KR20170011730A

KR20170011730A - Pretensioner

Info

Publication number: KR20170011730A
Application number: KR1020150104897A
Authority: KR
Inventors: 문찬기; 이학구
Original assignee: 아우토리브 디벨롭먼트 아베
Priority date: 2015-07-24
Filing date: 2015-07-24
Publication date: 2017-02-02

Abstract

A pretensioner is provided. The pretensioner includes a cable having an end connected to the buckle; A piston connected to the other end of the cable for transferring the cable; A clamp provided at one side of the piston and clamped to the other end of the cable; A cylinder movably receiving the piston and the clamp; A noise preventing member connected to one end of the clamp facing the piston to prevent noise when the cylinder is in contact with the cylinder; A gas generator for supplying gas to the cylinder to move the piston; A chamber for receiving gas supplied from a gas generator; And a housing having a guide path for transportably supporting an intermediate portion of the cable

Description

Pretensioner {PRETENSIONER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pretensioner for pulling a seat belt in a vehicle decelerating state.

Background Art [0002] Generally, a seat belt for restraining an occupant is provided on a seat for a vehicle to prevent an occupant from projecting forward due to an inertial force when a sudden stop or collision of the vehicle occurs. Such a seat belt device has an emergency locking lock retractor that locks the spindle of the seat belt only when a shock of the vehicle occurs and does not restrict the operation of the occupant during normal operation . This automatic lock retractor locks the spindle in a very short time when a deceleration of a predetermined value or more is detected, thereby preventing the seat belt from being pulled out.

However, if the seat belt is restrained by loosening the spindle by locking the spindle like the above-described automatic locking retractor, the seat belt is continuously drawn out to some extent even if the springs are locked. Even if the seat belt is not loosely wound, the seat belt is continuously drawn until the spindle is locked after a predetermined deceleration or higher is detected.

A pretensioner for pulling a seat belt buckle when a predetermined deceleration is detected is known as a device for canceling the insertion of the seat belt to some extent due to such relaxation of the seat belt or a time lag from locking of the spindle.

In such a pretensioner apparatus, a clamp for supporting the cable in a cylinder so as to be capable of transporting the cylinder may collide with the inner wall of the cylinder during the operation of the pretensioner, and noise may be generated.

United States Patent Application Publication No. US2007 / 0029775 U.S. Patent No. US2011 / 022178

SUMMARY OF THE INVENTION An object of the present invention is to provide a pretensioner that eliminates noise caused by a collision of a clamp, which fixes a cable to a distal end side of a piston, due to vibration of a vehicle in a state of being mounted on a pretensioner vehicle.

According to an aspect of the present invention, there is provided a cable having an end connected to a seat belt buckle; A piston connected to the other end of the cable to transfer the cable; A clamp provided at one side of the piston and clamped to the other end of the cable; A cylinder movably receiving the piston and the clamp; A noise preventing member connected to one end of the clamp facing the piston to prevent noise when the cylinder is in contact with the cylinder; A gas generator for supplying gas to the cylinder to move the piston; And a housing in which a chamber accommodating gas supplied from the gas generator and a guide path for transportably supporting an intermediate portion of the cable are formed.

The noise preventing member may be formed of a plastic material.

The noise preventing member may be formed of separate water, and may be coupled to the outer periphery of the clamp by an inserting method, or an insert may be injected onto the clamp.

A part of the gas supplied from the gas generator is passed through the piston and the cable, and the clamp can be fixed to the outer circumference of the cable by interference fit.

The noise preventing member may be configured such that a gas hole communicating with the gap is formed to leak the gas generated from the gas generator to the clamp side.

A protrusion is formed at the tip of the noise preventing member and a seat groove in which the tip of the noise preventing member is seated is formed at the rear end of the piston.

According to the pretensioner of the present invention, the noise preventing member is provided at one end of the clamp for fixing the cable, so that noise is generated by colliding the clamp against the inner wall of the cylinder during operation of the pretensioner.

1 is a partial perspective view showing a configuration of a pretensioner according to the present invention.
2 is a side sectional view showing a configuration of the pretensioner of the present invention.
3 is an enlarged view of the III display portion.
4 is a perspective view showing a state in which the clamp and the noise preventing member of the present invention are separated.
5 is another perspective view showing a state in which the clamp and the noise preventing member of the present invention are separated.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know.

1 is a partial perspective view showing a configuration of a pretensioner according to the present invention.

Referring to Fig. 1, the pretensioner 1 is a device for pulling the seat belt buckle 3 when a sudden stop of the vehicle or an impact such as a collision occurs.

The pretensioner 1 is fixed to a cable 5 connected to the seat belt buckle 3, for example, directly to the vehicle body or through a bracket or the like and penetrates the cable 5 and guides a part of the cable 5 to bend A housing 10 having a guide portion 11 and a cylinder 9 supported on the other side of the housing 10.

