U.S. patent application number 12/881288 was filed with the patent office on 2011-01-27 for passenger's weight measurement device for vehicle seat and attachment structure for load sensor.
This patent application is currently assigned to HONDA MOTOR CO., LTD.. Invention is credited to Shigeru ENDO, Takashi Furukawa, Mikihito Kojima, Naotaka Kumakiri, Harutomi Nishide, Kenji Sato, Tatsuya Yamazaki, Masashi Yoshifuku.
Application Number | 20110018302 12/881288 |
Document ID | / |
Family ID | 37854342 |
Filed Date | 2011-01-27 |
United States Patent
Application |
20110018302 |
Kind Code |
A1 |
ENDO; Shigeru ; et
al. |
January 27, 2011 |
PASSENGER'S WEIGHT MEASUREMENT DEVICE FOR VEHICLE SEAT AND
ATTACHMENT STRUCTURE FOR LOAD SENSOR
Abstract
A passenger's weight measurement device for a vehicle seat,
capable of suppressing generation of an initial load. The
passenger's weight measurement device includes a pair of slide
rails extending in parallel and fixed to the vehicle floor, and a
pair of side frames that support the seat and are disposed above
the pair of slide rails. Load cells are disposed between the pair
of the slide rails and the pair of the side frames. A set of first
connection frames for connecting both ends the pair of side frames
extend in parallel so as to be perpendicular to the pair of side
frames. Second and third connecting frames connect middle parts of
the pair of slide rails so as to be perpendicular to the slide
rails. The pair of the slide rails and the second and a third
connecting frames constitute an H-shaped frame.
Inventors: |
ENDO; Shigeru; (Shioya-gun,
JP) ; Sato; Kenji; (Shioya-gun, JP) ; Nishide;
Harutomi; (Wako-shi, JP) ; Yamazaki; Tatsuya;
(Wako-shi, JP) ; Kumakiri; Naotaka; (Wako-shi,
JP) ; Kojima; Mikihito; (Wako-shi, JP) ;
Yoshifuku; Masashi; (Wako-shi, JP) ; Furukawa;
Takashi; (Wako-shi, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 320850
ALEXANDRIA
VA
22320-4850
US
|
Assignee: |
HONDA MOTOR CO., LTD.
Tokyo
JP
TS TECH CO., LTD.
Asaka
JP
|
Family ID: |
37854342 |
Appl. No.: |
12/881288 |
Filed: |
September 14, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12289205 |
Oct 22, 2008 |
7823951 |
|
|
12881288 |
|
|
|
|
11518458 |
Sep 11, 2006 |
7455343 |
|
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12289205 |
|
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Current U.S.
Class: |
296/68.1 |
Current CPC
Class: |
B60N 2/002 20130101;
B60N 2/06 20130101; B60N 2/4263 20130101 |
Class at
Publication: |
296/68.1 |
International
Class: |
B60N 2/42 20060101
B60N002/42 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 12, 2005 |
JP |
2005-264002 |
Sep 12, 2005 |
JP |
2005-264128 |
Sep 15, 2005 |
JP |
2005-268465 |
Claims
1. (canceled)
2. A passenger's weight detecting device, comprising: a pair of
seat cushion side members comprising a pair of slide rails to be
arranged on a vehicle floor, and a pair of side frames for
supporting a seat, the pair of seat cushion side members being
provided on both sides of a seat cushion, respectively; and a load
sensor disposed between at least one of the slide rails and at
least one of the side frames; wherein the load sensor comprises a
rod portion that projects in at least one direction, wherein at
least one connecting member is provided between the pair of seat
cushion side members, wherein at least one hole into which the rod
portion is inserted is formed at least at one end portion of the
connecting member, and wherein the connecting member is provided
above the load sensor.
3. The passenger's weight detecting device as claimed in claim 2,
wherein the connecting member connects between front portions of
the pair of side frames.
4. The passenger's weight detecting device as claimed in claim 2,
wherein there are plural connecting members and the connecting
members connect between front portions of the pair of side frames
and between rear portions of the pair of side frames,
respectively.
5. The passenger's weight detecting device as claimed in claim 2,
wherein the rod portion projects upwardly from an upper surface of
the load sensor, and the rod portion is inserted into the hole
formed at the one end portion of the connecting member from under
the connecting member.
6. The passenger's weight detecting device as claimed in claim 2,
wherein the at least one hole is a plurality of holes into each of
which the rod portion of the load sensor is inserted, and wherein
the holes are formed at both end portions of the connecting member,
respectively.
7. The passenger's weight detecting device as claimed in claim 2,
wherein the hole formed at the one end portion of the connecting
member is longer in a front-and-rear direction than a hole formed
at a middle portion of the connecting member.
8. The passenger's weight detecting device as claimed in claim 2,
wherein an elastic member is provided between the hole into which
the rod portion of the load sensor is inserted and the rod
portion.
9. The passenger's weight detecting device as claimed in claim 8,
wherein enlarged-diameter portions are formed at both end portions
of the elastic member in a shaft line direction of the rod portion,
respectively, and the enlarged-diameter portions contact both
surfaces of the at least one hole.
10. The passenger's weight detecting device as claimed in claim 9,
wherein a collar member is provided between the elastic member and
the rod portion, and an inner surface of the elastic member
contacts an outer peripheral surface of the collar member.
11. The passenger's weight detecting device as claimed in claim 10,
wherein disk-shaped members are provided so as to press the
enlarged-diameter portions formed at the both end portions of the
elastic member to the hole from both sides, and each of the
disk-shaped members has a larger outer diameter than the
enlarged-diameter portions of the elastic member.
12. The passenger's weight detecting device as claimed in claim 2,
further comprising: a second connecting member for connecting
between the pair of seat cushion side members, the second
connecting member being provided so as to face to the connecting
member in an up-and-down direction.
13. The passenger's weight detecting device as claimed in claim 12,
wherein both end portions of at least one of the connecting member
and the second connecting member are connected with the pair of the
slide rails.
14. A passenger's weight detecting device, comprising: a pair of
seat cushion side members comprising a pair of slide rails to be
arranged on a vehicle floor, and a pair of side frames for
supporting a seat, the pair of seat cushion side members being
provided on both sides of a seat cushion, respectively; a pan frame
provided so as to cover at least front end portions of the pair of
side frames; a load sensor disposed between at least one of the
slide rails and at least one of the side frames; wherein the load
sensor comprises a rod portion that projects in at least one
direction, wherein at least one connecting member is provided
between the pair of seat cushion side members, wherein the
connecting member is provided between the pan frame and the load
sensor, and wherein at least one hole into which the rod portion is
inserted is formed at least at one end portion of the connecting
member.
15. The passenger's weight detecting device as claimed in claim 14,
wherein the connecting member connects between the pair of side
frames under the pan frame.
16. The passenger's weight detecting device as claimed in claim 14,
wherein there are plural connecting members and the connecting
members connect between front portions of the pair of side frames
and between rear portions of the pair of side frames,
respectively.
17. The passenger's weight detecting device as claimed in claim 14,
wherein the rod portion projects upwardly from an upper surface of
the load sensor, and the rod portion is inserted into the hole
formed at the one end portion of the connecting member from under
the connecting member.
18. The passenger's weight detecting device as claimed in claim 14,
wherein the holes into each of which the rod portion of the load
sensor is inserted are formed at both end portions of the
connecting member, respectively.
19. The passenger's weight detecting device as claimed in claim 14,
wherein the hole formed at the one end portion of the connecting
member is longer in a front-and-rear direction than a hole formed
at a middle portion of the connecting member.
20. The passenger's weight detecting device as claimed in claim 14,
wherein an elastic member is provided between the hole in which the
rod portion of the load sensor is inserted and the rod portion.
21. The passenger's weight detecting device as claimed in claim 20,
wherein enlarged-diameter portions are formed at both end portions
of the elastic member in a shaft line direction of the rod portion,
respectively, and the enlarged-diameter portions contact both
surfaces of the hole.
22. The passenger's weight detecting device as claimed in claim 21,
wherein a collar member is provided between the elastic member and
the rod portion, and an inner surface of the elastic member
contacts an outer peripheral surface of the collar member.
23. The passenger's weight detecting device as claimed in claim 22,
wherein disk-shaped members are provided so as to press the
enlarged-diameter portions formed at the both end portions of the
elastic member to the hole from both sides, and each of the
disk-shaped members has a larger outer diameter than the
enlarged-diameter portions of the elastic member.
24. The passenger's weight detecting device as claimed in claim 14,
further comprising: a second connecting member for connecting
between the pair of seat cushion side members, the second
connecting member is provided so as to face to the connecting
member in an up-and-down direction.
25. The passenger's weight detecting device as claimed in claim 24,
wherein both end portions of at least one of the connecting member
and the second connecting member are connected with the pair of the
slide rails.
