U.S. patent application number 11/396636 was filed with the patent office on 2006-10-12 for seatbelt apparatus.
This patent application is currently assigned to TAKATA CORPORATION. Invention is credited to Masahiro Higuchi, Yasuo Itoga.
Application Number | 20060226694 11/396636 |
Document ID | / |
Family ID | 36617175 |
Filed Date | 2006-10-12 |
United States Patent
Application |
20060226694 |
Kind Code |
A1 |
Higuchi; Masahiro ; et
al. |
October 12, 2006 |
Seatbelt apparatus
Abstract
A seatbelt apparatus is provided which can constrain a passenger
by ensuring removal of a slack of a lap belt when two pretensioners
are activated under two different time frames. A pretensioner of a
seatbelt retractor is activated first, and a shoulder belt and a
lap belt are pulled in a direction toward the seatbelt retractor.
Subsequently, a pretensioner of a belt anchor portion is activated
and pulls a seatbelt toward the belt anchor portion, and hence a
one-way tongue catches and locks the seatbelt. Accordingly, the
shoulder belt is prevented from moving toward the lap belt through
the tongue. Therefore, removal of the slack of the lap belt is
ensured, and hence a lumber of the passenger is firmly fixed.
Inventors: |
Higuchi; Masahiro; (Tokyo,
JP) ; Itoga; Yasuo; (Tokyo, JP) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
TAKATA CORPORATION
|
Family ID: |
36617175 |
Appl. No.: |
11/396636 |
Filed: |
April 4, 2006 |
Current U.S.
Class: |
297/480 ; 24/633;
280/801.1; 280/806; 297/483 |
Current CPC
Class: |
Y10T 24/4016 20150115;
B60R 22/1855 20130101; Y10T 24/45623 20150115; B60R 2022/1812
20130101; B60R 2022/4609 20130101; B60R 22/4604 20130101 |
Class at
Publication: |
297/480 ;
280/801.1; 280/806; 024/633; 297/483 |
International
Class: |
B60R 22/00 20060101
B60R022/00; A44B 11/25 20060101 A44B011/25; B60R 22/46 20060101
B60R022/46 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 7, 2005 |
JP |
2005-110462 |
Claims
1. A seatbelt apparatus comprising: a seatbelt including a shoulder
belt for constraining an upper half body of a passenger and a lap
belt for constraining a lumber of the passenger; a seatbelt
retractor for withdrawably retracting the seatbelt and locking the
seatbelt from being retracted in case of emergency; a belt anchor
portion for fixing a distal end of the seatbelt withdrawn from the
seatbelt retractor to a vehicle body; a tongue slidably supported
by the seatbelt and partitioning between the shoulder belt and the
lap belt; a buckle fixed to the vehicle body and capable of being
engaged by the tongue; a first and a second pretensioner, wherein
each may be provided in at least two devices selected from the
seatbelt retractor, the belt anchor portion and the buckle, wherein
the first and second pretensioners are activated to pull the
seatbelt in case of emergency, and the first and second
pretensioners are adapted to be activated under two time frames in
such a manner that the second pretensioner is activated after
having activated the first pretensioner; and a belt one-way
movement preventing mechanism for preventing the shoulder belt from
moving toward the lap belt when the second pretensioner is
activated.
2. A seatbelt apparatus according to claim 1, wherein the tongue is
a one-way tongue which prevents the shoulder belt from moving
toward the lap belt when a predetermined pulling force toward the
shoulder belt is applied to the seatbelt and, in this state, a
force larger than the predetermined pulling force is applied to the
seatbelt in the direction toward the lap belt.
3. A seatbelt apparatus according to claim 1, wherein the tongue
further comprises: a plate covered by a mold; and a webbing guide
for preventing the webbing from moving in a direction when a
predetermined force is applied to the seatbelt, the webbing guide
including a lock bar configured so that the webbing is secured
between the lock bar and the mold when the force is applied.
4. A seatbelt apparatus according to claim 3, wherein the plate is
formed of a substantially T-shaped metallic plate having a
laterally extending portion and a vertically extending portion
extending vertically from a center of the laterally extending
portion, wherein the laterally extending portion is formed with a
first square opening extending in the lateral direction and the
vertically extending portion is formed with a second square opening
extending in the vertical direction adapted so that a latch member
of the buckle engages the second square opening; and a first and
second side wall extend at a first and second end of the laterally
extending portion, wherein the first and second side walls are each
formed with at least one hole of the same size and at least one
recessed groove of the same size.
5. A seatbelt apparatus according to claim 3, wherein the webbing
guide further comprises a guide body, having a plurality of guide
body surfaces wherein a plurality of square shaped recesses is
formed on one of the plurality of guide body surfaces.
6. A seatbelt apparatus according to claim 3, wherein the tongue
further comprises: a revolving shaft set across a tongue body; a
through hole for rotatably supporting the webbing guide; a lock bar
supported by the webbing guide so as to be capable of relative
rotation; a pair of guide shafts for rotatably supporting the lock
bar; and a bar spring mounted to the mold and the lock bar for
urging the lock bar constantly in one direction.
7. A seatbelt apparatus according to claim 3, wherein a first gap
is defined between a portion of the webbing guide and a portion of
the mold and a second gap is defined between a corner of a lock
body of the lock bar and a portion of the mold, wherein the first
gap and second gap are larger than the thickness of a seatbelt
wherein when the seatbelt passes through the first gap and is
guided by the webbing guide and then passes through the second gap,
the seatbelt tongue slides smoothly with respect to the
seatbelt.
