 41b and the
rear surface of the bank part 48b corresponds to the bottom of the
recess 48g. Each step 48h extends backward from the extending part
41b, with the rear summit of the step 48h positioned posterior to
the lateral end of the extending part 41b. Since the steps 48h
protrude diagonally backward to the lateral sides, the steps 48h
deviate from the trajectories of the extending parts 41b drawn at
backward retreat of the pressure receiving member 41.
[0119] The vertical length of each recess 48g is longer than that
of the corresponding extending part 41b. A gap 48i is provided
between the upper edge of the extending part 41b and the upper
inner circumferential wall of the recess 48g. A gap 48j is provided
between the lower edge of the extending part 41b and the lower
inner circumferential wall of the recess 48g. The lower gap 48j is
larger than the upper gap 48i.
[0120] The vertical length of each slit 48e is longer than that of
the corresponding extending part 41b and that of the corresponding
recess 48g. The upper portion of each slit 48e extends upward from
the upper inner circumferential wall of the recess 48g, and the top
end of the slit 48e is located above the upper inner
circumferential wall of the recess 48g. The lower portion of the
slit 48e extends downward from the lower inner circumferential wall
of the recess 48g. The bottom end of the slit 48e is located above
the lower inner circumferential wall of the recess 48g.
[0121] Since each recess 48g is formed on the rear surface of the
bank part 48b, the bank part 48b is thin in the recess area where
the recess 48g is formed. The thinned portion of the bank part is
referred to as a thin wall 48k. A gap between the thin wall 48k and
the main body part 40b2 of the side frame segment corresponds to
the recess 48g. The thin wall 48k is harder than the other portion
of the bank part 48b because voids are not formed in the thin wall
48k at the formation of foams in the cushion pad 48. Thus, the thin
wall 48k has a lower porosity than other portion.
[0122] As shown in FIG. 7, one end 48k1 of the thin wall 48k is in
contact with the extending part 41b. A lateral edge 41e1 of the
bead 41e is in contact with the lateral edge, adjacent to the slit
48e, of the rear surface of the back receiving part 48a. The
contact portion between the end 48k1 of the thin wall 48k and the
extending part 41b lies anterior to the contact portion between the
lateral edge 41e1 of the bead 41e and the lateral edge of the rear
surface of the back receiving part 48a.
[0123] The skin 49 is stretched over the surface of the cushion pad
48. This indicates that the skin 49, which covers the front surface
of the cushion pad 48, extends along the cushion pad 48 while the
skin 49 is tensioned. Multiple first engaging members are provided
on the rear surface of the skin 49. The first engaging members are
disposed along the grooves 48c and 48d while avoiding the slits
48e. Multiple second engaging members are also disposed on the
bottoms of the grooves 48c and 48d. The second engaging members are
disposed along the grooves 48c and 48d avoiding the slits 48e. The
first engaging members are inserted into the grooves 48c and 48d,
while the skin 49 is tensioned and then engaged with the second
engaging members, thus maintaining the tension of the skin 49. The
skin 49 is stretched over the surface of the cushion pad 48 in such
a manner.
[0124] The skin 49 is composed of several parts. These parts are
sewn together to form the skin 49 into a bag. More specifically,
the skin 49 includes front skin part 49a, a pair of right and left
bank skin parts 49b, a pair of right and left side skin parts 49c
and a back skin part. The bank skin parts 49b are sewn to the right
and left sides of the front skin part 49a. The left side skin part
49c is sewn to the left side of the left bank skin part 49b. The
right side skin part 49c is sewn to the right side of the right
bank skin part 49b. The back skin part is sewn to the upper side of
the front skin part 49a. The back skin part is folded back such
that it comes into contact with the rear surface of the front skin
part 49a. The side skin parts 49c are connected to right and left
sides of the back skin part with a fastener such that the skin 49
can be opened and closed freely.
[0125] The cushion pad 48 and the backrest frame 40 are placed in
the skin 49. The cushion pad 48 is covered with the skin 49. The
front skin part 49a covers the front surface of the back receiving
part 48a. The bank skin parts 49b cover the front surfaces of the
bank parts 48b. The side skin parts 49c cover the side and rear
surfaces of the bank parts 48b. The back skin part covers the rear
surface of the backrest frame 40.
[0126] As shown in FIG. 8, a pair of right and left pull strips
(pull members) 49e are coupled to the rear surface of the skin 49
by sewing, bonding or adhesion. More specifically, the pair of
right and left pull strips (pull members) 49e are coupled to the
seams between the front skin part 49a and the bank skin parts 49b
inside the skin 49 by sewing, bonding or adhesion. More
specifically, each of pull strip 49e is sewn to the front skin part
49a and the bank skin part 49b, while the pull strip 49e is
sandwiched between the end of the front skin part 49a and the end
of the bank skin part 49b. Each connection portion between the pull
strip 49e and the skin 49 overlaps with the position of the slit
48e.
[0127] Each pull strip 49e extends through the slit 48e and is
routed from the front surface of the back receiving part 48a and
the bank part 48b to the rear surface thereof. The pull strips 49e
are bonded together by a hook and loop fastener 49g on the rear
surface of the back receiving part 48a, while the skin 49 is pulled
backward by the pull strips 49e. The pull strips 49e are tensioned.
The back receiving part 48a is tightened and compressed by the pull
strips 49e. The width of each slit 48e is expanded by the pull
strip 49e. This is how the skin 49 is stretched over the surface of
the cushion pad 48, thereby maintaining the tension of the skin
49.
[0128] To prevent the hook and loop fastener 49g from being caught
between the back receiving part 48a and the pressure receiving
member 41, a dent 48m is formed on the portion of the rear surface
of the back receiving part 48a that overlaps with the hook and loop
fastener 49g. This can prevent an abnormal noise that would be
generated when the hook and loop fastener 49g comes into contact
with the back receiving part 48a, the pressure receiving member 41
or both.
[0129] The operation and use of the seat 1 with such a
configuration will now be described.
[0130] An occupant is seated on the bottom seat 3 and leans the
upper body 99a against the backrest 4 as shown in FIG. 9A. The
occupant is often seated with the head slightly spaced apart from
the headrest toward the front.
[0131] The back of the occupant is received by the front surface of
the back receiving part 48a. The back receiving part 48a is
resiliently compressed. The bank parts 48b receive the right and
left sides of the upper body 99a of the occupant (mainly shoulders,
shoulder blades, franks, upper arms, etc.) and are slightly
compressed. The extending parts 41b mainly support the rear-half of
the sides of the breast-height part of the occupant's upper body
via bank parts 48b. Since the bank parts 48b (thin walls 48k) are
supported from the rear by the extending parts 41b, the thin walls
48k are not significantly bent backward even if the thin walls 48k
are pressed backward by the upper body 99a of the occupant. The
extending parts 41b of the pressure receiving member 41 can achieve
enough ability to laterally hold the upper body 99a of the occupant
in spite of the recesses 48g. Although the thin walls 48k are
harder than other portion and have reduced cushioning performance,
the extending parts 41b can compensate for the reduced cushioning
performance.
[0132] The slits 48e help backward deformation of the thin walls
48k. The thin walls 48k, however, are not significantly bent
backward even if the upper body 99a of the occupant leaning against
the backrest 4 presses the thin walls 48k backward since the
extending parts 41b, which extend across the slits 48e, receive the
thin walls 48k from the rear. Thus, the upper body 99a of the
occupant can be laterally held.
[0133] In addition, the support of the back of the occupant by the
surface of the pressure receiving member 41 stabilizes the sitting
posture of the occupant.
[0134] Each extending part 41b is in contact with the rear surface
of the bank part 48b (thin wall 48k) even if the occupant does not
lean against the backrest 4. When the occupant leans against the
backrest 4, the upper body 99a of the occupant is laterally held by
the bank parts 48b. The ability to laterally hold the upper body
99a of the occupant can be maintained regardless of the weight of
the occupant.
[0135] At a rear-end collision by a vehicle running back (with the
seat 1 mounted) against another vehicle or an obstacle or at a
rear-end collision by another vehicle, a backward inertial force is
applied to the occupant and the seat 1. In such a case, the back
receiving part 48a and the pressure receiving member 41 retreat
(refer to FIG. 9B). The upper body 99a sinks backward while the
occupant leaning against the backrest 4 is hunched over. Almost at
the same time, the back of occupant's head hits the headrest 6.
This indicates that the back of occupant's head is received by the
headrest 6 while the upper body 99a of the occupant is hunched
over. This can prevent the backward tilting of the neck region of
the occupant, thus reducing load applied to the neck region.
[0136] The rear surface of the upper portion of the back receiving
part 48a is supported by the cross member 42. The central and lower
portions of the back receiving part 48a retreat along with the
pressure receiving member 41. This is likely to cause the upper
body 99a of the occupant to be hunched over. The back of occupant's
head is received by the headrest 6 in concurrence with the retreat
of the upper body 99a of the occupant in a hunched posture. This
can prevent the backward tilting of the neck region of the
occupant, thus reducing load applied to the neck region.
[0137] The slits 48e and 48f, which are formed between the back
receiving part 48a and each bank part 48b, cause the back receiving
part 48a and the pressure receiving member 41 to retreat
significantly. At the time of retreat, the thin walls 48k of the
bank parts 48b are pressed backward by the right and left sides of
the upper body 99a of the occupant (mainly shoulders, shoulder
blades, franks, upper arms, etc.) and the thin walls 48k of the
bank parts 48b are bent backward. The extending parts 41b of the
pressure receiving member 41 are also pressed backward by the thin
walls 48k and the extending parts 41b are bent backward
resiliently. Since the front edge 41b1 of each extending part 41b
(see FIG. 7) is in contact with the rear surface of the thin wall
48k, the extending parts 41b are likely to bend backward. The
recesses 48g are formed on the rear surfaces of the bank parts 48b.
This indicates that a space for retreating the thin walls 48k and
the extending parts 41b of the pressure receiving member 41 is
disposed on the rear of the bank parts 48b. This configuration can
prevent the bank parts 48b from reducing the backward sinking of
the upper body 99a of the occupant.
[0138] Since the contact portion between the end 48k1 of each thin
wall 48k and the extending part 41b lies anterior to the contact
portion between the lateral edge 41e1 of the bead 41e and the
lateral edge of the rear surface of the back receiving part 48a
(See FIG. 7), the extending part 41b is more likely to bend
backward. Since each extending part 41b extends from the lateral
edge 41e1 of the bead 41e diagonally forward to the lateral side
(See FIG. 7), the extending part 41b is more likely to bend
backward at an opposite lateral edge 41e2 of the bead 41e.
[0139] Since the vertical length of each slit 48e is greater than
that of the extending part 41b, the back receiving part 48a and the
main body part 41a of the pressure receiving member 41 are likely
to retreat, the thin walls 48k of the bank parts 48b are likely to
bend backward, and the extending parts 41b of the pressure
receiving member 41 are likely to retreat. All of this can prevent
the cushion pad 48 from reducing the backward sinking of the upper
body 99a of the occupant.
[0140] Since the widths of the slits 48e are expanded by the pull
strips 49e, the back receiving part 48a is likely to retreat and
the thin walls 48k of the bank parts 48b are likely to bend
backward. This can prevent the cushion pad 48 from reducing the
backward sinking of the upper body 99a of the occupant.
[0141] The gaps 48i and 48j are provided at the upper and lower
edges of the extending part 41b. This prevents the bank parts 48b
from reducing the retreat of extending parts 41b and the backward
deformation of the extending parts 41b. This can prevent the
extending parts 41b from reducing the backward sinking of the upper
body 99a of the occupant.
[0142] A larger impulsive force moves the swing members 45a
backward against the tensile load of the tension springs 45d and
causes the pressure receiving member 41 to further retreat. With
the backward movement of the swing members 45a, the backward
displacement of the pressure receiving member 41 decreases toward
the upper portion and increases toward the lower portion. The lower
gaps 48j, which are larger than the upper gaps 48i, can prevent the
bank parts 48b from reducing the retreat of the extending parts 41b
when the pressure receiving member 41 moves backward in such a way
as mentioned above. This can prevent the extending parts 41b from
reducing the backward sinking of the upper body 99a of the
occupant.
[0143] Since the lower portion of each slit 48e extends downward
from the lower inner circumferential wall of the recess 48g, the
lower portion of back receiving part 48a is likely to retreat. This
causes the back receiving part 48a to retreat along with the
pressure receiving member 41 even if the pressure receiving member
41 has an increasing backward displacement toward its bottom
end.
[0144] Since the steps 48h protrude diagonally backward to the
lateral sides, the steps 48h bend toward the lateral sides such
that the recesses 48g open at the time of the backward deformation
of the thin walls 48k of the bank parts 48b. This prevents the
steps 48h from reducing the backward deformation of the extending
parts 41b. This can prevent the extending parts 41b from reducing
the backward sinking of the upper body 99a of the occupant.
[0145] Each step 48h protrudes diagonally backward to the lateral
side such that the step 48h deviates from the trajectory of the
front edge 41b1 of the extending part 41b (See FIG. 7) drawn when
the extending part 41b is pressed and bent backward by the thin
wall 48k. This prevents the steps 48h from reducing the backward
deformation of the extending parts 41b.
[0146] Since the mounts 43a are attached to the vertical pipe
segments 40b1 not at the front ends thereof, the front edges 41b1
of the extending parts 41b do not come into contact with the mounts
43a when the extending parts 41b are pressed and bent backward by
the thin walls 48k. This prevents the mounts 43a from reducing the
backward deformation of the extending parts 41b.
[0147] The thin walls 48k, which are harder than other portion,
prevent the distribution of the inertial force applied when the
upper body 99a of the occupant sinks backward over the bank parts
48b, thus making the thin walls 48k of the bank parts 48b more
likely to bend backward. This can prevent the bank parts 48b from
reducing the backward sinking of the upper body 99a of the
occupant.
[0148] The scope of the present invention should not be limited to
the above embodiment and various changes and modifications can be
made without departing from the spirit and scope of the present
invention.
[0149] In the above description, the seat 1 is a vehicle seat used
in an automobile, but may be used for other means of
transportation, such as railway, vessels and airplanes.
Additional Statement on First Embodiment
[0150] As is evident from the above description, the description of
the first embodiment includes various disclosures on technical
ideas in addition to the aspect of the invention described in the
following notes.
Note 1.
[0151] A seat backrest, including:
[0152] right and left side frame segments disposed in parallel in a
right-left direction;
[0153] a pressure receiving member disposed between the side frame
segments, the pressure receiving member being movable in a
front-back direction; and
[0154] a cushion pad covering front surfaces of the side frame
segments and a front surface of the pressure receiving member,
[0155] wherein the pressure receiving member includes: [0156] a
main body part; and [0157] right and left extending parts extending
rightward and leftward from right and left sides of the main body
part,
[0158] wherein the cushion pad includes: [0159] a back receiving
part covering a front surface of the main body part, and [0160]
bank parts disposed on right and left sides of the back receiving
part, protruding forward from right and left sides of a front
surface of the back receiving part, and covering front surfaces of
the extending parts and the front surfaces of the side frame
segments, and
[0161] wherein a recess is formed at an area of a rear surface of
each bank part, the area facing a corresponding extending part of
the extending parts.
Note 2.
[0162] The seat backrest according to Note 1, wherein each
extending part is in contact with the rear surface of the bank part
in the recess.
Note 3.
[0163] The seat backrest according to Note 1 or 2, wherein
[0164] each extending part fits in the recess and
[0165] each extending part is away from an inner circumferential
wall of the recess.
Note 4.
[0166] The seat backrest according to Note 3, wherein a gap between
a lower inner circumferential wall of the recess and the extending
part is larger than a gap between an upper inner circumferential
wall of the recess and the extending part.
Note 5.
[0167] The seat backrest according to one of Notes 1 to 4, wherein
the area of the recess of each bank part is harder than other area
of the bank part.
Note 6.
[0168] The seat backrest according to one of Notes 1 to 5, wherein
a step protrudes from a bottom of each recess diagonally backward
to a lateral side, the step being a lateral edge of the recess.
Note 7.
[0169] The seat backrest according to Note 6, wherein each step
protrudes diagonally backward to the lateral side such that the
step deviates from a trajectory of a front edge of the extending
part, the trajectory being drawn when the extending part is pressed
and bent backward by the area of the recess of the bank part.
Note 8.
[0170] The seat backrest according to one of Notes 1 to 7, wherein
the cushion pad has right and left slits, each slit being formed at
a boundary between the back receiving part and the corresponding
bank part and penetrating from a front surface to a rear surface of
the cushion pad, and
[0171] wherein each extending part extends across the corresponding
slit on a rear of the back receiving part and the bank part.
Note 9.
[0172] The seat backrest according Note 8, wherein a vertical
length of the slit is greater than a vertical length of the
extending part.
Note 10.
[0173] The seat backrest according to Note 8 or 9, wherein each
recess is disposed along an edge, adjacent to the bank part, of the
slit and extends from the edge, adjacent to the bank part, of the
slit toward a lateral side, and
[0174] wherein each slit extends downward from a lower inner
circumferential wall of the recess.
Note 11.
[0175] The seat backrest according to one of Notes 8 to 10, further
including:
[0176] a skin covering the cushion pad;
[0177] right and left pulling members disposed on a rear surface of
the skin; and
[0178] a hook and loop fastener disposed on the pulling
members,
[0179] wherein the pulling members extend through the slits and are
routed to a rear surface of the back receiving part, the back
receiving part is tightened with the pulling members, the pulling
members are bonded with the hook and loop fastener, and a dent is
formed at an area on the rear surface of the back receiving part,
the area overlapping with the hook and loop fastener.
(a) Advantageous Effects of Present Invention Described in Note
1
[0180] Recesses are formed on the rear surfaces of the bank parts
to provide a space into which the recess areas of the bank parts
retreat and bend. Upon a rear-end collision by another vehicle, the
bank parts receive the sides of the upper body of an occupant,
while the recess areas of the bank parts retreat and bend. This can
prevent the bank parts from reducing the backward sinking of the
upper body of the occupant.
[0181] When an occupant leans against the backrest, the recess
areas of the bank parts are received by the extending parts of the
pressure receiving member. Although the recesses on the rear
surfaces of the bank parts reduce the holding ability of the bank
parts themselves, the extending parts can compensate for the
reduced holding ability.
(b) Advantageous Effects of Present Invention Described in Note
2
[0182] The extending parts are in contact with the rear surfaces of
the bank parts in the recesses. When an occupant leans against the
backrest, the recess areas of the bank parts are readily received
by the extending parts of the pressure receiving member. Thus, the
extending parts enhance the advantageous effects of the
supplemental holding ability.
(c) Advantageous Effects of Present Invention Described in Note
3
[0183] Since each extending part is apart from the inner
circumferential wall of the recess, the extending parts do not come
into contact with the inner circumferential walls of the recesses
at the time of retreat of the extending parts along with the recess
areas of the bank parts. This can prevent the extending parts from
reducing the backward sinking of the upper body of the
occupant.
(d) Advantageous Effects of Present Invention Described in Note
4
[0184] If the pressure receiving member has an increasing backward
displacement toward its bottom end at a rear-end collision by
another vehicle, contact between each extending part and the inner
circumferential wall of the recess can be avoided since the gap
between the lower inner circumferential wall of each recess and the
extending part is larger than the gap between the upper inner
circumferential wall of the recess and the extending part. This can
prevent the extending parts from reducing the backward sinking of
the upper body of the occupant.
(e) Advantageous Effects of Present Invention Described in Note
5
[0185] The recess areas, which are harder than other portions,
prevent the distribution of the inertial force applied at the time
of backward pressing of the recess areas by the upper body of an
occupant over the bank parts. This action facilitates backward
deformation of the recess areas. This can prevent the bank parts
from reducing the backward sinking of the upper body of the
occupant.
(f) Advantageous Effects of Present Invention Described in Note
6
[0186] Since the steps protrude diagonally backward to the lateral
sides, the steps bend toward the lateral sides such that the
recesses open at the time of the backward deformation of the recess
areas. This prevents the steps from reducing the retreat and
backward deformation of the extending parts. This can prevent the
extending parts from reducing the backward sinking of the upper
body of the occupant.
(g) Advantageous Effects of Present Invention Described in Note
7
[0187] The steps can maintain proper retreat and backward
deformation of the extending parts. This prevents the extending
parts from reducing the backward sinking of the upper body of the
occupant.
(h) Advantageous Effects of Present Invention Described in Note
8
[0188] The slit formed in the boundary between the back receiving
part and each bank part can cause the back receiving part and the
pressure receiving member to retreat significantly. This enables
the upper body of the occupant to more readily sink backward at a
rear-end collision by another vehicle.
[0189] The formed slits enable the recess areas to readily bend
backward. Since each extending part extends across the slit and
faces the recess area, the recess areas do not significantly bend
backward at the time of backward pressing of the recess areas by
the upper body of the occupant leaning against the backrest. Thus,
the upper body of the occupant can be laterally held.
(i) Advantageous Effects of Present Invention Described in Note
9
[0190] The vertical length of each slit, which is greater than that
of the extending part, enables the back receiving part and the main
body part of the pressure receiving member to readily retreat, the
recess areas to readily bend backward, and the extending parts of
the pressure receiving members to readily retreat. This can prevent
the cushion pad from reducing the backward sinking of the upper
body of an occupant.
(j) Advantageous Effects of Present Invention Described in Note
10
[0191] The lower portion of each slit, which extends downward from
the lower inner circumferential wall of the recess, enables the
lower portion of the back receiving part to readily retreat. This
structure facilitates backward sinking of the upper body of the
occupant at a rear-end collision by another vehicle.
(k) Advantageous Effects of Present Invention Described in Note
11
[0192] The pulling members passing through the slits tighten the
back receiving part and thus expand the width of each slit. This
structure facilitates backward sinking of the upper body of the
occupant at a rear-end collision by another vehicle.
[0193] A dent is formed on the portion that overlaps with the hook
and loop fastener on the rear surface of the back receiving part to
prevent the hook and loop fastener from being caught between the
back receiving part and the pressure receiving member. This
structure can prevent an abnormal noise that would be generated by
the contact between the hook and loop fastener and the back
receiving part, the pressure receiving member or both.
