U.S. patent application number 10/874304 was filed with the patent office on 2004-12-30 for headrest apparatus for a vehicle seat.
This patent application is currently assigned to AISIN SEIKI KABUSHIKI KAISHA.. Invention is credited to Mori, Masatoshi, Terada, Takami.
Application Number | 20040262974 10/874304 |
Document ID | / |
Family ID | 33411155 |
Filed Date | 2004-12-30 |
United States Patent
Application |
20040262974 |
Kind Code |
A1 |
Terada, Takami ; et
al. |
December 30, 2004 |
Headrest apparatus for a vehicle seat
Abstract
According to an aspect of the present invention, a headrest
apparatus for a vehicle seat includes a support portion mounted on
the vehicle seat, a movable portion supported at the support
portion for moving forward, a first arm and a second arm being
crossed and rotatably connected each other by a rotation axis and
supporting the movable portion to the support portion, and a
biasing member provided between the support portion and the movable
portion for biasing the movable portion forward relative to the
support portion.
Inventors: |
Terada, Takami; (Toyota-shi,
JP) ; Mori, Masatoshi; (Anjo-shi, JP) |
Correspondence
Address: |
Finnegan, Henderson, Farabow,
Garrett & Dunner, L.L.P.
1300 I Street, N.W.
Washington
DC
20005-3315
US
|
Assignee: |
AISIN SEIKI KABUSHIKI
KAISHA.
|
Family ID: |
33411155 |
Appl. No.: |
10/874304 |
Filed: |
June 24, 2004 |
Current U.S.
Class: |
297/407 |
Current CPC
Class: |
B60N 2/865 20180201;
B60N 2/888 20180201; B60N 2002/0264 20130101 |
Class at
Publication: |
297/407 |
International
Class: |
A47C 004/54 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 27, 2003 |
JP |
2003-185602 |
Claims
1. A headrest apparatus for a vehicle seat comprising: a support
portion being adapted to be mounted on the vehicle seat; a movable
portion supported at the support portion for moving forward; a
first arm and a second arm being crossed and rotatably connected
each other by a rotation axis and supporting the movable portion to
the support portion; and a biasing means provided between the
support portion and the movable portion for biasing the movable
portion forward relative to the support portion.
2. The headrest apparatus according to claim 1, wherein the first
arm and the second arm rotate to open in an fore-aft direction by
biasing force of the biasing means to move the movable portion from
an original position to an extended position; and wherein the first
arm and the second arm rotate to close in the fore-aft direction to
move the movable portion from the extended position to the original
position.
3. The headrest apparatus according to claim 2, wherein a first end
of the first arm is rotatably connected to the support portion and
a second end of the first arm is rotatably and slidably connected
to the movable portion; and wherein a first end of the second arm
is rotatably connected to the movable portion and a second end of
the second arm is rotatably and slidably connected to the support
portion.
4. The headrest apparatus according to claim 3, further comprising:
a stopper member (15) for restraining a sliding movement of the
second end of the first arm relative to the movable portion and a
sliding movement of the second end of the second arm relative to
the support portion to maintain the movable portion at the extended
position.
5. The headrest apparatus according to claim 3, further comprising:
a lock member couples either one of the first and second ends of
the first arm and either one of the first and second ends of the
second arm for stopping the first and the second arms to prevent
relative movement thereof in the fore-aft direction to maintain the
movable portion at the original position.
6. The headrest apparatus according to claim 1, wherein the biasing
means includes a coil spring coiled about the rotation axis of the
first arm and the second arm; and wherein the coil spring couples
one end of the first arm and one end of the second arm.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35
U.S.C. .sctn. 119 to Japanese Patent Application 2003-185602, filed
on Jun. 27, 2003, the entire content of which is incorporated
herein by reference.
FIELD OF THE INVENTION
[0002] This invention generally relates to a headrest apparatus
adapted to a vehicle seat.
BACKGROUND OF THE INVENTION
[0003] A known headrest apparatus is described in U.S. patent
publication No. 2003/057758. The known headrest apparatus includes
a fixed support portion and a pre-stressed movable portion. The
support portion and the movable portion are connected via upper and
lower levers arranged in parallel with each other. The known
headrest further includes a spring for applying the pre-stress to
the movable portion.
[0004] According to the known headrest apparatus, when the vehicle
crash or pre-crash notice is detected, pre-stress applied to the
movable portion by the spring is released by a trigger apparatus to
move the movable portion forward relative to the support portion.
Thus, distance between a head of an occupant and the headrest
becomes proper to reduce injuries given to the head or lower part
of neck of the occupant.