8. A seatbelt tongue according to claim 6, wherein when a force
larger than a predetermined magnitude is applied to the webbing
guide, the webbing guide rotates counterclockwise against a moment
generated by a urging force of the bar spring, the pair of guide
shafts move linearly along a plurality of guide grooves of the mold
while the lock bar rotates clockwise about the pair of guide
shafts, wherein the seatbelt is caught between a corner of the lock
body and the portion of the mold and is locked.
9. A seat belt tongue configured to be slidably supported by a
seatbelt webbing and configured to engage with a buckle,
comprising: a plate covered by a mold; and a webbing guide for
preventing the seatbelt webbing from moving in a direction when a
predetermined force is applied to the seatbelt, the webbing guide
including a lock bar configured so that the webbing is secured
between the lock bar and the mold when the force is applied.
10. A seatbelt tongue according to claim 9, wherein the plate is
formed of a substantially T-shaped metallic plate having a
laterally extending portion and a vertically extending portion
extending vertically from a center of the laterally extending
portion, wherein the laterally extending portion is formed with a
first square opening extending in the lateral direction and the
vertically extending portion is formed with a second square opening
extending in the vertical direction adapted so that a latch member
of the buckle engages the second square opening; and a first and
second side wall extend at a first and second end of the laterally
extending portion, wherein the first and second side walls are each
formed with at least one hole of the same size and at least one
recessed groove of the same size.
11. A seatbelt tongue according to claim 10, wherein the webbing
guide further comprises a guide body, having a plurality of guide
body surfaces wherein a plurality of square shaped recesses is
formed on one of the plurality of guide body surfaces.
12. A seatbelt tongue according to claim 10, wherein the tongue
further comprises: a revolving shaft set across a tongue body; a
through hole for rotatably supporting the webbing guide; a lock bar
supported by the webbing guide so as to be capable of relative
rotation; a pair of guide shafts for rotatably supporting the lock
bar; and a bar spring mounted to the mold and the lock bar for
urging the lock bar constantly in one direction.
13. A seatbelt tongue according to claim 12, wherein a first gap is
defined between a portion of the webbing guide and a portion of the
mold and a second gap is defined between a corner of a lock body of
the lock bar and a portion of the mold, wherein the first gap and
second gap are larger than the thickness of a seatbelt wherein when
the seatbelt passes through the first gap and is guided by the
webbing guide and then passes through the second gap, the seatbelt
tongue slides smoothly with respect to the seatbelt.
14. A seatbelt tongue according to claim 13, wherein when a force
larger than a predetermined magnitude is applied to the webbing
guide, the webbing guide rotates counterclockwise against a moment
generated by a urging force of the bar spring, the pair of guide
shafts move linearly along a plurality of guide grooves of the mold
while the lock bar rotates clockwise about the pair of guide
shafts, wherein a seatbelt is caught between a corner of the lock
body and the portion of the mold and is locked.
Description
BACKGROUND
[0001] The present invention relates to a seatbelt apparatus
mounted on a vehicle such as an automotive vehicle for constraining
and protecting a passenger by a seatbelt and to a seatbelt
apparatus provided with two pretensioners.
[0002] A seatbelt apparatus provided on a vehicle seat of the
automotive vehicle or the like prevents the passenger from jumping
out from the seat of the passenger by constraining the passenger
with the seatbelt in case of emergency such as vehicle collision
where a significant deceleration is applied to the vehicle, thereby
protecting the passenger.
[0003] In the related art, as one of the seatbelt apparatus in the
related art, for example, there is a three-point type seatbelt
apparatus as shown in FIG. 9. In the drawing, reference numeral 1
designates a seatbelt apparatus provided on a vehicle seat 2,
reference numeral 3 designates a seatbelt retractor fixed to a
vehicle body near the vehicle seat 2 for constantly urging a
seatbelt 4 so as to be withdrawably retracted, and locking the
seatbelt 4 from being withdrawn in case of emergency, reference
numeral 5 designates a tongue slidably supported by the seatbelt 4,
reference numeral 6 designates a buckle located on the side of the
vehicle seat 2 and fixed to the vehicle seat 2 or the vehicle body
for being engaged by the tongue 5, and reference numeral 7
designates a belt guide mounted to an upper side of a vehicle side
portion such as a center pillar 8 for guiding the seatbelt 4
withdrawn from the seatbelt retractor 3. A belt anchor portion 4a
at a distal end of the seatbelt 4 withdrawn from the seatbelt
retractor 3 is fixed to the vehicle seat 2 or the vehicle body.
[0004] With the seatbelt apparatus 1 configured as described above,
when the passenger attaches the seatbelt 4, the passenger sits on
the vehicle seat 2, withdraws the seatbelt 4 from the seatbelt
retractor 3, engages the tongue 5 with the buckle 6, and then
releases his/her hand from the tongue 5, whereby the part of the
seatbelt 4 excessively withdrawn is retracted by the seatbelt
retractor 3 and hence a slack of the seatbelt is removed, and the
seatbelt 4 is attached to the passenger. In this case, the seatbelt
4 between the belt guide 7 and the tongue 5 functions as a shoulder
belt 4b for constraining the shoulder and the chest of the
passenger, and the seatbelt 4 between the belt anchor portion 4a
fixed to the vehicle body and the tongue 5 functions as a lap belt
4c for constraining a lap ("lumber") of the passenger.
[0005] Then, in case of emergency such as the vehicle collision of
where a significantly large deceleration is applied to the vehicle,
an emergency locking mechanism of the seatbelt retractor 3 is
activated to lock the seatbelt 4 from being withdrawn and prevent
the forward movement of the passenger by a force of inertia,
whereby the passenger is constrained and protected. In particular,
in the recent years, the pretensioner is provided in the seatbelt
retractor 3, the belt anchor portion 4a, or the buckle or the like
so that the pretensioner is activated in case of occurrence of
emergency and pulls the seatbelt 4 to remove the slack of the
seatbelt 4 quickly so that the forward movement of the passenger is
kept as little as possible, whereby the effects of constraining and
protecting the passenger are improved.