Second Embodiment
[0194] FIG. 10 is a perspective view of a seat 1A according to a
second embodiment of the present invention. The same parts between
the seat 1A according to the second embodiment and the seat 1
according to the first embodiment are given the same reference
numerals. If the same parts are provided in the same manner, the
explanation thereof will be omitted if possible. The following
description focuses on differences between the seat 1A according to
the second embodiment and the seat 1 according to the first
embodiment.
[0195] The seat 1A is a vehicle seat, in particular an automotive
seat. The seat 1A includes slide rails 2, a bottom seat 3, a
recliner mechanism 5, and a headrest 6. These are provided in the
same way as the slide rails 2, the bottom seat 3, the recliner
mechanism 5, and the headrest 6 of the seat 1 according to the
first embodiment.
[0196] FIG. 11 is an exploded perspective view of the backrest 4.
FIG. 12 is a perspective view of a side frame segment 40b of the
backrest 4. FIG. 13 is a side view of the backrest 4. FIG. 14 is a
transverse sectional view of the left portion of the backrest 4 in
top view. FIG. 15 is a longitudinal sectional view of the cushion
pad 48 and a partial cross-sectional back view of the backrest
4.
[0197] As shown in FIGS. 11 to 15, the backrest 4 includes a
backrest frame 40, a pressure receiving member 41, a cross member
42, an upper wire rod 43, a lower wire rod 44, a cushion pad 48 and
a skin 49, similarly to the first embodiment. The backrest 4
further includes an airbag module 50, a reinforcing cloth (guide
cloth) 51, upper and lower reinforcing cloth attaching members 52
and a side support member 40d.
[0198] The backrest frame 40 in the second embodiment is provided
in the same manner as that in the first embodiment.
[0199] The pressure receiving member 41 in the second embodiment is
provided in the same manner as that in the first embodiment, except
for beads 41b4. As shown in FIG. 12, the beads 41b4 are formed in
the extending parts 41b and extend in the right-left direction. The
beads 41b4 each have a concave shape on the front surfaces of the
extending parts 41b and a convex shape on the rear surfaces of the
extending parts 41b. The beads 41b4 enhance the rigidity of the
extending parts 41b.
[0200] The beads 41b4 may each have a convex shape on the front
surfaces of the extending parts 41b and a concave shape on the rear
surfaces of the extending parts 41b. The beads 41b4 may be formed
on the extending parts 41b also in the first embodiment.
[0201] The cushion pad 48 in the second embodiment is also provided
in the same manner as that in the first embodiment, except for a
storage space 48s. The storage space 48s is formed on the left of
the cushion pad 48 in the second embodiment to store an airbag
module 50. More specifically, the storage space 48s is formed on
the left side of the left bank part 48b and extends from the left
side to the inside of the left bank part 48b. An airbag module 50
is stored in the storage space 48s. The airbag module 50 is
embedded in the left portion of the cushion pad 48 and the skin 49
covers the cushion pad 48 and the airbag module 50 such that the
airbag module 50 is exposable from the left side of the cushion pad
48. More specifically, a left bank skin part 49b covers the airbag
module 50 and blocks the storage space 48s.
[0202] The airbag module 50 will now be described.
[0203] As shown in FIGS. 10 to 15, the airbag module 50 is in
contact with the outside (left) of a left side frame segment 40b.
The airbag module 50 includes at least an inflator and an airbag,
and if necessary, a retainer, a lid, an impact sensor, and a
control circuit. Upon detection of a vehicle impact by the impact
sensor, a signal from the impact sensor is input to the inflator
via the control circuit. In response to the signal, the inflator is
ignited. The gas generated in the inflator inflates the airbag
instantly.
[0204] As shown in FIGS. 11 and 13, a side support member 40d is
attached to the front end of the right side frame 40b by welding.
The side support member 40d is composed of a rod member bent in a
hook shape. The side support member 40d includes a vertical section
40d1 and a bent section 40d2. The vertical section 40d1 is apart
from the front surface of the side frame segment 40b and extends
vertically. The bent section 40d2 is bent backward at the top end
of the vertical section 40d1 and then further bent downward. The
rear end of the bent section 40d2 is fixed to the upper front end
of the main body part 40b2 of the side frame segment by welding.
The bottom end of the vertical section 40d1 is fixed to a portion
above the front end of a protrusion 40b3 by welding. In lateral
view, an area 40d3 surrounded by the front surface of the side
frame segment 40b and the side support member 40d is formed between
the vertical section 40d1 and the front surface of the side support
member 40d.
[0205] In lateral view (see FIG. 13), the front edges (front ends
or ends of the extending parts) 41b1 of the right and left
extending parts 41b are each disposed within the area 40d3
surrounded by the front end of the side frame segment 40b and the
side support member 40d. The front surface of the side support
member 40d is covered with a right bank part 48b of the cushion pad
48. The side support member 40d supports the right bank part 48b
from the back and causes the bank part 48b to protrude forward. The
side support member 40d may be provided in the first
embodiment.
[0206] The skin 49 and its stretching will now be described. In the
portion of grooves 48c and 48d without slits 48e and 48f, the inner
surface of the skin 49 is fixed to the cushion pad 48 by an
engaging member, such as a C ring. A hook 49f is provided at the
end of each side skin part 49c. The hook 49f is hooked to the side
frame segment 40b. The skin 49 is stretched over the surface of the
cushion pad 48 in such a manner as to maintain the tension of the
skin 49.
[0207] As shown in FIGS. 14 and 15, a pair of right and left pull
strips (pulling members) 49e are coupled to a seam between a front
skin part 49a and the bank skin parts 49b by sewing, bonding or
adhesion inside the skin 49. More specifically, each pull strip 49e
is sewn to the front skin part 49a and the bank skin part 49b,
while it is sandwiched between the end of the front skin part 49a
and the end of the bank skin part 49b. The connection portions
between the skin 49 and the pull strips 49e overlap with the
positions of the slits 48e. Each pull strip 49e extends through the
slit 48e and is routed from the front surface of the back receiving
part 48a and the bank part 48b to the rear surface thereof. The
pull strips 49e are bonded together by a hook and loop fastener 49g
on the rear surface of the back receiving part 48a, while the skin
49 is pulled backward by the pull strips 49e. The pull strips 49e
are tensioned. The back receiving part 48a is tightened by the pull
strips 49e. The skin 49 is stretched over the surface of the
cushion pad 48 in such a manner, thereby maintaining the tension of
the skin 49.
[0208] A dent 48m is formed on the portion of the rear surface of
the back receiving part 48a that overlaps with the hook and loop
fastener 49g to prevent the hook and loop fastener 49g from being
caught between the back receiving part 48a and the pressure
receiving member 41. This can prevent an abnormal noise that would
be generated by the contact between the hook and loop fastener 49g
and the back receiving part 48a, the pressure receiving member 41
or both.
[0209] As shown in FIG. 16, a first engaging member 49d and a
second engaging member 48u, instead of the pull strips 49e, may be
used to stretch the skin 49 over the surface of the cushion pad 48.
Multiple first engaging members 49d are provided inside the skin 49
at the seam between the front skin part 49a and each bank skin part
49b. The first engaging members 49d are disposed along the grooves
48c. The second engaging member 48u is also provided in the portion
of each groove 48c that overlaps with the slit 48e. The first
engaging members 49d are inserted into the grooves 48c while the
skin 49 remains tensioned to engage the first engaging members 49d
with the second engaging members 48u.
[0210] As shown in FIG. 11, a planned rupture portion 49t is
provided on the skin 49. The planned rupture portion 49t is formed
at the front of the side portion of a left bank part 48b. The seam
between the left side skin part 49c and a left bank skin part 49b
is the planned rupture portion 49t. The planned rupture portion 49t
has lower strength than the other portion of the skin 49. The seam
of the planned rupture portion 49t has lower strength than that of
other seams on the skin 49. The seam of the planned rupture portion
49t has strength that can endure normal use but causes the seam to
rupture with a tensile force applied at the inflation of the airbag
in the airbag module 50.
[0211] A reinforcing cloth 51 and reinforcing cloth attaching
members 52 will now be described.
[0212] As shown in FIG. 14, the reinforcing cloth 51 has one end
51a coupled to the inside of the skin 49. More specifically, the
one end 51a of the reinforcing cloth 51 is sewn to the left bank
skin part 49b and the side skin part 49c at the planned rupture
portion 49t.
[0213] The reinforcing cloth 51 has other end 51b coupled to the
side frame segment 40b via the reinforcing cloth attaching member
52. FIG. 17 is a cross-sectional view showing how the reinforcing
cloth attaching member 52 is attached to the side frame segment
40b. As shown in FIG. 17, the reinforcing cloth attaching member 52
is a clip made of a resin material. The reinforcing cloth attaching
member 52 includes a spiral structure 52a, a spiral notch 52b, an
engaging portion 52c and an arc notch 52d. The spiral structure 52a
has arms wound with a gap formed between the arms. A gap created by
the arm of the spiral structure 52a is the spiral notch 52b. The
spiral notch 52b is opened at the outermost part of the spiral
structure 52a. The engaging portion 52c extends from a near-center
portion of the outermost periphery of the spiral structure 52a
along the outermost periphery of the spiral structure 52a. A gap is
formed between the engaging portion 52c and the spiral notch 52b.
The gap is the arc notch 52d. The arc notch 52d opens at the end of
the engaging portion 52c. The front end 40b5 of each side frame
segment 40b (the main body part 40b2 of each side frame segment) is
curved into a hook (the curved portion is hereinafter referred to
as "hook 40b5"). The end of the hook 40b5 is inserted into the arc
notch 52d. The spiral structure 52a is disposed inside the hook
40b5. The end of the hook 40b5 is held between the spiral structure
52a and the engaging portion 52c. The reinforcing cloth attaching
member 52 is thereby attached to the side frame segment 40b. One
end of the reinforcing cloth 51 is inserted into the spiral notch
52b, wound along the spiral notch 52b, and thus held by the spiral
structure 52a. The reinforcing cloth attaching member 52 is
attached to the end of the reinforcing cloth 51 in such a manner. A
plate-like or rod-like filling member may be inserted into the
spiral notch 52b so that the end of the reinforcing cloth 51 can be
securely held by the spiral structure 52a.
[0214] As shown in FIG. 14, the reinforcing cloth 51 is stretched
from the planned rupture portion 49t to each reinforcing cloth
attaching member 52 via the periphery of the airbag module 50,
while it is tensioned. More specifically, the reinforcing cloth 51
is stretched over the side of the bank part 48b from the front of
the side surface of the left bank part 48b to the edge of the
storage space 48s. The reinforcing cloth 51 further extends from
the edge of the storage space 48s to the side frame segment 40b
through the storage space 48s, while it is tensioned.
[0215] The reinforcing cloth 51 is composed of less stretching
cloth. The inflation of the airbag in the airbag module 50
increases the tension of the reinforcing cloth 51. The reinforcing
cloth 51 works to transmit the tension to the planned rupture
portion 49t. The reinforcing cloth 51 is a guide member that guides
the direction of deploying the airbag. The airbag is guided toward
the planned rupture portion 49t by reinforcing cloth 51 during the
inflation of the airbag in the airbag module 50. When the airbag
inflates, it protrudes forward through the planned rupture portion
49t.
[0216] The positions of the reinforcing cloth attaching members 52
will now be described.
[0217] The reinforcing cloth attaching members 52 are positioned so
as to deviate from the trajectory, drawn at a time of a front-back
movement of the pressure receiving member 41, of the left extending
part 41b (See FIGS. 11 to 14).
[0218] The lower reinforcing cloth attaching member 52 is attached
to the side frame segment 40b at a position anterior to a front
edge 41b1 of the left extending part 41b while the pressure
receiving member 41 is in the natural state (a backward load is not
applied to the pressure receiving member 41 and thus the pressure
receiving member 41 does not retreat) (See FIGS. 13 and 14).
[0219] The upper reinforcing cloth attaching member 52 is attached
to the side frame segment 40b above the lower edge 41b2 of the left
extending part 41b while the pressure receiving member 41 is in the
natural state (See FIGS. 11 to 13). The lower reinforcing cloth
attaching member 52 is attached to the side frame segment 40b below
the lower edge 41b2 of the left extending part 41b while the
pressure receiving member 41 is in the natural state (See FIGS. 11
to 13).
[0220] The upper reinforcing cloth attaching member 52 is attached
to the side frame segment 40b above an upper edge 41b3 of the left
extending part 41b while the pressure receiving member 41 is in the
natural state (See FIGS. 11 to 13). In other words, the reinforcing
cloth attaching members 52 are attached to the side frame segment
40b at a position above the left extending part 41b and below the
left extending part 41b while the pressure receiving member 41 is
in the natural state. Either the upper reinforcing cloth attaching
member 52 or the lower reinforcing cloth attaching member 52 may be
omitted, i.e., one reinforcing cloth attaching member 52 may be
attached to the side frame segment 40b above the left extending
part 41b or below the left extending part 41b while the pressure
receiving member 41 is in the natural state.
[0221] The reinforcing cloth attaching members 52 are each attached
to the side frame segment 40b above or below a most forward
protruding portion 40b4 of the protrusion 40b3 (See FIG. 13).
[0222] The reinforcing cloth attaching members 52 are each attached
to the side frame segment 40b above or below the beads 41b4 while
the pressure receiving member 41 is in the natural state (See FIG.
12).
[0223] The upper reinforcing cloth attaching member 52 is disposed
above the left extending part 41b. The lower reinforcing cloth
attaching member 52 is disposed below the left extending part 41b.
These reinforcing cloth attaching members 52 are vertically
separated from each other. This leads to a stable attachment of the
reinforcing cloth 51.
[0224] The operation and use of the seat 1A with such a
configuration will now be described.
[0225] An occupant is seated on the bottom seat 3 and leans the
upper body against the backrest 4. The occupant is often seated
with the head slightly spaced apart from the headrest toward the
front.
[0226] The back of the occupant is received by the front surface of
the back receiving part 48a. The back receiving part 48a is
resiliently compressed. The bank parts 48b receive the right and
left sides of the upper body 99a of the occupant (mainly shoulders,
shoulder blades, franks, upper arms, etc.) and are slightly
compressed. Since the bank parts 48b (thin walls 48k) are supported
from the rear by the extending parts 41b, the thin walls 48k are
not significantly bent backward even if the thin walls 48k are
pressed backward by the upper body of the occupant. Thus, the
extending parts 41b of the pressure receiving member 41 can prevent
the reduction in the ability to laterally hold the upper body of
the occupant due to recesses 48g.
[0227] The slits 48e, which are formed on the bottom of the grooves
48c, help backward deformation of the thin walls 48k. The thin
walls 48k, however, are not significantly bent backward even if the
upper body of the occupant leaning against the backrest 4 presses
the thin walls 48k backward since the extending parts 41b, which
extend across the slits 48e, receive the thin walls 48k from the
rear. Thus, the upper body of the occupant can be laterally
held.
[0228] Each extending part 41b is in contact with the rear surface
of the bank part 48b (thin wall 48k) even if the occupant does not
lean against the backrest 4. When the occupant leans against the
backrest 4, the upper body of the occupant is laterally held by the
bank parts 48b. The ability to laterally hold the upper body of the
occupant can be maintained regardless of the weight of the
occupant.
[0229] At a rear-end collision by a vehicle running back (with the
seat 1A mounted) against another vehicle or an obstacle or at a
rear-end collision by another vehicle, a backward inertial force is
applied on the occupant and the seat 1A. In such a case, the back
receiving part 48a and the pressure receiving member 41 retreat.
The upper body sinks backward while the occupant leaning against
the backrest 4 is hunched over. Almost at the same time, the back
of occupant's head hits the headrest 6. This indicates that the
back of occupant's head is received by the headrest 6 while the
upper body of the occupant is hunched over. This can prevent the
backward tilting of the neck region of the occupant, thus reducing
load applied to the neck region.
[0230] The slits 48e, which are formed between the back receiving
part 48a and the bank parts 48b, cause the back receiving part 48a
and the pressure receiving member 41 to retreat significantly. At
the time of retreat, the thin walls 48k of the bank parts 48b are
pressed backward by the right and left sides of the upper body of
the occupant (mainly shoulders, shoulder blades, franks, upper
arms, etc.) and the thin walls 48k of the bank parts 48b are bent
backward. The extending parts 41b of the pressure receiving member
41 are also pressed backward by the thin walls 48k and the
extending parts 41b are bent backward. The recesses 48g are formed
on the rear surfaces of the bank parts 48b. This indicates that a
space for retreating the thin walls 48k and the extending parts 41b
of the pressure receiving member 41 is disposed in front of the
rear surfaces of the bank parts 48b. This configuration can prevent
the bank parts 48b from reducing the backward sinking of the upper
body of the occupant.
[0231] A larger impulsive force moves the swing members 45a
backward against the tensile load of the tension springs 45d and
causes the pressure receiving member 41 to further retreat. With
the backward movement of the swing members 45a, the backward
displacement of the pressure receiving member 41 decreases toward
the upper portion and increases toward the lower portion.
[0232] As described above, the reinforcing cloth attaching members
52 deviate from the trajectory, drawn at a time of the retreat of
the pressure receiving member 41, of the left extending part 41b.
This configuration can prevent contact of the left extending part
41b with the reinforcing cloth attaching members 52, and thus
maintain proper retreat of the left extending part 41b and the
pressure receiving member 41. This ensures a desired retreating
distance of the pressure receiving member 41 and prevents the
reinforcing cloth attaching members 52 from reducing the backward
sinking of the upper body of the occupant.
[0233] The lower reinforcing cloth attaching member 52 is attached
to the side frame segment 40b at a position anterior to the front
edge 41b1 of the left extending part 41b. This configuration can
further prevent the lower reinforcing cloth attaching member 52
from reducing the retreat of the left extending part 41b and thus
can further ensure a desired retreating distance of the pressure
receiving member 41.
[0234] Although each extending part 41b has a larger backward
displacement in the lower direction, the vertical positions of the
reinforcing cloth attaching members 52 deviate from the lower edge
41b2 of the left extending part 41b. This configuration can further
prevent the reinforcing cloth attaching members 52 from reducing
the retreat of the left extending part 41b and thus can further
ensure a desired retreating distance of the pressure receiving
member 41.
[0235] The upper reinforcing cloth attaching member 52 is disposed
above the left extending part 41b and the lower reinforcing cloth
attaching member 52 is disposed below the left extending part 41b.
This configuration can further prevent the reinforcing cloth
attaching members 52 from reducing the retreat of the left
extending part 41b and thus can further ensure a desired retreating
distance of the pressure receiving member 41. This configuration
can further increase the degree of freedom in the shape of each
extending part 41b and thus can expand the extending part 41b. A
larger extending part 41b has a greater ability to laterally hold
the upper body of the occupant.
[0236] The reinforcing cloth attaching members 52 are attached to
the side frame segment 40b above or below the most forward
protruding portion 40b4 of the protrusion 40b3. This configuration
can further prevent the reinforcing cloth attaching members 52 from
reducing the retreat of the left extending part 41b. This
configuration can further increase the degree of freedom in the
shape of each extending part 41b and thus can expand the extending
parts 41b. A larger extending part 41b has a greater ability to
laterally hold the upper body of the occupant.
[0237] The front edge 41b1 of the right extending part 41b is
within the area 40d3, which is surrounded by the front end of the
side frame segment 40b and the side support member 40d. This
configuration can prevent contact of the right extending part 41b
with the side support member 40d at the backward deformation of the
right extending part 41b. This can ensure a desired retreating
distance of the pressure receiving member 41 and prevent the side
support member 40d from reducing the backward sinking of the upper
body of the occupant.
[0238] The reinforcing cloth attaching members 52, which are clips,
can be made smaller. Smaller reinforcing cloth attaching members 52
can prevent contact of the extending part 41b with the reinforcing
cloth attaching members 52 at the time of retreat of the pressure
receiving member 41.
[0239] The scope of the present invention should not be limited to
the above embodiment and various changes and modifications can be
made without departing from the spirit and scope of the present
invention. The following description focuses on several
modifications. These modifications are the same as the second
embodiment except for some changes. The following modifications may
be combined according to demand.
First Modification of Second Embodiment
[0240] In the second embodiment, the upper reinforcing cloth
attaching member 52 is attached to the side frame segment 40b above
the upper edge 41b3 of the left extending part 41b. In a first
modification, the upper reinforcing cloth attaching member 52 is
attached to the side frame segment 40b above the lower edge 41b2 of
the left extending part 41b and below the upper edge 41b3 of the
left extending part 41b while the pressure receiving member 41 is
in the natural state (See FIG. 18). In other words, the vertical
position of the upper reinforcing cloth attaching member 52 aligns
with that of the left extending part 41b. In this case, the beads
41b4 are formed at positions deviate upward or downward from the
upper reinforcing cloth attaching member 52. This configuration can
prevent contact of the beads 41b4 with the upper reinforcing cloth
attaching member 52 at the time of retreat of the left extending
part 41b.
Second Modification of Second Embodiment
[0241] In the second embodiment, one or two reinforcing cloth
attaching members 52 are attached to the left side frame segment
40b. In a second modification, three or more reinforcing cloth
attaching members 52 are used. Even in that case, any of the
reinforcing cloth attaching members 52 is attached to the side
frame segment 40b at a position deviating from the trajectory,
drawn at a time of a front-back movement of the pressure receiving
member 41, of the left extending part 41b.
Third Modification of Second Embodiment
[0242] In the second embodiment, the reinforcing cloth attaching
members 52 are clips made of resin. Each reinforcing cloth
attaching member 52 holds the hook 40b5 of the side frame segment
40b with the spiral structure 52a and the engaging portion 52c. In
contrast, a reinforcing cloth attaching member 53, used in place of
the reinforcing cloth attaching members 52, of a third modification
is a listing wire obtained by bending a wire rod, such as hard
steel wire, piano wire or stainless steel wire, as shown in FIGS.
