KR101398992B1 - Apparatus for preventing pretwist of seatbelt load limiter and overshooitng of seatbelt pretensioner - Google Patents

Abstract

The present invention relates to a seat belt pretensioner, and more particularly, to a device for reducing a pre-twist of a seat belt load limiter and an overshoot of a pretensioner.
The present invention relates to a torsionally-torsionally torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally- A pretensioner follower coupled to the free end of the torsion shaft for positively rotating the spool through the torsion shaft, a pretensioner drive for positively rotating the pretensioner follower, a fixed portion fixed to the spool, And a wire for preventing a relative rotation of the pretensioner follower and the spool when the pretensioner follower is rotated forward. The present invention also provides an overshoot preventing device for a pretensioner and pretensioner of a seat belt load limiter.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overshoot preventing device for a seat belt load limiter and an overshoot prevention device for a pretensioner,

The present invention relates to a seat belt pretensioner, and more particularly, to a device for reducing a pre-twist of a seat belt load limiter and an overshoot of a pretensioner.

The present invention minimizes the clearance between the seat belt and the driver, and between the driver and the seat back to maximize protection of the occupant, The present invention relates to a pretensioner (PRE-TENSIONER) for reverse rotation of a seat belt spool capable of maintaining stability without restoring it.

The seat belt is made of a high-tension fiber material and has a buckle to be detachable. The spool that winds the seat belt is fixed to the side wall of the vehicle body to increase the convenience for the user and freely unwinds or winds the seat belt. The spool is rotatable in the frame, and the spool can be restored to its original position by using spring elasticity or the like.

However, since the driver's upper body moves forward when the vehicle is stopped due to a frontal collision or the like, there is a problem that the seat belt collides with the window or the steering wheel in the actual accident, contrary to the original purpose of restricting the driver to the seat there was. This is because there is a gap between the upper body of the driver and the seat belt and the back of the seat immediately after the collision. Therefore, in the automobile industry, a pretensioner (PRETENSIONER), which is a tension device for rotating the spool in the reverse direction and momentarily eliminating the above-mentioned gap, is needed. In addition, a rod limiter (energy absorbing device) is required to release the belt slowly in the direction in which the passenger is moved, thereby restricting the high load applied to the chest to a predetermined load or less. In recent years, when the tension of the belt is increased due to the load applied to the belt by the forward movement of the passenger's body after the operation of the pretensioner, the load momentarily drops due to the operation of the locking device, Techniques for solving the above problems have been developed and commercialized by changing the position of the pretensioner to the same side as the locking device in order to prevent injury of the passenger due to load increase.

1 is a view showing an example of a conventional safety belt pretensioner disclosed in Korean Patent Application No. 10-2008-0052832. The pretensioner is operated to wind the webbing on the spool 11 and restrain the occupant to the designated position. When a tensile force greater than a reference value set on the webbing is applied, the spool 11 rotates in the direction of pulling out the webbing, The spool 11 engaged with the torsion shaft 12 is coupled to the base lock 14 by the shear pin 13 and the base lock 14 and the torsion shaft 12 are engaged with the spline The base lock 14 is coupled to a ratchet tooth 16 formed on the outer periphery of the base lock 14 to prevent rotation thereof. The tensile force applied to the webbing is formed on one side of the spool 11 by applying a rotational force to the spool 11 and the shear pin 13 coupled to the base lock hole 17 of the base lock 14 is sequentially broken The webbing is pulled out.

The shear pins 13 coupled to the base lock holes 17 are formed in such a manner that the base lock holes 17 and the shear pins 13 are first brought into contact with each other at intervals in contact with the base lock hole 17, .

A plurality of base lock holes 17 formed in the base lock 14 are formed radially from the center of rotation. The base lock holes 17 have the same width but different lengths. The base lock holes 17 are formed on one side of the spool 11 The spacing between the shear pin 13 and the base lock hole 17 when assembled with the shear pin 13 formed at regular intervals is assembled differently and the limit of the load limiter by changing the breaking strength of the shear pin 13 The load can be easily changed.

