Note: Descriptions are shown in the official language in which they were submitted.
RELEASE FOR SAFETY BELT TENSION-RELIEVIN~ APPARATUS
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Background of the Invention
This invention relates to a vehicle safety belt system
adapted to restrain an occupant in his seat and to a safety belt,
tension-relieving apparatus adapted to relieve tension on a
safety belt when in use by an occupant of the vehicle. More
particularly, this invention relates to an improved release means
for releasing a known tension-relieving apparatus.
An example of a known tension-relieving apparatus for
which the release means of the present invention may be used is
a mechanical tension-relieving apparatus disclosed in U.S. Patent
Nos. 3,851,836 and 3,869l098, both entitled "Vehicle Occupant ~ --
Restraint Belt Retractor" and both filed August 23, 1973 in the
name of R. G. Sprecher.
Summary of_the Invention
In accordance with the present invention, there is
provided, in a vehicle safety belt system adapted to restrain
an occupant in a vehicle seat, the safety belt system including
a safety belt, a retractor having a rewind mechanism biased to
rewind the safety belt on a reel of the retractor, a tension-
relieving apparatus for relieving tension on the safety belt,
the tension applied by the rewind mechanism of the retractor,
the improvement of a release means for the tension-relieving
apparatus, the release means comprising:
a sensing means disposed in the vehicle for operating
the release means;
a tension-relieving locking means disposed on the
retractor, the tension-relieving locking means having a ready
position wherein the locking means may be operated by the
tension-relieving apparatus and an unlocking position wherein
the rewind mechanism is allowed to wind the safety belt into
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the retractor, the sensing means causing the tension-relieving
locking means to move to its unlocking position thereby deactivating
the tension-relieving apparatus and allowing the rewind mechanism
to wind the safety belt into the retractor;
an actuating means mounted on the retractor adjacent
to the locking means, mechanically coupled to a portion of the
tension-relieving locking means and electrically coupled to the
sensing means, the actuating means moving the tension-relieving
locking means to its unlocking position thereby allowing the
rewind mechanism of the retractor to operate under; and
a biasing means biasing the tension-relieving locking
means in its ready position, wherein the locking means may be oper-
ated by the tension-relieving apparatus to block the rewind mechanism
and relieve tension on the safety belt.
The sensing means is preferably located in a door jamb
of the vehicle and moves the tension relieving means to its lock
position when the door is closed.
The tension-relieving locking means preferably includes:
a tension-relieving ratchet wheel connected to the reel of the
retractor; and a tension-relieving locking pawl for locking the
tension-relieving ratchet wheel. The locking means may also
include linkage means connecting the locking pawl to the actuating
means. The actuating means may be a solenoid having a plunger
coupled directly or indirectly to the tension-relieving locking
pawl or an electro-magnet coupled to the tension-relieving locking
pawl. Three embodiments are described hereinafter.
Description of the Drawings
Fig. 1 is a simplified illustration of the improvement
of the present invention installed in a vehicle.
Fig. 2 is a side elevational view of a portion of a first
embodiment of the present invention showing the locking means and
the actuating means.
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Fig. 3 is a simplified schematic illustration of the
first embodiment of the present invention.
Fig. 4 is a side elevational view of a portion of a
second embodiment of the present invention showing the locking
means and the actuating means.
Fig. 5 is a side elevational view of a portion of a
third embodiment of the present invention showing the locking
means and the actuating means.
Fig~ 6 is a simplified electrical schematic of a portion
of the third embodiment shown in Fig. 5.
Detailed Description
Referring to Fig. 1, the improvement of the present -
invention is for use in a vehicle safety belt system 2 adapted
to restrain an occupant 4 in the vehicle seat 6. The safety belt
system 2 includes a safety belt, including a shoulder belt 8, a lap
belt, or both; a retractor 10 having a rewind mechanism (not shown)
biased to rewind the shoulder belt 8 on a reel of the retractor 10;
and a tension-relieving apparatus for relieving tension on the
safety belt, such as the shoulder belt 3. The tension is applied
20 by the rewind mechanism of the retractor 10. The improvement of
the present invention is a release means for the tension-relieving
apparatus. Referring to Figs. 1 - 5, the release means includes:
a sensing means 12 (FigO 1), a tension-relieving locking means 14
(Figs. 2-5), an actuating means 16 (Figs. 2-5), and a biasing means
18 (Figs~ 2-5).
; The sensing means 12 may be a switch disposed in a door-
jam 11 of a door 13 of a vehicle 15 for mechanically sensing a con-
dition when the door 13 of the vehicle 15 is opened and when the door
13 is closed. The tension~relieving locking means 14 is disposed on
30 the retractor 10, either within the retractor housing or on the
outside of the retractor housing. The tension-relieving locking ~ -
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means 14 has a ready posltion in which the locking means 14 is in
` a position to be operated by a known tension-relieving appara-tus. The
known tension-relieving apparatus moves the locking means 14 into a
locking position wherein the locking means 14 opposes or counteracts
the force applied by the rewind spring (not shown) and thereby re-
lieves tension on the shoulder belt 8. The known tension-relieving
apparatus may, for example, be the apparatus described in U.S.