[0006] In the seatbelt apparatus provided with the pretensioner as
described above, there is a seatbelt apparatus in which the
pretensioners are provided in the seatbelt retractor and the belt
anchor portion respectively, so that the pretensioner in the
seatbelt retractor is activated first in case of emergency to
retract the seatbelt by the seatbelt retractor, and then the
pretensioner of the belt anchor portion is activated to pull the
seatbelt and remove the slack of the seatbelt quickly for
constraining the passenger (for example, see Japanese Unexamined
Patent Application Publication No. 2001-287622).
[0007] In the seatbelt apparatus disclosed in Japanese Unexamined
Patent Application Publication No. 2001-287622, since the two
pretensioners are activated under two time frames, even when the
slack of the seatbelt cannot be sufficiently removed by the first
pretensioner, the slack of the seatbelt can be removed by the
second pretensioner, whereby constraint of the passenger is
ensured.
[0008] However, in the seatbelt apparatus disclosed in Japanese
Unexamined Patent Application Publication No. 2001-287622, when a
first pretensioner 9 of the seatbelt retractor 3 is activated and
the seatbelt 4 is retracted by the seatbelt retractor 3 as shown in
FIG. 10(a), both of the shoulder belt 4b and the lap belt 4c are
pulled toward the seatbelt retractor 3 as indicated by an arrow
A.
[0009] Subsequently, a second pretensioner 10 of the belt anchor
portion 4a is activated and hence the seatbelt 4 is pulled toward
the belt anchor portion 4a as shown in FIG. 10(b), both of the lap
belt 4c and the shoulder belt 4b are pulled toward the belt anchor
portion 4a as indicated by an arrow B. Therefore, even though the
lap belt 4c is pulled by the first pretensioner 9 and a slack of
the lap belt 4c is removed, the shoulder belt 4b is pulled with the
lap belt 4c in the opposite direction by the second pretensioner
10, and hence the lap belt 4c is loosened. Therefore, since the lap
belt 4c which functions for constraining the passenger most is
loosened, the effect of constraining the passenger cannot be
sufficiently achieved.
[0010] Therefore, there remains a need to provide a seatbelt
apparatus in which removal of the slack of the lap belt is ensured
even though the two pretensioners are activated under two time
frames, whereby the effects of constraining the passenger are
satisfactorily achieved.
SUMMARY
[0011] According to one embodiment of the invention, a seatbelt
apparatus includes a seatbelt including a shoulder belt for
constraining an upper half body of a passenger and a lap belt for
constraining a lumber of the passenger, a seatbelt retractor for
withdrawably retracting the seatbelt and locking the seatbelt from
being retracted in case of emergency, a belt anchor portion for
fixing a distal end of the seatbelt withdrawn from the seatbelt
retractor to a vehicle body, a tongue slidably supported by the
seatbelt and partitioning between the shoulder belt and the lap
belt, a buckle fixed to the vehicle body and capable of being
engaged by the tongue, a first and a second pretensioner, wherein
each may be provided in at least two devices selected from the
seatbelt retractor, the belt anchor portion and the buckle, wherein
the first and second pretensioners are activated to pull the
seatbelt in case of emergency, the first and second pretensioners
being adapted to be activated under two time frames in such a
manner that the second pretensioner is activated after having
activated the first pretensioner, and a belt one-way movement
preventing mechanism for preventing the shoulder belt from moving
toward the lap belt when the second pretensioner is activated.
[0012] According to another embodiment, a seatbelt apparatus is
configured so that the tongue is a one-way tongue which prevents
the shoulder belt from moving toward the lap belt when a
predetermined pulling force toward the shoulder belt is applied to
the seatbelt and, in this state, a force larger than the
predetermined pulling force is applied to the seatbelt in the
direction toward the lap belt, and the belt one-way movement
preventing mechanism is the one-way tongue.
[0013] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory only, and are not restrictive of the invention as
claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] These and other features, aspects and advantages of the
present invention will become apparent from the following
description, appended claims, and the accompanying exemplary
embodiments shown in the drawings, which are briefly described
below.
[0015] FIG. 1(a) is an explanatory drawing showing a state in which
a pretensioner of a seatbelt retractor is activated according to
one embodiment. FIG. 1(b) is an explanatory drawing showing a state
in which a pretensioner of a belt anchor portion is activated
according to one embodiment.
[0016] FIG. 2 is an exploded perspective view showing an example of
the embodiment of the tongue in the seatbelt apparatus according to
one embodiment.
[0017] FIGS. 3(a)-3(c) show a tongue plate in the example in FIG.
2, in which FIG. 3(a) is a front view, FIG. 3(b) is a right side
view, and FIG. 3(c) is a top view according to one embodiment.
[0018] FIGS. 4(a)-(c) show a webbing guide in the example in FIG.
2, in which FIG. 4(a) is a front view, FIG. 4(b) is a right side
view, and FIG. 4(c) is a bottom view according to one
embodiment.
[0019] FIGS. 5(a)-5(c) show a lock bar in the example in FIG. 2, in
which FIG. 5(a) is a front view, FIG. 5(b) is a right side view,
and FIG. 5(c) is a top view according to one embodiment.
[0020] FIGS. 6(a)-6(d) show a bar spring in the example in FIG. 2,
in which FIG. 6(a) is a front view, FIG. 6(b) is a right side view,
FIG. 6(c) is a top view, and FIG. 6(d) is a perspective view
according to one embodiment.
[0021] FIG. 7 is a perspective view of the tongue shown in the
example in FIG. 2 according to one embodiment.