That is, the share pin is broken at a load lower than the limit load of the load limiter.

The rotation of the torsion shaft 12 fixed to the spool 11 and the base lock 14 is limited by the locking device so that the torsion shaft 12 is rotated by the tensile force of the webbing applied to the spool 11, Absorbs impact applied to the body of the occupant by absorbing tensile force applied to the webbing by causing a permanent deformation in which the shape of the torsion shaft 12 is twisted while a torsional stress acts.

The sleeve 18 is inserted into the end of the torsion shaft 12 so that one side is engaged with the base lock 14 and a sleeve hole 19 corresponding to the base lock hole 17 is formed radially at the center, The size of the hole 19 is the same as that of the shear pin 13 and the shear pin 13 penetrates the base lock hole 17 and is engaged with the sleeve hole 19.

Thus, the phosphor input of the pretensioner is transmitted to the entire sleeve hole 19 to rotate the spool 11. [

At this time, the share pin 13 is not completely broken.

A protruding portion is formed on one side of the sleeve 18 and a knurling portion 20 is formed on the outer circumferential surface of the protruding portion so as to be engaged with the clutch mechanism of the pretensioner.

The torsion shaft 12 and the base lock 14 and the sleeve 18 are separated from each other in the axial direction while the shear pin 13 is broken when the load limiter is operated.

A thread is formed on the shaft portion of the torsion shaft 12 and the nut 22 is fastened and fixed so as to prevent the base lock 14 and the sleeve 18 from separating from the torsion shaft 12. [

However, when the pretensioner is changed to the same position as the locking part, the load limiter device such as the torsion shaft is operated at an unexpected time during the operation of the pretensioner, thereby causing a reduction in the restraint force of the seat belt.

The pre-tensioner located on the same side as the conventional spring part directly rotates the spool winding the belt while the pretensioner located on the locking part side rotates the spool through the torsion shaft. Therefore, when the pretensioner is operated, The torque that is transmitted to the spool at the initial stage becomes small, and consequently, the force for winding the belt is lowered, so that the restraining force of the seat belt is lowered.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus capable of preventing unintended rotation of a load limiter device during operation of a pretensioner.

The present invention also aims to prevent unintended increase in load at the beginning of operation of the load limiter device.

The present invention relates to a torsionally-torsionally torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally-torsionally- A pretensioner follower coupled to the free end of the torsion shaft for positively rotating the spool through the torsion shaft, a pretensioner drive for positively rotating the pretensioner follower, a fixed portion fixed to the spool, And a wire for preventing a relative rotation of the pretensioner follower and the spool when the pretensioner follower is rotated forward. The present invention also provides an overshoot preventing device for a pretensioner and pretensioner of a seat belt load limiter.

According to another embodiment of the present invention, the resistance portion of the wire is disposed along the circumferential direction of the spool, and includes a first region of an arc shape, a second region of an arc shape having a larger radius than the first region, The spool includes a ring-shaped first groove in which a first region of the wire resistance portion is received, and a second groove in which a second region of the wire resistance portion is received. The forward portion of the forward rotation of the pretensioner follower portion Wherein the counterclockwise end of the second region is supported by the counterclockwise end of the second groove to prevent relative rotation of the pretensioner follower and the spool, And a shooting prevention device.

In another embodiment of the present invention, the wire causes deformation when the spool is reversely rotated, and provides a predetermined resistance force during relative rotation of the pretensioner follower and the spool. The pre-twist of the seat belt load limiter and the over- And a shooting prevention device.