[0005] Notwithstanding, with the construction of the known U.S.
patent publication No. 2003/057758, in order to transmit restoring
force of the spring to the upper and lower levers when pre-stress
applied to the movable portion is released, the known headrest
apparatus further includes a spring lever for transmitting the
restoring force of the spring to the lower lever and a connecting
lever for transmitting the restoring force of the spring
transmitted from the lower lever to the upper lever, which includes
complex construction.
[0006] A need thus exists for a headrest with more simple
mechanism.
SUMMARY OF THE INVENTION
[0007] According to an aspect of the present invention, a headrest
apparatus for a vehicle seat includes a support portion provided at
a seatback of a vehicle seat, a movable portion supported at the
support portion for moving forward, a first arm and a second arm
being crossed and rotatably connected each other by a rotation axis
and supporting the movable portion to the support portion, and a
biasing means provided between the support portion and the movable
portion for biasing the movable portion forward relative to the
support portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The foregoing and additional features and characteristics of
the present invention will become more apparent from the following
detailed description considered with reference to the accompanying
drawings, wherein:
[0009] FIG. 1 shows a front view of a headrest according to an
embodiment of the present invention.
[0010] FIG. 2 shows a cross-sectional view taken on line II-II of
FIG. 1.
[0011] FIG. 3 shows a perspective view of an internal mechanism of
the headrest according to the embodiment of the present
invention.
[0012] FIG. 4 shows a cross-sectional view showing an arrangement
of a coil spring at a non-extended position (original position) of
the headrest according to the embodiment of the present
invention.
[0013] FIG. 5 shows a cross-sectional view showing an arrangement
of the coil spring at an extended position of the headrest
according to the embodiment of the present invention.
[0014] FIG. 6 shows a cross-sectional view taken on line VI-VI of
FIG. 1 at the non-extended position of the headrest according to
the embodiment of the present invention.
[0015] FIG. 7 shows a cross-sectional view taken on line VII-VII of
FIG. 1 at the extended position of the headrest according to the
embodiment of the present invention.
[0016] FIG. 8 shows a cross-sectional view taken on line VIII-VIII
of FIG. 1 in the non-extended position of the headrest according to
the embodiment of the present invention.
[0017] FIG. 9 shows a cross-sectional view showing an operation of
a stopper member according to the embodiment of the present
invention.
[0018] FIG. 10 shows a cross-sectional view taken on line X-X of
FIG. 1 in the extended position of the headrest according to the
embodiment of the present invention.
DETAILED DESCRIPTION
[0019] One embodiment of the present invention will be explained
with reference to the illustrations of the drawing figures as
follows. As shown in FIG. 1, a headrest 1 includes a headrest body
2 and a pair of headrest stays 3. The headrest stays 3 support the
headrest body 2 relative to a seat back of the vehicle seat 17.
First ends of the headrest stays 3 are connected to the headrest
body 2 so that the headrest stays 3 support the headrest body 2.
Second ends of the headrest stays 3 are accommodated in the seat
back of the vehicle seat 17 to support the headrest body 2. The
height of the headrest body 2 is adjustable by a known constitution
arranged between the seat back of the vehicle seat 17 and the
headrest stays 3.
[0020] As shown in FIG. 2, the headrest body 2 includes a support
portion 4 and a movable portion 5. The support portion 4 includes a
first bracket 6. The first bracket 6 is made from a metal plate, or
the like. The bracket 6 is fixed, for example, via welding at the
headrest stays 3 whose a first end of each support stay 3 is
projected from the support portion 4, and a second end of each
support stay 3 is positioned in the support portion 4. The first
bracket 6 may be fixed at the headrest stays 3 via a bolt, a screw
cramp, a rivet caulking or the like. As shown in FIG. 3, the first
bracket 6 is configured to have two lateral surfaces 6W formed, for
example, by bending two opposite sides of the metal plate, or the
like. The first bracket 6 includes approximate U-shape in
cross-section. The lateral surfaces have attachment holes 6a and 6b
respectively. The attachment holes 6b are vertically elongated
along the vertical orientation of the first bracket 6, that is, the
vertical orientation of the headrest body 2. In the meantime, as
shown in FIG. 2, the movable portion 5 includes a second bracket 7.
The second bracket 7 is configured to have lateral surfaces 7W, for
example, by bending a metal plate, or the like, likewise the first
bracket 6. The second bracket 7 is provided at the movable portion
5 and opposing to the first bracket 6. Each lateral surface 7W
includes attachment holes 7a, 7b. The attachment holes 7b are
vertically elongated along with vertical orientation of the
headrest body 2, likewise the attachment hole 6b.