[0022] FIGS. 8(a)-8(c) illustrate the operation of the tongue shown
in the example in FIG. 2 according to one embodiment of the
invention; FIG. 8(a) is a cross-sectional view showing a state of
the tongue in the stored position when a seatbelt is not attached;
FIG. 8(b) is a cross-sectional view showing the state of the tongue
when the seatbelt is attached and the pretensioner is activated;
and FIG. 8(c) is a cross-sectional view showing the state of the
tongue when the seatbelt is attached and after the pretensioner is
activated.
[0023] FIG. 9 is a perspective view showing a general three-point
type seatbelt apparatus in the related art schematically.
[0024] FIGS. 10(a)-10(b) show an example of the seatbelt apparatus
provided with pretensioners in the related art schematically, in
which FIG. 10(a) is an explanatory drawing showing a state in which
the pretensioner of a seatbelt retractor is activated, and FIG.
10(b) is an explanatory drawing showing a state in which the
pretensioner in the belt anchor portion is activated.
DETAILED DESCRIPTION
[0025] Embodiments of the present invention will be described below
with reference to the accompanying drawings. It should be
understood that the following description is intended to describe
exemplary embodiments of the invention, and not to limit the
invention.
[0026] FIGS. 1(a)-1(b) are schematic drawings of a seatbelt
apparatus according to one embodiment of the invention. FIG. 1(a)
is an explanatory drawing showing a state in which a pretensioner
of a seatbelt retractor is activated, and FIG. 1(b) is an
explanatory drawing showing a state in which a pretensioner of a
belt anchor portion is activated. The same parts as a seatbelt
apparatus 1 in the related art described above shown in FIG. 9 and
FIG. 10 are represented by the same reference numerals.
[0027] As shown in FIG. 1(a), the seatbelt apparatus 1 according to
one embodiment of the invention is configured as the general
three-point type seatbelt apparatus in the related art described
above in such a manner that the a belt anchor portion 4a at one end
of a seatbelt 4 for constraining a passenger is fixed to a vehicle
body, and the other end of the seatbelt 4 is guided by a belt guide
7 mounted to an upper portion of the vehicle body such as a center
pillar, and then withdrawably retracted by a seatbelt retractor 3
fixed to a lower portion of the vehicle body, and a tongue 5
slidably supported by the seatbelt 4 between the belt anchor
portion 4a and the belt guide 7 is engaged with a buckle 6 fixed to
the vehicle body or the like, whereby the passenger seated on a
vehicle seat is constrained.
[0028] The tongue 5 used in the seatbelt apparatus 1 according to
one embodiment of the invention is formed of a one-way tongue. This
one-way tongue is adapted in such a manner that the tongue 5 allows
free passage of the seatbelt 4 in either directions. When a
predetermined pulling force toward the seatbelt retractor 3 is
applied to a shoulder belt 4b and, in this state, a pulling force
which is larger than the predetermined pulling force is applied to
the lap belt 4c in the direction toward the belt anchor portion 4a,
the one-way tongue catches and locks the seatbelt 4 to prevent the
shoulder belt 4b from moving toward a lap belt 4c, and allow the
lap belt 4c to move toward the shoulder belt 4b.
[0029] According to one embodiment of the invention, the seatbelt
apparatus uses a tongue proposed in Japanese Patent Application No.
2004-375760 that the present applicant previously filed as a patent
application.
[0030] FIG. 2 is an exploded perspective view showing the tongue
proposed in Japanese Patent Application No. 2004-375760.
[0031] As shown in FIG. 2, the tongue 5 includes a tongue body 13
having a metallic tongue plate 11 and a tongue mold 12 which covers
the tongue plate 11 partly with resin, a webbing guide 14 provided
on the tongue body 13 so as to be capable of relative rotation, a
revolving shaft 15 set across the tongue body 13 by being fitted
into a pair of mounting holes 13a, 13b of the tongue body 13 and a
through hole 14a of the webbing guide 14 respectively for rotatably
supporting the webbing guide 14, a lock bar 16 supported by the
webbing guide 14 so as to be capable of relative rotation, a pair
of revolving shafts 17, 18 formed of bolts for rotatably supporting
the lock bar 16 by being fitted into a through hole 14b of the
webbing guide 14 and a pair of mounting holes 16a, 16b of the lock
bar 16, and a bar spring 19 mounted respectively to the tongue mold
12 and the lock bar 16 for urging the lock bar 16 constantly in one
direction.
[0032] FIGS. 3(a)-3(c) show the tongue plate 11 according to one
embodiment of the invention. FIG. 3(a) is a front view, FIG. 3(b)
is a right side view, and FIG. 3(c) is a top view.
[0033] As shown in FIGS. 3(a) to 3(c), the tongue plate 11 is
formed of a substantially T-shaped metallic plate having a
laterally extending portion 11a and a vertically extending portion
11b extending integrally and vertically from a center portion of
the laterally extending portion 11a. The laterally extending
portion 11a is formed with a large square opening 11c extending in
the lateral direction, and the vertically extending portion 11b is
formed with a square opening 11d extending in the vertical
direction. The opening 11d in the vertical direction is adapted so
that a latch member of the buckle 6, not shown, engages like
general tongues in the related art. Therefore, the vertically
extending portion 11b is configured as an engaging strip which
engages with the tongue 5. Hereinafter, the vertically extending
portion 11b is also referred to as the engaging strip 11b.