19 to 22. The reinforcing cloth attaching member 53 includes a
support 53a, a pair of upper and lower arms 53b, and hooks 53c. The
support 53a extends vertically in left front of the side frame
segment 40b. The upper and lower arms 53b are bent backward at the
top end and bottom end of the support 53a and extend on the right
side (inside) and in front of the left side frame segment 40b. The
hooks 53c are each bent at the rear ends of the arms 53b into a
hook. The reinforcing cloth attaching member 53 is attached to the
side frame segment 40b, in particular, to the main body part 40b2
of the side frame segment 40b via a latching member 54 made of
metal. The latching member 54 is welded to the rear end of the left
side frame segment 40b, in particular, to the main body part 40b2
of the side frame segment 40b, and protrudes rightward from the
side frame segment 40b. A portion, protruding rightward from the
side frame segment 40b, of the latching member 54 is formed into a
gate (for example, angular U-shape or a U-shape). The hooks 53c of
the reinforcing cloth attaching member 53 are hooked or tangled by
the gate-shaped portion of the latching member 54. The rear ends of
the arms 53b are thereby attached to the left side frame segment
40b via the latching member 54. Alternatively, the hooks 53c of the
reinforcing cloth attaching member 53 may be directly hooked by the
right side (inside) of the rear end of the left side frame segment
40b to attach the rear ends of the arms 53b to the left side frame
segment 40b.
[0243] The reinforcing cloth 51, which is in a tension state, is
stretched from the planned rupture portion 49t to a support 53a of
the reinforcing cloth attaching member 53 via the periphery of the
airbag module 50. The reinforcing cloth 51 has other end 51b folded
back and sewed at the support 53a to form the other end 51b into a
cylinder. The support 53a is inserted through the cylinder. The
other end 51b of the reinforcing cloth 51 is thereby hooked to the
support 53a.
[0244] The reinforcing cloth attaching member 53 is disposed at a
position deviating from the trajectory, drawn at a time of a
front-back movement of the pressure receiving member 41, of the
left extending part 41b. This can prevent the reinforcing cloth
attaching member 53 from reducing the retreat of the left extending
part 41b.
[0245] In lateral view, the reinforcing cloth attaching member 53
is provided so as to avoid the beads 41b4. In other words, arms 53b
are disposed above or below the beads 41b4 in lateral view. This
configuration can prevent contact of the beads 41b4 with the
reinforcing cloth attaching member 53 at the time of retreat of the
left extending part 41b.
[0246] In lateral view, the upper arm 53b is disposed above the
lower edge 41b2 of the extending part 41b. The lower arm 53b is
disposed below the lower edge 41b2 of the extending part 41b. This
configuration can further prevent the reinforcing cloth attaching
member 53 from reducing the retreat of the left extending part
41b.
[0247] The reinforcing cloth attaching member 53 is disposed above
a most forward protruding portion 40b4 of a protrusion 40b3. This
configuration can further prevent the reinforcing cloth attaching
member 53 from reducing the retreat of the left extending part
41b.
Fourth Modification of Second Embodiment
[0248] The structure of the above mentioned seat 1A may be
left-right reversed. In other words, a seat obtained by
mirror-reversing the above mentioned seat 1A may be used.
Additional Statement on Second Embodiment
[0249] As is evident from the above description of the second
embodiment and its modifications, the description of the second
embodiment and its modifications includes various disclosures on
technical ideas in addition to the aspect of the invention
described in the following notes.
Note 1.
[0250] A seat backrest including:
[0251] left and right side frame segments disposed in parallel in
the right-left direction;
[0252] a pressure receiving member disposed between the side frame
segments, the pressure receiving member being movable in a
front-back direction;
[0253] an airbag module mounted on a side frame segment of the side
frame segments;
[0254] a cushion pad covering front surfaces of the side frame
segments and a front surface of the pressure receiving member;
[0255] a skin covering the cushion pad;
[0256] a reinforcing cloth attaching member attached to the side
frame segment; and
[0257] a reinforcing cloth stretching from a back of the skin to
the reinforcing cloth attaching member via a periphery of the
airbag module,
[0258] wherein the pressure receiving member includes: [0259] a
main body part; and [0260] right and left extending parts extending
rightward and leftward from right and left sides of the main body
part,
[0261] wherein the reinforcing cloth attaching member is provided
at a position deviating from a trajectory of each extending part,
the trajectory being drawn at a time of front-back moving of the
pressure receiving member.
Note 2.
[0262] The seat backrest according to note 1, wherein the
reinforcing cloth attaching member is disposed anterior to the
front edge of an extending part of the extending parts.
Note 3.
[0263] The seat backrest according to note 1 or 2, wherein
[0264] each extending part inclines upward toward the back, and
[0265] the reinforcing cloth attaching member is disposed above or
below a lower edge of the extending part.
Note 4.
[0266] The seat backrest according to one of notes 1 to 3, wherein
the reinforcing cloth attaching member is disposed either above or
below the extending part or both above and below the extending
part.
Note 5.
[0267] The seat backrest according to one of notes 1 to 3,
wherein
[0268] a bead is formed on each extending part,
[0269] a vertical position of the reinforcing cloth attaching
member aligns with a vertical position of each extending part,
and
[0270] the reinforcing cloth attaching member is disposed above or
below the bead.
Note 6.
[0271] The seat backrest according to note 1, wherein
[0272] a bead is formed in each extending part,
[0273] the reinforcing cloth attaching member is a wire rod
including a support and a pair of upper and lower arms, the support
extending vertically in front of one of the side frame segments and
over which the reinforcing cloth is to be covered, and the pair of
upper and lower arms bending backward at a top end and a bottom end
of the support, extending in front of and inside of the side frame
segment, and having rear ends attached to the side frame segment;
and the arms are disposed above or below the bead.
Note 7.
[0274] The seat backrest according to one of notes 1 to 6,
wherein,
[0275] A protrusion protruding forward is formed in the side frame
segment, and
[0276] the reinforcing cloth attaching member is disposed above or
below a most forward protruding portion of the protrusion.
Note 8.
[0277] The seat backrest according to one of notes 1 to 7, further
including a side support member attached to a front end of a side
frame segment of the side frame segments, wherein
[0278] the side support member includes a vertical section and a
bent section, the vertical section vertically extending away from a
front surface of the side frame segment, and the bent section being
bent backward at an end of the vertical section and fixed to a
front end of the side support member, and
[0279] wherein, in lateral view, a front edge of the extending part
is disposed in an area between the front surface of the side frame
segment and the vertical section.
Note 9.
[0280] The seat backrest according to one of notes 1 to 6,
wherein,
[0281] A protrusion protruding forward is formed in the side frame
segment,
[0282] the reinforcing cloth attaching member is a clip, and
[0283] the reinforcing cloth attaching member is disposed below a
most forward protruding portion of the protrusion.
(a) Advantageous Effects of Present Invention Described in Note
1
[0284] The present invention described in Note 1 can prevent
contact of the extending parts with the reinforcing cloth attaching
members at the time of retreat of the pressure receiving member,
and thus can maintain proper retreat of the pressure receiving
member. This ensures a desired retreating distance of the pressure
receiving member and can maintain proper backward sinking of the
upper body of the occupant.
(b) Advantageous Effects of Present Invention Described in Notes 2,
3 and 4
[0285] The present invention according to notes 2, 3 and 4 can
further prevent contact of each extending part with the reinforcing
cloth attaching members. It can maintain further proper retreat of
the pressure receiving member. This ensures a desired retreating
distance of the pressure receiving member.
(c) Advantageous Effects of Present Invention Described in Note
4
[0286] The present invention described in Note 4 increases the
degree of freedom in the shape of each extending part. The
reinforcing cloth attaching members, which are disposed both above
and below the extending part, allow a stable attachment of the
reinforcing cloth.
(d) Advantageous Effects of Present Invention Described in Note
5
[0287] The present invention described in Note 5 can prevent
contact of the beads with the reinforcing cloth attaching member
and thus can maintain proper retreat of the pressure receiving
member. The beads enhance the rigidity of each extending part.
(e) Advantageous Effects of Present Invention Described in Note
6
[0288] The present invention described in Note 6 can prevent
contact of the beads with the arms of the reinforcing cloth
attaching member and thus can maintain proper retreat of the
pressure receiving member. This ensures a desired retreating
distance of the pressure receiving member. The beads enhance the
rigidity of each extending part.
(f) Advantageous Effects of Present Invention Described in Note
7
[0289] The present invention described in Note 7 can prevent
contact of the extending part with the reinforcing cloth attaching
member and thus can maintain proper retreat of the pressure
receiving member. This can increase the degree of freedom in the
shape of the extending part.
(g) Advantageous Effects of Present Invention Described in Note
8
[0290] The present invention described in Note 8 can prevent
contact of the extending part with the side support member and thus
can maintain proper retreat of the pressure receiving member. This
ensures a desired retreating distance of the pressure receiving
member and can maintain proper backward sinking of the upper body
of the occupant.
(h) Advantageous Effects of Present Invention Described in Note
9
[0291] The present invention described in Note 9 can prevent
contact of the extending part with the reinforcing cloth attaching
member and thus can maintain proper retreat of the pressure
receiving member. This increases the degree of freedom in the shape
of the extending part and can reduce the size of the reinforcing
cloth attaching member, which is a clip.
Third Embodiment
[0292] FIG. 23 is a perspective view of a seat 1B according to the
third embodiment of the present invention. FIG. 24 is a perspective
view of a seat frame of the seat 1B. The same parts between the
seat 1B according to the third embodiment and the seat 1 according
to the first embodiment are given the same reference numerals. If
the same parts are provided in the same manner, the explanation
thereof will be omitted if possible. The following description
focuses on differences between the seat 1B according to the third
embodiment and the seat 1 according to the first embodiment.
[0293] The seat 1B is also a vehicle seat, in particular an
automotive seat. Similarly to the seat 1 according to the first
embodiment, the seat 1B includes slide rails 2, a bottom seat 3, a
backrest 4, a recliner mechanism 5, and a headrest 6. The slide
rails 2, the bottom seat 3, the recliner mechanism 5, and the
headrest 6 of the seat 1B of the third embodiment are provided in
the same manner as the slide rails 2, the bottom seat 3, the
recliner mechanism 5, and the headrest 6 of the seat 1 according to
the first embodiment. The backrest 4 in the seat 1B according to
the third embodiment is different from that in the seat 1 according
to the first embodiment.
[0294] FIG. 25 is a front view of the backrest 4 of the seat 1B
according to the third embodiment. FIG. 25 illustrates a cushion
pad 48 of the backrest 4 with a two-dot chain lines to illustrate
the inside of the backrest 4. FIG. 26 is a cross sectional view
taken along line XXVI-XXVI in FIG. 25, viewed in the direction of
arrows.
[0295] As shown in FIGS. 23 to 26, the backrest 4, similarly to the
first embodiment, includes a backrest frame 40, a pressure
receiving member 41, a cross member 42, a cushion pad 48 and a skin
49. The backrest 4 according to the first embodiment includes the
upper wire rod 43 and the lower wire rod 44, while the backrest 4
according to the third embodiment includes a coupling wire rod 60.
The coupling wire rod 60 will be described in detail later.
[0296] The backrest frame 40 according to the third embodiment is
provided in the same manner as that according to the first
embodiment.
[0297] The pressure receiving member 41 according to the third
embodiment is provided in the same manner as that according to the
first embodiment, except for claws 41f. The claws 41f are provided
on the pressure receiving member 41 in place of the claws 41c and
41d in association with the provision of the coupling wire rod 60
inside the backrest 4 in the third embodiment. The positions of the
claws 41f differ from those of the claws 41c and 41d. The claws 41f
will be described in detail later.
[0298] The cross member 42 according to the first embodiment is a
meandrous rod member. In contrast, the cross member 42 according to
the third embodiment is a metal sheet. The cross member 42 extends
in the right-left direction. The cross member 42 has the left end
fixed to a left vertical pipe segment 40b1 by welding. The cross
member 42 has the right end fixed to a right vertical pipe segment
40b1 by welding. The cross member 42 bridges the right and left
vertical pipe segments 40b1.
[0299] The coupling wire rod 60 will now be described in detail.
The coupling wire rod 60 is bent into a substantially U shape. The
coupling wire rod 60 includes right and left vertical wire segments
61 and a horizontal wire segment 62. The vertical wire segments 61
extend vertically. The horizontal wire segment 62 extends in the
right-left direction to couple the lower ends of the vertical wire
segments 61. Each of the right and left vertical wire segments 61
includes a bent segment 63. The bent segment is convex toward the
inside of the backrest frame 40, i.e., the center in the right-left
direction of the backrest frame 40.
[0300] In front or rear view of the pressure receiving member 41,
the coupling wire rod 60 according to this embodiment is put across
the backrest frame 40 so as to avoid the front edges (front ends or
ends of extending parts) 41b1 of the extending parts 41b. More
specifically, the coupling wire rod 60 is coupled to the backrest
frame 40 by multiple wire catching parts 42a and 40c1. The wire
catching parts 42a are provided on the cross member 42. The wire
catching parts 40c1 are provided on a lower frame segment 40c. The
wire catching parts 42a are formed by partially cutting, raising
and bending the cross member 42. The wire catching parts 40c1 are
formed by partially cutting, raising and bending the lower frame
segment 40c. The horizontal wire segment 62, which is the lower
portion of the coupling wire rod 60, is caught by the wire catching
parts 40c1. The right and left vertical wire segments 61 of the
coupling wire rod 60 has top ends caught by the wire catching parts
42aa on the cross member 42. The right and left vertical wire
segments 61 thereby vertically bridge the cross member 42 and the
lower frame segment 40c. The coupling wire rod 60 may be coupled to
the backrest frame 40 by welding.
[0301] Multiple claws 41f for fixing the pressure receiving member
41 to the coupling wire rod 60 are provided on the main body part
41a of the pressure receiving member 41. The claws 41f are
integrated with the pressure receiving member 41. Multiple (for
example, three) claws 41f are disposed vertically on the left part
of the main body part 41a. Remaining multiple (for example, three)
claws 41f are disposed vertically on the right part of on the right
side of the main body part 41a. As shown in FIG. 26, each claw 41f
protrudes backward from the rear surface of the main body part 41a
and is formed into a substantially U or J shape in top or bottom
view. More specifically, each claw 41f protrudes backward from the
rear surface of the main body part 41a, is bent rightward or
leftward, extends from the bend along the rear surface of the main
body part 41a, is bent frontward, and extends from the deformation
toward the rear surface of the pressure receiving member 41. Once
the coupling wire rod 60, in particular, a bent segment 63 of each
vertical wire segment 61 is hooked to the claws 41f, the claws 41f
hold the vertical wire segments 61, while catching the vertical
wire segments 61 between the claws 41f and the rear surface of the
main body part 41a. The portions at which the coupling wire rod 60
is hooked to the claws 41f are the coupling portions between the
coupling wire rod 60 and the pressure receiving member 41. In this
embodiment, the claws 41f are formed on the main body part 41a.
This indicates that the coupling portions of the coupling wire rod
60 and the pressure receiving member 41 lie on the main body part
41a, not on the right and left extending parts 41b.
[0302] As shown in FIG. 25, the bent portions 63 of the coupling
wires 60 are bent away from the extending parts 41b. The vertical
positions of the extending parts 41b are within a range 63r. The
range 63r extends from the upper end 63a to the lower end 63b of
each bent segment 63. This indicates that, at the height of the
extending parts 41b, the coupling wire rod 60 (vertical wire
segments 61) extends not through the extending parts 41b but
through the main body part 41a. The coupling wire rod 60 is
disposed such that, in front or rear view, it deviates rightward
and leftward from the front edges 41b1 of the extending parts 41b
and, in front view, the front edges 41b1 of the extending parts 41b
do not overlap with the coupling wire rod 60.
[0303] Similarly to the first embodiment, each extending part 41b
can resiliently bend and deform in the front-back direction along
the connecting line between the extending part 41b and the main
body part 41a so that the extending part 41b can follow the elastic
deformation of the bank part 48b when an occupant leans against the
backrest 4. Each extending part 41b is formed such that the moving
trajectory 41z of the front edge 41b1 drawn at a time of the
deformation of the extending part 41b lies inside of the front part
of the main body part 40b2 of the side frame segment with respect
to the right-left direction.
[0304] At rear-end collision by another vehicle (with the
above-mentioned seat 1B mounted), the upper body of an occupant is
pressed against the cushion pad 48 to significantly deform the
near-center portion of the cushion pad 48. If the impulsive force
is so large that a backward load exceeding a predetermined value is
applied to the pressure receiving member 41 by the upper body of
the occupant via the cushion pad 48, the vertical wire segments 61
of the coupling wire rod 60 mainly bend or deform. In response to
the bend or deformation, the pressure receiving member 41 retreats
relative to the main body parts 40b2 of the left and right side
frame segments and the upper body of the occupant deeply sinks into
the backrest 4. As a result, the head of the occupant rapidly
approaches the headrest 6 and is supported thereby, thus protecting
the head and the neck region of the occupant from the impact of the
rear-end collision by the vehicle.
[0305] Advantageous effects of the seat 1B with such a
configuration will now be described.
[0306] As shown in FIG. 25, the pressure receiving member 41 of the
seat 1B has the main body part 41a and the right and left extending
parts 41b. This configuration allows the seat 1B to support a wide
range of the upper body of the occupant with the central main body
part 41a and the right and left extending parts 41b. This
configuration also leads to a stable support of the upper body of
the occupant. The coupling wire rod 60 is disposed such that it
does not overlap with the front edges 41b1 of the extending parts
41b in front view. This configuration can prevent the interference
between the front edges 41b1 of the extending parts 41b and the
coupling wire rod 60 at the time of an anteroposterior movement of
the front edges 41b1 due to deformation of the extending parts 41b,
as shown in FIG. 26.
[0307] In the third embodiment, the coupling wire rod 60 lies
vertically as a bridge, as shown in FIG. 25. The configuration of
bridging the coupling wire vertically can achieve a disposition
that avoids the overlap of the front edges 41b1 of the extending
parts 41b with the coupling wire rod 60 more efficiently than a
configuration of bridging the coupling wire in the right-left
direction.
[0308] In the third embodiment, the vertical positions of the
extending parts 41b are within the range 63r, which extends from
the upper end 63a to the lower end 63b of the bent segment 63. This
indicates that the coupling wire rod 60 at the height of the
extending parts 41b are entirely away from the front edges 41b1
inward in the right-left direction. This configuration can prevent
the interference between the front edges 41b1 and the coupling wire
rod 60 efficiently.
[0309] In the third embodiment, the coupling portions between the
coupling wire rod 60 and the pressure receiving member 41 (claws
41f) are on the main body part 41a. This indicates that the
coupling wire rod 60 is disposed such that it is caught by the
claws 41f, which are disposed away from the front edges 41b1. This
disposition can also prevent the interference between the front
edges 41b1 and the coupling wire rod 60 effectively. No allocation
of the coupling wire rod 60 in the vicinity of the extending parts
41b can prevent the coupling wire rod 60 from reducing the
deformation of the extending parts 41b.
[0310] In the third embodiment, the moving trajectory 41z of the
front edge 41b1 drawn at a time of the deformation of the extending
part 41b lies inside of the front part of the main body part 40b2
of the side frame segment with respect to the right-left direction.
This can prevent the interference between the front edges 41b1 and
the main body parts 40b2 of the side frame segment at the time of
an anteroposterior movement of the front edges 41b1.
[0311] The third embodiment of the present invention has been
described above. The embodiments applicable to the present
invention should not be limited to those described above and may be
modified as appropriate within the scope of the present invention.
The following description focuses on several modifications of the
third embodiment. These modifications are the same as the third
embodiment except for some changes. The following modifications may
be combined according to demand.
First Modification of Third Embodiment
[0312] In the third embodiment, the vertical positions of the
extending parts 41b are entirely within the range 63r, which
extends from the upper end 63a to the lower end 63b of the bent
segment 63 of the coupling wire rod 60, as shown FIG. 25, but the
present invention should not be limited to this configuration. For
example, as shown in FIG. 27, the extending parts 41b may be formed
such that the vertical positions of the extending parts 41b are
partially within the range 63r, which extends from the upper end
63a to the lower end 63b of the bent segment 63. Even in this
configuration, a portion of the coupling wire rod 60 at the height
of the extending parts 41b is partially away from the left and
right front edges 41b1 inward in the right-left direction. This
configuration can prevent the interference between the front edges
41b1 and the coupling wire rod 60.
Second Modification of Third Embodiment
[0313] In the third embodiment, the coupling portions (claws 41f)
of the coupling wire rod 60 and the pressure receiving member 41
are on main body part 41a, as shown in FIG. 25, but the present
invention should not be limited to this configuration. For example,
the claws 41f may be on the extending parts 41b. The coupling
between the coupling wire rod 60 and the pressure receiving member
41 should not be limited to the use of the claws 41f. For example,
pairs of through-holes are disposed in a row in the right-left
direction or in the up-down direction on the pressure receiving
member 41 and the coupling wire rod 60 is fixed with ties extending
through the through-holes.
Third Modification of Third Embodiment
[0314] In the third embodiment, the coupling wire rod 60 (vertical
wire segments 61) vertically bridges the cross member 42 and the
lower frame segment 40c, but the present invention should not be
limited to this configuration. For example, with reference to FIG.
25, the coupling wire may bridge the main body parts 40b2 of the
left and right side frame segments in the right-left direction. The
coupling wire may diagonally bridge either of the main body parts
40b2 of the side frame segments and the cross member 42 or the
lower frame segment 40c.
Fourth Modification of Third Embodiment
[0315] In the third embodiment, the extending parts 41b are formed
only at positions corresponding to the breast height of the
occupant, but the present invention should not be limited to this
configuration. For example, the extending parts 41b may be formed
only at positions corresponding to the waist height of the
occupant. Extending parts other than the extending parts 41b formed
at the breast-height positions of the occupant may be formed at the
waist-height positions of the occupant. If both the breast-height
extending parts and the waist-height extending parts are provided,
they may be formed independently or coupled with each other.
Modification 5 of Third Embodiment
[0316] In the third embodiment, the moving trajectory 41z of the
front edge 41b1 drawn at a time of the deformation of the extending
part 41b lies inside of the front part of the main body part 40b2
of the side frame segment with respect to the right-left direction,
as shown in FIG. 26. This configuration prevents the interference
between the front edges 41b1 and the main body parts 40b2 of the
side frame segments, but the present invention should not be
limited to this configuration. For example, the extending parts 41b
may be formed such that the front edges 41b1 come into contact with
the main body parts 40b2 of the side frame segments at the time of
deformation of a predetermined amount. Such a configuration can
prevent excess deformation of the extending parts 41b.
