JP2002255006A - Inflator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inflator with increased reliability. SOLUTION: An ignitor 26 comprises a charge holder 37 for providing a detonation wave generated by the combustion of ignition charge 36 with directivity. Thus, a rupture plate 19 can be easily ruptured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inflator which is mounted on various vehicles and the like and mainly protects an occupant when the vehicle receives an impact from a lateral direction, and an airbag device using the same.

[0002]

2. Description of the Related Art An inflator for an inflatable safety system of a motor vehicle is provided with an inflator for protecting an occupant optimally according to a seat position in a vehicle such as a driver's seat and a passenger seat. Driver airbag inflator, passenger airbag inflator, side airbag inflator, curtain inflator, knee bolster inflator, inflatable seat belt inflator, tubular system inflator, pretensioner inflator, etc. Inflators are known. Among these inflators, a curtain inflator is for inflating and deploying a curtain-shaped airbag having a thickness of about several cm on a window side of a vehicle when the vehicle receives an impact from a lateral direction.

[0003] In such a curtain inflator, when the rupturable plate is broken, the pressurized medium starts to flow out, and the curtain-shaped airbag is finally inflated and deployed. Do not use gunpowder)
It is important to enhance the destructibility of the rupturable plate in order to enhance the operation reliability of the inflator.

[0004] As a related prior art, USP
Japanese Patent No. 5,527,066 discloses an apparatus for expanding a flexible container by using helium and hydrogen in combination, and US Pat. No. 5,782,486 discloses that a pressurized inert gas is supplied. A gas flow device for an airbag used is disclosed, and Japanese Patent No. 3,680,886 discloses an airbag device for inflating an airbag with nitrogen or helium. No. 493 describes:
A side inflator housing for an air bag using both a pressurized gas and a gas generating agent is disclosed, and Japanese Utility Model Publication No. 3031246 discloses a pressurized gas inflator using argon or nitrogen as a pressurized gas. I have.

[0005] It is an object of the present invention to provide an inflator capable of achieving a reduction in size and weight and having improved operation reliability, and an airbag device using the inflator.

[0006]

The inflator according to the present invention can be applied as both a curtain inflator and a side inflator for side impact, but the following description is based on the case where the invention is applied as a curtain inflator. I do.

According to the present invention, there is provided an inflator housing which is filled with a pressurized medium and has an opening at one end side, and a pump which is connected to the opening side of the inflator housing and which flows out of the opening during operation. A diffuser portion having a gas outlet for discharging the pressurized medium to the outside, and an outflow path of the pressurized medium between the opening of the inflator housing and the diffuser portion is closed by a rupturable plate; An inflator provided with an igniter provided with an igniter for destroying a rupturable plate by a detonation wave, and further provided with an igniter selected from the following (a) to (d):
Or an inflator having a combination of two or more requirements.

(A) The igniter has a charge holder for giving a directivity to a detonation wave generated by combustion of the ignition charge.

(B) The igniter has a cup arranged so as to contain at least the igniting charge, and has a weak portion in a portion of the cup facing the rupturable plate.

(C) The explosive is attached to the surface of the rupturable plate.

(D) The rupturable plate has a fragile portion.

[0012] In the requirement (a), the charge holder may be arranged so as to surround at least the igniter portion of the igniter from the surroundings, and the side facing the rupturable plate may be opened.

By providing the charge holder and directing the detonation wave (flame) generated by the combustion of the igniter, that is, the detonation wave is directed toward the rupture plate, the rupture plate is more reliably destroyed. Operation reliability is enhanced.

In requirement (b), the fragile portion may be such that the portion of the cup facing the rupturable plate is damaged or thinner than other portions. This fragile portion may be provided on either the outer surface or the inner surface of the portion of the cup facing the rupturable plate.

Further, in the requirement (b), the fragile portion may have a single scratch on the portion of the cup facing the rupturable plate, or may have two or more orthogonal or oblique scratches. It can be thin in a circular or similar shape. Here, two orthogonal scratches are cross-shaped scratches, and two or more oblique scratches are X
It is a flaw such as a letter or a letter Y.