[0034] A pair of side walls 11e, 11f are provided so as to extend
upright at both ends of the laterally extending portion 11a. The
side walls 11e, 11f are formed respectively with holes 11g, 11h of
the same size. The pair of side walls 11e, 11f are provided
respectively with recessed grooves 11i, 11j of the same size. As
shown clearly in FIG. 3(b), one of the recessed groove 11i is
formed into T-shape with a lateral groove 11i opening to an outer
peripheral edge of the side wall 11e and a vertical groove
11i.sub.2 in communication with the lateral groove 11i.sub.1. The
other recessed groove 11j has the same shape as the recessed groove
11i, and is formed into the T-shape with a lateral groove 11j.sub.1
and a vertical groove 11j.sub.2 (Reference numerals 11h, 11j.sub.1,
11j.sub.2 are not shown in the drawing, but correspond to 11g,
11i.sub.1, 11i.sub.2 respectively, and are used for convenience of
explanation).
[0035] As shown in FIG. 2, almost all of the laterally extending
portion 11a of the tongue plate 11 is molded with resin, and then
the tongue mold 12 is formed. In this case, by molding an inner
peripheral surface of the pair of holes 11g, 11h with resin, the
above-described pair of mounting holes 13a, 13b for allowing
fitting of the revolving shaft 15 are formed. Also, by closing a
right end of the recessed groove 11i in FIG. 3(a) and a left end of
the recessed groove 11j in FIG. 3(a) with mold resin respectively
and molding an inner peripheral surface of the pair of recessed
grooves 11i, 11j as shown in FIG. 2, guide grooves 13c, 13d are
formed respectively. One of the guide grooves 13d is formed into
the T-shape with a vertical groove 13d.sub.1 opening upward and a
lateral groove 13d.sub.2 communicating with the lateral groove
13d.sub.1. The other guide groove 13c has the same shape as the
guide groove 13d and is formed into the T-shape with a vertical
groove 13c.sub.1 and a lateral groove 13c.sub.2 communication with
the vertical groove 13c.sub.1. (Reference numeral 13c.sub.2 is not
shown, but corresponds to the reference numeral 13d.sub.2, and is
used for convenience of explanation). Furthermore, by molding an
inner peripheral surface of the opening 11c of the tongue plate 11
with resin, a large square opening 13e is formed on the tongue body
13.
[0036] FIGS. 4(a)-4(c) show the webbing guide 14 according to one
embodiment of the invention. FIG. 4(a) is a front view, FIG. 4(b)
is a right side view, and FIG. 4(c) is a bottom view.
[0037] As shown in FIGS. 4(a) to 4(c), the webbing guide 14 is
formed into a substantially square shape in lateral cross-section,
and is provided with a relatively long guide body 14c having four
corners rounded into R portions having a large diameter. Four
surfaces 14c.sub.1, 14c.sub.2, 14c.sub.3, and 14c.sub.4
corresponding to the four sides of the square guide body 14c
respectively are formed into curved surfaces which swell slightly
outward. At least one side of these four sides may be formed as a
linear plate.
[0038] On one surface 14c.sub.1 of the guide body 14c facing
downward in FIG. 2 is formed with a predetermined number (seven in
the example shown in the drawing) of square shaped recesses 14d.
The above-described through hole 14a is provided in the guide body
14c so as to penetrate therethrough in the longitudinal direction.
Another surface 14c.sub.4 of the guide body 14c is formed with a
mounting member 14e integrally along the longitudinal direction of
the guide body 14c. Then, the above-described through hole 14b is
formed on the mounting member 14e so as to penetrate in the
longitudinal direction.
[0039] A boundary including a corner between the surface 14c.sub.1
of the guide body 14c and the surface 14c.sub.2 continuing from the
surface 14c.sub.1 and facing upward corresponds to a webbing guide
portion 14f for guiding the seatbelt 4 on the input side of the
seatbelt 4. Furthermore, the surface 14c.sub.4 of the guide body
14c functions as a stopper as described later.
[0040] The revolving shaft 15 for rotatably supporting the webbing
guide 14 on the tongue body 13 is adapted to function also as a
strength retaining member which can support a pulling force of a
large magnitude which is applied to the seatbelt 4 in case of
emergency.
[0041] FIGS. 5(a)-5(c) shows the lock bar 16 according to one
embodiment of the invention. FIG. 5(a) is a front view, FIG. 5(b)
is a right side view, and FIG. 5(c) is a top view.
[0042] As shown in FIGS. 5(a) to 5(c), the lock bar 16 is provided
with a lock body 16c of substantially square shape in a lateral
cross-section. The lock body 16c is provided at both ends thereof
with guide shafts 16d, 16e respectively. The guide shafts 16d, 16e
are fitted to the guide grooves 13c, 13d of the tongue body 13 so
as to be capable of moving, whereby guiding the lock body 16c. The
lock body 16c is integrally provided at both ends thereof with
mounting members 16f, 16g having an arched cross section so as to
extend upright at a predetermined distance. The distance between
the pair of mounting members 16f, 16g are set to a length which
allows entry of the mounting member 14e of the webbing guide 14
between the mounting members 16f, 16g. The above-described pair of
mounting holes 16a, 16b are formed on the mounting members 16f,
16g, respectively. The lock body 16c is formed at both ends thereof
with mounting holes 16h, 16i which are circular in
cross-section.
[0043] FIGS. 6(a) to 6(d) show the bar spring 19 according to one
embodiment of the invention. FIG. 6(a) is a front view, FIG. 6(b)
is a right side view, FIG. 6(c) is a top view, and FIG. 6(d) is a
perspective view.