Sixth Modification of Third Embodiment
[0317] The coupling wire rod 60 according to the third embodiment
may be adopted for the seat 1A according to the second embodiment.
The coupling wire rod 60 may be adopted in place of the upper and
lower wire rods 43 and 44 according to the second embodiment.
Additional Statement on Third Embodiment
[0318] As is evident from the above description of the third
embodiment and its modifications, the description of the third
embodiment and its modifications include various disclosures of
technical ideas in addition to the aspect of the invention shown in
the following notes.
Note 1.
[0319] A vehicle seat having a bottom seat and a backrest,
including:
[0320] a backrest frame constituting part of the backrest;
[0321] a coupling wire rod put across the backrest frame; and
[0322] a plate-like pressure receiving member coupled to the
backrest frame via the coupling wire rod and supporting load from
an occupant,
[0323] wherein the pressure receiving member includes a main body
part and extending parts, the main body part facing a rear surface
of an upper body of the occupant and the extending parts extending
from right and left edges of the main body part outward in the
right-left direction and being resiliently deformable in the
front-back direction, and
[0324] wherein the extending parts and the coupling wire rod are
disposed such that front edges of the extending parts do not
overlap with the coupling wire rod in front view.
Note 2.
[0325] The vehicle seat according to note 1, wherein the coupling
wire rod lies vertically.
Note 3.
[0326] The vehicle seat according to note 2, wherein
[0327] the coupling wire rod includes bent segments, each segment
is convex inward in the right-left direction and
[0328] wherein a vertical position of each extending part is at
least partially within a range between an upper end and a lower end
of the bent segment.
Note 4.
[0329] The vehicle seat according to note 3, wherein the vertical
position of each extending part is within a range between the upper
end and the lower end of the bent segment.
Note 5.
[0330] The vehicle seat according to one of notes 1 to 4, wherein
coupling portions between the coupling wire rod and the pressure
receiving member are on the main body part.
Note 6.
[0331] The vehicle seat according to one of notes 1 to 5, wherein
the backrest frame includes right and left side frame segments
constituting right and left frames of the backrest, and
[0332] wherein each extending part is formed such that a moving
trajectory of a front edge of the extending part drawn at a time of
deformation of the extending part lies inside of the side frame
segment with respect to a right-left direction.
(a) Advantageous Effects of Present Invention Described in Note
1
[0333] The central main body part and the right and left extending
parts can support a wide range of the upper body of the occupant.
This configuration can stabilize the support of the upper body of
the occupant. The coupling wire rod does not overlap with the front
edges of the extending parts in front view. Such a configuration
can prevent the interference between the front edges of the
extending parts and the coupling wire rod at the time of an
anteroposterior movement of the front edges due to deformation of
the extending parts.
(b) Advantageous Effects of Present Invention Described in Note
2
[0334] The present invention described in Note 2 can achieve a
disposition that avoids the overlap of the front edges of the
extending parts with the coupling wire rod in front view more
efficiently than a configuration of bridging the coupling wire rod
in the right-left direction. Such a configuration can prevent the
interference between the front edges of the extending parts and the
coupling wire rod.
(c) Advantageous Effects of Present Invention Described in Note
3
[0335] A portion of the coupling wire rod at the height of the
extending parts is at least partially away from the left and right
front edges inward in the right-left direction. This configuration
can prevent the interference between the front edges and the
coupling wire rod efficiently.
(d) Advantageous Effects of Present Invention Described in Note
4
[0336] A portion of the coupling wire rod at the height of the
extending parts is entirely away from the front edges of the
extending parts inward in the right-left direction. This
configuration can prevent the interference between the front edges
and the coupling wire rod more efficiently.
(e) Advantageous Effects of Present Invention Described in Note
5
[0337] Coupling points are disposed remote from the front edges of
the extending parts, thus further preventing the interference
between the front edges of the extending parts and the coupling
wire rod efficiently. This, in turn, indicates that no disposition
of the coupling portions in the vicinity of the extending parts can
prevent the coupling wire rod from reducing the deformation of the
extending parts.
(f) Advantageous Effects of Present Invention Described in Note
6
[0338] The present invention described in Note 6 can prevent the
interference between the front edges of the extending parts and the
side frame segments even at the time of an anteroposterior movement
of the front edges due to deformation of the extending parts.
Fourth Embodiment
[0339] FIG. 28 is a perspective view of a seat 1C according to the
fourth embodiment of the present invention. FIG. 29 is a
perspective view of a seat frame of the seat 1C. The same parts
between the seat 1C according to the fourth embodiment and the seat
1 according to the first embodiment are given the same reference
numerals. If the same parts are provided in the same manner, the
explanation thereof will be omitted if possible. The following
description focuses on differences between the seat 1C according to
the fourth embodiment and the seat 1 according to the first
embodiment.
[0340] The seat 1C is also a vehicle seat, in particular an
automotive seat. Similarly to the seat 1 according to the first
embodiment, the seat 1C includes slide rails 2, a bottom seat 3, a
backrest 4, a recliner mechanism 5 and a headrest 6. The slide
rails 2, the bottom seat 3, the recliner mechanism 5 and the
headrest 6 of the seat 1C according to the fourth embodiment are
provided in the same manner as those of the seat 1 according to the
first embodiment. The backrest 4 of the seat 1C according to the
fourth embodiment is different from that of the seat 1 according to
the first embodiment.
[0341] FIG. 30 is a front view of the backrest 4 of the seat 1B
according to the third embodiment. FIG. 30 illustrates the cushion
pad 48 of the backrest 4 with a two-dot chain lines to show the
internal structure of the backrest 4. FIG. 31 is a cross sectional
view taken along line XXVI-XXVI in FIG. 25, viewed in the direction
of arrows.
[0342] Similarly to the first embodiment, the backrest 4 includes a
backrest frame 40, a pressure receiving member 41, a cross member
42, an upper wire rod 43, a lower wire rod 44, swing members 45a,
tension springs 45d, stoppers, a cushion pad 48, and a skin 49, as
shown in FIGS. 28 to 31. The backrest frame 40, the pressure
receiving member 41, the cross member 42, the upper wire rod 43,
the lower wire rod 44, swing members 45a, tension springs 45d, the
stoppers, the cushion pad 48 and the skin 49 according to the third
embodiment are provided in a similar manner to the backrest frame
40, the pressure receiving member 41, the cross member 42, the
upper wire rod 43, the lower wire rod 44, swing members 45a,
tension springs 45d, stoppers 45b and 45c, the cushion pad 48 and
the skin 49 according to the first embodiment.
[0343] The backrest 4 according to the third embodiment includes
two main body airbags (pressure receiving airbags) 71 and 72
functioning as support position adjusters. The main body airbags 71
and 72 are disposed on the pressure receiving member 41. As shown
in FIG. 31, the main body airbags 71 and 72 inflate and deform the
cushion pad 48 such that it protrudes forward (details are given
later). The inflated main body airbags 71 and 72 deflate and deform
the protruding cushion pad 48 such that it gets dented. This
enables adjustment of a support position of an occupant seated on
the seat 1C in accordance with the amount of protrusion of the main
body airbags 71 and 72.
[0344] The main body airbag 71 is formed by bonding together two
sheet members made of resin by welding. The main body airbag 71
includes an air chamber 71a containing gas, such as air. The main
body airbag 72 is also formed in a similar manner to the main body
airbag 71 and includes an air chamber 72a.
[0345] The air chamber 71a is formed by bonding together two sheet
members into a substantially U shape. In front view, the air
chamber 71a has an upper edge which is concave toward the
horizontal center of the upper edge. This is also applied to the
air chamber 72a.
[0346] The main body airbag 71 overlaps with the main body airbag
72 such that the main body airbag 71 is in front of the main body
airbag 72 and the main body airbag 72 is in rear of the main body
airbag 71. The main body airbags 71 and 72 are attached to the
front surface of the main body part 41a below claws 41c with two
pin-shaped clips 70 at the upper edges of the airbags 71 and 72,
while they are overlapped with each other.
[0347] The main body airbag 72 in back is vertically longer than
the main body airbag 71. The air chamber 72a deviates downward from
the air chamber 71a such that the lower end portion of the air
chamber 71a overlaps with the upper end portion of the air chamber
72a in the front-back direction while the main body airbags 71 and
72 are attached to the main body part 41a.
[0348] The upper end portion of the air chamber 71a of the main
body airbag 71, placed in front, is at the same height as the right
and left extending parts 41b. In other words, the right and left
extending parts 41b according to this embodiment, which extend
diagonally forward to the outward in the right-left direction, are
formed such that the lower edges of the extending parts 41b are
disposed within a vertical range of the air chamber 71a of the main
body airbag 71. This allows the upper portion of the air chamber
71a of the main body airbag 71 to be disposed between the right and
left extending parts 41b, in particular, at the time of inflation
of the air chamber 71a. This configuration enables the right and
left extending parts 41b to prevent a right-left movement of the
main body airbag 71.
[0349] One end of a hose 73 for feeding gas to the air chamber 71a
is coupled to the upper end portion of the air chamber 71a of the
main body airbag 71. One end of a hose 74 for feeding gas to the
air chamber 72a is coupled to the upper end portion of the air
chamber 72a of the main body airbag 72.
[0350] As shown in FIG. 29, the hose 73 is routed behind the
pressure receiving member 41 and the right side frame 40b. Other
end of the hose 73 is coupled to a control unit 75. This is also
applied to the hose 74.
[0351] The control unit 75 is fixed to the outer surface of the
lateral side of the right side frame 40b. The control unit 75 is
connected to a pump 87, which is fixed to a bottom seat frame 30,
via a hose 76.
[0352] The pump 87 is an apparatus for feeding gas to the main body
airbags 71 and 72. The control unit 75 is an apparatus to adjust
the amount of inflation of the main body airbags 71 and 72 (air
chambers 71a and 72a). The control unit 75 includes a valve unit
with a variable opening (not shown), a relief valve (not shown),
and a controller board (not shown) for controlling the degree of
opening of the valve unit. The valve unit is closed during a normal
operation.
[0353] An operator manipulates a controller (not shown) to open the
valve unit of the control unit 75. The pump 87 feeds gas to the
main body airbags 71 and 72. The main body airbags 71 and 72 are
then inflated, as shown in FIG. 31. The inflation of the main body
airbags 71 and 72 deforms a back receiving part 48a of the cushion
pad 48 such that it protrudes forward.
[0354] Pressure is applied from the occupant to the main body
airbags 71 and 72 via the back receiving part 48a while the valve
unit of the control unit 75 remains opened after the manipulation
of the controller by the occupant. The main body airbags 71 and 72
are deflated to deform the back receiving part 48a of the cushion
pad 48 such that an inflated back receiving part 48a gets dented.
The main body airbags 71 and 72 may be deflated through the
discharge of gas from the main body airbags 71 and 72 through the
pump 87.
[0355] Once the operator manipulates the controller to close the
valve unit of the control unit 75, the state of the inflated main
body airbags 71 and 72 is kept.
[0356] As shown above, the state of the inflated main body airbags
71 and 72 (extent of deformation of the back receiving part 48a of
the cushion pad 48) is adjusted through the manipulation of the
controller by the occupant who opens or closes the valve of the
control unit 75 or starts or stops the pump 87. This enables the
adjustment of the anteroposterior position of supporting the
occupant. The two main body airbags 71 and 72 may be configured
such that the state of the inflation can be separately or
dependently adjusted.
[0357] At rear-end collision by another vehicle (with the
above-mentioned the seat 1C mounted), the upper body of an occupant
is pressed against the cushion pad 48 to significantly deform the
near-center portion of the cushion pad 48. If the impulsive force
is so large that a backward load exceeding a predetermined value is
applied to the pressure receiving member 41 by the upper body of
the occupant via the cushion pad 48, the upper and lower wire rods
43 and 44 bend or the lower wire rod 44 moves backward due to the
movement of each swing member 45a. This causes the pressure
receiving member 41 to retreat relative to the left and right side
frame segments 40b and the upper body of the occupant to deeply
sink into the backrest 4. As a result, the head of the occupant
rapidly approaches the headrest 6 and is supported thereby, thus
protecting the head and the neck region of the occupant from the
impact of the rear-end collision by the vehicle.
[0358] Advantageous effects of the seat 1C with such a
configuration will now be described.
[0359] The pressure receiving member 41 of the seat 1C, which
includes the main body part 41a and the right and left extending
parts 41b, can support a wide range of the upper body of the
occupant with the central main body part 41a and the right and left
extending parts 41b via the cushion pad 48. This configuration can
stabilize the support of the upper body of the occupant.
[0360] The right and left extending parts 41b according to this
embodiment, which extend diagonally forward toward the outside in
the right-left direction, can prevent a right-left movement
(displacement) of the main body airbag 71, which is disposed in
front of the main body part 41a. This configuration can stabilize
the support of the upper body of the occupant.
[0361] In this embodiment, the claws 41c are disposed within the
vertical range of the extending parts 41b. This allows the pressure
receiving member 41 to be coupled to the backrest frame 40 via the
upper wire rod 43 at the height of the extending parts 41b. This
enables the extending parts 41b and the main body part 41a at the
height of the extending parts 41b to receive load from the occupant
efficiently, leading to a more stable support of the upper body of
the occupant.
[0362] The fourth embodiment of the present invention has been
described above. The embodiments applicable to the present
invention should not be limited to those described above and may be
modified as appropriate within the scope of the present invention.
The following description focuses on several modifications of the
fourth embodiment. These modifications are the same as the fourth
embodiment except for some changes. The following modifications may
be combined according to demand.
First Modification of Fourth Embodiment
[0363] FIG. 32 is a perspective view of a backrest frame 40 of a
backrest 4 according to a first modification of the fourth
embodiment. As shown in FIG. 32, the backrest 4 includes the main
body airbags 71 and 72 and right and left extending part airbags
(support airbags) 77R and 77L as support position adjusters.
[0364] The left extending part airbag 77L inflates and deflates to
deform the left bank part 48b of the cushion pad 48 (see FIG. 34).
Similarly to the main body airbags 71 and 72, the left extending
part airbag 77L is formed by bonding together two sheet members. As
shown in FIG. 33, the left extending part airbag 77L includes a
left air chamber 77La containing gas, such as air. This is also
applied to the right extending part airbag 77R. The right extending
part airbag 77R deforms the right bank part 48b of the cushion pad
48 and includes a right air chamber 77Ra.
[0365] In front view, the left air chamber 77La has a contour 77Lb
on the right edge thereof (horizontally inside). The contour 77Lb
is curved into an arch (substantially U-shape). The arch is dented
toward the left (horizontally outside) at the center in the
vertical direction. In other words, the left air chamber 77La is
formed by bonding together two sheet members. The two sheet members
have a contour 77Lb on the right side thereof (horizontally
inside). The contour 77Lb is curved into an arch (substantially
U-shape). The arch is dented toward the left side (horizontally
outside) at the center in the vertical direction. The right
extending part airbag 77R is provided symmetrically with the left
extending part airbag 77L.
[0366] The left extending part airbag 77L is attached to the front
surface of the left extending part 41b at the top end and the
bottom end of the horizontally inside edge of the left extending
part airbag 77L with pin-shaped clips 79L. The right extending part
airbag 77R is attached to the front surface of right extending part
41b in a similar manner with clips 79R.
[0367] In front view, the extending part airbags 77L and 77R and
the main body airbags 71 and 72 are disposed apart from each
other.
[0368] The air chambers 77La and 77Ra of the extending part airbags
77L and 77R have the upper ends connected to one ends of hoses 78L
and 78R. The hoses 78L and 78R extend from the extending part
airbags 77L and 77R to a control unit 75 through the rear surface
of the right side frame 40b. The other ends of the hoses 78L and
78R are jointed to each other and connected to the control unit
75.
[0369] An operator manipulates a controller to open a valve unit of
the control unit 75. A pump, for example, the pump 87, feeds gas to
the extending part airbags 77L and 77R. The extending part airbags
77L and 77R inflate, as shown in FIG. 34. The inflation of the
extending part airbags 77L and 77R deforms the bank parts 48b of
right and left the cushion pad 48 such that the bank parts 48b
protrude.
[0370] Pressure is applied to the extending part airbags 77L and
77R from the occupant via the bank parts 48b while the valve unit
of the control unit 75 remains opened after the manipulation of the
controller by the occupant. The extending part airbags 77L and 77R
deflate to deform the bank parts 48b of the cushion pad 48 such
that the inflated bank parts 48b get dented. The extending part
airbags 77L and 77R may deflate through the discharge of gas from
the extending part airbags 77L and 77R by the pump.
[0371] Once the operator manipulates the controller to close the
valve unit of the control unit 75, the state of inflation of the
extending part airbags 77L and 77R is kept.
[0372] As shown above, the state of inflation of the extending part
airbags 77L and 77R (extent of deformation of the bank parts 48b of
the cushion pad 48) is adjusted through the manipulation of the
controller by the occupant who opens or closes the valve of the
control unit 75 or starts or stops the pump 87. This enables the
adjustment of the support position of the rear-half of the sides of
the breast-height part of the occupant.
[0373] The seat according to the first modification of the fourth
embodiment can support a wide range of the upper body of the
occupant with the main body part 41a and the extending parts 41b.
This configuration can stabilize the support of the upper body of
the occupant.
[0374] In the first modification, the upper body of the occupant is
supported such that it is laterally surrounded by the extending
part airbags 77L and 77R attached to the left and right extending
parts 41b. This configuration can further stabilize the support of
the upper body of the occupant.
[0375] In the first modification, in particular, the extending part
airbags 77L and 77R have concave contours 77Lb and 77Rb on their
inner faces in the right-left direction. This configuration allows
the upper body of the occupant to fit well between the left and
right extending part airbags 77L and 77R, enabling a more stable
support of the upper body of the occupant.
[0376] In the first modification, the inside ends of the extending
part airbags 77L and 77R in the right-left direction are fixed to
the extending parts 41b with clips 79L and 79R, respectively. Once
gas is fed to the left and right extending part airbags 77L and
77R, the left and right extending part airbags 77L and 77R inflate
such that the airbags 77L and 77R press the bank parts 48b of the
cushion pad 48 inward in the right-left direction. This
configuration allows the upper body of the occupant to fit better
between the left and right extending part airbags 77L and 77R (bank
parts 48b), enabling a more stable support of the upper body of the
occupant.
[0377] In the first modification, the main body airbags 71 and 72
are disposed away from the extending part airbags 77L and 77R such
that they do not come into contact with each other. This
configuration can prevent the interference between the main body
airbags 71 and 72 and the extending part airbags 77L and 77R at the
time of inflation of the air chambers 71a, 72a, 77La and 77Ra.
Second Modification of Fourth Embodiment
[0378] In the fourth embodiment, the extending parts 41b are
partially disposed within the vertical range of the main body
airbag 71 (air chamber 71a), but the present invention should not
be limited to this configuration. For example, with reference to
FIG. 30, the entire extending parts 41b may be disposed within the
vertical range of the main body airbag 71 or 72. This disposition
allows the extending parts 41b to effectively prevent the lateral
movement of the main body airbag 71 or 72. For example, if the
lateral movement of the main body airbags 71 and 72 is adequately
controlled by the cushion pad 48, the extending parts 41b may be
outside of the vertical range of the main body airbags 71 and
72.
Third Modification of Fourth Embodiment
[0379] In the fourth embodiment, the extending parts 41b are formed
only at positions corresponding to the breast height of the
occupant, but the present invention should not be limited to this
configuration. For example, the extending parts 41b may be formed
only at positions corresponding to the waist height of the
occupant. Extending parts other than the extending parts 41b formed
at the breast-height positions of the occupant may be formed at the
waist-height positions of the occupant. If both the breast-height
extending parts and the waist-height extending parts are provided,
they may be formed independently or coupled with each other.
Fourth Modification of Fourth Embodiment
[0380] In the fourth embodiment, the two main body airbags 71 and
72 are disposed on the main body part 41a, but the present
invention should not be limited to this configuration. Either the
main body airbag 71 or 72 may be disposed on the main body part
41a, or one or more main body parts may be provided on the main
body part 41a in addition to the main body airbags 71 and 72. The
air chambers 77La and 78La of the extending part airbags 77L and
77R have the concave contours 77Lb and 77Rb, but the present
invention should not be limited to this configuration. For example,
the air chambers 77La and 78La of the extending part airbags 77L
and 77R may have no concave contour 77Lb and 77Rb as shown in FIG.
33. For example, each of the contours 77Lb and 77Rb may be straight
or curved into a convex shape protruding inward in the right-left
direction.
Modification 5 of Fourth Embodiment
[0381] In the fourth embodiment, the main body airbags 71 and 72 or
the extending part airbags 77L and 77R are the exemplary support
position adjusters, but the present invention should not be limited
to this configuration. The support position adjuster may be an
apparatus primarily equipped with a plate-like member (support
board) and a cable. The plate-like member is resiliently bendable
and deformable and disposed on the pressure receiving member 41
between the pressure receiving member 41 and the cushion pad 48.
The cable can vary the extent of deformation (curvature) of the
support board by pulling the cable or releasing a pulled cable.
Such an adjuster can vary the state of inflation of the cushion pad
48 according to the extent of curvature of the support board,
thereby adjusting the supporting position of the occupant.
Sixth Modification of Fourth Embodiment
[0382] In the fourth embodiment, the coupling portions between the
pressure receiving member 41 and the upper wire rod 43 (claws 41c)
are within the vertical range of the extending parts 41b, but the
present invention should not be limited to this configuration. For
example, with reference to FIG. 30, the claws 41c may be outside of
the vertical range of the extending parts 41b.
[0383] The coupling between the pressure receiving member 41 and
the upper wire rod 43 should not be limited to the use of the claws
41c. For example, pairs of through-holes are disposed in a row in
the right-left direction or in the up-down direction on the
pressure receiving member 41 and the coupling wire rod is fixed
with ties extending through the through-holes. This is also applied
to the coupling between the pressure receiving member 41 and the
lower wire rod 44.