2 is a side sectional view showing a configuration of the pretensioner of the present invention.

2, one end of the cable 5 is supported by the seat belt buckle 3, and the other end of the cable 5 is supported by the piston 30. The piston (30) is slidably received in the cylinder (9). A clamp (40) for fixing the other end of the cable (5) is connected to the tip of the piston (30).

A noise preventing member 50 is provided between the piston 30 and the clamp 40. A bowling 21 and a plurality of balls 23 are provided between the outer periphery of the piston 30 and the inner peripheral wall of the cylinder 9. [ Respectively. The movement of the piston 30 to the one end side (the A direction side) is permitted and the movement of the piston 30 to the other end side (the B direction side) is blocked by the bowling 21 and the ball 23. [

The housing 10 includes a chamber 13 to which a gas is supplied and a guide path 15 for transportably supporting a middle portion of the cable 5. [

The gas generator 70 is inserted into the insertion portion 17 protruded on one side of the housing 10 to supply gas to the chamber 13.

On the guide path 15 on the rear end side of the chamber 13, the packing 60 is press-fitted to prevent the gas supplied from the gas generator 70 from leaking in the direction A. The packing (60) includes a through hole (61) through which the cable (5) passes.

3 is an enlarged view of the III display portion.

Referring to FIG. 3, a piston 30 formed by forging a metal is accommodated in the cylinder 9. The piston 30 includes a piston body 31 through which the cable 5 passes and an annular groove 33 formed in the piston body 31 is provided with a piston body 31, An O-ring 81 for sealing between the O-rings 81 is disposed. A clamp 40 for fixing the other end of the cable 5 is connected to the tip end of the piston main body 31.

The piston main body portion 31 includes a tapered portion 35 that gradually increases in a direction (direction B) toward the clamp 40. A flange portion 37 having an outer diameter substantially equal to the inner diameter of the cylinder 9 is formed at the end portion of the piston main body portion 31 in the direction of arrow A. A plurality of balls (23) are disposed between the tapered portion (35) and the inner wall surface of the cylinder (9). As a result, the movement of the piston 30 to one end side (the B direction side) is permitted and the movement of the piston 30 to the other end side (the A direction side) is blocked.

The plurality of balls 23 are disposed between the inner circumferential surface of the cylinder 9 and the tapered portion 35 of the piston 30. The diameter of the ball 23 is slightly smaller than the maximum clearance between the inner peripheral surface of the cylinder 9 and the outer peripheral surface of the tapered portion 35. [ The ball 23 is seated between the inner peripheral surface of the cylinder 9 and the outer peripheral surface of the tapered portion 35 when the piston 30 is about to move toward the buckle 3. [

In this way, the movement of the piston 30 in the direction B is permitted and the movement in the direction A is restricted.

In the annular groove 18 of the housing 10, an O-ring 83 sealing between the housing 10 and the inner wall surface of the cylinder 9 is disposed.

A noise preventing member 50 made of a plastic material is provided between the piston main body 31 and the clamp 40.

A protrusion 53 is formed at one end of the clamp 41 facing the piston main body 31 and a seat groove 39 at which the protrusion 53 is fitted is formed at the tip of the clamp 41.

A predetermined gap G is formed between the inner periphery of the piston main body 31 and the outer periphery of the cable 5 so that a part of the gas leaks in the direction of the arrow A. [

The piston 30 may be formed of a heat-resistant material thermally cured so as to withstand the high temperature heat of the gas generated from the gas generator 70.

The cable (5) is fixed by the press fitting method so that the clamp (40) fixes the cable (5) to the distal end side of the piston (30). Therefore, the clamp 41 is formed of a relatively soft material as compared with the piston 30, so that the press fitting can be easily performed.

The noise preventing member 50 is formed of a soft plastic material that is softer than the clamp 40 so that the clamp 40 flows while the piston 30 moves in the direction of the arrow B by the high pressure gas and flows into the inner peripheral wall of the cylinder 9 If it hits, it acts as buffer. Therefore, generation of noise can be prevented. The noise preventing member 50 is fitted to one end of the clamp 40 and is configured so that the cable 5 penetrates. The noise preventing member 50 is formed with the gas hole 51 in which the gas flows in the direction of arrow B.

The gas hole 51 is configured to communicate with the gap G between the piston 30 and the inner surface of the cylinder 9 so that the gas generated from the gas generator 70 flows through the gap between the piston 30 and the cable 5 (G) and the gas holes (53) of the noise preventing member (50).

FIGS. 4 and 5 are perspective views showing a state in which the clamp and the noise preventing member of the present invention are separated. FIG.