[0044] As shown in FIGS. 6(a) to 6(d), the bar spring 19 is formed
of a resilient wire member, and is formed into a relatively
complicated shape in laterally symmetry shown in FIGS. 6(a) and
6(c). In other words, the bar spring 19 includes, in sequence from
a right side of a first portion 19a at a center toward a right end,
a second portion 19b bent in the vertical direction at a right
angle, a third portion 19c bent from the second portion 19b at a
right angle with respect to both of the first and second portions
19a, 19b, a fourth portion 19d bent from the third portion 19c
toward the second portion 19b so as to extend in parallel with the
second portion 19b and at right angle with respect to the third
portion 19c, a fifth portion 19e bent from the fourth portion 19d
toward an opposite side from the first portion 19a so as to extend
in parallel with the first portion 19a and at a right angle with
respect to the fourth portion 19d, and a sixth portion 19f bent
from the fifth portion 19e toward an opposite side from the first
portion 19a at a right angle with respect to the fifth portion 19e.
The bar spring 19 also includes, on a left side of the first
portion 19a at the center thereof, a second portion 19g, a third
portion 19h, a fourth portion 19i, a fifth portion 19j, and a sixth
portion 19k corresponding to the respective portions on the right
side.
[0045] The bar spring 19 is adapted to be mounted in such a manner
that the first portion 19a at the center thereof is fitted into and
supported by a spring supporting portion 12a which is constituted
of a recessed groove of the tongue mold 12 shown in FIG. 2, and
left and right sixth portions 19k, 19f thereof are fitted to the
mounting holes 16h, 16i of the lock bar 16 respectively.
[0046] The tongue 5 of this example in such a structure is
assembled, according to one embodiment of the invention, as
described below. The mounting member 14e of the webbing guide 14 is
positioned between the mounting members 16f, 16g of the lock bar
16, the revolving shafts 17, 18 are fitted into the mounting holes
16a, 16b of the lock bar 16 respectively and the through hole 14b
of the webbing guide 14, and the lock bar 16 is mounted to the
mounting member 14e on the output side of the webbing guide 14 so
as to be capable of relative rotation. The respective sixth
portions 19f, 19k of the bar spring 19 are fitted into the mounting
holes 16h, 16i of the lock bar 16, and the bar spring 19 is mounted
to the lock bar 16.
[0047] Then, as shown in FIG. 7, the webbing guide 14 is placed
between left and right side walls 12b, 12c of the tongue mold 12 in
such a manner that the webbing guide portion 14f faces toward the
engaging strip 11b, and the revolving shaft 15 is fitted into the
mounting holes 13a, 13b of the tongue body 13 and the through hole
14a of the webbing guide 14, whereby the webbing guide 14 is
mounted to the tongue body 13 so as to be capable of relative
rotation. Also, the left and right guide shafts 16d, 16e of the
lock bar 16 are passed through the vertical grooves 13c.sub.1,
13d.sub.1 and then slidably fitted to the lateral groves 13c.sub.2,
13d.sub.2 of the guide grooves 13c, 13d, respectively.
[0048] Finally, the first portion 19a at the center of the bar
spring 19 is fitted to the recessed groove of the spring supporting
portion 12a of the tongue mold 12. At this time, the guide shafts
16d, 16e of the lock bar 16 are pressed leftward in FIG. 8(a) by an
urging force of the bar spring 19 and moved leftward along the
lateral grooves 13c.sub.2, 13d.sub.2 of the guide groove 13c, 13d
of the tongue mold 12. Simultaneously, since a clockwise moment
about the revolving shaft 15 is applied to the webbing guide 14 and
the lock bar 16 by the urging force of the bar spring 19, the
webbing guide 14 and the lock bar 16 rotate clockwise about the
revolving shaft 15. In this case, since the position of the
revolving shaft 15 is fixed, the guide shafts 16d, 16e gradually
approach the revolving shaft 15. Therefore, as shown in FIG. 8(a),
the webbing guide 14 and the lock bar 16 rotate with a bending
movement with respect to each other so that the centers of the
revolving shafts 17, 18 are located at positions lower than a
straight line connecting between the center of the revolving shaft
15 and the centers of the guide shafts 16d, 16e.
[0049] Then, the lock bar 16 comes into abutment with a stopper
constituted by the one surface 14c.sub.4 of the webbing guide 14 so
that further bending movement with respect to the webbing guide 14
is prevented, and is kept in a state of being bent at substantially
a right angle. When the guide shafts 16d, 16e further move leftward
and come into contact with one end of each lateral groove
13c.sub.2, 13d.sub.2 of the guide grooves 13c, 13d, further
leftward movement of the guide shafts 16d, 16e are prevented,
whereby the tongue 5 is assembled in a state in which the webbing
guide 14 and the lock bar 16 are maintained in initial positions as
shown in FIG. 8(a).
[0050] In this manner, in a state in which the webbing guide 14 and
the lock bar 16 are maintained in the initial positions shown in
FIG. 8(a), a gap .alpha. is defined between the webbing guide
portion 14f of the webbing guide 14 and a portion 12d of the tongue
mold 12 opposing to the webbing guide portion 14f, and a gap .beta.
is defined between a corner of the lock body 16c of the lock bar 16
and a portion 12e of the tongue mold 12 opposing this corner. These
gaps .alpha., .beta. are set to maximum values significantly larger
than the thickness of the seatbelt 4 in a state shown in FIG. 8(a).
Therefore, when the tongue 5 is supported by the seatbelt 4 so that
the seatbelt 4 passes through the gap .alpha. and is guided by the
webbing guide 14, and then passes through the gap .beta., the
tongue 5 slides with respect to the seatbelt 4 smoothly without
little resistance. In addition, since the seatbelt 4 guided by the
webbing guide 14 through the opening 13e of the tongue body 13 does
not interfere with the tongue mold 12 of the tongue body 13, the
tongue 5 slides further smoothly with respect to the seatbelt 4.
When the gap .alpha. is too large, reversal of the seatbelt 4 may
be resulted easily, and hence the gap .alpha. is set to an extent
that does not cause the reversal of the seatbelt 4.