Seventh Modification of Fourth Embodiment
[0384] The main body airbags 71 and 72 and the related members
adopted for the fourth embodiment may be also applied to the seats
1A and 1B according to the second and third embodiments.
Additional Statement on Fourth Embodiment
[0385] As is evident from the above description of the fourth
embodiment and its modifications, the description of the fourth
embodiment and its modifications include various disclosures of
technical ideas in addition to the aspect of the invention shown in
the following notes.
Note 1.
[0386] A vehicle seat including a bottom seat and a backrest,
[0387] wherein the backrest includes a backrest frame constituting
part of the backrest, a cushion pad covering the backrest frame,
and a plate-like pressure receiving member disposed inside the
backrest frame to support load from an occupant,
[0388] wherein the backrest includes a support position adjuster
provided on the pressure receiving member and configured to adjust
a supporting position of the occupant by deforming the cushion pad,
and
[0389] wherein the pressure receiving member includes a main body
part facing a rear surface of the upper body of the occupant and
extending parts extending from right and left edges of the main
body part outward in the right-left direction.
Note 2.
[0390] The vehicle seat according to note 1, wherein the support
position adjuster includes a main body airbag that is attached to a
front surface of the main body part and inflates and deflates to
deform the cushion pad, and
[0391] wherein the extending parts extend from the right and left
edges of the main body part diagonally forward and are disposed at
least partially within a vertical range of the main body
airbag.
Note 3.
[0392] The vehicle seat according to note 2, wherein the support
position adjuster includes an extending part airbag that is mounted
on each extending part and inflates and deflates to deform the
cushion pad.
Note 4.
[0393] The vehicle seat according to note 3, wherein the main body
airbag and each extending part airbag are disposed apart from each
other such that the main body airbag and each extending part airbag
do not come into contact with each other.
Note 5.
[0394] The vehicle seat according to note 3 or 4, wherein each
extending part airbag has a recess on an inner face thereof in the
right-left direction.
Note 6.
[0395] The vehicle seat according to one of notes 1 to 5, wherein
the backrest includes a coupling wire rod put across the backrest
frame and coupling the pressure receiving member to the backrest
frame, and
[0396] wherein a coupling portion between the pressure receiving
member and the coupling wire rod is within a vertical range of the
extending parts.
(a) Advantageous Effects of Present Invention Described in Note
1
[0397] The central main body part and the right and left extending
parts can support a wide range of the upper body of the occupant
via the cushion pad. This configuration can stabilize the support
of the upper body of the occupant.
(b) Advantageous Effects of Present Invention Described in Note
2
[0398] The right and left extending parts can surround at least
part of the main body airbag, thereby preventing the lateral
movement of the main body airbag. This configuration can stabilize
the support of the upper body of the occupant.
(c) Advantageous Effects of Present Invention Described in Note
3
[0399] The support position adjuster may include extending part
airbags attached to the extending parts and inflating and deflating
to deform the cushion pad.
(d) Advantageous Effects of Present Invention Described in Note
4
[0400] The upper body of the occupant is supported by the extending
part airbags attached to the right and left extending parts such
that the upper body is laterally surrounded by the extending part
airbags. This configuration can further stabilize the support of
the upper body of the occupant.
(e) Advantageous Effects of Present Invention Described in Note
5
[0401] The present invention described in Note 5 allows the upper
body of an occupant to fit well between the right and left
extending part airbags. This configuration can further stabilize
the support of the upper body of the occupant.
(f) Advantageous Effects of Present Invention Described in Note
6
[0402] The pressure receiving member is coupled to the backrest
frame via the coupling wire rod at the height of the extending
parts. This enables the extending parts and the main body part at
the height of the extending parts to receive the occupant load
efficiently. This configuration can further stabilize the support
of the upper body of the occupant.
Fifth Embodiment
[0403] FIG. 35 is a perspective view of a seat 1D according to the
fifth embodiment of the present invention. FIG. 36 is a rear view
of the backrest frame 40 of the seat 1D according to the fifth
embodiment of the present invention. FIG. 37 is a perspective view
of the rear surface of the pressure receiving member 41 of the seat
1D according to the fifth embodiment of the present invention. The
same parts between the seat 1D according to the fifth embodiment
and the seat 1 according to the first embodiment are given the same
reference numerals. If the same parts are provided in the same
manner, the explanation thereof will be omitted if possible. The
following description focuses on differences between the seat 1D
according to the fifth embodiment and the seat 1 according to the
first embodiment.
[0404] Differences between the seat 1D according to the fifth
embodiment and the seat 1 according to the first embodiment lie in
the backrest 4. More specifically, as shown in FIGS. 35 to 37, the
seat 1D according to the fifth embodiment is provided with a
vibration generator 80 for vibrating an occupant seated on the seat
1D in the backrest 4. In contrast, the seat 1 according to the
first embodiment is not provided with the vibration generator 80.
The backrest 4 of the seat 1D according to the fifth embodiment is
provided in the same manner as the backrest 4 of the seat 1
according to the first embodiment, except for the vibration
generator 80, which is provided on the pressure receiving member
41.
[0405] The seat 1D according to the fifth embodiment includes slide
rails, a bottom seat 3, a recliner mechanism 5, and a headrest 6,
which are provided in the same manner as the slide rails 2, the
bottom seat 3, the recliner mechanism 5, and the headrest 6 of the
seat 1 according to the first embodiment (See FIG. 35).
[0406] The vibration generator 80 and relevant items will now be
described.
[0407] The vibration generator 80 generates continuous or
intermittent vibrations to provide an occupant with massage effect
and/or awakening effect. The vibration generator 80 primarily
includes a motor 81, an eccentric weight 82, and a mounting bracket
83. The motor 81 is driven to rotate the eccentric weight 82 and
generate vibrations.
[0408] The eccentric weight 82 is a substantially fan-shaped
weight. The eccentric weight 82 is fixed to a rotary shaft 81a of
the motor 81 at a position deviating from the center of gravity of
the eccentric weight 82, more specifically, near the pivot (center
angle) of the fan. The eccentric weight 82 primarily includes
multiple plate-like weight units 82a. The weight units 82a
according to this embodiment are stackable in the axial direction
(right-left direction) of the motor 81. The weight units 82a are
fixable by screws 84 and separable from each other. This
configuration can readily adjust the mass of the eccentric weight
82 by varying the number of weight units 82a. This can also readily
vary the magnitude of vibration generated by the vibration
generator 80 in accordance with the size of the seat equipped with
the vibration generator 80.
[0409] The mounting bracket 83 is an L-shaped member made of metal
or resin. The mounting bracket 83 includes a fixing portion 83a and
a mounting portion 83b. The fixing portion 83a and the mounting
portion 83b are each plate-like. The fixing portion 83a is
perpendicular to the mounting portion 83b to form an L-shaped
mounting bracket 83. The rotary shaft 81a of the motor 81 extends
through the fixing portion 83a. The motor 81, in particular, a main
body part 81b is fixed to the fixing portion 83a by a screw. The
fixing portion 83a is disposed between the main body part 81b of
the motor 81 and the eccentric weight 82. The mounting portion 83b
extends from the corner between the fixing portion 83a and the
mounting portion 83b on the side of the main body part 81b
generally in parallel with the axial direction of the motor 81. A
through-hole 83c is provided at each end of the longitudinal
direction of the mounting portion 83b (only one through-hole is
shown). In orthogonal view to the mounting portion 83b, the main
body part 81b of the motor 81 is disposed between the through-holes
83c.
[0410] The vibration generator 80 is fixed to the pressure
receiving member 41 by bolt and nut coupling. The vibration
generator 80 is fixed to the pressure receiving member 41 below the
lower wire rod 44 of the pressure receiving member 41, more
specifically, in the lower portion of a rear surface 41r of the
main body part 41a. This indicates that the vibration generator 80
is disposed not at the front edges 41b1 of the extending parts
41b.
[0411] A pair of bolts 85a protrudes from the pressure receiving
member 41, in particular, from the rear surface of the main body
part 81b. More specifically, the pair of the bolts 85a is provided
on the pressure receiving member 41 by insert molding or by being
inserted into the through-holes on the pressure receiving member 41
from the front. The bolts 85a are inserted into the through-holes
83c of the mounting bracket 83. The mounting portion 83b of the
mounting bracket 83 is disposed between each nut 85b and the
pressure receiving member 41. The nuts 85b are fastened to the
bolts 85a. The mounting bracket 83 is thereby fixed to the pressure
receiving member 41. The fixing portion 63b is perpendicular to the
rear surface 41b of the pressure receiving member 41, while the
mounting bracket 83 is fixed to the pressure receiving member 41.
The mounting portion 83b extends from the front end of the fixing
portion 83a over the rear surface 41b of the pressure receiving
member 41. The mounting portion 83b has a greater vertical
length.
[0412] The vibration generator 80 is activated to generate
vibrations. When the motor 81 rotates the eccentric weight 82,
vibrations are generated since the rotary shaft 81a deviates from
the center of gravity of the eccentric weight 82. When the
vibration generator 80 starts to vibrate, the pressure receiving
member 41, which is suspended from the backrest frame 40 by wire
rods 43 and 44, also vibrates. The vibrations of the pressure
receiving member 41 are transmitted from the pressure receiving
member 41 to an occupant leaning back the cushion pad 48 via the
cushion pad 48 to provide the occupant with massage effect,
awakening effect or both.
[0413] At a rear-end collision by another vehicle, the upper body
of the occupant is pressed against the cushion pad 48 to
significantly deform the near-center portion of the cushion pad 48.
If the impulsive force is so large that a backward load exceeding a
predetermined value is applied to the pressure receiving member 41
by the upper body of the occupant via the cushion pad 48, the
pressure receiving member 41 moves backward relative to the left
and right side frame segments 40b and the upper body of the
occupant deeply sinks into the backrest 4. As a result, the head of
the occupant rapidly approaches the headrest 6 and is supported
thereby, thus protecting the head and the neck region of the
occupant from the impact of the collision of the rear surface of
the vehicle.
[0414] Advantageous effects of the seat with such a configuration
will now be described.
[0415] The pressure receiving member 41 of the seat includes the
main body part 41a and the right and left extending parts 41b.
Thus, the central main body part 41a and the right and left
extending parts 41b can support a wide range of the upper body of
the occupant. This configuration can stabilize the support of the
upper body of the occupant. The vibration generator 80 is disposed
at a position avoiding the positions of the front edges (front ends
or the ends of the extending parts) 41b1, which most largely move
due to the deformation of the extending parts 41b. This disposition
can prevent the vibration generator 80 from reducing the
deformation of the extending parts 41b. The disposition of the
vibration generator 80 at a position avoiding the positions of the
front edges 41b1 of the extending parts 41b, which most largely
displace, can prevent the attenuation of the vibrations generated
by the vibration generator 80, thus efficiently transmitting
vibrations to the occupant.
[0416] In this embodiment, the vibration generator 80 is mounted on
the main body part 41a and thus disposed away from the extending
parts 41b. This disposition can prevent the vibration generator 80
from reducing the deformation of the extending parts 41b. The
attachment of the vibration generator 80 to the main body part 41a,
which is less likely to deform than the extending parts 41b, can
effectively prevent the attenuation of the vibrations generated by
the vibration generator 80, thus efficiently transmitting
vibrations to the occupant.
[0417] In this embodiment, the vibration generator 80 is mounted in
the lower portion of the main body part 41a, which is close to the
contact portion between the backrest 4 and the upper body of the
occupant during a normal seating. This disposition can transmit the
vibrations generated by the vibration generator 80 more efficiently
to the occupant. The vibration generator 80 mounted in the lower
portion of the main body part 41a can significantly vibrate the
pressure receiving member 41 with the vibrations generated by the
vibration generator 80 and thus can transmit large vibrations to
the occupant. This enhances massage effect, awakening effect or
both.
[0418] In this embodiment, the vibration generator 80 is mounted on
the rear surface 41r of the main body part 41a. This mounted
structure prevents the occupant from feeling a sense of discomfort
caused by the vibration generator 80.
[0419] The vibration generator 80 mounted on the rear surface of
the main body part 41a as in this embodiment makes the vibration
generator 80 less offending in the backrest 4 than the mounting of
the vibration generator on the front surface of the main body part
41a. This configuration enables mount of a relatively large
vibration generator capable of generating large vibrations, if
necessary, for example, for a large seat.
[0420] The fifth embodiment of the present invention has been
described above. The embodiments applicable to the present
invention should not be limited to those described above and may be
modified as appropriate within the scope of the present invention.
The following description focuses on several modifications of the
fifth embodiment. These modifications are the same as the fifth
embodiment except for some changes. The following modifications may
be combined according to demand.
First Modification of Fifth Embodiment
[0421] In the above description, the vibration generator 80 is
disposed on the main body part 41a, as shown in FIG. 36. In
contrast, in the first modification, two vibration generators 80
are disposed, one on the right extending part 41b and the other on
the left extending part 41b, as shown in FIG. 38. FIG. 38 is a rear
view of a frame 40 of a backrest 4 according to the first
modification of the fifth embodiment.
[0422] The pressure receiving member 41 primarily includes a main
body part 41a and right and left extending parts 41b. Each
extending part 41b resiliently bends and deforms in the front-back
direction along the connecting line between the extending part 41b
and the main body part 41a. In this embodiment, a bead 41g is
formed on the pressure receiving member 41. The bead 41g is concave
in front view and convex in rear view. The bead 41g includes
multiple vertical beads 41g1, a lower bead 41g2, and multiple upper
beads 41g3. The multiple vertical beads 41g1 extend vertically. The
lower bead 41g2 extends in the right-left direction to couple the
lower portions of the vertical beads 41g1. The multiple upper beads
41g3 extend from the upper portions of the rightmost and leftmost
vertical beads 41g1 diagonally upward to the outside in the
right-left direction.
[0423] The vertical beads 41g1 and the lower bead 41g2 are formed
on the main body part 41a. In contrast, the upper beads 41g3
continuously extend from the right and left upper portions of the
main body part 41a to the front edges of the extending parts 41b.
Three upper beads 41g3 are formed on the right and left sides of
the pressure receiving member 41 and disposed vertically side by
side. The upper beads 41g3 are exemplary reinforcing members. The
portion of the extending parts 41b provided with the upper beads
41g3 has higher rigidity than other portion of the extending part
41b without the upper beads 41g3.
[0424] FIG. 39 is a perspective view of the rear surface of the
left extending part 41b of the pressure receiving member 41. As
shown in FIG. 39, the left vibration generator 80 primarily
includes a motor 81, an eccentric weight 82, and a mounting bracket
86. The mounting bracket 86 is a T-shaped member. The mounting
bracket 86 includes a fixing portion 86a and a mounting portion
86b. The mounting portion 86b has a strip shape. The fixing portion
86a is erected at the center of the mounting portion 86b. The motor
81 has a rotary shaft passing through the fixing portion 86a and
has a main body part 81b fixed to the fixing portion 86a. The
eccentric weight 82 is fixed to the rotary shaft of the motor 81 on
the opposite side of the main body part 81b with respect to the
fixing portion 86a. The center of gravity of the eccentric weight
82 deviates from the rotary shaft of the motor 81. A through-hole
86c is provided at each end of the longitudinal direction of the
mounting portion 86b.
[0425] The vibration generator 80 is fixed to the pressure
receiving member 41 at the upper beads 41g3. Each vibration
generator 80 is mounted at the center (with respect to the
right-left direction) of the rear surface 41b5 of the corresponding
extending part 41b of the pressure receiving member 41. This
indicates that each vibration generator 80 is disposed away from
the front edge 41b1 of the extending part 41b, similarly to the
first embodiment.
[0426] The vibration generators 80 are fixed to the extending parts
41b by bolt and nut coupling. Two bolts 87a are provided on the top
and bottom upper beads 41g3 on each extending part 41b. The bolts
87a extend through the through-holes 86c in the mounting portion
86b. The mounting portion 86b is disposed between each nut 87b and
each extending part 41b. Each nut 87b is fastened to the
corresponding bolt 87a. The vibration generator 80 is thereby fixed
to the pressure receiving member 41 at the upper beads 41g3. The
fixing portion 86a is erected on the rear surface 41b5 of the
extending part 41b, while the mounting bracket 86 is fixed to the
extending part 41b. The mounting portion 86b extends from the front
end of the fixing portion 83a over the rear surface 41b5 of each
extending part 41b in the axial direction (vertical direction) of
the motor 81. The mounting portion 86b has a greater vertical
length.
[0427] The right vibration generator 80 has the same configuration
as that of the left vibration generator 80. The right vibration
generator 80 is fixed to the right extending part 41b, similarly to
the left vibration generator 80, which is fixed to the left
extending part 41b.
[0428] Similarly to the first modification of the fifth embodiment,
the main body part 41a and the right and left extending parts 41b
of the first modification can support a wide range of the upper
body of the occupant. This configuration can stabilize the support
of the upper body of the occupant. The vibration generators 80,
disposed at position avoiding the positions of the front edges 41b1
of the extending parts 41b, can maintain a proper deformation of
the extending parts 41b and efficiently transmit the vibrations to
the occupant.
[0429] In the first modification, each vibration generator 80,
mounted on the center (with respect to the right-left direction) of
the extending part 41b, can maintain a proper deformation of the
extending parts 41b. Each vibration generator 80 mounted at the
center (with respect to the right-left direction) of the extending
part 41b can maintain a proper deformation of the extending parts
41b more effectively than each vibration generator 80 mounted near
the connecting portion between the extending part 41b and the main
body part 41a, at which the extending part 41b bends.
[0430] In the first modification, the pressure receiving member 41,
having the beads 41g, have enhanced rigidity, thus further
stabilizing the support of the upper body of the occupant. The
vibration generators 80, mounted on the extending parts 41b having
an increased rigidity due to the upper beads 41g3, stabilize the
mount of the vibration generators 80 on the extending parts 41b.
This configuration can enhance the rigidity of the mounted
vibration generators 80 and thus can transmit vibrations to the
occupant efficiently.
[0431] In the first modification, the vibration generators 80 are
mounted on the right and left extending parts 41b. Thus, the
extending parts 41b can stabilize the support of the upper body of
the occupant while transmitting the vibrations generated by the
vibration generators 80 to the occupant from the right and left of
the rear surface of the upper body. This configuration can enhance
massage effect and/or awakening effect.
[0432] In the first modification, the vibration generators 80,
mounted on the rear surfaces 41b5 of the extending parts 41b, can
prevent the occupant from feeling a sense of discomfort caused by
the vibration generators 80.
Second Modification of Fifth Embodiment
[0433] In the fifth embodiment, the vibration generator 80 is
mounted in the lower portion of the main body part 41a, but the
present invention should not be limited to this configuration. For
example, the vibration generator 80 may be mounted in the upper
portion or at the vertical center of the main body part 41a of the
pressure receiving member 41. Since the lower portion of the main
body part 41a is a position at which the upper body of the occupant
comes into contact with the backrest 4 during normal sitting of an
occupant, the vibrations generated by the vibration generator 80 is
efficiently transmitted to the occupant. Thus, the vibration
generator 80 is preferably mounted below the vertical center of the
main body part 41a.
Third Modification of Fifth Embodiment
[0434] In the fifth embodiment, the vibration generator 80 is
mounted only on the main body part 41a. In the first modification,
the vibration generators 80 are mounted only on the extending parts
41b, but the present invention should not be limited to this
configuration. One or more vibration generators 80 may be mounted
on the main body part 41a, one or more vibration generators 80 may
be mounted on the left extending part 41b, and one or more
vibration generators 80 may be mounted on the right extending part
41b.
Fourth Modification of Fifth Embodiment
[0435] In the first modification, two vibration generators 80 are
mounted, one on the right extending part 41b and the other on the
left extending part 41b, but the present invention should not be
limited to this configuration. One or more vibration generators 80
may be mounted on either right or left extending part 41b and no
vibration generator may be mounted on the other extending part
41b.
Fifth Modification of Fifth Embodiment
[0436] In the first modification, vibration generators 80 are each
mounted on the extending part 41b at the upper beads 41g3, but the
present invention should not be limited to this configuration. For
example, even if the vibration generator 80 is mounted on the main
body part 41a, the vibration generator 80 may be fixed to the main
body part 41a at a bead formed on the main body part 41a.
Sixth Modification of Fifth Embodiment
[0437] In the first and fifth modifications, exemplary reinforcing
members for reinforcing the pressure receiving member 41 are beads
(for example, the upper beads 41g3 for the extending part 41b), but
the present invention should not be limited to this configuration.
For example, a part of the pressure receiving member 41 may have a
greater thickness for higher rigidity than the other part to use
the thicker portion as a reinforced portion.
Seventh Modification of Fifth Embodiment
[0438] In the fifth embodiment, the upper wire rod 43 and the lower
wire rod 44 are put across the backrest frame 40 as coupling wire
rods in the right-left direction, but the present invention should
not be limited to this configuration. For example, the coupling
wire rods may be put vertically or diagonally across the backrest
frame 40.
Eighth Modification of Fifth Embodiment
[0439] The configuration of the vibration generator 80 shown in the
fifth embodiment and the first modification thereof is an exemplary
one, but the present invention should not be limited to this
configuration. For example, the eccentric weight 82 in the fifth
embodiment and the first modification thereof is composed of
several pieces so as to adjust the number of weight units 82a, but
the present invention should not be limited to this configuration.
The eccentric weight 82 may be composed of a single piece. A
bracket for mounting the vibration generator 80 on the pressure
receiving member 41 is not limited to the mounting brackets 83 and
86 shown in the fifth embodiment and the first modification
thereof, but may have any configuration suitable for a mounting
portion on the pressure receiving member 41.
Ninth Modification of Fifth Embodiment
[0440] In the fifth embodiment, the extending parts 41b are formed
only at positions corresponding to the breast height of the
occupant, but the present invention should not be limited to this
configuration. For example, the extending parts 41b may be formed
only at positions corresponding to the waist height of the
occupant. Extending parts other than the extending parts 41b formed
at the breast-height positions of the occupant may be formed at the
waist-height positions of the occupant. If both the breast-height
extending parts and the waist-height extending parts are provided,
they may be formed independently or coupled with each other.