Further, according to another example of the present invention, the pretensioner follower includes a ring-shaped first accommodating portion in which a first region of the wire deforming portion is accommodated, a ring accommodating portion accommodating a second region of the wire deforming portion, And a third accommodating portion for connecting the first accommodating portion and the second accommodating portion. The deformation of the wire accommodated in the second accommodating portion during relative rotation of the spool and the pretensioner follower by the spool reverse rotation And the second seat is deformed by being moved to the first accommodating portion. The present invention also provides an overshoot prevention device for a pretensioner and a pretensioner.

According to another aspect of the present invention, there is provided an overshoot prevention device for a pretensioner and pretensioner of a seat belt load limiter, wherein the pretensioner follower includes a base which contacts the spool and receives the wire, to provide.

Another aspect of the present invention provides a pretensioner for a seat belt load limiter and an overshoot prevention device for a pretensioner, wherein a locking part for restricting the backward rotation of the pretensioner follower is attached to one side of the pretensioner follower.

The pre-twist of the seat belt load limiter and the overshoot prevention device of the pretensioner provided by the present invention are such that the torsion shaft is deformed due to the rotational speed difference between the torsion shaft and the pinion at the initial stage of operation of the pretensioner, .

In addition, the present invention provides a safety belt device in which a tensioner device is placed on the same side as a locking part, in which a pre-twist of a seat belt load limiter and an overshoot prevention device of a pretensioner are provided, So that excessive load can be applied to the belt at the beginning of the operation of the load limiter to prevent injury to the passenger.

1 is a view showing an example of a conventional safety belt pretensioner,
FIG. 2 is an exploded perspective view of a seatbelt apparatus including an overshoot prevention device of a pretensioner and a pretensioner of a seatbelt load limiter according to an embodiment of the present invention; FIG.
FIGS. 3 and 4 illustrate an apparatus for preventing overshoot of a pretensioner and a pretensioner of a seat belt load limiter according to an embodiment of the present invention; FIG.
FIG. 5 and FIG. 6 are views of part of an overshoot preventing device of a pretensioner and a pretensioner of a seat belt load limiter according to an embodiment of the present invention, as viewed from a side of a spring device.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

2 is an exploded perspective view of an angene belt device according to an embodiment of the present invention. A seat belt apparatus according to an embodiment of the present invention includes a frame 100 to which various devices are attached and a seat belt webbing is received and a pinion 310 which is a follower portion by pushing the rack 220 downward when an impact is received A pretensioner driving part 200 which is operated to rotate the seat belt on the spool 300 by rotating the spool 300, a spool 300 on which the seat belt webbing is wound, a locking part 400 for preventing reverse rotation of the pinion 310, And a spring part 500 for rewinding. Hereinafter, the forward rotation direction means a direction in which the seat belt webbing is wound around the spool 300, and is a counterclockwise rotation. The reverse rotation direction means a direction in which the seat belt webbing is released from the spool 300, and is a clockwise rotation.

 The spool 300 is positioned inside the frame 100 and the spring part 500 is used to pull the seatbelt webbing from the spool 300 in a normal situation and rewind it to the side of the frame 100 Respectively. On the other side of the frame 100, a pretensioner 200 is provided to increase the restraining force of the seat belt to protect the passenger when a strand is applied due to collision of the vehicle or the like.

The pretensioner driving unit 200 includes a gas generating mechanism 210 that receives a predetermined shock or transmits an expansion force of the gas by exploding the gas at the time of rapid deceleration of the vehicle, (Not shown).

As the rack 220 is protruded, that is, when the rack 220 is linearly moved, the pinion 310 and the pinion base 340 corresponding to the pretensioner follower rotate. The pinion 310 and the pinion base 340, which are the pretensioner follower units, may be integrally formed, or may be formed as separate parts and coupled together. A pinion base (340) is positioned at one end of the pinion (310), and a locking part (400) is coupled to the other end.

In the embodiment of the present invention shown in the drawings, the pretensioner driving part 200 and the follower part adopt a rack and pinion type, but any configuration may be employed as long as it has a known configuration of the pretensioner.