26. A passenger's weight detecting device, comprising: a pair of
seat cushion side members comprising a pair of slide rails to be
arranged on a vehicle floor, and a pair of side frames for
supporting a seat, the pair of seat cushion side members being
provided on both sides of a seat cushion, respectively; and a load
sensor disposed between at least one of the slide rails and at
least one of the side frames; wherein the load sensor comprises a
rod portion that projects in at least one direction, a middle
portion connecting member is provided between middle portions of
the pair of slide rails, at least one end portion connecting member
provided between end portions in a front-and-rear direction of the
pair of side frames, and a hole into which the rod portion is
inserted is formed at least at one end portion of the end portion
connecting member.
27. The passenger's weight detecting device as claimed in claim 26,
wherein the end portion connecting member connects between the
front portions of the pair of side frames.
28. The passenger's weight detecting device as claimed in claim 26,
wherein there are plural end portion connecting members and the end
portion connecting members connect between the front portions of
the pair of side frames and between the rear portions of the pair
of side frames, respectively.
29. The passenger's weight detecting device as claimed in claim 26,
wherein the rod portion projects upwardly from an upper surface of
the load sensor, and the rod portion is inserted into the hole
formed at the one end portion of the end portion connecting member
from under the end portion connecting member.
30. The passenger's weight detecting device as claimed in claim 26,
wherein the holes into each of which the rod portion of the load
sensor is inserted are formed at both end portions of the end
portion connecting member, respectively.
31. The passenger's weight detecting device as claimed in claim 26,
wherein the hole formed at the one end portion of the end portion
connecting member is longer in a front-and-rear direction than a
hole formed at a middle portion of the end portion connecting
member.
32. The passenger's weight detecting device as claimed in claim 26,
wherein an elastic member is provided between the hole in which the
rod portion of the load sensor is inserted and the rod portion.
33. The passenger's weight detecting device as claimed in claim 32,
wherein enlarged-diameter portions are formed at both end portions
of the elastic member in a shaft line direction of the rod portion,
respectively, and the enlarged-diameter portions contact with both
surfaces of the hole.
34. The passenger's weight detecting device as claimed in claim 33,
wherein a collar member is provided between the elastic member and
the rod portion, and an inner surface of the elastic member
contacts an outer peripheral surface of the collar member.
35. The passenger's weight detecting device as claimed in claim 34,
wherein disk-shaped members are provided so as to press the
enlarged-diameter portions formed at the both end portions of the
elastic member to the hole from both sides, and each of the
disk-shaped members has a larger outer diameter than the
enlarged-diameter portions of the elastic member.
36. The passenger's weight detecting device as claimed in claim 26,
further comprising: a third connecting member for connecting
between the pair of seat cushion side members, the third connecting
member being provided so as to face to at least one connecting
member of the middle portion connecting member and the end portion
connecting member in an up-and-down direction.
37. The passenger's weight detecting device as claimed in claim 36,
wherein both end portions of at least one of the one connecting
member and the third connecting member are connected with the pair
of the slide rails.
38. The passenger's weight detecting device as claimed in claim 26,
further comprising: a third connecting member for connecting
between the pair of seat cushion side members, the third connecting
member is provided so as to face to the middle portion connecting
member in an up-and-down direction.
39. The passenger's weight detecting device as claimed in claim 13,
wherein the second connecting member is provided more forwardly
than rear portions of the pair of side frames.
40. The passenger's weight detecting device as claimed in claim 25,
wherein the second connecting member is provided more forwardly
than rear portions of the pair of side frames.
41. The passenger's weight detecting device as claimed in claim 37,
wherein the third connecting member is provided more forwardly than
the rear portions of the pair of side frames.
42. A passenger's weight detecting device, comprising: a pair of
seat cushion side members comprising a pair of slide rails to be
arranged on a vehicle floor, and a pair of side frames for
supporting a seat, the pair of seat cushion side members being
provided on both sides of a seat cushion, respectively; and a load
sensor disposed between at least one of the slide rails and at
least one of the side frames; wherein the load sensor comprises a
rod portion which projects in at least one direction, at least one
connecting member provided between the pair of seat cushion side
members, at least one hole into which the rod portion is inserted
is formed at least at one end portion of the connecting member, and
an elastic member is provided between the hole in which the rod
portion of the load sensor is inserted and the rod portion.
43. The passenger's weight detecting device as claimed in claim 42,
wherein the rod portion projects upwardly from an upper surface of
the load sensor, and the rod portion is inserted into the hole
formed at the one end portion of the connecting member from under
the connecting member.
44. The passenger's weight detecting device as claimed in claim 42,
wherein there are a plurality of holes into each of which the rod
portion of the load sensor is inserted are formed at both end
portions of the connecting member, respectively.
45. The passenger's weight detecting device as claimed in claim 42,
wherein the hole formed at the one end portion of the connecting
member is longer in a front-and-rear direction than a hole formed
at a middle portion of the connecting member.
46. The passenger's weight detecting device as claimed in claim 42,
wherein enlarged-diameter portions are formed at both end portions
of the elastic member in a shaft line direction of the rod portion,
respectively, and the enlarged-diameter portions contact both
surfaces of the hole.
47. The passenger's weight detecting device as claimed in claim 46,
wherein a collar member is provided between the elastic member and
the rod portion, and an inner surface of the elastic member
contacts an outer peripheral surface of the collar member.
48. The passenger's weight detecting device as claimed in claim 47,
wherein disk-shaped members are provided so as to press the
enlarged-diameter portions formed at the both end portions of the
elastic member to the hole from both sides, and each of the
disk-shaped members has a larger outer diameter than the
enlarged-diameter portions of the elastic member.
49. The passenger's weight detecting device as claimed in claim 42,
further comprising: a second connecting member for connecting
between the pair of seat cushion side members, the second
connecting member being provided so as to face to the connecting
member in an up-and-down direction.
50. The passenger's weight detecting device as claimed in claim 49,
wherein both end portions of at least one of the connecting member
and the second connecting member are connected with the pair of the
slide rails.
51. The passenger's weight detecting device as claimed in claim 12,
wherein the connecting member and the second connecting member are
provided so as to be parallel to each other.
52. The passenger's weight detecting device as claimed in claim 24,
wherein the connecting member and the second connecting member are
provided so as to be parallel to each other.
53. The passenger's weight detecting device as claimed in claim 36,
wherein the connecting member and the second connecting member are
provided so as to be parallel to each other.
54. The passenger's weight detecting device as claimed in claim 48,
wherein the connecting member and the second connecting member are
provided so as to be parallel to each other.
55. The passenger's weight measurement device as claimed in claim
14, wherein the rod portion projects upwardly from an upper surface
of the load sensor, and the rod portion is inserted into the hole
formed at the one end portion of the connecting member from under
the connecting member, wherein the holes into each of which the rod
portion of the load sensor is inserted are formed at both end
portions of the connecting member, respectively, wherein an elastic
member is provided between the hole in which the rod portion of the
load sensor is inserted and the rod portion, wherein
enlarged-diameter portions are formed at both end portions of the
elastic member in a shaft line direction of the rod portion,
respectively, and the enlarged-diameter portions contact both
surfaces of the hole, and wherein a collar member is provided
between the elastic member and the rod portion, and an inner
surface of the elastic member contacts an outer peripheral surface
of the collar member.
Description
[0001] This is a Continuation of U.S. application Ser. No.
12/289,205 filed Oct. 22, 2008, which is a Division of U.S.
application Ser. No. 11/518,458 filed Sep. 11, 2006, which claims
priority to Japanese Patent Application No. 2005-264128 filed on
Sep. 12, 2005, Japanese Application No. 2005-268465 filed on Sep.
15, 2005 and Japanese Application No. 2005-264002 filed on Sep. 12,
2005, the entire disclosures of which are herein incorporated by
reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a passenger's weight
measurement device for vehicle seat, for measuring a weight of a
passenger of a vehicle seat, and an attachment structure for
attaching a load sensor to the passenger's weight measurement
device.
[0004] 2. Description of the Related Art
[0005] Recently, to improve performance of various safety devices
such as a seat belt and an air bag, operations of the safety
devices have been controlled in accordance with a weight of a
passenger sitting on a vehicle seat in some cases. In the
conventional passenger's weight measurement device for measuring a
weight of a sitting passenger, a load sensor is disposed between a
vehicle floor and the vehicle seat (For example, refer to JP A
2004-317285 and U.S. Pat. No. 6,161,891).
[0006] However, when the passenger's weight measurement device is
assembled, when the vehicle seat is fixed to the passenger's weight
measurement device, and when the passenger's weight measurement
device is fixed to the vehicle floor or the like, a dimension error
or an assembling position error occurs to cause very low
distortion. Because an initial load is applied to the load sensor
by the distortion, there is a first problem that it is difficult to
accurately measure the passenger's weight.
[0007] JP A 11-304579 discloses a passenger's weight measurement
device capable of simplifying characteristics of a load applied on
a load sensor as much as possible.
