JP2014144716A - Air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve weight saving and a cost reduction by eliminating a flange of an inflator.SOLUTION: An air bag device 1 comprises a bag-shaped folded air bag 2, an inflator 5 which is provided with a gas exhaust nozzle 7a supplying a gas for expansion to the air bag 2 and a retainer 4 for retaining the air bag 2 and the inflator 5. A female-screw-shaped part 6 is formed in the inner peripheral surface 4b of an insertion hole 4a of the retainer 4, and a male-screw-shaped part 9 is formed in the outer peripheral surface 5a of the inflator 5. A seal tape is wound around the male-screw-shaped part 9, and the female-screw-shaped part 6 and male-screw-shaped part 9 are screwed together to fix the inflator 5 to the retainer 4 in an air-tight manner.

Description

  The present invention relates to an airbag device that protects an occupant by inflating an airbag in the event of a vehicle collision.

Patent Documents 1 and 2 disclose an airbag device that protects an occupant by inflating an airbag into a vehicle with gas ejected from a gas ejection hole of an inflator when a vehicle collides.
For example, as shown in FIG. 5, a driver seat airbag device 50 disclosed in Patent Document 1 has a retainer 53 fixed to the inner peripheral surface of a cover 52 of a steering wheel 51 with a bolt or the like. 54 is supported.

The airbag module 54 includes an inflator 55 that generates high-pressure gas, an airbag 56 that is folded and inflated with high-pressure gas, and a ring plate 57 that fixes a base portion 56 a of the airbag 56 to the retainer 53. A flange 55 a provided on the outer periphery of the inflator 55 is fixed to the front surface of the retainer 53, and the base portion of the airbag 56 is sandwiched and fixed between the rear surface of the retainer 53 and the fixing ring 57.
Here, the airbag device 50 includes a connecting structure of a retainer 53 and an inflator 55 as shown in FIG. 6, for example. That is, the fastening bolt 58 attached to the ring plate 57 is fastened by screwing the nut 59 through the hole 53a formed in the retainer 53 and the hole 55b formed in the flange portion 55a of the inflator 55. Yes. Therefore, the inflator 55 has, for example, a substantially cylindrical outer peripheral surface, and gas ejection holes 60 are formed on the outer peripheral surface at predetermined intervals, and at the end of the outer peripheral surface opposite to the airbag 56. A flange 55a is formed to protrude.
The inflator 55 provided with such a flange 55a is also provided in the airbag device described in Patent Document 2.

Japanese Patent Laid-Open No. 2004-314738 JP 2000-52914 A

  However, since the inflator 55 in the airbag apparatus 50 described in Patent Document 1 and Patent Document 2 described above needs to be formed by protruding the flange 55a, the weight of the flange increases, and the manufacturing process of the airbag 56 is performed. However, there is a drawback that the processing cost rises because it takes man-hours. In addition, since the flange 55a of the inflator 55 is fastened to the bolt 58 with the four nuts 59, there is a disadvantage that the assembly cost increases. Further, since the flange 55a of the inflator 55 protrudes outward, the layout of the airbag device 50 is largely restricted depending on the height position of the inflator 55.

  In view of such problems, an object of the present invention is to provide an airbag device in which the flange of the inflator is eliminated and weight reduction and cost reduction can be achieved.

An airbag apparatus according to the present invention is an airbag apparatus including a folded bag-shaped airbag, an inflator that supplies inflation gas to the airbag, and a retainer that holds the airbag and the inflator. The retainer and the inflator are formed with an internal thread shape portion and the other with an external thread shape portion, and the internal thread shape portion and the external thread shape portion are screwed together so that the inflator is held by the retainer. .
According to the airbag device of the present invention, the retainer and the inflator can be connected by being screwed together with one female screw-shaped portion and the other male screw-shaped portion, and the inflator is not provided with a flange. The inflator can be miniaturized, manufacturing costs and assembly costs can be reduced, and restrictions on the layout of the airbag are reduced.