Inside the spool 300, a torsion shaft 320 is provided which can serve as a load limiter for restricting the load applied to the webbing of the seat belt. One end of the torsion shaft 320 is fixed to the spool 300, and the other end is fixed to the pinion base 340 described above. One end of the torsion shaft 320 fixed to the spool 300 is located on the side where the spring part 500 is installed and the other end fixed to the pinion base 340 is the pretensioner 200 and the locking part 400 Located on the installed side.

2, when the gas is generated in the gas generating mechanism 210 and the rack 220 linearly moves downward due to the expansion force, the pinion 310 and the pinion base 340 are rotated in the counterclockwise direction . The torsion shaft 320 fixed to the pinion base 340 also rotates together with the pinion base 340. The spool 300 is also rotated counterclockwise by the rotation of the torsion shaft 320, .

At this time, the tensile force of the seat belt webbing is increased due to the inertia force of the passenger moving toward the front of the seat, and the spool 300, the torsion shaft 320, and the pinion base 340 and the pinion 310 can rotate. To prevent this, a locking part 400 is provided on one side of the pinion 310. The locking part 400 has a lock base 410 formed with a ratchet groove in engagement with the pretensioner 200 and a ratchet groove formed in the lock base 410 so as to be smaller in diameter than the ratchet groove formed in the lock base 410, A ratchet wheel 430 that is only allowed to move in one direction by a ratchet groove formed in the lock base 410, And a lock cover 440 which is coupled to the connection portion 410 and covers the connection portion 420 and the ratchet wheel 430. 2, the locking part 400 is allowed to move the rack 220 downward due to the expansion of the gas and to rotate the pinion 310 counterclockwise, but the pinion 310, It is not allowed to rotate in the clockwise direction.

If the seat belt webbing is not released because the reverse rotation of the pinion 310 is not permitted, the seat belt webbing may cause the passenger to receive an excessive load and suffer injuries. In order to prevent this, the pinion 310 does not rotate, but the torsional deformation of the torsion shaft 320 occurs so that the spool 300 is rotated. That is, when a load equal to or greater than a certain level is applied to the seatbelt webbing, a torsional deformation occurs in the torsional shaft 320 in a clockwise direction, and the spool 300 rotates to unroll the seatbelt webbing. By adjusting the degree to which the torsion deformation of the torsion shaft 320 occurs, the maximum load that the passenger can receive can be adjusted. That is, the torsion shaft 320 serves as a load limiter.

However, as the pinion 310 rotates rapidly in the counterclockwise direction, the rotational force of the torsion shaft 320 can not rotate the spool 300 (the pinion base 340 and the spool 300 rotate relative to each other) A counterclockwise torsional deformation occurs in the torsion shaft 320 and the rotational force of the spool 300 is lowered at the initial stage of the operation of the pretensioner 200 so that the seat belt webbing can not be sufficiently wound and the passenger binding force of the seat belt may be deteriorated. A wire 330 is provided between the spool 300 and the pinion base 340 to provide a resistance against the relative rotation of the pinion base 340 and the spool 300. [ The spool 300 does not rotate and only the pinion base 340 rotates or prevents the relative rotation between the spool 300 and the pinion base 340 due to the rotation of the pinion base 340 faster than the spool 300 . When the pinion base 340 rotates relative to the pinion base 340 and the spool 300 due to the reverse rotation of the spool 300 while the pinion base 340 is stopped, the wire 330 is deformed to permit relative rotation A predetermined resistance can be given. The wire 330 is preferably made of steel having a predetermined strength so as to have a resistance force while being deformed.

FIG. 3 and FIG. 4 are views showing an overshoot preventing device of a pretensioner and a pretensioner of a seat belt load limiter according to an embodiment of the present invention.