[0008] The passenger's weight measurement device disclosed in JP A
11-304579 is equipped with a seat connection mechanism which
includes an arm disposed to interconnect a seat bracket and a seat
of a vehicle and to rotate up and down. The device also includes a
load sensor disposed between the vehicle and the seat to detect a
seat weight. The arm is pivotally attached to a pivotal shaft
(pivot) of the seat side and a pivot of a car body side, and the
load sensor selectively receives an up-and-down direction component
of the seat weight applied on the arm. According to the passenger's
weight measurement device disclosed in JP A 11-304579, displacement
of the seat with respect to the vehicle body, which is caused when
a load is applied on the seat, has certain regularity, and
characteristics of the load applied on the load sensor are
simplified, thereby facilitating capturing of the passenger's
weight on the seat.
[0009] According to the passenger's weight measurement device
disclosed in JP A 11-304579, seat adjusters project from four
positions, front, back, left and right, of a bottom surface of a
seat cushion on which the passenger sits. The seat adjuster is a
portion of which a seat frame partially projects, and can slide
back and forth on a pair of seat rails by passenger's adjustment.
The seat adjuster and the seat rails constitute a so-called slide
rail. However, the passenger's weight measurement device disclosed
in JP A 11-304579 has a problem that the large number of components
such as a linking member is increased because the pair of slide
rails and the seat bracket fixed to the vehicle body floor side are
linked together by a parallelogram linking mechanism. Because the
parallelogram linking mechanism is disposed between the pair of
slide rails and the seat bracket, there is a problem that it is
difficult to set a height from the vehicle body floor to an upper
surface of the seat cushion equal to or less than a certain
height.
[0010] To solve the aforementioned problems, a plurality of
compression type load cells (load sensors) are disposed between the
pair of slide rails arranged on the vehicle body floor side and the
pair of side frames for supporting the seat. Thus, the
configuration is simplified and the restrictions on the height from
the vehicle body floor to the upper surface of the seat cushion are
eliminated. However, generally it is difficult to accurately fix
the pair of slide rails and the like to the vehicle body floor
side. Further, it is difficult to maintain a facing distance
between the pair of side frames because of the seat sliding. In
this structure, there is a second problem that an unnecessary force
is applied on the load cell to interfere with passenger's load
measurement.
SUMMARY OF THE INVENTION
[0011] In connection with the first problem, it is an object of the
present invention to provide a passenger's weight measurement
device for a vehicle seat, and an attachment structure for a load
sensor, capable of suppressing generation of an initial load.
[0012] In connection with the second problem, it is another object
of the present invention to provide a passenger's weight
measurement device which includes a pair of slide rails and load
cells arranged at four corners of the slidable seat and which can
prevent interference with load measurement of the load cells.
[0013] In accordance with a first aspect of the present invention,
a passenger's weight measurement device for a vehicle seat
comprises an upper rail disposed to be movable back and forth on a
lower rail fixed to a vehicle floor; a load sensor fixed on the
upper rail; and a frame disposed on the load sensor and below a
vehicle seat, wherein a rod extends from the load sensor to
penetrate the frame and to be inserted into an insertion hole
formed in a center of a leaf spring, the leaf spring is curved into
an angle shape to separate the center of the leaf spring from the
frame, a nut is engaged with the rod on the leaf spring, and both
hems of the leaf spring abut on the frame in a state that the leaf
spring is fastened by the nut.
[0014] In accordance with a second aspect of the present invention,
in an attachment structure for attaching a load sensor to a frame
disposed below a vehicle seat, a rod extends from the load sensor
to penetrate the frame and to be inserted into an insertion hole
formed in a center of a leaf spring, the leaf spring is curved into
an angle shape to separate the center of the leaf spring from the
frame, a nut is engaged with the rod on the leaf spring, and both
hems of the leaf spring abut on the frame in a state that the leaf
spring is fastened by the nut.
[0015] In accordance with the first and second aspects, preferably,
a collar through which the rod is inserted penetrates the frame,
the leaf spring is held between the collar and the nut, and the
leaf spring and the collar are held between the nut and the load
sensor.
[0016] In accordance with the first and second aspect, preferably,
the rod is inserted into the insertion hole in a position shifted
from a line segment for interconnecting the both hems of the leaf
spring when seen towards an inserting direction of the rod.
[0017] In accordance with the first and second aspects, preferably,
holes are formed in the both hems of the leaf spring, and a part of
a cover covering the both hems of the leaf spring is inserted into
the holes.
[0018] According to the first and second aspects, because the leaf
spring is curved into an angle shape to separate the center of the
leaf spring from the frame, and the nut is engaged with the rod
from above the leaf spring, the frame is shifted in a vertical
direction with respect to the load sensor. The fastening of the nut
elastically deforms the leaf spring.
[0019] According to the first and second aspects of the present
invention, the frame is shifted in the vertical direction with
respect to the load sensor. Thus, even when the left and right
lower rails, the left and right upper rails, the frame, or the like
is distorted during assembling, it is possible to avoid applying an
initial load generated by the distortion on the load sensor.
[0020] Because both hems of the leaf spring are in contact with the
frame by fastening the nut, the load sensor is not loosened with
respect to the frame. Thus, it is possible to suppress a reduction
in rigidity.
[0021] Because the elastic deformation of the leaf spring by the
nut applies a load on the nut from the leaf spring, it is possible
to prevent loosening of the nut.
[0022] In accordance with a third aspect of the present invention,
a passenger's weight measurement device for a vehicle seat
comprises a pair of left and right upper rails disposed to be
movable back and forth on a pair of left and right lower rails
fixed to a vehicle floor; four load sensors fixed on front and rear
sides of the pair of upper rails; and a frame disposed on the four
load sensors and below the vehicle seat, wherein two of the four
load sensors, which are arranged on one diagonal line, are set to
play in back-and-forth and left-and-right directions with respect
to the frame, and the other two load sensors arranged on the other
diagonal line are fixed in back-and-forth and left-and-right
directions with respect to the frame.
[0023] According to the third aspect of the present invention,
because the two load sensors located on one diagonal line are set
to play back and forth and left and right with respect to the
frame, even when distortion occurs in the upper rail or the lower
rail, the load sensors located on one diagonal line are
horizontally shifted with respect to the frame. Thus, no initial
load generated by distortion is applied on the load sensors.
[0024] In accordance with a fourth aspect of the present invention,
a passenger's weight measurement device for a vehicle seat employs
a structure in which a pair of side frames supporting the seat is
structured to be rigid, a pair of load cells located on one
diagonal line among four load cells disposed between the seat and a
vehicle floor are moveable up and down, and a pair of load cells
located on the other diagonal line are moveable up and down and
play.
[0025] More specifically, in accordance with the fourth aspect of
the present invention, a passenger's weight measurement device for
a vehicle seat comprises a pair of slide rails arranged in a
vehicle floor; a pair of side frames for supporting the seat; and
load cells disposed at four corners of the pair of slide rails and
the pair of side frames, wherein the pair of side frames constitute
a rectangular seat frame with a set of first connection frames for
connecting both ends the pair of side frames extending in parallel
so as to be perpendicular to the pair of side frames.
[0026] According to the fourth aspect, the pair of side frames
constitute a rectangular seat frame with a set of first connection
frames for connecting both ends the pair of side frames extending
in parallel so as to be perpendicular to the pair of side frames.
Thus, the pair of side rails and the set of first connection frames
are connected together, thereby providing a highly rigid
rectangular seat frame.
[0027] The high rigidity of the seat frame may mean that distortion
of the seat frame with respect to a force applied on the seat frame
is small, for example, displacement of the pair of side rails may
be small with respect to a force (compression stress) applied in a
mutually approaching direction of the pair of side rails, or
displacement of the pair of side rails may be small with respect to
a force (tension stress) applied in a mutually separating direction
of the pair of side rails. According to the fourth aspect of the
present invention, it is prevented that an unnecessary force is
applied on the load cell when the pair of side frames slide
together with the load cell on the slide rail. Then, it is possible
to accurately measure passenger's load.
[0028] In accordance with the fourth aspect, preferably, in the
pair of slide rails, a pair of first slide rails and a pair of
second slide rails are connected so as to be slidable,
respectively, the pair of first slide rails extend in parallel to
be fixed to the vehicle floor side, and the pair of first slide
rails comprise a second connection frame for connecting middle
parts of the pair of first slide rails so as to be perpendicular to
the first slide rails.
[0029] In this case, the pair of first slide rails and the second
connection frame are connected together to provide a highly rigid
H-shaped frame (H-frame). The high rigidity of the H-frame may mean
that distortion of the H-frame with respect to a force applied on
the H-frame is small, for example, displacement of the pair of
first side rails may be small with respect to a force (compression
stress) applied in a mutually approaching direction of the pair of
first side rails, or displacement of the pair of first side rails
may be small with respect to a force (tension stress) applied in a
mutually separating direction of the pair of first side rails.
According to the fourth aspect of the present invention, it is
prevented that an unnecessary force is applied on the load cell.
Then, it is possible to accurately measure passenger's load.
[0030] In accordance with the fourth aspect, preferably, the four
load cells are arranged at four corners of the pair of second slide
rails, and the pair of second slide rails extend in parallel, and
comprises a third connection frame for connecting middle parts of
the pair of second slide rails so as to be perpendicular to the
second slide rails.