Since the portion of the igniter cup facing the rupturable plate has a fragile portion as described above, the cup ruptures at the fragile portion when the igniter operates and the igniter ignites and burns. The detonation wave (flame) passing through the rupture portion travels straight toward the rupture disk with a narrow width, so that the rupture disk can be more reliably destroyed and the operation reliability is enhanced.

In the requirement (c), the rupturable plate may have a structure in which explosive is attached to a side facing the igniter.

When the explosive is attached to the rupturable plate in this way, when the detonation wave arrives and the rupturable plate is heated, the explosive ignited and burned by the heat destroys the rupturable plate more reliably. Operating reliability is increased.

In the requirement (d), the weak portion may be partially damaged or thinner than other portions. This fragile portion may be provided on any surface of the rupturable plate.

Further, in the requirement (d), the fragile portion may have a structure in which two or more partially orthogonal or oblique scratches are formed or the weak portion is thinned into a circular shape or a similar shape. . Here, two orthogonal scratches are cross-shaped scratches, and two or more oblique scratches are X-shaped or Y-shaped scratches.

Since the rupturable plate has the fragile portion as described above, when the igniter operates and the igniter ignites and burns, the rupturable plate ruptures at the fragile portion, so that the rupturable plate is more reliably destroyed. Operation reliability is enhanced.

The inflator of the present invention has one of the above requirements (a) to (d), a combination of two requirements, a combination of three requirements, or a combination of four requirements. However, it is preferable that the requirement (a) and the requirement (b) are satisfied.

In the inflator according to the present invention, the igniter and the rupturable plate may have a structure in which the igniter and the rupturable plate are arranged facing each other at a required interval, for example, an interval of about 5 mm or less. Here, the required interval is an interval that does not impair the outflow of the pressurized medium because the outflow of the pressurized medium may be impaired if the rupturable plate and the igniter are too close to each other. .

In the inflator according to the present invention, the rupturable plate may have a bowl shape protruding toward the igniter.

In each of the above inventions, the rupturable plate can be attached to the opening side or the diffuser side of the inflator housing.

Further, the present invention provides an airbag device provided with an operation signal output means including an impact sensor and a control unit, and a module case in which the inflator and the airbag are housed in a case.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an inflator 1 according to the present invention.
FIG. 4 is a cross-sectional view in the length direction of the inflator 10 according to another embodiment.

The inflator housing 12 has an opening 14 at one end and is closed at the other end, and a pressurized medium made of an inert gas such as argon or helium or a nitrogen gas is contained in the internal space 16. It is filled at a maximum pressure of about 70,000 kPa. The cross section of the inflator housing 12 in the width direction is circular, and the opening 14 is also circular.

The inflator housing 12 can use an existing gas cylinder, and can be manufactured by swaging a pipe. Inflator 10 of FIG.
Fills the pressurized medium from the opening 14 of the inflator housing 12. In the inflator 10 of FIG. 4, after the diffuser portion 20 is connected to the inflator housing 12, the inflator 10 is filled through a gap between the seal pins 13 fitted into the fine holes.
Thereafter, the inflator housing 12 is welded to the seal pin 13 and completely closed.

Opening 14 of inflator housing 12
The diffuser unit 20 is connected to the side. The diffuser section 20 has an outer shell formed by a diffuser housing 23, and has a gas discharge port 22 on its peripheral surface for allowing the pressurized medium to flow out.

The inflator housing 12 and the diffuser portion 20 may be connected by welding, or a male screw portion may be provided on an outer peripheral surface of an end portion of the inflator housing 12 and a female screw portion may be provided on an inner peripheral surface of an end portion of the diffuser portion 20. Alternatively, the male screw portion and the female screw portion may be screwed and connected.

Opening 14 of inflator housing 12
Is closed by a bowl-shaped rupturable plate 19, and before operation, the internal space 16 of the inflator housing 12 is maintained in a high-pressure airtight state. On the other hand, the gas outlet 22 of the diffuser section 20 is not closed.