Patent 3,351,836 or the apparatus described in U.S Patent 3,869,098.
The locking means 14 also has an unlocking position wherein the
- 10 rewind mechanism is allowed to wind the shoulder belt 8 into the
retractor 10.
The sensing means 12 causes the tension-relieving locking
means 14 to move to its unlocking position when the door 13 is open,
thereby deactivating the tension-relieving apparatus and allowing
the rewind mechanism to wind the shoulder belt 8 into the retractor
10. rrhe actuating means 16 is mounted on the retractor 10 adjacent
to the tension-relieving loc~ing means 14. The actuating means 16
is mechanically coupled to a portion of the tension-relieving lock-
ing means 14 and electrically coupled to the sensing means 12. The
actuating means 16 moves the tension-relieving locking means 14 to
its unlocking position, thereby releasing the tension-relieving ap-
paratus and allowing the rewind mechanism of the retractor 10 to
operate when the door is opened. rrhe biasing means 1~ biases the
tension-relieving locking means 14 in its ready position, in which
the locking means 14 may be operated by the tension-relieving ap-
paratus to block, that is, oppose or counteract the rewind mech-
anism and relieve tension on the shoulder belt ~ when the door 13
is closed.
The locking means 14 includes: a tension-relieving - ;
30 ratchet wheel 20 connected to the reel 22 of the retractor 10;
and a tension-relieving locking pawl 24 for engaging and locking
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the tension-relieving ratchet wheel 20, thereby blocking or de- ;
activating the rewind mechanism. The tension-relieving ratchet wheel
20 and the tension-relieving locking pawl 24 are separate from and
should not be confused with a different ratchet wheel and locking
pawl often used in safety belt retractors for locking the retractor
during emergency conditions, such as when the vehicle is subjected
to sudden deceleration, acceleration or roll-over or when unwinding
of the safety belt is suddenly accelerated. The rewind mechanism
(not shown) typically is a spiral spring installed in the retractor
10. The rewind mechanism is well known in the art. An example of
such a rewind mechanism is disclosed in U.S. Patent Nos. 3,610,361
(reference numeral 210); 3,741,496 (reference numeral 13); and
3,797,603 (reference numeral 64).
In a first embodiment, illustrated in Figs. 2 and 3, the
actuating means 16 may be a solenoid 16a having a plunger 26 connec-
ted to a tension-relieving locking pawl 24a. The locking means 14
includes the ratchet wheel 20 and the locking pawl 24a. Fig. 2
shows the solenoid 16a in its deactivated position with the plunger
26 pushed partially out of the solenoid 16a. The biasing means 18
may be a spiral spring 18a arranged around the plunger 26 which
biases the plunger 26 in its extended position from the solenoid 16a.
The rewind mechanism (not shown) rewinds the seat belt in a counter-
clockwise direction as indicated by arrow A in Fig. 2. The rewind
direction is the direction in which the reel 22 is wound in order
to wind the shoulder belt 8 into the retractor 10. The ratchet
- teeth of the tension-relieving ratchet wheel 20 are arranged so
that when the ratchet wheel 20 is wound in the rewind direction,
the ratchet teeth may be engaged by the tension-relieving locking
pawl 24. Tension-relieving locking pawl 24a may be attached to the
outer end of the plunger 26, that is, the end of the plunger 26 op-
posite from the solenoid 16a. The tension-relieving locking pawl 24a
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may have a curved, hook-like configuration, which has been shaped
to facilitate engagement of a ratchet tooth of the ratchet wheel 20.
In a second embodiment illustrated in Fig. 4, the ten-
sion-relieving locking means 14 may further include a linkage means
arranged between the plunger 26 and the tension-relieving lockin~
pawl 24b, in addition to the ratchet wheel 20 and the locking pawl
24b. The linkage means includes: an L-shaped plunger bracket 27
and a pawl bracket 28. The plunger bracket 27 has a first leg 30
and a second leg 32. The pawl bracket 28 also has a first leg 34
and a second leg 36. The legs 30 and 32 of the plunger bracket 27
may be arranged approximately perpendicular to one another. The
plunger bracket 27 pivots about a first pivot point 38. The legs
34 and 36 of the pawl bracket 28 may be arranged at an angle of
less than 90 with reference to one another and preferably at an
angle in the range of approximately 30 to 45. The pawl bracket
28 pivots about a second pivot point 40 The locking pawl 24b is
connected to the first leg 34 of the pawl bracket 28 adjacent to
; the opposite end from second pivot point 40. The locking pawl
; 24b pivots about a third pivot point 42 located on the first leg34 of pawl bracket 28. The second leg 32 of the plunger bracket
26 is positioned adjacent to the second leg 36 of the pawl
bracket 28. A biasing means in the form of a torsion spring 18b
biases the pawl 24b in the ready position in which the pawl 24b
- is ready to engage the ratchet wheel 20. Thus, the second
embodiment includes three separate pivot points: a first pivot
point 38 for the plunyer bracket 26; a second pivot point 40
for the pawl bracket 28; and a third pivot point 42 for the
pawl 24b itself. The linkage means allows the actuating means
16 to be mounted in various positions with reference to the
retractor. The pawl 24b has a first arm 25 which engages the
ratchet wheel 20 and a second arm which is acted upon by the
torsion spring 18b. The first arm 25 is arranged approximately
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perpendicular to the second arm 23.