[0031] In this case, the pair of second slide rails and the third
connection frame are connected together to provide a highly rigid
H-frame. The high rigidity of the H-frame may mean that distortion
of the H-frame with respect to a force applied on the H-frame is
small, for example, displacement of the pair of second side rails
may be small with respect to a force (compression stress) applied
in a mutually approaching direction of the pair of second side
rails, or displacement of the pair of second side rails may be
small with respect to a force (tension stress) applied in a
mutually separating direction of the pair of second side rails.
According to the fourth aspect of the present invention, it is
prevented that an unnecessary force is applied on the load cell.
Then, it is possible to accurately measure passenger's load.
[0032] In accordance with the fourth aspect, preferably, a pair of
load cells located on one diagonal line among the four load cells
are connected to be movable up and down with respect to the seat
frame, and a pair of load cells located on the other diagonal line
are connected to be movable up and down and play with respect to
the seat frame.
[0033] In this case, it is possible to absorb manufacturing errors
of the pair of slide rails, the four load cells, and the pair of
side frames, and height-direction accumulated errors of these
components. It is also possible to absorb assembling errors of the
pair of slide rails, the four load cells, and the pair of seat
frames.
[0034] In accordance with the fourth aspect, preferably, in the set
of first connection frames, one of the first connection frames is
connected to ends of the pair of side rails so as to be easily
deformed by shock having a predetermined or more strength.
[0035] For example, in the pair of side frames, a pair of tongue
pieces extend in one ends, and one of the first connection frames
is connected to tips of the pair of tongue pieces. Constrictions
are disposed in base ends of the pair of tongue pieces, and shock
stress concentrates on these constrictions. According to the fourth
aspect of the present invention, by employing a structure easily
deformed by shock having a predetermined or more strength, it is
possible to protect the load cells from shock having a
predetermined or more strength.
[0036] In accordance with the fourth aspect, preferably, the load
cell comprises a male screw in one end and a flange in the other
end located to face opposite to the one end, in the seat frame,
four holes are formed to insert the male screws corresponding to an
arrangement of the four load cells, the pair of second slide rails
are fixed to the flanges, first elastic bushings are inserted into
a pair of first holes located on one diagonal line among the four
holes, a first collar is elastically disposed between the first
elastic bushing and the male screw, a plain washer and a conical
spring washer are mounted on the first collar, and a nut is
fastened to the male screw, in a region of the seat frame, which is
engaged with the pair of male screws located on the one diagonal
line, an up-and-down moving amount is regulated by a length of the
first collar in an axial direction, and the conical spring washer
presses the seat frame to the load cell side.
[0037] In this case, it is possible to realize a connection
structure movable up and down by general mechanical elements. It is
also possible to absorb manufacturing errors of the pair of slide
rails, the four load cells and the seat frames, and
height-direction accumulated errors of these components.
[0038] In accordance with the fourth aspect, preferably, second
elastic bushings are inserted into a pair of second holes located
on the other diagonal line among the four holes, a second collar is
inserted after a plain washer is inserted into the male screw, the
second elastic bushing is disposed to play in the second collar, a
conical spring washer are mounted on the second collar, and a nut
is fastened to the male screw, in a region of the seat frame, which
is engaged with the pair of male screws located on the other
diagonal line, an up-and-down moving amount is regulated by a
length of the second collar in an axial direction, and the conical
spring washer presses the seat frame to the load cell side.
[0039] In this case, it is possible to realize a connection
structure permitted to move up and down and to play by general
mechanical elements. It is also possible to absorb manufacturing
errors of the pair of slide rails, the four load cells and the seat
frames, and height-direction accumulated errors of these
components.
[0040] In accordance with the fourth aspect, preferably, an inner
diameter of the first elastic bushing is formed in a conical body,
and an inner periphery of an upper bottom surface of the conical
body having a small radius abuts on an outer periphery of the first
collar.
[0041] In this case, it is possible to realize both of facilitation
of assembling and absorption of assembling errors by forming the
inner diameter of the first elastic bushing in the conical
body.
[0042] According to the fourth aspect of the present invention, the
pair of side frames supporting the seat and a set of first
connection frames are connected together to provide a highly rigid
rectangular seat frame. The pair of slide rails and the second and
third connection frames are connected together to provide a highly
rigid H-frame. For example, it is possible to prevent tilting of
the load cell by moving the pair of side frames in a mutually
separating direction. According to the fourth aspect of the present
invention, it is possible to provide a passenger's weight
measurement device for a vehicle seat, capable of preventing
interference with load cell load measurement without increasing the
number of components and without greatly changing the framework of
the conventional seat structure.
[0043] Furthermore, according to the fourth aspect of the present
invention, it is possible to absorb manufacturing errors of the
pair of slide rails, the four load cells and the seat frames, and
height-direction accumulated errors of these components. It is also
possible to absorb horizontal accumulated errors of the components
caused by assembling.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] The present invention will become more fully understood from
the detailed description given hereinafter and the accompanying
drawing given by way of illustration only, and thus are not
intended as a definition of the limits of the present invention,
and wherein:
[0045] FIG. 1 is a perspective diagram showing a passenger's weight
measurement device for a vehicle seat.
[0046] FIG. 2 is an exploded perspective diagram showing the
passenger's weight measurement device.
[0047] FIG. 3 is a perspective diagram showing a load sensor.
[0048] FIG. 4 is a plan diagram showing a rectangular frame.
[0049] FIG. 5 is a plan diagram showing a right front section of
the rectangular frame.
[0050] FIG. 6 is a schematic sectional diagram cut along the line
VI-VI of FIG. 5.
[0051] FIG. 7 is a schematic sectional diagram cut along the line
VII-VII of FIG. 5.
[0052] FIG. 8 is a plan diagram showing a right rear section of the
rectangular frame.
[0053] FIG. 9 is a schematic sectional diagram cut along the line
IX-IX of FIG. 8.
[0054] FIG. 10 is a schematic sectional diagram cut along the line
X-X of FIG. 8.
[0055] FIG. 11 is an exploded perspective assembly diagram showing
a passenger's weight measurement device according to a second
embodiment.
[0056] FIG. 12 is an exploded perspective diagram showing a seat
section including the passenger's weight measurement device of the
second embodiment.
[0057] FIG. 13 is a perspective appearance diagram showing the
passenger's weight measurement device of the second embodiment.
[0058] FIG. 14 is a perspective appearance diagram showing a
schematic configuration of the passenger's weight measurement
device of the second embodiment.
[0059] FIG. 15 is a perspective appearance diagram showing the
passenger's weight measurement device of the second embodiment.
[0060] FIG. 16 is an enlarged longitudinal sectional diagram of a
main section of FIG. 15.
[0061] FIG. 17 is an enlarged plan diagram of a main section of
FIG. 16.
[0062] FIG. 18 is a longitudinal sectional diagram showing the
first elastic bushing applied to the passenger's weight measurement
device of the second embodiment.
[0063] FIG. 19 is a longitudinal sectional diagram of a load cell
located on one diagonal line in the passenger's weight measurement
device of the second embodiment.
[0064] FIG. 20 is a longitudinal sectional diagram of a load cell
located on the other diagonal line in the passenger's weight
measurement device of the second embodiment.
PREFERRED EMBODIMENT OF THE INVENTION
[0065] The preferred embodiments of the present invention will be
described below with reference to the accompanying drawings. In the
embodiments described below, various preferable technical
limitations are described to carry out the invention, but the scope
of the invention is not limited to the embodiment and the examples
shown in the figures.
First Embodiment
[0066] FIG. 1 is a perspective diagram of a passenger's weight
measurement device 1 for a vehicle seat, and FIG. 2 is an exploded
perspective diagram of the passenger's weight measurement device
1.
[0067] As shown in FIGS. 1 and 2, a slide adjuster 2 for adjusting
a back-and-forth position of the vehicle seat is mounted to a floor
of a passenger's room. The slide adjuster 2 includes lower rails 3
and 4 disposed in parallel with each other, an upper rail 5 engaged
with the lower rail 3 to slide back and forth on the lower rail 3
with respect to the same, an upper rail 6 engaged with the lower
rail 4 to slide back and forth on the lower rail 3 with respect to
the lower rail 4, a lower bracket 7 fixed to bottom surfaces of the
lower rails 3 and 4 by bolts and nuts or rivets to bridge a gap
therebetween, a lock mechanism 8 for locking/unlocking the upper
rails 5 and 6 to/from the lower rails 3 and 4, brackets 31 and 33
fixed to the bottom surface of the lower rail 3, and brackets 32
and 34 fixed to the bottom surface of the lower rail 4. The
brackets 31 to 34 are mounted to the vehicle floor, and the lower
rails 3 and 4 are fixed to the vehicle floor.
[0068] A bracket 11 is fixed to a back-and-forth direction center
of an upper surface of the right upper rail 5 by bolts and nuts or
rivets, and a bracket 12 is fixed to a back-and-forth direction
center of an upper surface of the left upper rail 6 by bolts and
nuts or rivets. Both brackets 11 and 12 are disposed to be upright
on the upper surfaces of the upper rails 5 and 6. A right end of a
submarine pipe 10 is welded to the bracket 11, and a left end of
the submarine pipe 10 is welded to the bracket 12, thereby
installing the submarine pipe 10 between the brackets 11 and
12.