[0021] As shown in FIGS. 2 and 3, the first bracket 6 and the
second bracket 7 are connected each other via X links 8 including
arms 8a, 8b and a corresponding pin 9 (a rotation axis). The arm 8a
and the arm 8b are crossed each other to be rotatably connected via
the pin 9 serving as a connecting portion.
[0022] As shown in FIG. 3, the X links 8 are connected to the first
bracket 6 via rods 10a, 10b. The X links 8 are provided at both
ends of the rods 10a and 10b, in other words, at the both lateral
surfaces of the first bracket 6. Each X link 8 is connected each
other via the rods 10a and 10b. The rod 10a is positioned through
an attachment holes & provided at the end portion of the arms
8a and its corresponding attachment holes 6a provided at the first
bracket 6. The rod 10b is positioned through an attachment holes 8d
provided at the end portion of the arms 8b and their corresponding
vertically elongated attachment holes 6b provided at the first
bracket 6. Thus, the X links 8 and the first bracket 6 are
connected. Further, as shown in FIG. 2, likewise the first bracket
6, a rod 11a is positioned through the attachment holes 8c provided
at the end portion of the arms 8b and the corresponding attachment
holes 7a, and a rod 11b is positioned through the attachment holes
8d provided at the end portion of the arms 8a and the corresponding
vertically elongated attachment holes 7b provided at the second
bracket 7, thus to connect the X links 8 and the second bracket 7.
In other words, the X links 8 are slidably connected to the first
bracket 6 and the second bracket 7 via the rod 11b in the
vertically elongated attachment holes 6b, 7b.
[0023] As shown in FIGS. 3-5, a coil spring 12 serving as biasing
means for opening the X-links 8 is provided at the headrest 1. A
leaf spring, a spiral spring, a cylinder apparatus using hydraulic
pressure or air pressure may serve as the biasing means for opening
the X links 8. The coil spring 12 includes a coil portion 12c and
hook portions 12f extended from the both end of the coil. At least
one end of one of the pins 9 is elongated to be positioned through
the coil portion 12c and thus to support the coil portion 12c.
Further, each hook portion 12f is provided to hook the rods 10a and
11a respectively against the biasing force of the coil portion 12c.
Accordingly, the coil spring 12 biases the X links 8 for expanding
orientation.
[0024] When the headrest 1 is at a non-extended position (original
position) without any notice of the pre-crash tendency or shock
from the crash, as shown in FIGS. 4 and 6, the X links 8 and the
rods 10a, 10b, 11a, 11b connected to the X links 8 are closed while
provided with the biasing force from the coil spring 12, and the
state of the X links 8 at the non-extended position is maintained
by lock members 13a, 13b between the rods 10a, 11a so that the
movable portion 5 does not extend forward. The lock member 13a is
rotatably positioned about the rod 11a and includes a hook portion
13f at a first end of the lock member 13a. The lock member 13b is
positioned about the rod 10a and selectively engaged with the hook
portion 13f. In case that the hook portion 13f engages with the
lock member 13b, the headrest 1 is maintained at the non-extended
position. A spring SP (shown in FIG. 6) is provided between the
lock member 13a and the movable portion 5. The spring SP biases the
lock member 13a to engage with the lock member 13b.
[0025] As shown in FIG. 6, in order to extend the movable portion 5
forward from the non-extended position, a holding by the lock
members 13a, 13b at the non-extended position of the headrest 1 is
released. The lock is released by a releasing apparatus 14 attached
at the first bracket 6. As the releasing apparatus 14, for example,
a solenoid apparatus is used. The solenoid apparatus is connected
to the sensor for detecting the shock, and operates with the input
of electric signal from the sensor. A mechanical sensor including
the function of the sensor for detecting the shock may be included
for the releasing apparatus 14.
[0026] The operation of the headrest 1 from the non-extended
position to the extended position will be explained as follows.
[0027] The pre-crash tendency or shock from the crash are detected
by the sensor, or the like, and transmitted to the releasing
apparatus 14 shown in FIG. 6 as an electric signal. Receiving an
electric input by the releasing apparatus 14, a plunger 14a of the
solenoid apparatus serving as the releasing apparatus 14 moves
upward relative to the releasing apparatus 14. As shown in FIG. 6
and FIG. 7, a second end of the lock member 13a always contacts the
plunger 14a at the non-extended position of the headrest 1. The
lock member 13a rotates counterclockwise about the rod 11a serving
as the attachment portion, when the plunger 14a moves upward by the
operation of the releasing apparatus 14. Thus, as shown in FIG. 7,
the lock between the lock member 13a and 13b is released.