4 and 5, the noise preventing member 50 is fitted to one end of the clamp 40 in a fitting manner. In another embodiment, the noise preventing member 50 may be insert-injected into one end of the clamp 40. [ The noise preventing member (50) includes a gas hole (51) through which the gas passes. The gas hole 51 is constituted by a method in which a plurality of ribs 55 that come into contact with the outer periphery of the clamp 40 are disposed at a predetermined interval along the circumferential direction of the clamp 40. The plurality of ribs 55 protrude in the radial direction from the inner circumferential surface of the noise preventing member 50 and are fitted to the outer periphery of the clamp 40.

Next, the operation of the pretensioner of the present invention will be described.

When a detection device such as an acceleration sensor detects the rapid deceleration state of the vehicle, for example, in a state where the occupant is seated on the seat and the seat belt of the seat belt device is mounted, a control device (not shown) The ignition device of FIG. In the gas generator (70), the ignition device ignites the gas generating agent, and the gas generating agent burns the chamber (13) as a combustion chamber to generate a large amount of gas.

The tip of the tapered portion 35 of the piston 30 and the O-ring 81 are slid along the inner circumferential surface of the cylinder 9 by the pressure of the gas so as to move in the direction of the arrow B in the cylinder 9. The cable 5 with the other end fixedly attached to the piston 30 slides along the guide path 15 and the packing 60 and pulls the buckle 3 connected to one end thereof.

That is, the piston 30 is moved a predetermined distance in the direction of the arrow B and the buckle 3 connected to the piston 30 through the cable 5 is pulled by a predetermined length to tighten the seat belt (not shown) Is reduced.

At this time, the clearance G between the piston body 31 and the inner circumferential surface of the cylinder 9 and the area of the gas hole 51 of the noise preventing member 50 are set such that the area of the piston body 31 The piston 30 is prevented from moving in the direction of the arrow B in the cylinder 9 by the gas pressure generated from the gas generator 70. That is, the gap G and the gas hole 51 do not interfere with the normal operation of the pretensioner 10.

On the other hand, when the operation or detection of the acceleration sensor (not shown) is delayed or the control device malfunctions, if the gas generator 70 is ignited after the load is applied to the belt by the inertial movement of the passenger due to rapid deceleration The gas in the chamber 15 is supplied to the chamber 13 in a state where the piston 30 is prevented from moving in the direction of the arrow B of the cylinder 9, do.

At this time, the gas leaks in the direction of the arrow B in the cylinder 9 through the gap G and the gas hole 51.

The gas in the chamber 13 is discharged in the direction of the arrow A in the cylinder 9 before the seal between the chambers 13 is leaked out from the sealed guide path 15 by the packing 60, A larger amount of gas is discharged in the direction of the arrow B in the cylinder 9 than the gas leaking to the outside in the combustion chamber 15 to prevent a safety accident.

When the gas generated from the gas generator 70 is suddenly applied to the piston 30 during the operation of the pretensioner 1, the clamp 40 which is in contact with the piston 30 is separated or flows from the piston 30, And may collide against the inner circumferential surface of the runner 9. At this time, the noise can be prevented by absorbing the impact by the noise preventing member 50 fitted in the clamp 40.

Although the present invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the present invention is not limited thereto but is limited by the following claims.

Accordingly, those skilled in the art will appreciate that various modifications and changes may be made thereto without departing from the spirit of the following claims.

1: pretensioner 3: buckle
5: Cable 10: Housing
13: chamber 15: guide path
30: Piston 40: Clamp
50: noise preventing member 39: seat groove
51: gas hole 53: protrusion

Claims

A cable having an end connected to the buckle;
A piston connected to the other end of the cable to transfer the cable;
A clamp provided at one side of the piston and clamped to the other end of the cable;
A cylinder movably receiving the piston and the clamp;
A noise preventing member connected to one end of the clamp facing the piston to prevent noise when the cylinder is in contact with the cylinder;
A gas generator for supplying gas to the cylinder to move the piston;
A chamber accommodating a gas supplied from the gas generator, and a guide path for transportably supporting an intermediate portion of the cable,
.

The pretensioner according to claim 1, wherein the noise preventing member is made of a plastic material.

The pretensioner according to claim 2, wherein the noise preventing member is fitted on or insert-injected onto the clamp.

The gas generator according to claim 1, wherein a part of the gas supplied from the gas generator is configured to pass through a gap between the piston and the cable,
And the clamp is fixed to the outer circumference of the cable by interference fit.

The pretensioner according to claim 4, wherein the noise preventing member is configured to form a gas hole communicating with the gap to leak gas generated from the gas generator to the clamp side.

The noise reduction device according to claim 1, wherein a protrusion is formed on a tip end portion of the noise prevention member,
And a seat groove is formed at a rear end portion of the piston to receive a tip end portion of the noise preventing member.