[0069] A load sensor 21 is mounted on a front end of the upper
surface of the right upper rail 5, and a load sensor 23 is mounted
on a rear end of the upper surface of the right upper rail 5.
Similarly, a load sensor 22 is mounted on a front end of the upper
surface of the left upper rail 6, and a load sensor 24 is mounted
on its rear end. Seen from the above, the load sensors 21 to 24 are
arranged to be apexes of a square or a rectangle.
[0070] FIG. 3 is a perspective diagram of the load sensor 21. As
shown in FIG. 3, the load sensor 21 includes a columnar sensing
section 21a for detecting a load, a platelike flange section 21b
extending laterally back and forth from a lower end of the sensing
section 21a, a rod 21c extending from an upper end of the sensing
section 21a upward, and a connector 21d extending from the sensing
section 21a to be parallel to the flange section 21b. The rod 21c
is formed into a male screw shape. Female screw-shaped circular
holes 21e and 21f put-through up and down are formed in front and
rear parts of the flange section 21b. The sensing section 21a
incorporates a strain gauge for converting a load into an electric
signal.
[0071] As shown in FIG. 2, the load sensor 21 is secured to the
right upper rail 5. Specifically, a bottom surface of the flange
section 21b abuts on the upper surface of the upper rail 5, and
bolts 35 and 36 penetrating the upper rail 5 up and down are
engaged with the circular holes 21e and 21f to fix the load sensor
21. The load sensor 21 may be fixed to the upper rail 5 by
fastening nuts around the bolts 35 and 36 on the flange section 21b
without forming any screw threads in the circular holes 21e and
21f.
[0072] The load sensors 22 to 24 are all configured as in the case
of the load sensor 21. Thus, the load sensors 22 to 24 will be
described by using reference numerals of sensing section 22a to
24a, flange sections 22b to 24b, rods 22c to 24c, and connector 22d
to 24d.
[0073] As in the case of the load sensor 21, the load sensor 23 is
fixed to the upper surface of the right upper rail 5 by a bolt 37,
and the load sensors 22 and 24 are fixed to the upper surface of
the left upper rail 6 by bolts 38 and 39.
[0074] In the fixed state of the load sensors 21 to 24, the
connectors 23d and 24d are directed forward for the rear load
sensors 23 and 24, and the connectors 21d and 22d are directed
backward for the front load sensors 21 and 22.
[0075] As shown in FIGS. 1 and 2, rectangular frames 40 are mounted
on the load sensors 21 to 24. FIG. 4 is a top diagram of the
rectangular frame 40. As shown in FIG. 4, the rectangular frame 40
includes a right beam 41, a left beam 42, a front member 43, and a
rear cross pipe 44.
[0076] The right beam 41 is a metal material having a web 41a and
right and left flanges 41b and 41c and U-shaped in section. A
length in front-and-rear direction of the web 41a is longer than
those of the flanges 41b and 41c, and a front end 41d of the web
41a extends before front ends of the flanges 41b and 41c. A
rectangular notch 41e is formed in a side edge of the front end 41d
of the web 41a, and a width of this part is narrower than those of
other parts. A mounting hole 41f is formed in a front of the web
41a, and a mounting hole 41g is formed in a rear part of the web
41a. The mounting hole 41f is located behind the notch 41e. A
diameter of the rear mounting hole 41g is larger than that of the
front mounting hole 41f.
[0077] Similarly, the left beam 42 is a metal material having a web
42a and left and right flanges 42b and 42c and U-shaped in section,
and a notch 42e is formed in a side edge of a front end 42d of the
web 42a. Mounting holes 42f and 42g are formed in the web 42a,
back-and-forth positions of the mounting holes 42f and 41f are
almost aligned with each other, back-and-forth positions of the
mounting holes 42g and 41g are almost aligned with each other, and
the attaching hole 42f is located behind the notch 42e. In the left
beam 42, a diameter of the front mounting hole 42f is larger than
that of the rear mounting hole 42g.
[0078] The front member 43 is a metal member having a web and a
flange and U-shaped in section. A right end of the front member 43
is welded to the front end 41d of the web 41a on a front side of
the notch 41e of the beam 41, and a left end of the front member 43
is welded to the front end 42d of the web 42a on a front side of
the notch 42e of the beam 42.
[0079] The cross pipe 44 is installed between the rear ends of the
beams 41 and 42 to be welded to the same. As in the case of the
front notches 41e and 42e, a notch may be formed in the beam 41
between the cross pipe 44 and the load sensor 23, or in the beam 42
between the cross pipe 44 and the load sensor 24.
[0080] Referring to FIGS. 5 to 7, a structure for mounting the
right front load sensor 21 to the rectangular frame 40 will be
described. FIG. 5 is a plan diagram of a right front part of the
rectangular frame 40, FIG. 6 is a schematic sectional diagram cut
along the line VI-VI, and FIG. 7 is a schematic sectional diagram
cut along the line VII-VII. As shown in FIGS. 5 to 7, a ring-shaped
NYLON bushing 61 is fitted in an edge of the right front mounting
hole 41f, and grease is applied on the NYLON bushing 61. A stepped
collar 62 constituted of a cylindrical part 62a and a ring
platelike flange part 62b formed in one end surface of the
cylindrical part 62a is inserted into the mounting hole 41f inside
the NYLON bushing 61. In this case, the cylindrical part 62a
penetrates the web 41a from bottom up, and the flange part 62b
engages the bottom surface of the web 41a, thereby preventing
pulling-out of the stepped collar 62 upward. The cylindrical part
62a projects more than the upper surface of the web 41a, and an
upper end surface of the cylindrical part 62a is located higher
than the upper surface of the web 41a. The cylindrical part 62a is
fitted to the NYLON bushing 61 to leave no space between the
cylindrical part 62a and the NYLON bushing 61.
[0081] The rod 21c of the load sensor 21 is inserted into the
stepped collar 62, and this rod 21c penetrates the web 41a from
bottom up. An inner diameter of the stepped collar 62 is designed
to be slightly larger than a diameter of the rod 21c. By such
designing, a dimension error and a mounting position error are
prevented. Accordingly, even when the diameter of the rod 21c is
smaller than the inner diameter of the stepped collar 62, the rod
21c is fixed to the beam 41 with substantially no play in
back-and-forth and left-and-right directions.
[0082] A nut 66 is engaged with the rod 21c, a plain washer 63 and
a leaf spring 64 are disposed between the upper surface of the web
41a of the beam 41 and the nut 66, and the nut 66 is engaged with
the leaf spring 64. The rod 21c is inserted into the plain washer
63, and the plain washer 63 is mounted on an end surface of the
stepped collar 62. The plain washer 63 is located apart from the
upper surface of the web 41a of the beam 41.
[0083] The leaf spring 64 is formed into an isosceles triangular
shape, an insertion hole is formed in its center (center of gravity
of the isosceles triangle), and the rod 21c is inserted into this
insertion hole. Corners of the leaf spring 64 equal to each other
are covered with covers 65, and grease is applied on the covers 65.
The cover 65 is formed by molding and hardening a fluid resin at
the corner of the leaf spring 64, and a part of the cover 65 is
inserted into a hole 64a formed at the corner of the leaf spring
64. Seen from the side, the leaf spring 64 is curved so that a
center of the leaf spring 64 can be angled, and the corner covered
with the cover 65 is hemmed. By fastening the nut 66, the plain
washer 63 and the leaf spring 64 are held between the nut 66 and
the upper end surface of the cylindrical part 62a, and the leaf
spring 64, the plain washer 63 and the stepped collar 62a are held
between the nut 66 and the load sensor 21. By fastening the nut 66,
the covers 65 of both hems of the leaf spring 64 abut on the upper
surface of the web 41a of the beam 41 to press the leaf spring 64
to the web 41a. The insertion hole into which the rod 21c has been
inserted is formed in the center-of-gravity part of the leaf spring
64. Accordingly, seen from the insertion direction of the rod 21c,
the rod 21c is inserted into the insertion hole in a position
shifted from a line for interconnecting both corners of the leaf
spring which becomes a contact between the leaf spring 64 and the
web 41a.
[0084] Since the fastening of the nut 66 causes elastic deformation
of the leaf spring 64, a load is applied on the nut 66 to prevent
its loosening. As the rod 21c is inserted into the stepped collar
62, even when the nut 66 is excessively fastened, it is possible to
prevent bonding of the entire leaf spring 64 to the upper surface
of the web 41a caused by flat deformation of the leaf spring
64.
[0085] A position of the mounting hole 41f in a width direction of
the web 41a is slightly right from a center, and both hems of the
leaf spring 64 are in contact with a width-direction center of the
web 41a.
[0086] Referring to FIGS. 8 to 10, a structure for mounting the
right rear load sensor 23 to the rectangular frame 40 will be
described. FIG. 8 is a plan diagram of a right rear part of the
rectangular frame 40, FIG. 9 is a schematic sectional diagram cut
along the line IX-IX, and FIG. 10 is a schematic sectional diagram
cut along the line X-X.