Tenth Modification of Fifth Embodiment
[0441] The vibration generator 80 of the fifth embodiment may be
applied to the seats LA, 1B, and 1C according to the second, third
and fourth embodiments, respectively. This is also applied to the
vibration generators 80 of the first modification of the fifth
embodiment.
Additional Statement on Fifth Embodiment
[0442] As is evident from the above description of the fifth
embodiment and its modifications, the description of the fifth
embodiment and its modifications include various disclosures of
technical ideas in addition to the aspect of the invention shown in
the following notes.
Note 1.
[0443] A vehicle seat having a bottom seat and a backrest, the
vehicle seat including:
[0444] a backrest frame constituting part of the backrest;
[0445] a coupling wire rod put across the backrest frame;
[0446] a plate-like pressure receiving member coupled to the
backrest frame via the coupling wire rod and receiving load from an
occupant; and
[0447] a vibration generator mounted on the pressure receiving
member and providing the occupant with vibrations,
[0448] wherein the pressure receiving member includes a main body
part facing a rear surface of the upper body of the occupant and
extending parts extending from right and left edges of the main
body part outward in the right-left direction and being resiliently
deformable in the front-back direction, and
[0449] wherein the vibration generator is disposed at a position
avoiding positions of the front edges of the extending parts.
Note 2.
[0450] The vehicle seat according to note 1, wherein the vibration
generator is mounted on the main body part.
Note 3.
[0451] The vehicle seat according to note 2, wherein the vibration
generator is mounted on a rear surface of the main body part.
Note 4.
[0452] The vehicle seat according to note 2 or 3, wherein the
vibration generator is disposed below a vertical center of the main
body part.
Note 5.
[0453] The vehicle seat according to note 4, wherein the vibration
generator is mounted on a lower end portion of the main body
part.
Note 6.
[0454] The vehicle seat according to note 1, wherein the vibration
generator is mounted on an extending part of the extending
parts.
Note 7.
[0455] The vehicle seat according to note 6, wherein the extending
part has a reinforced portion having greater rigidity than the
other portion of the extending part, and
[0456] wherein the vibration generator is fixed at the reinforced
portion.
Note 8.
[0457] The vehicle seat according to note 6 or 7, wherein the
vibration generator is mounted on a rear surface of the extending
part.
(a) Advantageous Effects of Present Invention Described in Note
1
[0458] The central main body part and the right and left extending
parts can support a wide range of the upper body of the occupant.
This configuration can stabilize the support of the upper body of
the occupant. The vibration generator mounted at a position
avoiding the positions of the front edges of the extending parts,
which most largely move due to the deformation of the extending
parts, can prevent the vibration generator from reducing the
deformation of the extending parts and the attenuation of the
vibrations generated by the vibration generator, thereby
efficiently transmitting vibrations to the occupant.
(b) Advantageous Effects of Present Invention Described in Note
2
[0459] The present invention described in Note 2 can maintain
proper deformation of the extending parts and efficiently transmit
vibrations generated by the vibration generator to the
occupant.
(c) Advantageous Effects of Present Invention Described in Note
3
[0460] The present invention described in Note 3 can prevent the
occupant from feeling a sense of discomfort caused by the vibration
generator. This allows a relatively large vibration generator
capable of generating large vibrations to be mounted.
(d) Advantageous Effects of Present Invention Described in Note
4
[0461] The vibration generator mounted below the vertical center of
the main body part, which is a main contact portion between the
upper body of the occupant and the backrest during a normal
seating, can transmit the vibrations generated by the vibration
generator more efficiently to the occupant.
(e) Advantageous Effects of Present Invention Described in Note
5
[0462] The vibrations generated by the vibration generator can
significantly vibrate the pressure receiving member and thus can
transmit greater vibrations to the occupant. This can enhance
massage effect and/or awakening effect.
(f) Advantageous Effects of Present Invention Described in Note
6
[0463] The present invention described in Note 6 can stabilize the
support of the upper body of the occupant while transmitting the
vibrations generated by the vibration generator to the occupant
from the right and left of the rear surface of the upper body. This
can enhance massage effect and/or awakening effect.
(g) Advantageous Effects of Present Invention Described in Note
7
[0464] The extending part having the reinforced portion can further
stabilize the support the upper body of the occupant and the mount
of the vibration generator on the extending part. This
configuration enhances the mounting rigidity of the vibration
generator and can transmit the vibrations generated by the
vibration generator to the occupant more efficiently.
(h) Advantageous Effects of Present Invention Described in Note
8
[0465] The vibration generator can prevent the occupant from
feeling a sense of discomfort.
Sixth Embodiment
[0466] FIG. 40 is a perspective view of a seat 1E according to a
sixth embodiment of the present invention. FIG. 41 is a perspective
view of a seat frame of the seat 1E. FIG. 42 is a front view of the
backrest 4 of the seat 1E. FIG. 42 illustrates a cushion pad 48 of
the backrest 4 with a two-dot chain lines to show the inside of the
backrest 4. FIG. 43 is a cross sectional view taken along line
XXXXIV-XXXXIV in FIG. 42, viewed in the direction of arrows. The
same parts between the seat 1E according to the sixth embodiment
and the seat 1 according to the first embodiment are given the same
reference numerals. If the same parts are provided in the same
manner, the explanation thereof will be omitted if possible. The
following description focuses on differences between the seat 1E
according to the sixth embodiment and the seat 1 according to the
first embodiment.
[0467] Differences between the seat 1E according to the sixth
embodiment and the seat 1 according to the first embodiment lie in
the backrest 4. More specifically, the backrest 4 of the seat 1E
according to the sixth embodiment includes a pair of the right and
left deformation controlling means for controlling the extent of
deformation of the extending parts 41b. As shown in FIGS. 40 to 43,
the deformation controlling means includes supporting wire rods
(side support members) 100. The extending part 41b provided in the
backrest 4 according to the sixth embodiment have a greater
horizontal length than the extending part 41b provided in the
backrest 4 according to the first embodiment. A hook-like engaging
portion 41h is formed at each front edge of the extending part 41b
of the seat 1E according to the sixth embodiment. The hook-like
engaging portion 41h bends diagonally backward to the outside in
the right-left direction. The backrest 4 of the seat 1E according
to the sixth embodiment is provided in the same manner as that of
the seat 1 according to the first embodiment except for the
components described above.
[0468] The seat 1E according to the sixth embodiment includes slide
rails, a bottom seat 3, a recliner mechanism 5, and a headrest 6.
These are provided in the same manner as the slide rails 2, the
bottom seat 3, the recliner mechanism 5, and the headrest 6 of the
seat 1 according to the first embodiment.
[0469] The pair of the right and left supporting wire rods 100, the
extending parts 41b and the engaging portions 41h will now be
described.
[0470] The left side frame segment 40b includes the left supporting
wire rod 100. The right side frame 40b includes the right
supporting wire rod 100. The supporting wire rods (side support
members) 100 are provided inside the backrest 4. The supporting
wire rods 100 are formed by bending a metal rod into a
substantially U shape. The supporting wire rods 100 are contact
members (stoppers).
[0471] The left supporting wire rod 100 is attached to the left
side frame segment 40b by welding such that it connects the top end
of the main body part 40b2 of the left side frame segment and a
protrusion 40b3 thereof. The right supporting wire rod 100 is also
attached to the right side frame 40b in a similar manner.
[0472] As shown in FIGS. 42 and 43, the extending parts 41b
primarily support the rear-half of the sides of the breast-height
part of the occupant's upper body via the bank parts 48b. The
extending parts 41b are integrated with the main body part 41a. The
extending parts 41b extend from the right and left upper edges of
the main body part 41a. More specifically, the extending parts 41b
extend from the portions of the main body part 41a at the breast
height of the occupant diagonally forward to the outward in the
right-left direction to the front of the supporting wire rods 100
of the side frame segments 40b and the side frame segments 40b.
Each extending part 41b is apart frontward from the supporting wire
rod 100 with a certain gap between the extending part 41b and the
supporting wire rod 100. The extending parts 41b extending to the
front of the side frame segments 40b prevent the overlap of the
front edges 41b1 of the extending parts 41b with the upper wire rod
43 in front view, as shown in FIG. 42.
[0473] The advantageous effects of the seat 1E with such a
configuration will now be described.
[0474] When an occupant leans against the backrest 4 during a
normal seating, load is applied from the upper body of the occupant
to the pressure receiving member 41 via the cushion pad 48. The
pressure receiving member 41, which includes the main body part 41a
and the right and left extending parts 41b, can support a wide
range of the upper body of the occupant with the central main body
part 41a and the right and left extending parts 41b. This
configuration can stabilize the support of the upper body of the
occupant.
[0475] When the occupant leans against the backrest 4, the bank
parts 48b of the cushion pad 48 deform and the extending parts 41b
also resiliently bend backward accordingly. As the bank parts 48b
have a greater extent of deformation, the extending parts 41b
further bend backward. As shown with the chain lines in FIG. 43, at
a predetermined amount of bending of the extending parts 41b, the
front edges of the extending parts 41b come into contact with the
supporting wire rods 100. This contact precludes further bending of
the extending parts 41b. The supporting wire rods 100, which can
control the extent of deformation of the extending parts 41b, can
prevent excess deformation of the extending parts 41b. This
configuration can also stabilize the support of the upper body of
the occupant.
[0476] In this embodiment, when the front edges of the extending
parts 41b come into contact with the supporting wire rods 100, the
engaging portions 41h are engaged with the supporting wire rods
100. An embodiment having the engaging portions 41h as in this
embodiment can control the positions of the front edges of the
extending parts 41b more strictly than an embodiment without the
engaging portions 41h. This configuration can prevent excess
deformation of the extending parts 41b and stabilize the support of
the upper body of the occupant.
[0477] In this embodiment, the contact between the front edges of
the extending parts 41b and the supporting wire rods 100 controls
the extent of deformation of the extending parts 41b. This, in
turn, indicates that the deformation of the extending parts 41b is
allowable until the front edges of the extending parts 41b comes
into contact with the supporting wire rods 100. This configuration
ensures a necessary extent of deformation for the extending parts
41b.
[0478] In this embodiment, the claws 41c at which the pressure
receiving member 41 is coupled to the upper wire rod 43 are within
the vertical range of the extending parts 41b. This disposition
allows the pressure receiving member 41 to be coupled to the
backrest frame 40 at the height of the extending parts 41b via the
upper wire rod 43. This coupling stabilizes the posture of the
pressure receiving member 41 (the extending parts 41b) and allows
the supporting wire rods 100 to prevent excess deformation of the
extending parts 41b. This configuration can further stabilize the
support of the upper body of the occupant.
[0479] This embodiment includes the supporting wire rods 100, which
are attached to the side frame segments 40b as contact members. If
no supporting wire rod 100 is provided on the side frame segments
40b, the portions that come into contact with the front edges of
the extending parts 41b should be provided on the side frame
segments 40b themselves to use the side frame segment 40b as
contact members. In contrast, the supporting wire rods 100 provided
on the side frame segments 40b as in this embodiment eliminate the
necessity for forming contact portions on the side frame segments
40b. This helps prevent the increase in size of the frame segments
40b. The elimination of the necessity for forming contact portions
on the side frame segments 40b indicates the elimination of the
necessity for producing the side frame segments 40b dedicated to
the seat 1E according to this embodiment. This can enhance the
versatility of the side frame segments 40b since the side frame
segments 40b can be used for seats other than the seat 1E.
[0480] The front edges 41b1 of the extending parts 41b do not
overlap with the upper wire rod 43 in front view. This
configuration can prevent the interference between the front edges
41b1 and the upper wire rod 43 even if the deformation of the
extending parts 41b causes the front edges 41b1 to move in the
front-back direction.
[0481] At a rear-end collision by another vehicle, the upper body
of the occupant is pressed against the cushion pad 48 to
significantly deform the near-center portion of the cushion pad 48.
If the impulsive force is so large that a backward load exceeding a
predetermined value is applied to the pressure receiving member 41
by the upper body of the occupant via the cushion pad 48, the
pressure receiving member 41 moves backward relative to the left
and right side frame segments 40b. In this case, the front edges of
the extending parts 41b come into contact with the supporting wire
rods 100 to cause the engaging portions 41h to catch the supporting
wire rods 100. In case of a large backward load applied, the
engaging portions 41h can deform and release the supporting wire
rods 100, thus enabling a backward movement of the pressure
receiving member 41.
[0482] The backward movement of the pressure receiving member 41
causes the upper body of the occupant to deeply sink into the
backrest 4. As a result, the head of the occupant rapidly
approaches the headrest 6 and is supported thereby, thus protecting
the head and the neck region of the occupant from the impact of the
collision of the rear surface of the vehicle.
[0483] The sixth embodiment of the present invention has been
described. The embodiments applicable to the present invention
should not be limited to those described above and may be modified
as appropriate within the scope of the present invention. The
following description focuses on several modifications of the sixth
embodiment. These modifications are the same as the sixth
embodiment except for some changes. The following modifications may
be combined according to demand.
First Modification of Sixth Embodiment
[0484] FIG. 44 is a cross-sectional view of a backrest 4 according
to a first modification of the sixth embodiment. Since the backrest
4 is formed substantially symmetrically, FIG. 44 is an enlarged
view of only the right side frame segment 40b and its
surroundings.
[0485] As shown in FIG. 44, the pressure receiving member 41
primarily includes a main body part 41a and right and left
extending parts 41b. In the first modification, each extending part
41b can resiliently bend and deform in the front-back direction
along the connecting line between the extending part 41b and the
main body part 41a. Each extending part 41b has a front edge bent
frontward. The bent front edge has a contact piece 41j.
[0486] The backrest 4 includes a deformation controlling means for
controlling the extent of deformation of the extending parts 41b.
As shown in FIG. 44, the deformation controlling means includes
right and left pan frames 101. The right and left pan frames are
plates facing each other in the right-left direction. Each pan
frame 101 bridges the supporting wire rods 100 of each side frame
segment 40b in the front-back direction and fixed to the supporting
wire rods 100 by welding. The pan frames 101 are disposed outside
the pressure receiving member 41 in the right-left direction. As
shown with the chain lines in FIG. 44, each pan frame 101 is
disposed such that the front edge of the extending part 41b
(contact piece 41j) comes into contact with an inner surface 101a
of the pan frame 101 at a predetermined extent of deformation of
the extending part 41b. Each pan frame 101 is disposed such that
the front edge of the extending part 41b slides on the inner
surface 101a while in contact therewith until the front edge of the
extending part 41b (contact piece 41j) can no longer move on the
inner surface 101a. The pan frames 101 are contact members
(stoppers).
[0487] Similarly to the sixth embodiment, the main body part 41a
and the right and left extending parts 41b can support a wide range
of the upper body of the occupant. This configuration can stabilize
the support of the upper body of the occupant. The contact between
the front edge of each extending part 41b bending backward and the
inner surface 101a of the pan frame 101 can prevent excess
deformation of the extending part 41b. This can also stabilize the
support of the upper body of the occupant.
[0488] In the first modification of the sixth embodiment, the
plate-like pan frames 101 are used as contact members. This
indicates the front edges of the extending parts 41b come into
contact with surfaces (the inner surfaces 101a). Such a contact
through surfaces can maintain the contact between the front edges
and the pan frames 101 and ensure the prevention of excess
deformation of the extending parts 41b. This configuration can
further stabilize the support of the upper body of the
occupant.
[0489] In the first modification of the sixth embodiment, the
sliding contact between the front edges of the extending parts 41b
and the inner surfaces 101a allows deformation of the extending
parts 41b until the front edges of the extending parts 41b can no
longer move on the inner surfaces 101a. This ensures a necessary
extent of deformation for the extending parts 41b.
[0490] FIG. 45 illustrates a modification of each pan frame 101.
The pan frame 101 may have a controlling portion 101b. The
controlling portion 101b is formed into a step. The step is formed
by creating a recess on the inner surface 101a of the pan frame
101. The inner surface, facing the front, of the recess is the
controlling portion 101b. At the time of a backward bend of the
extending parts 41b, the front edge of each extending part 41b
(contact piece 41j) that slides backward on the inner surface 101a
of the pan frame 101 comes into contact with the controlling
portion 101b. The contact between the front edge of each extending
part 41b (contact piece 41j) and the controlling portion 101b can
prevent excess deformation of the extending part 41b, thus further
stabilizing the support of the upper body of the occupant.
Second Modification of Sixth Embodiment
[0491] FIG. 46 is a cross sectional view of a backrest 4 according
to a second modification of the sixth embodiment. Since the
backrest 4 is formed substantially symmetrically, FIG. 46 is an
enlarged view of only the right side frame segment 40b and its
surroundings.
[0492] The backrest 4 includes a deformation controlling means for
controlling the extent of deformation of the extending parts 41b.
As shown in FIG. 46, the deformation controlling means includes
right and left pan frames 101. The right and left pan frames 101
are plates facing each other in the right-left direction. Similarly
to the first modification, each pan frame 101 bridges the
supporting wire rods 100 of each side frame segment 40b in the
front-back direction and fixed to the supporting wire rods 100. A
through-hole 101c is formed on each pan frame 101 at the front end
thereof. The through-hole 101c has the shape of a long slit in the
vertical direction.
[0493] The pressure receiving member 41 primarily includes a main
body part 41a and right and left extending parts 41b. Each
extending part 41b is curved into an arc in the horizontal cross
sectional view. Each extending part 41b in the first modification
is curved with a curvature greater than that of the extending part
41b in the sixth embodiment or its first modification.
[0494] Each extending part 41b has a front edge bent frontward. The
bent front edge has a locking piece 41k. The front edge of the
extending part 41b passes through the through-hole 101c in the pan
frame 101 to control the anteroposterior positions of the front
edge and a base edge 41b6 of the extending part 41b. This
configuration allows a central portion 41b7 of the extending part
41b to resiliently bend substantially in the front-back direction,
as shown with the chain lines in FIG. 46.
[0495] The controlled anteroposterior positions of the front edges
of the extending parts 41b control the extent of deformation. The
deformation controlling means is achieved by the front edge of each
extending part 41b inserted into the through-hole 101c formed in
the pan frame 101.
[0496] The second modification having such a configuration can also
support a wide range of the upper body of the occupant with the
main body part 41a and the extending parts 41b and thus stabilize
the support of the upper body of the occupant. The front edge of
each extending part 41b inserted into the through-hole 101c in the
pan frame 101 can prevent excess deformation of the support. This
configuration stabilizes the support of the upper body of the
occupant.
[0497] In the second modification, the front edge of each extending
part 41b inserted into the through-hole 101c prevents the
front-back movement of the front edge of the extending part 41b.
This configuration can further prevent excess deformation of the
extending part 41b and stabilizes the support of the upper body of
the occupant.
Third Modification of Sixth Embodiment
[0498] FIG. 47 is a perspective view of a backrest frame 40 of a
backrest 4 according to a third modification of the sixth
embodiment. FIG. 48 is a front view of the backrest frame 40 of the
backrest 4 according to the third modification of the sixth
embodiment. FIG. 49 is a cross sectional view of the backrest 4
according to the third modification of the sixth embodiment. Since
the backrest 4 is formed substantially symmetrically, FIG. 49 is an
enlarged view of only the right side frame segment 40b and its
surroundings.
[0499] In the sixth embodiment, the pressure receiving member 41 is
suspended by the upper wire rod 43 and the lower wire rod 44
between the side frame segments 40b. In contrast, the pressure
receiving member 41 of the third modification is suspended by a
framed wire rod 103, right and left spring wire rods 104, and right
and left lower coupling wire rods 105 between the side frame
segments 40b. The framed wire rod 103, the right and left spring
wire rods 104, and the right and left lower coupling wire rods 105
are disposed inside the backrest 4.
[0500] The backrest 4 includes a deformation controlling means for
controlling the extent of deformation of the extending parts 41b.
The deformation controlling means includes mounting wire rods 106.
Each mounting wire rod 106 is formed by bending a metal wire into a
substantially V shape. The mounting wire rods 106 are an example of
the contact members. Each mounting wire rod 106 has ends fixed to
the vertical pipe segment 40b1 near the top end of the main body
part 40b2 of each side frame segment by welding.
[0501] As shown in FIG. 48, the framed wire rod 103 includes a
substantially U-shaped upper wire rod 103a and a lower wire rod
103b swaged with metal sleeves 103c. The framed wire rod 103 is
disposed on the rear of the pressure receiving member 41 within the
backrest frame 40 (between the left and right side frame segments
40b).
[0502] The upper wire rod 103a includes right and left vertical
wire segments 103a1, a horizontal wire segment 103a2 and wire
connectors 103a3. The vertical wire segments 103a1 extend
vertically. The horizontal wire segment 103a2 extends in the
right-left direction to couple the top ends of the right and left
vertical wire segments 103a1. The wire connectors 103a3 are
disposed at the right and left corners at which the vertical wire
segments 103a1 and the horizontal wire segment 103a2 are coupled.
The wire connectors 103a3 are bent outward in the right-left
direction.
[0503] Similarly to the upper wire rod 103a, the lower wire rod
103b also includes right and left vertical wire segments 103b1, a
horizontal wire segment 103b2, and wire connectors 103b3. The
vertical wire segments 103b1 extend vertically. The horizontal wire
segment 103b2 extends in the right-left direction to couple the
bottom ends of the right and left vertical wire segments 103b1. The
wire connectors 103b3 are formed at the right and left corners at
which the vertical wire segments 103b1 and the horizontal wire
segment 103b2 are coupled. The wire connectors 103b3 are bent
outward in the right-left direction.