Fig. ~ shows the solenoid 16b in its deactivated position
with the plunger 26 pushed partially out of the solenoid 16. The
plunger 26 presses the leg 32 of the plunger bracket 26 into con-
tact and engagement with the leg 36 of the pawl bracket 28, which
presses the pawl 24b into a position in which it is ready for
engagement with the ratchet wheel 20. The solenoid 16b is in its
deactivated position when the door 13 is closed. When the door 13
is opened, the solenoid 16b is activated, causing the plunger 26
to be withdrawn into the solenoid 16b, moving leg 32 of bracket 26
away from leg 34 of pawl bracket 28. The force from the rewind
mechanism (not shown) exerted through the tension-relieving ratchet
wheel 20 overcomes the force of the torsion spring 18b and pushes
the locking pawl 24 away from the ratchet wheel 20 and into the
unlocking position of the locking means 14.
In the operation of the first and second embodiments
: (Figs. 1-4), when the occupant 4 enters the vehicle and closes the
door 13, the sensing means 12 closes, cleactivating the actuating
means 16, allowing the biasing means 18 to press the tension-
relieving locking pawl 24 into a ready position so that it can be
moved into engagement with the tension-relieving ratchet wheel 20.
The locking pawl 24 is not actually ~oved into engagement with the
tension-relieving ratchet wheel 20 by the release means of the
present invention, but is merely placed in a position where it can
be placed in engagement with ratchet wheel 20 by a known tension-
relieving apparatus such as that disclosed in U.S. Patent No.
3,851,836 or U.S. Patent application No. 390,781.
,~ Referring to Figs. 1 -4, the sensing means 12 may be
connected to the actuating means 16 (Figs. 2 and 4) by an electri-
cal wire 27 (Fig. 3). Referring to Fig. 3, the electric wire may
be the same wire which is conventionally used for operating a
courtesy light in the vehicle, such as a dome light 29 in the
interior ceiling of the vehicle. Furthermore, the sensing means
12 may be a switch similar to swi-tches conventionally used in the
door-jam of the door 13 of the vehicle for operating the dome light
28. Indeed, the sensing means 12 may be the same switch which is
conventionally used for operating the dome light 29. The use of a
switch in the door-jam of the vehicle provides a simple, efficient
means for actuating the tension-relieving mechanism. Such means is
simple because it reduces the number of moving parts and allows the
use of a commercially available switcho
In a third embodiment, illustrated in Fig. 5, the actua-
ting means 16 may be an electromagnet 16c. The locking means 14 may
further include a pawl bracket 28, similar to the pawl bracket 28
in the second embodiment, in addition to a ratchet wheel 20 and a
locking pawl 24b, similar to the locking pawl 24b in the second
embodiment~ The third embodiment does not use a plunger bracket.
Referring to Fig. 5, the electromagnet 16c is shown in its energized
position in which it attracts and holds the leg 36 of the pawl
bracket 28.
In operation, when the electromagnet 16c is in its energized
position, the pawl 24b is held in a ready position in which it can
be moved by the known tension~relieving apparatus into engagement
with the ratchet wheel 20, relieving tension on the shoulder belt.
When the electromagnet 16c is de~energized, it no longer exerts a force~
on leg 34, allowing leg 34 to fall away. When leg 34 falls away
from the electromagnet 16c, the pawl 24b falls away from the tension-
relieving ratchet wheel 20 as a result of the force exerted by the ~ -
rewind mechanism (not shown) tran~mitted through the ratchet wheel
20 which pushes the pawl 24b away from the ratchet wheel 20.
Referring to Fig. 6, when the door 13 is closed and the
ignition 46 is turned, power is provided to energize the electro-
magnet 16c. When the door 13 is open or the ignition 46 is turned
off, the electromagnet 16 is de-energi7ed.
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All three embodiments overcome the problem of allowing
the shoulder belt 8 to hang loosely when the occupant 4 leaves the
vehicle. As a result of the release means of the present invention,
the shoulder belt 8 does not become caught in the door 13 of the
vehicle. The term "connected" as used in the description of this
invention means a direct attachment without any intermediate com-
ponents. The term "coupled" as used in the description of this
invention means either a direct attachment or an indirect attach-
ment with intermediate components.
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