[0051] When a force larger than a predetermined magnitude which
causes a counterclockwise moment about the revolving shaft 15 is
applied to the webbing guide 14, the webbing guide 14 rotates
counterclockwise against the moment generated by the urging force
of the bar spring 19. Then, by the rotation of the webbing guide
14, the guide shafts 16d, 16e move linearly along the guide grooves
13c, 13d of the tongue mold 12 while the lock bar 16 rotates
clockwise about the guide shafts 16d, 16e. By the clockwise
rotation and the linear movement of the lock bar 16, the seatbelt 4
is caught between the corner of the lock body 16c and the portion
12e of the tongue mold 12 and is locked.
[0052] In other words, the two pieces of the webbing guide 14 and
the lock bar 16 constitute a lap belt extension preventing
mechanism for preventing extension of the lap belt 4c by locking
the seatbelt 4 in case of emergency. In this case, by the rotation
and the linear movement of the lock bar 16, even when the amount of
rotation of the lock bar 16 is relatively reduced while increasing
the amount of rotation of the webbing guide 14, the sufficient
amount of the linear movement of the lock bar 16 is secured.
[0053] Subsequently, the operation of the tongue 5 according to one
embodiment of the invention will be described. When the seatbelt 4
is not attached as shown in FIG. 8(a), the seatbelt 4 is retracted
by the seatbelt retractor 3, not shown, and the tongue 5 assumes a
stored state. In the stored state of the tongue 5, the webbing
guide 14 and the lock bar 16 are retained in the initial positions
shown in FIG. 8(a) by the urging force of the bar spring 19 and the
stopper (the first surface 14c.sub.4 of the guide body 14c) and the
both gaps .alpha., .beta. are set to the maximum value as described
above. Therefore, the tongue 5 is smoothly slidable with respect to
the seatbelt 4.
[0054] In order to attach the seatbelt 4, the passenger withdraws
the tongue 5 from the stored position and inserts the engaging
strip 11b of the tongue 5 into the buckle 6 on the opposite side.
At this time, since the seatbelt 4 is withdrawn from the seatbelt
retractor 3, and the webbing guide 14 and the lock bar 16 do not
rotate and are maintained at the initial positions, the tongue 5
slides smoothly with respect to the seatbelt 4. When the passenger
engages the tongue 5 with the buckle 6, and then releases the
tongue 5, the excessively withdrawn seatbelt 4 is retracted by the
seatbelt retractor 3, and hence the seatbelt 4 fits the passenger
without giving a feeling of pressure, and the tongue 5 assumes the
state shown in FIG. 8(b). In the state shown in FIG. 8(b), since a
retracting force of the seatbelt retractor 3 is applied to the
seatbelt 4, the seatbelt 4 is maintained in the state of being
pulled lightly toward the shoulder (SHO side) of the passenger.
Therefore, the webbing guide 14 and the lock bar 16 are maintained
in the initial positions. In this state, the seatbelt 4 is in
abutment with the webbing guide portion 14f, and is also in
abutment with the mounting member 14e of the webbing guide 14.
[0055] In case of emergency such as vehicle collision or the like
where a significantly large deceleration is applied to a vehicle,
when the pretensioner, not shown, provided in the seatbelt
retractor 3 is activated, the seatbelt 4 is quickly retracted by
the seatbelt retractor 3, and the seatbelt 4 is pulled toward the
SHO side further strongly. Therefore, the webbing guide 14 and the
lock bar 16 are still maintained in the initial positions.
[0056] When the operation of the pretensioner is ended, the
seatbelt 4 is pulled toward the lumber of the passenger (LAP side)
strongly by a force of inertia toward the front at the lumber (LAP)
of the passenger. Since the pulling force of the seatbelt 4 toward
the LAP side acts on the webbing guide portion 14f and the mounting
member 14e of the webbing guide 14 and a counterclockwise large
moment about the revolving shaft 15 is applied to the webbing guide
14, the webbing guide 14 rotates counterclockwise about the
revolving shaft 15. Simultaneously, the guide shafts 16d, 16e move
linearly from one end to the other end (toward the right in FIG.
8(b)) along the lateral grooves 13c.sub.2, 13d.sub.2 of the guide
grooves 13c, 13d of the tongue mold 12 while the lock bar 16
rotates clockwise about the guide shafts 16d, 16e.
[0057] Due to the counterclockwise rotation of the webbing guide 14
and the clockwise rotation and the linear movement of the lock bar
16, the corner of the lock body 16c of the lock bar 16 approaches
the portion 12e of the tongue mold 12 and the gap P is reduced.
Accordingly, as shown in FIG. 8(c), the seatbelt 4 is caught
between the corner of the lock body 16c and the portion 12e of the
tongue mold 12. In this case, since the sufficient amount of linear
movement is secured even when the amount of rotation is small
because of the rotation and the linear movement of the lock bar 16,
the significantly large force is generated to catch the seatbelt
4.
[0058] In addition, in a state in which the seatbelt 4 is caught
between the corner of the lock body 16c and the portion 12e of the
tongue mold 12, the centers of the revolving shafts 17, 18 that
connect the webbing guide 14 and the lock bar 16 are located at
positions slightly upper than the straight line connecting the
center of the revolving shaft 15 and the centers of the guide
shafts 16d, 16e. Therefore, the urging force of the bar spring 19
urges the webbing guide 14 and the lock bar 16 about the revolving
shaft 15 so as to rotate counterclockwise. In other words, the
force to catch the seatbelt 4 by the corner of the lock body 16c
and the portion 12e of the tongue mold 12 is increased to a further
large force by the pulling force of the seatbelt 4 toward the LAP
side and the urging force of the bar spring 19. Therefore, the
seatbelt 4 is firmly caught by the corner of the lock body 16c and
the portion 12e of the tongue mold 12 and hence locking of the
seatbelt 4 by the lock bar 16 is reliably achieved. Therefore,
sliding movement of the seatbelt 4 between the corner of the lock
body 16c and the portion 12e of the tongue mold 12, and hence
extension of the seatbelt 4 is prevented, whereby constraint of the
passenger by the seatbelt 4 is ensured.