[0087] As shown in FIGS. 8 to 10, a ring-shaped NYLON bushing 71 is
fitted in an edge of the right rear mounting hole 41g, and grease
is applied on the NYLON bushing 71. The rod 23c of the load sensor
23 is inserted into a plain washer 73, and inserted into the
mounting hole 41g to penetrate the web 41a from bottom up. The
plain washer 73 is held between the web 41a of the beam 41 and the
sensor part 23a.
[0088] The rod 23c is inserted into the cylindrical part 72a of a
stepped collar 72, the cylindrical part 72a penetrates the web 41a
from bottom up inside the NYLON bushing 71, and a lower end surface
of the cylindrical part 72a abuts on the plain washer 73. A
ring-shaped flange part 72b is formed in an upper end surface of
the cylindrical part 72a, and this flange part 72b is above the web
41a. The flange part 72b and the web 41a are apart from each other.
An inner diameter of the stepped collar 72 is almost equal to a
diameter of the rod 23c, and an outer diameter of the cylindrical
part 72a is slightly smaller than a diameter of the mounting hole
41g. Thus, there is a space between an outer peripheral surface of
the cylindrical part 72a and the edge of the mounting hole 41g, and
the rod 23c is set with a play back and forth and left and right
with respect to the beam 41.
[0089] A nut 76 is engaged with the rod 23c, a leaf spring 74 is
disposed between the flange part 72b of the stepped collar 72 and
the nut 76, and the nut 76 is engaged with the leaf spring 74. The
leaf spring 74 is formed into an isosceles triangular shape, an
insertion hole is formed in its center (center of gravity of the
isosceles triangle), and the rod 23c is inserted into this
insertion hole. Corners of the leaf spring 74 equal to each other
are covered with covers 75, and grease is applied on the covers 75.
The cover 75 is formed by molding and hardening a fluid resin at
the corner of the leaf spring 74, and a part of the cover 75 is
inserted into a hole 74a formed at the corner of the leaf spring
74. Seen from the side, the leaf spring 74 is curved so that a
center of the leaf spring 74 can be angled, and the corner covered
with the cover 75 is hemmed. By fastening the nut 76, the leaf
spring 74 is held between the nut 76 and the stepped collar 72, the
leaf spring 74, the stepped collar 72 and the plain washer 73 are
held between the nut 76 and the load sensor 23. By fastening the
nut 76, the covers 75 of both hems of the leaf spring 74 abut on
the upper surface of the web 41a of the beam 41 to press the leaf
spring 74 to the web 41a. Since the fastening of the nut 76 causes
elastic deformation of the leaf spring 74, a load is applied on the
nut 76 to prevent its loosening. As the rod 23c is inserted into
the stepped collar 72, even when the nut 76 is excessively
fastened, it is possible to prevent bonding of the entire leaf
spring 74 to the upper surface of the web 41a caused by flat
deformation of the leaf spring 74.
[0090] As the insertion hole inserted into the rod 23c is formed in
the center-of-gravity of the leaf spring 74, seen to the insertion
direction of the rod 23c, the rod 23c is inserted into the
insertion hole in a position shifted from a line for
interconnecting both hem corners of the leaf spring 74 which
becomes a contact between the leaf spring 74 and the web 41a. A
position of the mounting hole 41g in the width direction of the web
41a is slightly right from the center, and both hems of the leaf
spring 74 are in contact with the width-direction center of the web
41a.
[0091] As shown in FIG. 2, a mounting structure of the left front
load sensor 22 to the mounting hole 42f is similar to that of the
right rear load sensor 23 to the mounting hole 41g, and a mounting
structure of the left rear load sensor 24 to the mounting hole 42g
is similar to that of the right front load sensor 21 to the
mounting hole 41f. In other words, the load sensors 21 and 24 at
opposite corners are fixed to the rectangular frame 40 without any
play in a back-and-forth or left-and-right direction, while the
load sensors 23 and 22 at other opposing corners are fixed to the
rectangular frame 40 with play in back-and-forth and left-and-right
directions by an amount equal to a space between the outer
peripheral surface of the cylindrical part 72a and the mounting
hole 41g.
[0092] In the state in which the rectangular frame 40 is mounted on
the load sensors 21 to 24 as described above, the submarine pipe 10
is located on a side behind the front member 43.
[0093] As shown in FIGS. 1 to 2, a side frame 51 is welded to the
right flange 41b of the beam 41, and a side frame 52 is welded to
the left flange 42b of the beam 42. These side frames 51 and 52 are
parts of a bottom frame of the vehicle seat.
[0094] Front parts of the side frames 51 and 52 are covered with a
pan frame 53 from the above, and the side frames 51 and 52 are
connected to the pan frame 53 by bolts and nuts or rivets. A sheet
spring 54 is installed between a cross pipe 44 and the pan frame
53, a cushion is mounted on the pan frame 53 and the sheet spring
54, and the cushion, the pan frame 53 and the side frames 51 and 52
are entirely covered with a cover.
[0095] A backrest frame is connected to rear ends of the side
frames 51 and 52 to rise and fall by a reclining mechanism. The
backrest frame and the cushion are not shown for easier viewing of
the drawings.
[0096] When the passenger's weight measurement device 1 is
assembled, the brackets 11 and 12 and the submarine pipe 10 are
fitted to the assembled slide adjuster 2, the load sensors 21 and
23 are fitted to the upper surface of the right upper rail 5, and
the load sensors 22 and 24 are fitted to the upper surface of the
left upper rail 6. Then, the rectangular frame 40 is fitted to the
load sensors 21 to 24 by using the NYLON bushings 61 and 71, the
stepped collars 62 and 72, the plain washers 63 and 73, the leaf
springs 64 and 74, and the nuts 66 and 76. When the rectangular
frame 40 is fitted, even when positions of the load sensors 21, 23,
22 and 24 are not aligned with those of the mounting holes 41f,
41g, 42f and 42g as designed, errors can be eliminated as the
diameters of the rods 21c and 24c are smaller than the inner
diameter of the stepped collar 62 in the right front and left rear
load sensors 21 and 24.
[0097] When the assembled passenger's weight measurement device 1
is fitted to a vehicle, the brackets 31 to 34 of the slide adjuster
2 are mounted to a floor in the vehicle by bolts and nuts or
rivets. If positions of mounting parts of the brackets 31 to 34 are
not aligned with designed positions of the brackets 31 to 34, when
the brackets 31 to 34 are mounted to the floor, the slide adjuster
2 or the like is slightly distorted. However, as the right rear
load sensor 23 and the left front load sensor 22 are set to play in
the back-and-forth and left-and-right directions of the rectangular
form 40, even when the slide adjuster 2 or the like is distorted,
the load sensors 22 and 23 are horizontally shifted from the
rectangular frame 40 to prevent application of an initial load on
the load sensors 21 to 24 caused by distortion. Moreover, as the
rectangular frame 40 is shifted vertically with respect to the load
sensors 21 to 24 by the stepped collars 62 and 72, application of
an initial load on the load sensors 21 to 24 caused by distortion
of the slide adjuster 2 or the like is prevented. Even when the
load sensors 21 to 24 are shifted with respect to the rectangular
frame 40, as the leaf springs 64 and 74 are present between the
nuts 66 and 76 and the webs 41a and 42a, the load sensors 21 to 24
are not loosened with respect to the rectangular frame 40 thereby
causing no rigidity problem.
[0098] According to the passenger's weight measurement device 1
configured as described above, when a passenger sits on the seat
bottom, a weight of the passenger is applied through the
rectangular frame 40 on the load sensors 21 to 24, and converted
into an electric signal by the load sensors 21 to 24.
[0099] Because of the configuration in which the right load sensors
21 and 23 are mounted between the upper rail 5 and the rectangular
frame 40, the left load sensors 22 and 24 are mounted between the
upper rail 6 and the rectangular frame 40, and the load sensors 21
to 24 move back and forth integrally with the vehicle seat,
irrespective of the back-and-forth position of the vehicle seat, a
load input from the vehicle seat to the load sensors 21 to 24 can
always be maintained constant. Accordingly, it is possible to
improve measuring accuracy of passenger's weight.
[0100] As the submarine pipe 10 is located behind the front member
43, when front collision or the like of the vehicle applies a
forward inertial force on the passenger, a buttocks of the
passenger sitting on the vehicle seat is held by the submarine pipe
10. Thus, it is possible to prevent a so-called submarine
phenomenon in which the passenger gets under a waist belt.
[0101] As the submarine pipe 10 is disposed separately from the
front member 43, the buttocks of the passenger do not come into
contact with the front member 43 at the time of front collision or
the like of the vehicle. Accordingly, the forward inertial force at
the time of front collision or the like of the vehicle is prevented
from being transmitted through the rectangular frame 40 to the load
sensors 21 to 24. Thus, even at the time of front collision or the
like of the vehicle, it is possible to improve measuring accuracy
of the passenger's weight.