The diffuser section 20 is provided with an igniter 26 provided with an igniter as a means for breaking the rupturable plate 19. The igniter 26 is connected to the diffuser housing 23
And is attached to the diffuser portion 20. 30 is a connector, and 32 is a lead wire for connecting to a power supply.

The diffuser section 20 has a gas exhaust port 4
These are connected by connecting the gas discharge port 22 of the diffuser section 20 and the communication hole 42 of the gas discharge port 40 and then welding them at a welding section 44.

The gas discharge port 40 is mounted so that the central axis of the inflator housing 12 (dashed line in FIG. 1) and the central axis of the gas discharge port 40 (dashed line in FIG. 1) are parallel to each other. .

The gas discharge port 40 is formed of a tubular member having one end closed and an opening 46 formed at the other end, and a filter 48 for removing foreign matter near the opening 46. Is provided. This filter 48
For example, a wire mesh or a laminate of wire mesh can be used. The installation place of the filter 48 is not particularly limited as long as foreign matter in the pressurized medium flowing out can be removed.
For example, it may be provided so as to cover the communication hole 42 from the passageway 49 side of the pressurized medium.

In the inflator 10 of the present embodiment, the means shown by requirements (a) to (d) are provided as means for further improving the destructiveness of the rupturable plate 19. (1) Means indicated by requirement (a) As shown in FIG.
A cylindrical charge holder 37 is provided so as to wrap around the disk-shaped ignition charge 36 from the surroundings, and the side of the charge holder 37 facing the rupturable plate 19 is opened. The charge holder 37 imparts directivity to the detonation waves generated by the combustion of the ignition charge. In addition, 3
Reference numeral 8 denotes a cup indicated by the requirement (b). (2) Means indicated by requirement (b) A cup 38 is arranged so as to include the ignition portion 35 and the ignition charge 36 of the igniter 26, and the outer surface of the portion of the cup 38 facing the rupturable plate 19 has A cruciform wound as shown in FIG. 3 is provided, and the cup 38 ruptures at the cruciform wound, giving the detonation wave directivity. (3) Means indicated by requirement (c) A small amount of explosive 39 is attached to the convex side of the bowl-shaped rupturable plate 19, and when that portion is heated, the explosive ignites and burns due to the heat. This facilitates the rupture of the rupturable plate 19. (4) Means shown by requirement (d) A cruciform wound which becomes a fragile portion as shown in FIG. 3 is formed on the convex side or the concave side of the bowl-shaped rupturable plate 19. The bursting of the rupturable plate 19 is facilitated.

Next, another embodiment shown in FIG. 4 will be described. The inflator 10 shown in FIG.
9 has the same structure as that of the inflator 10 shown in FIG. 1 except that the attachment site is different and the method of filling the pressurized medium is different (there is a seal pin 13).

In the inflator 10 shown in FIG.
The rupturable plate 19 is connected to the opening 14 of the inflator housing 12.
The inflator 1 shown in FIG.
At 0, the rupturable plate 19 is attached to the periphery of the opening 21 of the diffuser portion 20. The opening 14 of the inflator housing 12 and the opening 21 of the diffuser section 20 can be arranged so as to be in contact with each other, but as shown in FIG.
It is desirable to arrange them so that a gap is formed between them. The size of the gap can be adjusted by appropriately setting the length from the opening 21 of the diffuser section 20 to the tip 23a of the diffuser housing 23. At this time, the tip portion 23a is connected to the inflated portion 1 of the inflator housing 12.
5 makes it easy to join by welding.

Next, the operation of the inflator 10 of the present invention will be described. When mounted on a vehicle, the inflator 10 is installed as a system combining an operation signal output unit including an impact sensor and a control unit, a module case in which the inflator 10 and a curtain-shaped airbag are housed in a case, and the like. The curtain-shaped airbag is connected at an opening 46 of the gas discharge port 40.