[0028] With the release of the lock, as shown in FIG. 4 and FIG. 5,
the biasing force from the coil spring 12 is applied to the rods
10a, 11a. Simultaneously, the arms 8a, 8b of the X links 8
connected to the rods 10a, 11a rotates about the corresponding pin
9 to extend in the fore-aft direction. Accordingly, the rods 10b,
11b slide upward along the attachment holes 6b, 7b respectively
provided at the first bracket 6 and the second bracket 7. When the
rods 10b, 11b reach the upper end of the attachment holes 6b and
7b, the extension of the X links 8, in other words, the forward
extension of the movable portion 5 is completed.
[0029] The movable portion 5 extends forward to support the head of
the occupants at the sudden backward swing by an inertial force due
to the crash. A stopper member 15 is included at the headrest 1, as
shown in FIGS. 8, 9 and 10 to maintain the forward extended state
of the headrest 1 even in the case that the force for returning to
the non-extended position is applied to the movable portion 5. The
stopper member 15 is vertically elongated and rotatably positioned
about the rod 10a. The stopper member 15 includes a claw-like hook
portion 15a. The lower end of the stopper member 15 and the first
bracket 6 are connected via a spring 16. By biasing force of the
spring 16, the stopper member 15 is always biased in the direction
counterclockwise to rotate about the rod 10a serving as the
attachment portion. The operation of the stopper member 15 will be
explained as follows.
[0030] In case the holding between the lock members 13a and 13b as
shown in FIG. 6 is released at the non-extended position of the
headrest 1 shown in FIG. 8, the rod 10b positioned through the
attachment hole 6b provided at the first bracket 6 slides upward
along the attachment hole 6b along with the extension of the
movable portion 5 as shown in FIG. 8 and FIG. 9. In this action,
the rod 10b slides upward while pushing the hook portion 15a formed
at the stopper member 15 relatively (in this case the stopper
member 15 rotates clockwise) against the restoring force of the
spring 16. When the rod 10b exceeds the formed zone of the hook
portion 15a, the stopper member 15 is pulled by the
counterclockwise restoring force of the spring 16 about the rod 10a
serving as the attachment portion. Then as shown in FIG. 10, the
movement of the rod 10b is restrained by the operation of the hook
portion 15a formed at the stopper member 15. Under this condition,
the rod 10b is structurally locked even if the force likely to
return the movable portion 5 to the non-extended position is
applied. Thus, because the X links 8 do not close under this state,
the movable portion 5 does not return to the non-extended position.
Accordingly, extended forward state of the movable portion 5 is
maintained, to securely support the head of the occupants. By
providing plural claw-like hook portions or a stepped claw-like
hook portion, plural extended positions of the movable portion may
be available.
[0031] A procedure for the recovery of the movable portion 5 from
the extended position as shown in FIG. 10 to non-extended position
is explained as follows.
[0032] As shown in FIG. 10, under the condition that the movable
portion 5 is positioned at the extended forward position, as the
foregoing explanation, the movement of the rod 10b is restrained in
the attachment hole 6b by the stopper member 15. The stopper member
15 is connected to the first bracket 6 via the spring 16. In such
condition, by pulling, for example, the lower end of the stopper
member 15 in the clockwise direction against the biasing force of
the spring 16, the restraint of the movement of the rod 10b is
released. In this case, the restraint of a rotation of the arms 8a,
8b about the corresponding pin 9 is released simultaneous with the
release of the restraint of the movement of the rod 10b. Thus, the
biasing force of the coil spring 12 affects to extend the X links 8
as shown in FIG. 5. Accordingly, by applying the force exceeding
the biasing force, the movable portion 5 extended forward recovers
to the non-extended position.
[0033] Further, because the plunger 14a cooperating the operation
of the releasing apparatus 14 at the non-extended position of the
headrest 1 contacts to the releasing apparatus 14 as shown in FIG.
6, the sensitivity for actuating the headrest 1 to the extended
position cooperating with the operation of the releasing apparatus
14 is increased effectively.
[0034] The principles, a preferred embodiment and mode of operation
of the present invention have been described in the foregoing
specification. However, the invention which is intended to be
protected is not to be construed as limited to the particular
embodiment disclosed. Further, the embodiment described herein is
to be regarded as illustrative rather than restrictive. Variations
and changes may be made by others, and equivalents employed,
without departing from the spirit of the present invention.
Accordingly, it is expressly intended that all such variations,
changes and equivalents which fall within the spirit and scope of
the present invention as defined in the claims, be embraced
thereby.
* * * * *