[0102] None of the flanges 41b, 41c, 42b and 42c are disposed in
the front end of the beams 41 and 42, only the webs 41a and 42a are
present. The notches 41e and 42e are formed in the front ends 41d
and 42d of the webs 41a and 42a, and the front member 43 is mounted
in front of the notches 41e and 42d. Accordingly, when a large load
is applied on the rectangular frame 40 at the time of front
collision or the like of the vehicle, the beams 41 and 42 are
deformed at the notches 41e and 42d, whereby the load is reduced at
the deformed places. Hence, even when the large load is applied on
the rectangular frame 40, transmission of the large load to the
load sensors 21 to 24 is prevented. Thus, even at the time of front
collision or the like of the vehicle, it is possible to improve
measuring accuracy of the passenger's weight and to suppress
damaging of the load sensors 21 to 24.
Second Embodiment
[0103] FIG. 11 is an exploded perspective assembly diagram showing
a passenger's weight measurement device according to a second
embodiment. FIG. 12 is an exploded perspective assembly diagram of
a seat section including the passenger's weight measurement device
of the second embodiment. FIG. 13 is a perspective appearance
diagram showing the passenger's weight measurement device of the
second embodiment. FIG. 14 is a perspective appearance diagram
showing a schematic configuration of the passenger's weight
measurement device of the second embodiment. FIG. 15 is a
perspective appearance diagram showing the passenger's weight
measurement device of the second embodiment. FIG. 16 is a
longitudinal sectional diagram of an enlarged main section of FIG.
15. FIG. 17 is a plan diagram of an enlarged main section of FIG.
16.
[0104] FIG. 18 is a longitudinal sectional diagram of a first
elastic bushing applied to the passenger's weight measurement
device of the second embodiment. FIG. 19 is a longitudinal
sectional diagram of a load cell located on one diagonal line in
the passenger's weight measurement device of the second embodiment.
FIG. 20 is a longitudinal sectional diagram of a load cell located
on the other diagonal line in the passenger's weight measurement
device of the second embodiment.
[0105] Referring to FIGS. 11 and 12, a pair of slide rails 2a and
2b are arranged in a vehicle floor. A seat includes a seat 400 and
a backrest 50, and the seat 400 is supported by a pair of side
frames 3a and 3b. Load cells 100 are disposed at four corners of
the pair of slide rails 2a and 2b and the pair of side frames 3a
and 3b. A seat frame 30 includes a pair of side frames 3a and 3b
extending in parallel, and a set of first connection frames 3c and
3d for connecting both ends of the pair of side frames 3a and 3b to
be perpendicular to the side frames 3a and 3b. In the pair of slide
rails 2a and 2b, a pair of first slide rails 21a and 21b and a pair
of second slide rails 22a and 22b are connected so as to be
respectively slidable.
[0106] The passenger's weight measurement device is usually
disposed in a passenger seat of a vehicle to detect a weight of a
passenger of the seat. An airbag system mounted on the passenger
seat is controlled corresponding to a detection signal obtained by
the passenger's weight measurement device. It is possible to
estimate the weight of the passenger of the seat via the
passenger's weight measurement device provided between the seat 400
and the vehicle floor. In FIG. 12, cushions of the seat 400 and the
backrest 50 are omitted.
[0107] Referring to FIGS. 11 and 12, the pair of side frames 3a and
3b are C channel members in which both wings are bent. Such a C
channel member can effectively enlarge sectional secondary moment
by contriving the shapes without increasing weight, and rigidity to
a bending force can be improved. The pair of side frames 3a and 3b
are arranged in the vehicle with bent pieces of both wings set
upward.
[0108] Referring to FIGS. 11 and 12, the first connection frame 3c
of the set of first connection frames 3c and 3d is made of a C
channel member in which both wings are bent. Both ends of the first
connection frame 3c are connected to one end of the pair of the
side frames 3a and 3b. The pair of side frames 3a and 3b and the
first connection frame 3c are connected together by fasteners such
as screws. The first connection frame 3d of the set of first
connection frames 3c and 3d is a round pipe. Both ends of this
round pipe are connected to the other ends of the pair of side
frames 3a and 3b.
[0109] Referring to FIGS. 11 and 12, the pair of first slide rails
21a and 21b extend in parallel to be fixed to the vehicle floor
side. The pair of first slide rails 21a and 21b include a second
connection frame 21c for connecting middle parts of the pair of
first slide rails 21a and 21b to be perpendicular to the first
slide rails 21a and 21b. The pair of first slide rails 21a and 21b
each includes a slide locking device not shown in the drawings, and
a lever 23 is connected to operate the slide locking device. The
seat 400 can be slid by gripping the lever 23. The pair of second
slide rails 22a and 22b extend in parallel and include a third
connection frame 22c for connecting middle parts of the pair of
second slide rails 22a and 22b to be perpendicular to the second
slide rails 22a and 22b.
[0110] Referring to FIGS. 11 and 12, both ends of the pair of first
slide rails 21a and 21b are fixed to the vehicle floor via a pair
of support brackets 24 and 25. The second connection frame 21c is a
wide C channel member, and both ends of the second connection frame
21c are connected to the middle parts of the pair of first slide
rails 21a and 21b.
[0111] Referring to FIGS. 11 and 12, the third connection frame 22c
includes a round pipe 220 and a pair of angle members 221 and 222,
and the angle members 221 and 222 are connected to both ends of the
round pipe 220 so that pieces thereof can face each other. For
example, the angle members 221 and 222 and the round pipe 220 may
be bonded together by welding, or caulking. The other pieces of the
angle members 221 and 222 are connected to the middle parts of the
pair of second slide rails 22a and 22b. Both ends of the third
connection frame 22c are connected to the middle parts of the pair
of second slide rails 22a and 22b by fasteners such as screws.
[0112] Referring to FIG. 14, the pair of side frames 3a and 3b and
the set of first connection frames 3c and 3d are connected together
so that a highly rigid rectangular seat frame 30 can be obtained.
The seat frame 30 holds the seat 400 (FIG. 12). In this case, high
rigidity of the seat frame 30 may mean that distortion of the seat
frame 30 is small with respect to a force applied on the seat frame
30, for example, displacement of the pair of side frames 3a and 3b
is small with respect to a force (compression stress) applied in a
mutually approaching direction of the pair of side frames 3a and
3b, or displacement of the pair of side frames 3a and 3b is small
with respect to a force (tension stress) applied in a mutually
separating direction of the pair of side frames 3a and 3b.
[0113] Referring to FIG. 14, the pair of first slide rails 21a and
21b and the second connection frame 21c are connected together to
obtain a highly rigid H-shaped frame (H-frame). The pair of second
slide rails 22a and 22b and the third connection frame 22c are
connected together to obtain a highly rigid H-frame. The high
rigidity of the H-frame may mean that distortion of the H-frame is
small with respect to a force applied on the H-frame, for example,
displacement of the pair of slide rails 2a and 2b is small with
respect to a force (compression stress) applied in a mutually
approaching direction of the pair of slide rails 2a and 2b, or
displacement of the pair of slide rails 2a and 2b is small with
respect to a force (tension stress) applied in a mutually
separating direction of the pair of slide rails 2a and 2b (FIGS. 11
and 12).
[0114] Referring to FIGS. 11 and 12, in the passenger's weight
measurement device, four load cells 100 are arranged at four
corners of the pair of second slide rails 22a and 22b. The four
load cells 100 connect the seat frame 30 to the pair of second
slide rails 22a and 22b.
[0115] Referring to FIGS. 11 and 12, a weight of a passenger of the
seat 400 can be estimated by summing up detection values of the
four load cells 100. The load cell 1 includes a male screw 1a in
one end, and a flange 1b in the other end located to face one end.
The male screw 1a is connected to the seat frame 30. The connection
means a connection to enable up-and-down movement in an axial
direction, or a connection to enable up-and-down movement in axial
and circumferential directions. The flange 1b is connected to the
pair of second slide rails 22a and 22b. The flange 1b is connected
to the pair of second slide rails 22a and 22b by a fastener
constituted of a hexagon socket bolt 1h and a nut 1j (FIG. 19).
[0116] According to the passenger's weight measurement device of
the present invention, the pair of side frames 3a and 3b supporting
the seat and the set of the first connection frames 3c and 3d are
interconnected to obtain the highly rigid rectangular frame seat
frame 30. The pair of slide rails 21a and 21b and the second
connection frame 21c are interconnected to obtain the highly rigid
H-frame, and the pair of slide rails 22a and 22b and the third
connection frame 22c are interconnected to obtain the highly rigid
H-frame. For example, the pair of side frames 3a and 3b move in a
mutually separating direction to enable prevention of tilting of
the load cells 100. According to the present invention, it is
possible to provide the passenger's weight measurement device
capable of preventing interferences with load measurement of the
load cells without increasing the number of components and without
greatly changing the framework of the conventional seat
structure.