First, when a vehicle receives an impact, the signal from the impact sensor of the system is received, the igniter 26 is activated, and the igniter ignites and burns, so that the rupturable plate 19 is broken. When the rupturable plate 19 is destroyed, the above requirement (a)
(D), the rupturable plate 1
9 is made easier.

Since the opening 14 is opened by the destruction of the rupturable plate 19, the pressurized medium in the internal space 16 flows out of the gas discharge port 22, passes through the communication hole 42, and passes through the gas discharge port 4.
0, flows out of the opening 46 through the filter 48, and inflates the curtain-shaped airbag. In addition, if fragments are generated when the rupturable plate 19 ruptures, the fragments are removed by the filter 48 to prevent the outflow into the curtain-shaped airbag.

[0043]

According to the inflator of the present invention, the requirements (a) to
By having the means selected from (d), the destructibility of the rupturable plate is enhanced, and the operation reliability for the inflator is also high.

When the inflator of the present invention is applied as a side inflator, the gas discharge port 40 becomes unnecessary, and an air bag is connected to the gas discharge port 22 directly or via an appropriate adapter.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the inflator of the present invention in the length direction.

FIG. 2 is a partially enlarged view of the inflator of FIG.

FIG. 3 is an explanatory view of the state of the surface of the cup or the rupturable plate of FIG. 1;

FIG. 4 is a longitudinal sectional view of another embodiment of the inflator of the present invention.

[Explanation of symbols]

 Reference Signs List 10 inflator 12 inflator housing 14 opening 19 rupture plate 20 diffuser part 22 gas outlet 26 igniter 40 gas discharge port 42 communication hole 48 filter

Claims (12)

[Claims] 1. An inflator housing filled with a pressurized medium and having an opening at one end side, and connected to the opening side of the inflator housing to discharge the pressurized medium flowing out of the opening during operation to the outside. It has a diffuser part with a gas outlet, and the outflow path of the pressurized medium between the opening part of the inflator housing and the diffuser part is closed by a rupture plate, and the rupture plate is destroyed by a detonation wave in the diffuser part. An inflator provided with an igniter provided with an igniting charge for performing
An inflator having one requirement selected from (d) or a combination of two or more requirements. (A) The igniter has a charge holder for giving directionality to a detonation wave generated by combustion of the ignition charge. (B) The igniter has a cup arranged so as to contain at least the igniting charge, and has a fragile portion in a portion of the cup facing the rupturable plate. (C) explosives are adhered to the surface of the rupturable plate. (D) The rupturable plate has a fragile portion. 2. The charge holder according to requirement (a), wherein the charge holder is arranged so as to surround at least the igniter portion of the igniter from the surroundings, and has an opening on the side facing the rupturable plate.
Inflator as described. 3. The inflator according to claim 1, wherein the fragile portion of the requirement (b) is such that a portion of the cup facing the rupturable plate is damaged or thinner than other portions. 4. The fragile portion of the requirement (b) has a single wound, two or more orthogonal or oblique scratches on a portion of the cup facing the rupturable plate, or a circular or similar shape. The inflator according to claim 1 or 3, wherein the inflator is thin. 5. The inflator according to claim 1, wherein the rupturable plate of the requirement (c) has an explosive attached to a side facing the igniter. 6. The inflator according to claim 1, wherein the weak part of the requirement (d) is partially damaged or thinner than other parts. 7. The fragile portion of the requirement (d) has one flaw, two or more perpendicular or oblique flaws, or is thinned to have a circular or similar shape. The inflator according to claim 1 or 6, wherein 8. The inflator according to claim 1, comprising requirement (a) and requirement (b). 9. The inflator according to claim 1, wherein the igniter and the rupturable plate are arranged to face each other at a predetermined interval. 10. The inflator according to claim 1, wherein the rupturable plate has a bowl shape protruding toward the igniter. 11. The inflator according to claim 1, wherein the rupturable plate is attached to an opening side or a diffuser side of the inflator housing. 12. An operation signal output means comprising an impact sensor and a control unit, and a case is provided in the case.
An airbag device, comprising: the inflator according to any one of Claims 1 and a module case in which the airbag is housed.