[0504] The pressure receiving member 41 primarily includes a main
body part 41a and right and left extending parts 41b. Each
extending part 41b can resiliently bend and deform in the
front-back direction along the connecting line between the
extending part 41b and the main body part 41a. The main body part
41a includes engaging claws 41s, 41t, and 41u for fixing the
pressure receiving member 41 to the framed wire rod 103. The
engaging claws 41s, 41t and 41u are integrated with the main body
part 41a. The engaging claws 41s to 41u each have a substantially
U-shape in cross-sectional view. More specifically, each engaging
claw extends backward from the rear surface of the main body part
41a, bends, extends along the rear surface of the main body part
41a, and bends frontward. When the engaging claw 41s to 41u are
engaged with the framed wire rod 103, the framed wire rod 103 is
kept by the engaging claws 41s to 41u between the rear surface of
the main body part 41a and the engaging claws 41s to 41u. The
single engaging claw 41s is provided near the top end of the main
body part 41a at the horizontal center. The engaging claw 41s is
engaged with the horizontal wire segment 103a2 of the upper wire
rod 103a. The two engaging claws 41t are formed in the upper
portion of the main body part 41a side by side in the right-left
direction. The engaging claws 41t are engaged with the vertical
wire segments 103a1 of the upper wire rod 103a. The two engaging
claws 41u are formed near the bottom end of the main body part 41a
side by side in the right-left direction. The engaging claws 41u
are engaged with the horizontal wire segment 103b2 of the lower
wire rod 103b.
[0505] The spring wire rods 104 are resilient coupling members
having a spring property. The spring wire rods 104 are each formed
by winding a metal wire rod spirally. Each spring wire rod 104 has
the horizontally inner end coupled to the corresponding wire
connector 103a3 of the upper wire rod 103a. Each spring wire rod
104 has the horizontally outer end coupled to the corresponding
mounting wire rod 106. The spring wire rods 104 thereby couple the
upper portion of the pressure receiving member 41 to the left and
right side frame segments 40b.
[0506] Each lower coupling wire rod 105 has the horizontally inner
end coupled to the corresponding wire connector 103b3 of the lower
wire rod 103b by swaging with the metal sleeve 103d. The lower
coupling wire rod 105 has the horizontally outer end latched with
mounting holes 41b8 formed in the lower part of the main body part
40b2 of the side frame segment (See FIG. 47). The lower coupling
wire rods 105 thereby couple the lower portion of the pressure
receiving member 41 to the left and right side frame segments
40b.
[0507] In front view, the framed wire rod 103 is disposed inside of
the extending parts 41b in the right-left direction within the
vertical range of the extending parts 41b, that is, on the rear of
the main body part 41a. The engaging claw 41s, which couples the
pressure receiving member 41 to the horizontal wire segment 103a2
(horizontally extending portion of the framed wire rod 103), and
the engaging claws 41t, which couple the pressure receiving member
41 to the vertical wire segments 103a1 (vertically extending parts
of the framed wire rod 103) are both within the vertical range of
the extending parts 41b.
[0508] The third modification having such a configuration can also
support a wide range of the upper body of the occupant with the
main body part 41a and the extending parts 41b and thus stabilizes
the support of the upper body of the occupant. As shown in FIG. 49,
at a predetermined amount of bending of the extending parts 41b,
the front edges of the extending parts 41b come into contact with
the mounting wire rods 106. This contact allows the mounting wire
rods 106 to control the extent of deformation of the extending
parts 41b. This configuration can preclude excess deformation of
the extending parts 41b and thus stabilizes the support of the
upper body of the occupant.
[0509] In the third modification, the framed wire rod 103 is
disposed on the rear of the main body part 41a within the vertical
range of the extending parts 41b. Thus, the framed wire rod 103 can
stabilize the support of the main body part 41a and can further
stabilize the support of the upper body of the occupant.
[0510] In the third modification, the engaging claw 41s, which is
engaged with the horizontal wire segment 103a2, and the engaging
claws 41t, which are engaged with the vertical wire segments 103a1,
are within the vertical range of the extending parts 41b. This
configuration can enhance the mounting rigidity of the pressure
receiving member 41 to the framed wire rod 103 at the height of the
extending parts 41b. The enhanced mounting rigidity stabilizes the
posture of the extending parts 41b and further stabilizes the
support of the upper body of the occupant.
[0511] At rear-end collision by another vehicle, the upper body of
an occupant is pressed against the cushion pad 48 to significantly
deform the near-center portion of the cushion pad 48. If the
impulsive force is so large that a backward load exceeding a
predetermined value is applied to the pressure receiving member 41
by the upper body of the occupant via the cushion pad 48, the
spring wire rods 104 elongate or the lower coupling wire rods 105
bends. The pressure receiving member 41 then moves backward
relative to the left and right side frame segments 40b and the
upper body of the occupant deeply sinks into the backrest 4. As a
result, the head of the occupant rapidly approaches the headrest 6
and is supported thereby, thus protecting the head and the neck
region of the occupant from the impact of the collision of the rear
surface of the vehicle.
[0512] In this embodiment, a large backward load applied to the
pressure receiving member 41 causes the spring wire rods 104,
having a spring property (resilience), to elongate and deform more
significantly than the lower coupling wire rods 105. This causes
the upper portion of the pressure receiving member 41 to retreat
more significantly than the lower portion of the pressure receiving
member 41. This configuration allows the breast portion, i.e., the
upper portion of the upper body of the occupant, to sink more
rapidly and deeply than the waist portion, i.e., the lower portion
of the upper body of the occupant relative to the backrest 4. As a
result, the head of the occupant, which is close to the breast of
the occupant, rapidly approaches the headrest 6 and is supported
thereby, thus protecting the head and the neck region of the
occupant more effectively.
Fourth Modification of Sixth Embodiment
[0513] In the sixth embodiment, the extending parts 41b are formed
only at positions corresponding to the breast height of the
occupant, but the present invention should not be limited to this
configuration. For example, the extending parts 41b may be formed
only at positions corresponding to the waist height of the
occupant. Extending parts other than the extending parts 41b formed
at the breast-height positions of the occupant may be formed at the
waist-height positions of the occupant. If both the breast-height
extending parts and the waist-height extending parts are provided,
they may be formed independently or coupled with each other.
Modification 5 of Sixth Embodiment
[0514] In this embodiment, the coupling portions (claws 41c)
between the pressure receiving member 41 and the upper wire rod 43
are within the vertical range of the extending parts 41b, but the
present invention should not be limited to this configuration. For
example, with reference to FIG. 42, the claws 41c may be disposed
outside the vertical range of the extending parts 41b. This is also
applied to the engaging claws 41s and 41t according to the third
modification. The coupling between the pressure receiving member 41
and the wire rod should not be limited to the use of the claws. For
example, pairs of through-holes are disposed in a row in the
right-left direction or in the up-down direction on the pressure
receiving member 41 and the wire rod is fixed with ties extending
through the through-holes.
Sixth Modification of Sixth Embodiment
[0515] In the first modification, the pan frames 101 are an example
of the counter plates, but the present invention should not be
limited to this configuration. For example, the counter plates may
be the main body parts 40b2 of the side frame segments. In the
sixth embodiment or the first and second modifications thereof, the
supporting wire rods 100 and the pan frames 101 are exemplary
contact members, but the present invention should not be limited to
this configuration. The contact members may be, for example, the
side frame segments 40b, which constitute right and left frames of
the backrest 4.
Seventh Modification of Sixth Embodiment
[0516] In the third modification, the framed wire rod 103 is
composed of two wire rods (upper wire rod 103a and lower wire rod
103b), but the present invention is not limited to this
configuration. The framed wire rod 103 may be composed of, for
example, a single wire.
Additional Statement on Sixth Embodiment
[0517] As is evident from the above description of the sixth
embodiment and its modifications, the description of the sixth
embodiment and its modifications include various disclosures on
technical ideas in addition to the aspect of the invention
described in the following notes.
Note 1.
[0518] A vehicle seat including a bottom seat and a backrest,
wherein the backrest includes a plate-like pressure receiving
member that supports load from an occupant,
[0519] wherein the pressure receiving member includes a main body
part and extending parts, the main body part facing a rear surface
of an upper body of the occupant and the extending parts extending
from right and left edges of the main body part outward in the
right-left direction and being resiliently deformable in the
front-back direction, and
[0520] wherein the backrest has deformation controlling means for
controlling an extent of deformation of the extending parts.
Note 2.
[0521] The vehicle seat according to note 1, wherein the
deformation controlling means is a contact member with which a
front edge of each extending part comes into contact at a
predetermined amount of deformation of the extending part.
Note 3.
[0522] The vehicle seat according to note 2, wherein the backrest
includes right and left side frame segments constituting right and
left frames of the backrest, each of the side frame segments having
a wire member attached to the side frame segment, and
[0523] wherein each contact member is the wire member.
Note 4.
[0524] The vehicle seat according to note 3, wherein a front edge
of each extending part is bent backward to form an engaging
portion, the engaging portion being caught by the wire member at
the time of contact of the front edge with the wire member.
Note 5.
[0525] The vehicle seat according to note 2, wherein the backrest
includes right and left counter plates facing each other in the
right-left direction and disposed outside the pressure receiving
member in the right-left direction, and
[0526] wherein the contact members are the counter plates.
Note 6.
[0527] The vehicle seat according to note 5, wherein each counter
plate is disposed such that the front edge of the extending part
slides on the counter plate and wherein each counter plate includes
a controlling portion with which the front edge of the extending
part sliding backward comes into contact.
Note 7.
[0528] The vehicle seat according to note 1, wherein
[0529] the backrest includes right and left counter plates facing
each other in the right-left direction,
[0530] each extending part is curved into an arch in a horizontal
cross sectional view,
[0531] the deformation controlling means is formed in each counter
plate and is a hole into which the front edge of the extending part
is inserted.
Note 8.
[0532] The vehicle seat according to one of notes 1 to 7, wherein
the backrest includes a backrest frame constituting part of the
backrest and a coupling wire put across the backrest frame and
coupling the pressure receiving member to the backrest frame,
and
[0533] wherein a coupling portion between the pressure receiving
member and the coupling wire is within a vertical range of the
extending parts.
Note 9.
[0534] The vehicle seat according to one of notes 1 to 6, wherein
the backrest includes a backrest frame constituting part of the
backrest and a coupling wire put across the backrest frame and
coupling the pressure receiving member to the backrest frame,
and
[0535] wherein the front edges of the extending parts do not
overlap with the coupling wire in front view.
(a) Advantageous Effects of Present Invention Described in Note
1
[0536] The central main body part and the right and left extending
parts support a wide range of the upper body of the occupant and
thus stabilize the support of the upper body of the occupant. The
deformation controlling means can control the extent of deformation
of the extending parts. This configuration can prevent excess
deformation of the extending parts during a normal seating, thereby
stabilizing the support of the upper body of the occupant.
(b) Advantageous Effects of Present Invention Described in Note
2
[0537] The contact between the front edges of the extending parts
and the contact members can prevent excess deformation of the
extending parts to stabilize the support of the upper body of the
occupant, while allowing the deformation of the extending parts
until the front edges of the extending parts come into contact with
the contact members. Such a configuration ensures a necessary
extent of deformation for the extending parts.
(c) Advantageous Effects of Present Invention Described in Note
3
[0538] Unlike a configuration in which the portions that come into
contact with the front edges of the extending parts are provided on
the side frame segments themselves to use them as contact members,
the present invention described in Note 3 eliminates the necessity
for forming a contact portion on each side frame segment. This
helps prevent the increase in size of the side frame segments and
improves the versatility of the side frame segments.
(d) Advantageous Effects of Present Invention Described in Note
4
[0539] The engaging portions engaged with the wire members can
control the positions of the front edges of the extending parts
more strictly. Such a strict control can effectively prevent excess
deformation of the extending parts and further stabilize the
support of the upper body of the occupant.
(e) Advantageous Effects of Present Invention Described in Note
5
[0540] The front edges of the extending parts come into contact
with surfaces. Such a contact through surfaces can maintain the
contact between the front edges and the counter plates and ensure
the prevention of excess deformation of the extending parts. This
configuration can further stabilize the support of the upper body
of the occupant.
(f) Advantageous Effects of Present Invention Described in Note
6
[0541] The sliding contact between the front edges of the extending
parts and the counter plates allows deformation of the extending
parts until the front edges of the extending parts come into
contact with controlling portions, thus ensuring a necessary extent
of deformation for the extending parts. The present invention
described in Note 6 can prevent excess deformation of the extending
parts after the contact between the front edges of the extending
parts and the controlling portions. Such a configuration can
further stabilize the support of the upper body of the
occupant.
(g) Advantageous Effects of Present Invention Described in Note
7
[0542] The front edges of the extending parts inserted into the
through-holes formed in the counter plates prevent the movement of
the front edges of the extending parts and thus excess deformation
of the extending parts is prevented. This configuration can
stabilize the support of the upper body of the occupant.
(h) Advantageous Effects of Present Invention Described in Note
8
[0543] The pressure receiving member is coupled to the backrest
frame at the height of the extending parts via the coupling wire
rod. This configuration stabilizes the posture of the extending
parts and thus can prevent excess deformation of the extending
parts with the deformation controlling means, thereby stabilizing
the support of the upper body of the occupant.
(i) Advantageous Effects of Present Invention Described in Note
9
[0544] The interference does not occur between the front edges of
the extending parts and the coupling wire rods even at a front-back
movement of the front edges due to deformation of the extending
parts.
Seventh Embodiment
[0545] FIG. 50 is a perspective view of a backrest frame 40 of a
seat backrest of the seventh embodiment of the present invention.
The same parts between a seat according to the seventh embodiment
and the seat 1 according to the first embodiment are given the same
reference numerals. If the same parts are provided in the same
manner, the explanation thereof will be omitted if possible. The
following description focuses on differences between the seat
according to the seventh embodiment and the seat 1 according to the
first embodiment.
[0546] Differences between the seat according to the seventh
embodiment and the seat 1 according to the first embodiment lie in
the backrest 4. More specifically, the seat according to the
seventh embodiment includes a lumbar support plate 130 in front of
the main body part 41a of the pressure receiving member 41. In
contrast, the seat 1 according to the first embodiment does not
include a member equivalent to the lumbar support plate 130 in
front of the pressure receiving member 41. The backrest of the seat
according to the seventh embodiment is provided in the same manner
as that of the seat according to the first embodiment, except for
the lumbar support plate 130, which is provided in front of the
pressure receiving member 41.
[0547] The seat according to the seventh embodiment includes slide
rails, a bottom seat, a bottom seat, a recliner mechanism and a
headrest, which are provided in the same manner as the slide rails
2, the bottom seat 3, the recliner mechanism 5 and the headrest 6
of the seat 1 according to the first embodiment.
[0548] The lumbar support plate 130 and relevant items will now be
described.
[0549] The lumbar support plate 130 is resiliently bent. The lumbar
support plate 130 is disposed in front of the main body part 41a
such that it faces and is overlaid on the main body part 41a. The
lumbar support plate 130 is attached to the main body part 41a such
that the top end and the bottom end of the lumbar support plate 130
are vertically movable relative to the main body part 41a. At an
upward movement of the bottom end of the lumbar support plate 130
relative to the pressure receiving member 41 without any movement
of the top end of the lumbar support plate 130, the lumbar support
plate 130 is curved such that it protrudes forward. At a downward
movement of the bottom end of the lumbar support plate 130 relative
to the pressure receiving member 41 without any movement of the top
end of the lumbar support plate 130, the curved lumbar support
plate 130 is vertically elongated to less protrude forward. At a
concurrent vertical movement of the top end and the bottom end of
the lumbar support plate 130, the lumbar support plate 130 moves
vertically relative to the pressure receiving member 41 while
retaining the extent of the curve (curvature).
[0550] With reference to FIGS. 50 to 52, the lumbar support plate
130 will now be described in detail. FIG. 51 is a front perspective
view of the lumbar support plate 130. FIG. 52 is a rear perspective
view of the lumbar support plate 130.
[0551] The front surface of the lumbar support plate 130 is
provided with a recess 131 at the horizontal center. The recess 131
is formed into a stripe in front view. The stripe extends
vertically. The front surface of the lumbar support plate 130
includes a central part 132 and side parts 133. The central part
132 is formed into the recess 131. The side parts 133 are the right
and left sides of the recess 131. A step is formed between the
central part 132 and each side 133. The central part 132 is
recessed backward by the one step relative to the side parts
133.
[0552] A movable member 134 is provided in the lower central
portion (in the right-left direction) of the lumbar support plate
130. Support members 135 are provided on the right and left sides
of the movable member 134. More specifically, two right and left
notches 136 are formed from the bottom end of the lumbar support
plate 130 along the right and left edges of the recess 131. The
lower portion of the lumbar support plate 130 is divided into the
movable member 134 and the support members 135 by these notches
136.
[0553] The portion between the notches 136 is the movable member
134. The right and left sides of the movable member 134 are the
support members 135. Each notch 136 extends from the bottom end of
the lumbar support plate 130 to a point slightly below the vertical
center of the lumbar support plate 130. The upper end of each notch
136 is slightly below the vertical center of the lumbar support
plate 130. An area on the lumbar support plate 130 between the part
slightly above the upper ends of the notches 136 and the part
slightly below the upper ends of the notches 136 is a pressure area
137. As shown with the two-dot chain lines in FIG. 50, the strip
area extending in the right-left direction is the pressure area
137.
[0554] The support member 135 is curved so as to protrude
diagonally downward to the front in side view.
[0555] With reference to FIGS. 50 to 54, how the lumbar support
plate 130 and the pressure receiving member 41 are assembled will
now be described. FIG. 53 is a rear perspective view of an assembly
of the lumbar support plate 130 and the pressure receiving member
41. FIG. 54 is a front perspective view of the pressure receiving
member 41.
[0556] As shown in FIG. 54, a recess 151 is formed in the upper
portion of the front surface of the main body part 41a of the
pressure receiving member 41. The recess 151 has a vertically long
rectangular shape (strip) in front view. Slits 152 are formed on
the right and left sides of the recess 151. As shown in FIGS. 53
and 54, the right and left slits 152, formed on the sides of the
recess 151, penetrate to the rear. The slits 152 extend
vertically.
[0557] As shown in FIG. 51, a slider 138 is provided at the top end
of the rear surface of the lumbar support plate 130. The slider 138
is convex. The slider 138 is provided at the center (in the
right-left direction) of the lumbar support plate 130. A sliding
bar 139 is provided on each of the right and left sides of the
slider 138. The left sliding bar 139 extends leftward from the left
surface of the slider 138. The right sliding bar 139 extends
rightward from the right surface of the slider 138.
[0558] As shown in FIG. 50, the slider 138 is fit to the recess 151
to cause the right and left sides of the recess 151 to constrain
the right-left movement of the slider 138. The sliding bars 139 fit
to the slits 152 to cause the slits 152 to constrain the
anteroposterior movement of the sliding bars 139. This
configuration allows the slider 138 and the sliding bar 139 to move
vertically. Thus, the lumbar support plate 130 is mounted on the
main body part 41a such that the top end of the lumbar support
plate 130 is movable vertically relative to the main body part
41a.
[0559] As shown in FIG. 54, the main body part 41a of the pressure
receiving member 41 has a guide hole 153 in its lower part. The
guide hole 153 has a vertically long rectangular shape. Receiving
recesses 154 are formed on the front surface of the main body part
41a at the right and left edges of the guide hole 153. The
receiving recesses 154 extend vertically along the right and left
edges of the guide hole 153.
[0560] As shown in FIG. 52, sliders 140 are disposed in the area
from the lower end of the rear surface of the lumbar support plate
130 to the bottom end surface of the lumbar support plate 130. More
specifically, the sliders 140 are disposed in the area from the
right and left sides of the lower end of the rear surface of the
movable member 134 to the bottom end surface of the movable member
134. The area from the rear to bottom surface of each slider 140
has a cylinder face around the horizontal central axis. As shown in
FIG. 51, a convex slider 141 is provided on the bottom end surface
of the lumbar support plate 130, more specifically, on the bottom
end surface of the movable member 134.
[0561] As shown in FIG. 50, each slider 140 fits in the receiving
recess 154 and comes into contact with the bottom of the receiving
recess 154 to cause the receiving recess 154 to constrain the
right-left movement and backward movement of the slider 140. When
the movable member 134 is erected relative to the front surface of
the lumbar support plate 130, the slider 141 is fit to the guide
hole 143 to cause the guide hole 153 to constrain the horizontal
movement of the slider 141. This configuration allows the sliders
141 and 140 to be move vertically. Thus, the lumbar support plate
130 is attached to the main body part 41a such that the bottom end
of the lumbar support plate 130 (more specifically, the bottom end
of the movable member 134) can move vertically. Inner wire rods 173
and 183, which are described in detail later, prevent the bottom
end of the movable member 134 from being away from the front
surface of the pressure receiving member 41 frontward.
[0562] As shown in FIGS. 50, 52, and 53, the lumbar support plate
130 is bent by a control cable 161. The control cable 161 includes
an outer tube 162 and an inner wire rod 163.
[0563] As shown in FIGS. 52 and 53, the outer tube 162 is routed
from the top end of the lumbar support plate 130 through the rear
surface of the lumbar support plate 130. The outer tube 162 has an
end 162a directed downward. The end 162a is fixed to the rear
surface of the lumbar support plate 130 above the movable member
134 by an engagement piece 162b.
[0564] The inner wire rod 163 extends through the outer tube 162.
The inner wire rod 163 is drawn downward from the end 162a of the
outer tube 162. The inner wire rod 163 has one end coupled to the
rear surface of the movable member 134. The coupling portion
between the inner wire rod 163 and the movable member 134 is below
the end 162a of the outer tube 162. The coupling portion between
the inner wire rod 163 and the movable member 134 is preferably in
the lower portion of the movable member 134 below the upper ends of
the notches 136.
[0565] The engagement piece 162b protrudes from the rear surface of
the lumbar support plate 130. The recess 151 of the pressure
receiving member 41 has an opening 155. The engagement piece 162b
is inserted into the opening 155 and can move vertically along the
opening 155. This configuration prevents the interference between
the engagement piece 162b and the pressure receiving member 41.
[0566] The inner wire rod 163 has the other end drawn from the
other end of the outer tube 162. The drawn portion is wound around,
for example, a winding mechanism (or an operating part for
bending). The inner wire rod 163 can be wound around the winding
mechanism or unwound from the winding mechanism. The winding
mechanism is, for example, disposed on a side of the backrest 4 or
a side of the bottom seat 3.
[0567] As shown in FIGS. 50 and 53, the lumbar support plate 130 is
lifted up by a control cable 171 and lowered by a control cable
181. The control cable 171 includes an outer tube 172 and an inner
wire rod 173. The control cable 181 includes an outer tube 182 and
an inner wire rod 183.