[0117] Referring to FIG. 13, in the passenger's weight measurement
device of the present invention, among the four load cells 100aa,
100ab, 100ba and 100bb the pair of load cells 100aa and 100bb
located on one diagonal line are connected to the seat frame 30 to
be movable up and down. The pair of load cells 100ab and 100ba
located on the other diagonal line are connected to the seat frame
30 to be movable up and down and play. Four load cells, 1aa, 1ab,
1ba, and 1bb shown in FIG. 13 are the same as the load cells 100
shown in FIGS. 11 and 12, but they are denoted by reference
numerals to be differentiated for convenience of explanation.
[0118] As described above, the load cell 1 includes the male screw
1a in one end, and the flange 1b in the other end located to face
one end (FIG. 14). In FIG. 13, the connection of the pair of load
cells 100aa and 100bb to the seat frame 30 to be movable up and
down is equivalent to connection of the pair of male screws 100a
and 100ato the seat frame 30 to move up and down. The connection of
the pair of load cells 1ab and 1ba to the seat frame 30 to move up
and down and play is equivalent to connection of the pair of male
screws 1a and 1a to the seat frame 30 to be movable and play up and
down.
[0119] The passenger's weight measurement device of the present
invention can absorb manufacturing errors of the pair of slide
rails 22a and 22b, the four load cells 100, and the pair of side
frames 3a and 3b, and height-direction accumulated errors of these
components. The device can also absorb assembling errors of the
pair of slide rails 22a and 22b, the four load cells 100 and the
seat frame 30. The up-and-down movable connection structure and the
up-and-down movable and playable connection structure should
preferably be realized by general mechanical elements such as
bushings or washers without using any special mechanical elements.
A specific embodiment will be described below.
[0120] According to the passenger's weight measurement device of
the present invention, among the set of first connection frames 3c
and 3d, the first connection frame 3c is connected to one end of
the pair of side frames 3a and 3b to be easily deformed by shocks
having a predetermined or more strength (FIG. 15).
[0121] Referring to FIG. 15, in the pair of side frames 3a and 3b,
a pair of tongue pieces 33a and 33b extend to one end. The first
connection frame 3c is connected to tips of the pair of tongue
pieces 33a and 33b. Constricted parts 34a and 34b are disposed in
base ends of the pair of tongue pieces 33a and 33b (FIG. 17).
Stress due to shocks concentrates on the pair of constricted parts
34a and 34b. Accordingly, it is possible to protect the load cells
from shocks having a predetermined or more strength by employing
the structure to be easily deformed by shocks having a
predetermined or more strength.
[0122] As shown in FIG. 16, the pair of cushion frames constituting
the seat 400 are connected to the round pipe 220. However,
according to the passenger's weight measurement device of the
present invention, the pair of second slide rails 22a and 22b are
connected together by the round pipe 220 (FIG. 11). Thus, by
changing the fixation of the round pipe 220 for receiving a load of
the passenger during collision from the pair of cushion frames to
the pair of second slide rails 22a and 22b, it is possible to
protect the load cells from shocks having a predetermined or more
strength.
[0123] Next, a load cell mounting structure of the passenger's
weight measurement device of the present invention will be
described.
[0124] Referring to FIG. 14, the load cell 1 includes the male
screw 1a in one end. The load cell 1 includes the flange 1b in the
other end located to face one end. In the seat frame 30, four holes
3aa, 3ab, 3ba and 3bb for entering male screws are formed
corresponding to the arrangement of the four load cells 100. The
pair of second slide rails 22a and 22b fix the flanges 1b.
[0125] Referring to FIGS. 14 and 19, first elastic bushings 31b are
inserted into the pair of first holes 3aa and 3bb located on one
diagonal line. A first collar 31k is elastically provided between
the first elastic bushing 31b and the male screw 1a. A plain washer
1w and a conical spring washer 1s are mounted on the first collar
31k, and a nut 1n is connected to the male screw 1a.
[0126] For example, the first elastic bushing is made of a
synthetic resin such as NYLON (registered trademark). The bushing
is a ring-shaped member, and called a grommet. The bushing includes
a groove in an outer peripheral direction, and this groove is
engaged with peripheral edges of the first holes 3aa and 3bb. For
example, the insertion of the first elastic bushings 31b into the
pair of first holes 3aa and 3bb may be press-insertion of the first
elastic bushings into the first holes 3aa and 3bb. An inner
periphery of the first elastic bushing 31b elastically abuts on an
outer periphery of the first collar 31k (FIG. 19).
[0127] Referring to FIG. 19, in a portion of the seat frame 30,
which is engaged with the pair of male screws located on one
diagonal line, the up-and-down moving amount thereof is defined by
an axial-direction length of the first collar 31k. The conical
spring washer 1s presses the seat frame 30 to the load cell 1
side.
[0128] Referring to FIG. 19, the first collar 31k includes a
circular flange in on end. The first collar 31k is inserted into
the male screw 1a from this flange. Then, the first collar 31k is
inserted into the first hole 3aa and 3bb equipped with the first
elastic bushings 31b. At this time, one surface of the first
elastic bushing 31b abuts on the flange of the first collar 31k.
The plain washer 1w is inserted into the male screw 1a. At this
time, for example, the other surface of the first elastic bushing
31b is separated from the plain washer 1w while the plain washer 1w
abuts on the other end of the first collar 31k. Subsequently, the
conical spring washer 1s is mounted, and the nut 1n is connected to
the male screw 1a. The nut 1n is preferably a torque nut.
[0129] According to the passenger's weight measurement device of
the present invention, it is possible to realize the up-and-down
movable structure by general mechanical elements without using any
special mechanical elements. Besides, it is possible to absorb
manufacturing errors of the pair of slide rails 22a and 22b, the
four load cells 100, and the pair of side frames 3a and 3b, and
height-direction accumulated errors of these components.
[0130] Referring to FIGS. 14 and 20, the second elastic bushing 32b
is inserted into the pair of second holes 3ab and 3ba located on
the other diagonal line. The second elastic bushing 32b includes a
groove disposed in an outer peripheral direction, and this groove
is engaged with peripheral edges of the second holes 3ab and 3ba.
For example, the insertion of the second elastic bushings 32b into
the pair of second holes 3ab and 3ba may be press-insertion of the
second elastic bushings 32b into the second holes 3ab and 3ba. In
FIG. 20, an inner diameter of the second elastic bushing 32b is
larger than an outer diameter of the second collar 32k, and the
second elastic bushing 32b holds the second collar 32k to play. The
play may be movement with play, and it is possible to absorb
manufacturing errors of the pair of slide rails 22a and 22b, the
four load cells 100 and the pair of side frames 3a and 3b, and
horizontal assembling errors of these components.
[0131] Referring to FIGS. 14 and 20, the plain washer 1w is first
inserted into the male screw part 1a. Then, the second holes 3ab
and 3ba equipped with the second elastic bushings 32b are inserted
into the male screws 1a. The second collar 32k includes a circular
flange in one end. The second collar 32k is inserted into the male
screw 1a with this flange as a tail end. At this time, for example,
an outer periphery of the second collar 32k is separated from an
inner periphery of the second elastic bushing 32b. The conical
spring washer 1s is mounted, and the nut 1n is connected to the
male screw 1a. For example, the first and second elastic bushings
31b and 32b may be identical, and used by changing an insertion
order and direction into the male screws 1a.
[0132] According to the passenger's weight measurement device of
the present invention, it is possible to realize the up-and-down
movable and playable structure by general mechanical elements
without using any special mechanical elements. Moreover, it is
possible to absorb manufacturing errors of the pair of slide rails
22a and 22b, the four load cells 100, and the pair of side frames
3a and 3b, and height-direction accumulated errors of these
components.
[0133] Referring to FIG. 18, the inner diameter of the first
elastic bushing 31b is formed into a conical shape, and an inner
periphery of an upper bottom surface of the conical form of a small
radius abuts on the outer periphery of the first collar 31k (FIG.
19). Thus, it is possible to simultaneously achieve assembling
easiness and assembling error absorption by forming the inner
diameter of the first elastic bushing 31b into the conical
shape.
[0134] According to the passenger's weight measurement device of
the present invention, the pair of side frames 3a and 3b supporting
the seat are connected to the set of first connection frames 3c and
3d to obtain a highly rigid rectangular frame seat frame 30. The
pair of slide rails 21a and 21b and the second connection frame 21c
are connected together to obtain a highly rigid H-frame. The pair
of slide rails 22a and 22b and the third connection frame 22c are
connected together to obtain a highly rigid H-frame. For example,
the pair of side frames 3a and 3b move in a mutually separating
direction to enable prevention of tilting of the load cells 100.
According to the present invention, it is possible to provide the
passenger's weight measurement device capable of preventing
interferences with load measurement of the load cells without
increasing the number of components and without greatly changing
the framework of the conventional seat structure.
[0135] According to the passenger's weight measurement device of
the present invention, it is possible to absorb manufacturing
errors of the pair of slide rails 22a and 22b, the four load cells
100, and the pair of side frames 3a and 3b, and height-direction
accumulated errors of these components. Besides, it is possible to
absorb horizontal accumulated errors of these components caused by
assembling.
[0136] The present invention is not limited to the first and second
embodiments. Various improvements and design changes can be made
without departing from the gist of the invention.
* * * * *