[0059] Other structures and other operations of the seatbelt
apparatus 1 according to one embodiment of the invention are the
same as the example shown in FIG. 9 and FIG. 10 described
above.
[0060] In the seatbelt apparatus 1 according to one embodiment of
the invention, when a first pretensioner 9 of the seatbelt
retractor 3 is activated and the seatbelt 4 is retracted by the
seatbelt retractor 3, both of the shoulder belt 4b and the lap belt
4c are pulled toward the seatbelt retractor 3 as shown by an arrow
in FIG. 1(a). Then, a second pretensioner 10 of the belt anchor
portion 4a is activated, and the seatbelt 4 is pulled toward the
belt anchor portion 4a as shown in FIG. 1(b). At this time, since
the tongue 5 is constructed as the above-described one-way tongue,
when the second pretensioner 10 is activated in a state in which
both of the shoulder belt 4b and the lap belt 4c are pulled toward
the seatbelt retractor 3 by a predetermined pulling force by the
operation of the first pretensioner 9, and hence the lap belt 4c is
pulled toward the belt anchor portion 4a by a pulling force larger
than the predetermined pulling force as shown by an arrow B, the
tongue 5 catches and locks the seatbelt 4. Accordingly, when the
lap belt 4c is pulled toward the belt anchor portion 4a, the
shoulder belt 4b does not move toward the lap belt 4c through the
tongue 5. Therefore, removal of a slack of the lap belt 4c is
ensured, and hence the lumber of the passenger is securely
constrained.
[0061] According to the seatbelt apparatus 1 according to one
embodiment of the invention, when the two pretensioners are
activated under two time frames in such a manner that the
pretensioner 9 of the seatbelt retractor 3 is activated first and
then the pretensioner 10 of the belt anchor portion 4a is
activated, the tongue 5 prevents the shoulder belt 4b from moving
toward the lap belt 4c, removal of the slack of the lap belt 4c is
ensured. Accordingly, the lumber of the passenger by the lap belt
4c can be constrained firmly, and hence the effects of constraining
the passenger can be sufficiently achieved.
[0062] Since the tongue 5 which is composed of the one-way tongue
is used as the belt one-way movement preventing mechanism, it is
not necessary to provide specific parts as the belt one-way
movement preventing mechanism, and hence the number of parts can be
reduced, and the structure can be simplified and, in addition, the
seatbelt apparatus 1 can be manufactured at a low cost.
[0063] In the example described above, the two pretensioners 9, 10
are provided in the seatbelt retractor 3 and the belt anchor
portion 4a. However, in the present invention, the two
pretensioners 9, 10 can be provided in any two of the seatbelt
retractor 3, the belt anchor portion 4a, and the buckle 6. In this
case, if there is a probability that the shoulder belt 4b moves
toward the lap belt 4c when the second pretensioner is activated,
the movement of the shoulder belt 4b toward the lap belt 4c can be
prevented by the belt one-way movement preventing mechanism. Even
when there is a probability that the lap belt 4c moves toward the
shoulder belt 4b when the second pretensioner is activated, since
it is the direction to remove the slack of the lap belt 4c, the
belt one-way movement preventing mechanism can be adapted so as not
to prevent the movement of the lap belt 4c toward the shoulder belt
4b.
[0064] Although the tongue in the above-described Japanese Patent
Application No. 2004-375760 is used as the one-way tongue which
constitutes the tongue 5, it is not limited thereto, and other
types of one-way tongue can be used as long as it prevents the
movement of the shoulder belt 4b toward the lap belt 4c through the
tongue 5 when the pretensioner of the second step is activated and
hence the lap belt 4c is pulled. It is also possible to constitute
the belt one-way movement preventing mechanism with a suitable
structure other than the tongue.
[0065] Several advantages are realized from the above-described
invention. The tongue of the present invention used for the
seatbelt apparatus mounted in the vehicle such as the automotive
vehicle for constraining and protecting the passenger by the
seatbelt, and can be suitably used as the tongue which is slidably
supported by the seatbelt and engages with the buckle.
[0066] According to one embodiment, in the seatbelt apparatus of
the present invention, when there is a probability that the
shoulder belt moves toward the lap belt when the second
pretensioner is activated subsequently, the belt one-way movement
preventing mechanism prevents the shoulder belt from moving toward
the lap belt. Therefore, removal of the slack of the lap belt is
ensured. Accordingly, the lumber of the passenger can be firmly
constrained by the lap belt, and the effects of constraining the
passenger are satisfactorily achieved.
[0067] In particular, according to another embodiment of the
invention, since the one-way tongue is used as the belt one-way
movement preventing mechanism, it is not necessary to provide
specific parts as the belt one-way movement preventing mechanism,
and hence the number of parts can be reduced, and the structure can
be simplified. In addition, the seatbelt apparatus can be
manufactured at a lower cost.
[0068] Priority Application 2005-110462, filed Apr. 7, 2005
including the specification, drawings, claims and abstract, is
incorporated herein by reference in its entirety.
[0069] The foregoing description of a preferred embodiment of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed, and modifications and
variations are possible in light of the above teaching or may be
acquired from practice of the invention. The embodiment was chosen
and described in order to explain the principles of the invention
and as a practical application to enable one skilled in the art to
utilize the invention in various embodiments and with various
modification are suited to the particular use contemplated. It is
intended that the scope of the invention be defined by the claims
appended hereto and their equivalents.
* * * * *