[0568] As shown in FIG. 53, the outer tubes 172 and 182 are routed
from the top end of the pressure receiving member 41 through the
rear surface of the pressure receiving member 41. The outer tubes
172 and 182 are fixed to the rear surface of the pressure receiving
member 41 by an engagement piece 170 formed on the rear surface of
the pressure receiving member 41. The outer tubes 172 and 182 have
ends 172a and 182a directed downward and fixed to the rear surface
of the lumbar support plate 130 above the guide hole 153 by
engagement pieces 172b and 182b, respectively.
[0569] The inner wire rod 173 extends through the outer tube 172.
The inner wire rod 173 is drawn from the end 172a of the outer tube
172. The inner wire rod 173 has one end coupled to the bottom end
of the movable member 134, more specifically, to the bottom end of
the rear surface of the movable member 134.
[0570] The coupling portion between the inner wire rod 173 and the
movable member 134 is below the end 172a of the outer tube 172.
[0571] The inner wire rod 183 extends through the outer tube 182.
The inner wire rod 183 is drawn from the end 182a of the outer tube
182 and is hooked by a wire hook 189 provided on the bottom end of
the pressure receiving member 41 and folded back toward the front
surface of the pressure receiving member 41 at the wire hook 189.
The inner wire rod 183 extends upward from the wire hook 189 and
has the tip coupled to the bottom end of the movable member 134.
More specifically, as shown in FIG. 50, one end of the inner wire
rod 183 is coupled to the bottom end of the front surface of the
movable member 134.
[0572] The coupling portion between the inner wire rod 183 and the
movable member 134 is above the wire hook 189.
[0573] The inner wire rods 173 and 183 have other ends drawn from
the other ends of the outer tubes 172 and 182, respectively. The
drawn portions are wound around, for example, by a winding
mechanism (or an operating part for up-down movement). The inner
wire rod 173 can be wound around the winding mechanism while the
inner wire rod 183 can be unwound from the winding mechanism.
Conversely, the inner wire rod 173 can be unwound from the winding
mechanism while the inner wire rod 183 can be wound around the
winding mechanism. The winding mechanism is disposed, for example,
on a side of the backrest 4 or a side of the bottom seat 3.
[0574] The operation and use of the seat according to the seventh
embodiment will now be described.
[0575] The inner wire rod 163 wound around the winding mechanism
causes the inner wire rod 163 drawn from the end 162a of the outer
tube 162 to be drawn back into the outer tube 162 to move the tip
of the inner wire rod 163 closer to the end 162a of the outer tube
162. This, in turn, causes the bottom end of the movable member 134
to be pulled up by the inner wire rod 163 and move up along the
front surface of the main body part 41a of the pressure receiving
member 41. As the bottom end of the movable member 134 moves up,
the movable member 134 gets erected relative to the front surface
of the main body part 41a. This causes the lumbar support plate 130
to be resiliently curved into a mountain shape. As the curvature of
the lumbar support plate 130 increases, the pressure area 137
travels frontward more away from the front surface of the pressure
receiving member 41. The pressure area 137 of the lumbar support
plate 130 presses a back receiving part 48a of the cushion pad 48
forward.
[0576] The inner wire rod 163 unwound from the winding mechanism
loosens the inner wire rod 163. Force to restore the lumbar support
plate 130 to an original shape is applied to the lumbar support
plate 130 to reduce the height of mountain of the lumbar support
plate 130. As the curvature of the lumbar support plate 130
decreases, the movable member 134 is more inclined toward the front
surface of the main body part 41a, and the bottom end of the
movable member 134 moves downward along the main body part 41a of
the pressure receiving member 41. The inner wire rod 163 is drawn
from the end 162a of the outer tube 162. The pressure area 137
approaches the front surface of the pressure receiving member 41
and the back receiving part 48a of the cushion pad 48 retreats
backward.
[0577] As described above, the curvature of the lumbar support
plate 130 can be adjusted by adjusting the position of the bottom
end of the movable member 134 with the control cable 161. A
curvature that best suits the shapes of the back and waist of the
occupant can be found through the adjustment. Locking the winding
mechanism prevents winding or unwinding of the inner wire rod 163,
thus retaining the curvature of the lumbar support plate 130.
[0578] The inner wire rod 173 is wound around the winding mechanism
while the inner wire rod 183 is unwound from the winding mechanism
to loosen the inner wire rod 183. This, in turn, causes the bottom
end of the movable member 134 to be pulled up by the inner wire rod
173 and move up along the front surface of the main body part 41a
of the pressure receiving member 41. As the bottom end of the
movable member 134 moves upward, the top end of the lumbar support
plate 130 also moves upward along the front surface of the main
body part 41a of the pressure receiving member 41 and the entire
lumbar support plate 130 moves upward while retaining the curvature
thereof.
[0579] The inner wire rod 183 is wound around the winding mechanism
while the inner wire rod 173 is unwound from the winding mechanism
to loosen the inner wire rod 173. This, in turn, causes the bottom
end of the movable member 134 to be pulled down by the inner wire
rod 183 and move downward along the front surface of the main body
part 41a of the pressure receiving member 41. As the bottom end of
the movable member 134 moves downward, the top end of the lumbar
support plate 130 also moves downward along the front surface of
the main body part 41a of the pressure receiving member 41 and the
entire lumbar support plate 130 moves upward while retaining the
curvature thereof.
[0580] As shown above, the vertical position of the lumbar support
plate 130 is adjusted with the control cables 171 and 181. This
adjustment allows the vertical position of the pressure area 137 of
the lumbar support plate 130 to be aligned with the waist height of
the occupant. Locking the winding mechanism prevents winding or
unwinding of the inner wire rods 173 and 183, thus retaining the
vertical position of the lumbar support plate 130.
[0581] In the seat described above, the adjustment of the curvature
and the vertical position of the lumbar support plate 130 can bring
the front surface of the backrest 4 into a close contact with the
back of the occupant in conformance with the shape thereof. This
improves seating comfort.
[0582] The lumbar support plate 130, which is assembled to the
pressure receiving member 41, moves together with the pressure
receiving member 41 in the front-back direction relative to the
backrest frame 40. Thus, the lumbar support plate 130 does not
prevent the backward movement of the occupant and can provide a
satisfactory cushioning performance.
[0583] The recess 131, formed on the front surface of the lumbar
support plate 130 at the horizontal center, makes a portion of the
cushion pad 48 in front of the recess 131 less compressed than
other part of the cushion pad 48. This ensures a satisfactory
cushioning performance of a portion of the cushion pad 48 in
contact with the spine of the occupant and improves seating
comfort.
[0584] Since the lower portion of the lumbar support plate 130 is
divided, the movement of the hip or back of an occupant while the
bottom end of the movable member 134 is being fixed causes greater
deformation of the right and left sides of the lumbar support plate
130 than the central portion. This enhances the ability of the
lumbar support plate 130 to deform in conformity with changes in
the posture of the occupant and thus improves the seating
comfort.
Eighth Embodiment
[0585] FIG. 55 is a perspective view of a backrest frame 40 of a
seat according to the eighth embodiment of the present invention.
The same parts between the seat according to the eighth embodiment
and the seat 1 according to the first embodiment are given the same
reference numerals. If the same parts are provided in the same
manner, the explanation thereof will be omitted if possible. The
following description focuses on differences between the seat
according to the eighth embodiment and the seat 1 according to the
first embodiment.
[0586] Differences between the seat according to the eighth
embodiment and the seat 1 according to the first embodiment lie in
the backrest 4. More specifically, the seat according to the eighth
embodiment is provided with a lumbar support plate 230 in front of
the main body part 41a of the pressure receiving member 41. In
contrast, the seat 1 according to the first embodiment does not
include a member equivalent to the lumbar support plate 230 in
front of the pressure receiving member 41. The backrest of the seat
according to the seventh embodiment is provided in the same manner
as that of the seat according to the first embodiment, except for
the lumbar support plate 230, which is provided in front of the
pressure receiving member 41.
[0587] The seat according to the seventh embodiment includes slide
rails, a bottom seat, a bottom seat, a recliner mechanism, and a
headrest, which are provided in the same manner as the slide rails
2, the bottom seat 3, the recliner mechanism. 5, and the headrest
6, which are provided in the seat 1 according to the first
embodiment.
[0588] The lumbar support plate 230 and relevant items will now be
described.
[0589] The lumbar support plate 230 is resiliently bent. The lumbar
support plate 230 is disposed in front of the main body part 41a
such that it faces and is overlaid on the front surface of the main
body part 41a. The lumbar support plate 230 is attached to the main
body part 41a such that the top end and the bottom end of the
lumbar support plate 230 are vertically movable relative to the
main body part 41a. At an upward movement of the bottom end of the
lumbar support plate 230 relative to the pressure receiving member
41 without any movement of the top end of the lumbar support plate
230, the lumbar support plate 230 is curved such that it protrudes
forward. At a downward movement of the bottom end of the lumbar
support plate 230 relative to the pressure receiving member 41
without any movement of the top end of the lumbar support plate
230, the curved lumbar support plate 230 is vertically elongated to
less protrude forward. At a concurrent vertical movement of the top
end and the bottom end of the lumbar support plate 230, the lumbar
support plate 230 moves vertically relative to the pressure
receiving member 41 while retaining the extent of the curve
(curvature).
[0590] With reference to FIGS. 55 to 57, the lumbar support plate
230 will now be described in detail. FIG. 56 is a front perspective
view of the lumbar support plate 230. FIG. 57 is a rear perspective
view of the lumbar support plate 230.
[0591] A plate-like movable member 234 is provided in the lower
portion of the rear surface of the lumbar support plate 230. A
plate-like support member 235 is provided in the lower portion of
the front surface of the lumbar support plate 230. More
specifically, the lower portion of the lumbar support plate 230 is
divided into two parts in the front-back direction: the plate-like
support member 235 in front and the plate-like movable member 234
in rear. Atop end 235a of the support member 235 and a top end 234a
of the movable member 234 are coupled such that the support member
235 and the movable member 234 face each other in the front-back
direction. An area on the lumbar support plate 230 from slightly
above the top end 235a of the support member 235 and the top end
234a of the movable member 234 to slightly below the ends 235a and
234a is referred to as a pressure area 237. As shown with the
two-dot chain lines in FIG. 55, a strip area 237 extending in the
right-left direction is the pressure area 237.
[0592] The support member 235 is curved so as to protrude
diagonally downward to the front in side view.
[0593] The lumbar support plate 230 has an opening 231 penetrating
in the front-back direction at the horizontal center thereof. The
opening 231 is vertically long. The opening 231 starts above the
top end 235a of the support member 235 and the top end 234a of the
movable member 234 and ends below the top end 235a and the top end
234a thereof in the support member 235 and the movable member
234.
[0594] With reference to FIGS. 55 to 59, how the lumbar support
plate 230 and the pressure receiving member 41 are assembled will
now be described. FIG. 58 is a front perspective view of an
assembly of the lumbar support plate 230 and the pressure receiving
member 41. FIG. 59 is a rear perspective view of the assembly of
the lumbar support plate 230 and the pressure receiving member
41.
[0595] As shown in FIG. 59, the main body part 41a of the pressure
receiving member 41 has an opening 251 in the lower portion
thereof. The opening 251 has a vertically long rectangular shape
(strip) in front view.
[0596] As shown in FIGS. 57 and 59, a convex slider 238 is provided
at the bottom end of the rear surface of the lumbar support plate
230, more specifically, at the bottom end of the rear surface of
the movable member 234. The slider 238 is provided at the
horizontal center of the lumbar support plate 230. Sliding bars 239
are provided on the right and left sides of the rear surface of the
slider 238. The left sliding bar 239 extends leftward from the
slider 238. The right sliding bar 239 extends rightward from the
slider 238.
[0597] As shown in FIG. 59, the slider 238 is fit to the opening
251 to cause the opening 231 to constrain the right-left movement
of the slider 238. The sliding bars 239 come into contact with the
rear surface of the main body part 41a of the pressure receiving
member 41 on the right and left sides of the opening 251. The rear
surface of the movable member 234 comes into contact with the front
surface of the main body part 41a of the pressure receiving member
41. The main body part 41a of the pressure receiving member 41 is
disposed between the sliding bars 239 and the movable member 234 to
cause the movable member 234 to constrain an anteroposterior
movement of the sliding bars 239 and the slider 238. The lumbar
support plate 230 is attached to the main body part 41a such that
the sliding bars 239 can slide vertically along the rear surface of
the main body part 41a of the pressure receiving member 41, the
bottom end of the rear surface of the movable member 234 can slide
vertically along the rear surface of the main body part 41a of the
pressure receiving member 41, and such that the bottom end of the
lumbar support plate 230 can move vertically relative to the main
body part 41a.
[0598] As shown in FIG. 58, the main body part 41a of the pressure
receiving member 41 has a receiving recess 254 in the upper portion
thereof. The receiving recess 254 has a rectangular shape.
[0599] As shown in FIG. 57, a slider 240 is provided in the area
from the upper end of the rear surface of the lumbar support plate
230 to the top end surface of the lumbar support plate 230. The
area from the rear to upper surface of the slider 240 has a
cylinder face around a horizontal central axis.
[0600] As shown in FIGS. 55, 58, and 59, the slider 240 fits in the
receiving recess 254 and comes into contact with the bottom of the
receiving recess 254 to cause the receiving recess 154 to constrain
horizontal and backward movements of the slider 240. This allows
the slider 240 to move vertically, and the lumbar support plate 230
is attached to the main body part 41a such that the top end of the
lumbar support plate 230 can move vertically. Inner wire rods 273
and 283, which are described in detail later, prevent the top end
of the lumbar support plate 230 from being away from the front
surface of the pressure receiving member 41 frontward.
[0601] As shown in FIGS. 55, 57, 58, and 59, the lumbar support
plate 230 is bent by a control cable 261. The control cable 261
includes an outer tube 262 and an inner wire rod 263.
[0602] As shown in FIG. 57, the outer tube 262 is routed from the
top end of the lumbar support plate 230 through the rear surface of
the lumbar support plate 230. The outer tube 262 has an end 262a
directed downward. The end 262a is fixed to the rear surface of the
lumbar support plate 230 above the movable member 234 by an
engagement piece 262b.
[0603] The inner wire rod 263 extends through the outer tube 262.
The inner wire rod 263 is drawn downward from the end 262a of the
outer tube 262. The inner wire rod 263 has one end coupled to the
rear surface of the movable member 234 below the top end of the
movable member 234. More specifically, the end of the inner wire
rod 263 is coupled to the bottom end of the rear surface of the
movable member 234.
[0604] The inner wire rod 263 has other end drawn from the other
end of the outer tube 262. The drawn portion is wound around, for
example, a winding mechanism (or an operating part for bending).
The inner wire rod 263 can be wound around the winding mechanism or
unwound from the winding mechanism. The winding mechanism is
disposed, for example, on a side of the backrest 4 or a side of the
bottom seat 3.
[0605] As shown in FIGS. 55, 58, and 59, the lumbar support plate
230 is lifted up by a control cable 271 and lowered by a control
cable 281. The control cable 271 includes an outer tube 272 and an
inner wire rod 273. The control cable 281 includes an outer tube
282 and an inner wire rod 283.
[0606] As shown in FIGS. 58 and 59, the outer tube 272 is routed
from above the pressure receiving member 41 to the front thereof.
The outer tube 272 has an end 272a directed downward. The end 172a
is fixed to the front surface of the lumbar support plate 230 above
the receiving recess 254 by an engagement piece 272b disposed at
the top end of the front surface of the pressure receiving member
41.
[0607] The inner wire rod 273 extends through the outer tube 272.
The inner wire rod 273 is drawn from the end 272a of the outer tube
272. The inner wire rod 273 has one end coupled to the top end of
the lumbar support plate 230. The coupling portion between the
inner wire rod 273 and the lumbar support plate 230 is below the
end 272a of the outer tube 272.
[0608] As shown in FIGS. 58 and 59, the outer tube 282 is routed
from above the pressure receiving member 41 to the rear thereof and
fixed to the rear surface of the pressure receiving member 41 by an
engagement piece 280 disposed on the rear surface of the pressure
receiving member 41. The outer tube 282 is folded back upward at
the engagement piece 280. The end 282a of the outer tube 282
penetrates through the surface below the receiving recess 254 and
is fixed to the front surface of the pressure receiving member 41
with the engagement piece 282b. The end 282a of the outer tube 282
is directed upward.
[0609] The inner wire rod 283 extends through the outer tube 282.
The inner wire rod 283 is drawn upward from the end 282a of the
outer tube 282 and has one end coupled to the top end of the lumbar
support plate 230. The coupling portion between the inner wire rod
283 and the lumbar support plate 230 is above the end 272a of the
outer tube 272.
[0610] The inner wire rods 273 and 283 have other ends drawn from
the other ends of the outer tubes 272 and 282, respectively. The
drawn portions are wound around, for example, a winding mechanism
(or an operating part for up-down movement). The inner wire rod 273
can be wound around the winding mechanism while the inner wire rod
283 can be unwound from the winding mechanism. The inner wire rod
273 can be unwound from the winding mechanism while the inner wire
rod 283 can be wound around the winding mechanism. The winding
mechanism is disposed, for example, on a side of the backrest 4 or
a side of the bottom seat 3.
[0611] The operation and use of the seat according to the eighth
embodiment will now be described.
[0612] The inner wire rod 263 wound around the winding mechanism
causes the inner wire rod 263 to be drawn into the outer tube 162.
This, in turn, causes the bottom end of the movable member 234 to
be pulled up by the inner wire rod 263 and move upward along the
front surface of the main body part 41a of the pressure receiving
member 41. As the bottom end of the movable member 234 moves up,
the movable member 234 gets erected relative to the front surface
of the main body part 41a. This causes the lumbar support plate 230
to be resiliently curved into a mountain shape. As the curvature of
the lumbar support plate 230 increases, the pressure area 237
travels frontward more away from the front surface of the pressure
receiving member 41. The pressure area 237 of the lumbar support
plate 230 presses aback receiving part 48a of the cushion pad 48
forward.
[0613] The inner wire rod 263 unwound from the winding mechanism
loosens the inner wire rod 263. Force to restore the lumbar support
plate 230 to an original shape reduces the height of mountain of
the lumbar support plate 230 to decrease the curvature of the
lumbar support plate 230. As the curvature decreases, the movable
member 234 is more inclined toward the front surface of the main
body part 41a, and the bottom end of the movable member 234 moves
downward along the front surface of the main body part 41a of the
pressure receiving member 41. The inner wire rod 263 is drawn from
the end 262a of the outer tube 262. The pressure area 237
approaches the front surface of the pressure receiving member 41
and the back receiving part 48a of the cushion pad 48 retreats
backward.
[0614] The inner wire rod 273 is wound around the winding mechanism
while the inner wire rod 273 is unwound from the winding mechanism
to loosen the inner wire rod 283. This, in turn, causes the top end
of the lumbar support plate 230 to be pulled up by the inner wire
rod 273 and move upward along the front surface of the main body
part 41a of the pressure receiving member 41. As the top end of the
lumbar support plate 230 moves upward, the bottom end of the
movable member 234 also moves upward along the front surface of the
main body part 41a of the pressure receiving member 41 and the
entire lumbar support plate 130 moves upward while retaining the
curvature thereof.
[0615] The inner wire rod 283 is wound around the winding mechanism
while the inner wire rod 273 is unwound from the winding mechanism
to loosen the inner wire rod 273. This, in turn, causes the top end
of the lumbar support plate 230 to be pulled down by the inner wire
rod 283 and move downward along the front surface of the main body
part 41a of the pressure receiving member 41. As the top end of the
lumbar support plate 230 moves downward, the bottom end of the
movable member 234 also moves downward along the front surface of
the main body part 41a of the pressure receiving member 41 and the
entire lumbar support plate 230 moves upwards while retaining the
curvature thereof.
[0616] In the seat described above, the adjustment of the curvature
and the vertical position of the lumbar support plate 230 can bring
the front surface of the backrest 4 into a close contact with the
back of the occupant in conformance with the shape thereof. This
improves seating comfort.
[0617] The lumbar support plate 230, which is assembled to the
pressure receiving member 41, moves together with the pressure
receiving member 41 in the front-back direction relative to the
backrest frame 40. Thus, the lumbar support plate 230 does not
prevent the backward movement of the occupant and can provide a
satisfactory cushioning performance.
[0618] The opening 231, formed on the front surface of the lumbar
support plate 230 at the horizontal center, makes a portion of the
cushion pad 48 in front of the opening 231 less compressed than
other portion of the cushion pad 48. This ensures a satisfactory
cushioning performance of a portion of the cushion pad 48 in
contact with the spine of the occupant and improves seating
comfort.
[0619] Since the lower portion of the lumbar support plate 230 is
divided, the movement of the hip or back of an occupant while the
bottom end of the movable member 234 is being fixed causes
deformation of the support member 235. This enhances the ability of
the lumbar support plate 230 to deform in conformity with caused by
changes in the posture of the occupant and thus improves the
seating comfort.
INDUSTRIAL APPLICABILITY
[0620] The present invention is applicable to a seat including a
pressure receiving member that is disposed inside a backrest and is
movable in the front-back direction.
REFERENCE NUMERALS
[0621] 1, 1A, 1B, 1C, 1D, 1E seat [0622] 4 backrest [0623] 40
backrest frame [0624] 40a upper frame segment [0625] 40b side frame
segment [0626] 40c lower frame segment [0627] 41 pressure receiving
member [0628] 41a main body part [0629] 41b extending part [0630]
41b1 front edge of extending part [0631] 41f claw (coupling portion
between wire rod and pressure receiving member) [0632] 48 cushion
pad [0633] 48a back receiving part [0634] 48b bank part [0635] 48e
slit [0636] 48g recess [0637] 48h step [0638] 49 skin [0639] 49a
pull strip (pulling member) [0640] 49b hook and loop fastener
[0641] 60 coupling wire (wire) [0642] 63 bent segment [0643] 71, 72
main body airbag [0644] 77L and 77R extending part airbag
* * * * *