The pre-twist of the seat belt load limiter and the overshoot prevention device of the pretensioner include the spool 300, the pinion 310, the torsion shaft 320, the wire 330, and the pinion base 340. A torsion shaft 320 is installed inside the spool 300 and one end of the torsion shaft 320 is fixed to one end of the spool 300 (one end on the spring part 500 side). The other end of the torsion shaft 320 is not fixed to the spool 300, and when the torsion shaft 320 is twisted, the other end is rotatable with respect to the spool 300. The other end is fixed to the pinion base 340. When the torsion shaft 320 serving as a load limiter rotates the pinion 310 in the normal rotation (counterclockwise rotation), only the torsion shaft 320 rotates while the spool 300 is stopped by inertia, A wire 330 is provided between the spool 300 and the pinion base 340 to prevent it from happening.

The wire 330 is inserted and fixed in the spool 300 and the resistance portions 332, 333 and 334 are positioned between the spool 300 and the pinion base 340. The wire 330 has a relatively small arc-shaped first region 332, a relatively large arc-shaped second region 333, and a second region 333 connecting the first region 332 and the second region 333 And a third area 334. The spool 300 includes a ring-shaped first groove 301 capable of receiving the first area 332 of the wire 330 and a second groove 302 extending in the radial direction from the first groove 301 by a predetermined length, And a second groove 302 capable of receiving the second region 333.

The wire 330 is supported by the counterclockwise end of the second region 333 in the counterclockwise direction of the second groove 302 when the pinion 310 is rotated forward. Therefore, the spool 300 rotates only the pinion base 340 without rotating, or the pinion base 340 rotates faster than the spool 300, so that the spool 300 and the pinion base 340 relative to each other. Accordingly, the torsion shaft 320 is not twisted, and the pinion base 340 and the spool 300 rotate together without rotating relative to each other, so that the seat belt webbing is wound up properly on the spool 300 at the beginning, Can be prevented.

Further, after the seat belt webbing is sufficiently wound on the spool 300, when the tension of the seat belt webbing is higher than a predetermined level, the spool 300 is rotated in the counterclockwise direction to loosen the seat belt webbing to some extent. Since the pinion 310 is locked by the locking device 400, the pinion 310 does not rotate in the reverse direction. Therefore, the spool 300 rotates reversely while the torsion shaft 320 is twisted. The spool 300 can rotate only when a torsion force is applied so that the torsion shaft 320 can be twisted. The load applied to the seat belt continues to increase until the torsion shaft 320 begins to be tilted. When the torsion shaft 320 is twisted, the maximum load is applied at the moment of torsion. When the torsion shaft 320 is twisted, The load is lowered. If the torsional strength of the torsion shaft 320, which is a load limiter, is high, a significant impact is applied to the passenger. Therefore, instead of lowering the torsional strength of the torsion shaft 320, the wire 330 provides a resistance force when the torsion shaft 320 is twisted, so that the torsion shaft 320 is twisted abruptly, It is possible to prevent falling.

FIGS. 5 and 6 are views showing part of an overshoot prevention device of a pretensioner and a pretensioner of a seat belt load limiter according to an embodiment of the present invention, as viewed from the side of a spring device. FIG. 5 shows a state before the spool 300 is reversely rotated, and FIG. 6 shows a state after the spool 300 is reversely rotated.

The end of the torsion shaft 320 on the side of the locking device 400 (see FIG. 1) is fixed to the pinion base 340 and the end of the torsion shaft 320 on the side of the spring device 500 (see FIG. 1) As shown in FIG. 5 and 6, the illustration of the spool 300 (see FIG. 4) is omitted. When the spool 300 is reversely rotated (counterclockwise in FIGS. 5 and 6), the torsion shaft 320 is also reversed while being twisted. One end of the wire 330 is fixed to the spool 300 and the other end of the wire 330 is inserted between the spool 300 and the torsion base 340. When the spool 300 is rotated in the reverse direction, It is deformed and rotated.

The torsion base 340 includes a ring-shaped first receiving portion 341 and a ring-shaped second receiving portion 342 that is larger than the first receiving portion 341. The torsion base 340 includes a first receiving portion 341, And a third accommodating portion 343 connecting the first accommodating portion 342 and the second accommodating portion 342. The first accommodating portion 341 and the second accommodating portion 342 are partitioned by a ring-shaped protruded partition wall 344 formed between the first accommodating portion 341 and the second accommodating portion 342, And the groove 343 formed in the first receiving portion 344 becomes the third receiving portion 343. [

The first region 332 of the resistive portions 332 333 and 334 of the wire 330 is connected to the first receiving portion 341 and the second region 333 is connected to the first receiving portion 341 before the spool 300 reversely rotates. 2 accommodating portion 342, and the third region 334 is accommodated in the third accommodating portion 343. The wire 330 fixed to the spool 300 also rotates in the reverse direction as the spool 300 rotates in the reverse direction and gradually deforms from the third area 334 and the second area 333 of the wire 330 And the third region 334 are accommodated in the first accommodating portion 341. It is possible to prevent a sudden reverse rotation of the spool 300 even if the torsional strength of the torsion base 340 is low due to the resistance force of the wire 330 when the wire 330 rotates and is accommodated in the first accommodating portion 341. [

The pre-twist of the seat belt load limiter and the overshoot prevention device of the pretensioner according to the present invention include a wire between the spool and the pinion base in the seat belt device in which the pretensioner is disposed on the locking part side, It is possible to prevent the load limiter from causing the twist deformation at the beginning of the operation of the pretensioner apparatus, without significantly changing the configuration of the entire seat belt apparatus. Also, since the wire provides resistance, the torsional strength of the load limiter can be lowered, and the pretensioner can be operated in an excessive manner to prevent excessive load from being applied to the passenger.

Claims (6)

A spool for forwardly winding the seat belt webbing, releasing the seatbelt webbing in the reverse direction;
A torsion shaft penetrating the spool, one end fixed to the spool and the other end being able to twist with a free end not fixed to the spool;
A pretensioner follower coupled to the free end of the torsion shaft and for positively rotating the spool through the torsion shaft;
A pretensioner driving unit for forward-rotating the pretensioner follower unit; And
And a wire for preventing relative rotation between the pretensioner follower and the spool when the pretensioner follower is rotated forward, wherein the wire is wound around the pretensioner follower and the spool,
The wire causes a deformation when the spool is reversely rotated and provides a predetermined resistance force during relative rotation of the pretensioner follower and the spool. The pretensioner follower includes a ring-shaped first receiving portion for receiving a first region of the wire deformation portion, A ring-shaped second receiving portion accommodating a second region of the wire deforming portion and having a larger diameter than the first accommodating portion, and a third accommodating portion connecting the first accommodating portion and the second accommodating portion,
Wherein the deformation of the wire accommodated in the second accommodating portion is changed and transferred to the first accommodating portion during relative rotation of the spool and the pretensioner follower due to the reverse rotation of the spool, Prevention device. The method according to claim 1,
The resistance portion of the wire is disposed along the circumferential direction of the spool and includes a first region of an arc shape, a second region of an arc shape having a larger radius than the first region, and a third region connecting the first region and the second region and,
The spool has a ring-shaped first groove in which a first region of the wire resistance portion is accommodated, and a second groove in which a second region of the wire resistance portion is accommodated,
Wherein the counterclockwise end of the second region is supported by the counterclockwise end of the second groove during normal rotation of the pretensioner follower to prevent relative rotation of the pretensioner follower and the spool Prevention of overshoot of pre-twist and pretensioner. delete delete 3. The method according to claim 1 or 2,
Wherein the pretensioner follower includes a base which abuts against the spool and which receives the wire, and a bite engageable with the pretensioner driving portion. 3. The method according to claim 1 or 2,
Characterized in that a locking part for restricting the backward rotation of the pretensioner follower is attached to one side of the pretensioner follower, and a pretensioner for preventing overshoot of the pretensioner.

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