Moreover, it is preferable that a retainer has an insertion hole which can insert an inflator, and the internal thread shape part is formed in the internal peripheral surface of this insertion hole.
Moreover, it is preferable that the external thread shape part is formed in the outer peripheral surface of an inflator.
Since the internal thread shape portion is formed on the inner surface of the retainer insertion hole, the external thread shape portion formed on the outer peripheral surface of the inflator can be inserted and screwed in from the opposite side of the airbag or from the airbag side.

Moreover, it is preferable that the sealing member is provided between the external thread shape part and the internal thread shape part.
Since the male screw shape portion and the female screw shape portion are airtightly screwed through the seal member, it is possible to prevent the screw fastening portion from loosening and to prevent leakage of gas generated from the inflator.

Further, the female screw shape portion and the male screw shape portion may be formed on a tapered surface whose diameter increases in a direction away from the airbag.
Even if the thread of the male thread shape part or female thread shape part is crushed due to the impact when the airbag is deployed during gas ejection, the insertion holes of the inflator and the retainer contact the tapered surfaces of the male thread shape part and the female thread shape part. Since it is in contact, the inflator can be prevented from coming off to the airbag side.

  According to the airbag device of the present invention, the inflator can be directly fixed to the retainer with the male screw forming portion and the female screw forming portion without providing a flange. Assembling costs can be reduced.

It is a principal part disassembled perspective view of the airbag apparatus by embodiment of this invention. In the airbag apparatus by embodiment, it is a principal part perspective view of the state which connected the retainer and the inflator. It is a center longitudinal cross-sectional view of the retainer and inflator shown in FIG. It is the A section enlarged view shown in FIG. It is principal part sectional drawing of the conventional airbag apparatus. It is a disassembled perspective view of the airbag in a conventional airbag apparatus, a retainer, and an inflator.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, unless otherwise specified, up and down means up and down with respect to the vehicle.
1 to 4 show an airbag apparatus 1 according to an embodiment of the present invention. 1 and 2, the base 2a of the folded bag-like airbag 2 is sandwiched between the fixing ring 3 and the retainer 4, and includes bolts and nuts (not shown). It is fixed by various fastening means.

The retainer 4 is formed with an insertion hole 4a for fixing the inflator 5 at a substantially center of the plate shape, and an inner peripheral surface 4b of the insertion hole 4a is formed in a substantially truncated cone shape having a tapered surface with a small inclination, for example. An internal thread shape portion 6 made of an internal thread is formed on the surface 4b.
The inflator 5 has an outer circumferential surface 5a formed in a substantially cylindrical shape, and gas ejection holes 7a for ejecting gas are formed in the circumferential direction at predetermined intervals in the upper region 7 of the outer circumferential surface 5a. In addition, the lower region 8 of the outer peripheral surface 5a of the inflator 5 is formed in a substantially truncated cone shape made of, for example, a tapered surface with a small inclination, and a male screw shape portion 9 that is screwed into the female screw shape portion 6 of the retainer 4 is formed. . In the present embodiment, the upper part is the airbag 2 side, and the lower part is the opposite side (squib side) of the airbag 2.

Here, the retainer 4 is made of, for example, metal or synthetic resin, and when the retainer 4 is made of metal, at least the thickness of the insertion hole 4a is equal so that stress concentration due to load or pressure does not occur. It is preferable that there is no portion where the wall thickness decreases. Moreover, as shown in FIGS. 3 and 4, the female screw-shaped portion 6 formed on the inner peripheral surface 4 b of the insertion hole 4 a is formed by a ridge portion and a valley portion where the screw portion is gentle, and has a margin of at least two ridges or more. Is formed.
In addition, when the retainer 4 is made of a synthetic resin, the retainer 4 is formed to have a thickness sufficient to ensure sufficient strength, and has the same configuration as that of a metal.

  The inflator 5 is also made of a metal or a synthetic resin, like the retainer 4. The male thread shape portion 9 formed in the lower region 8 of the outer peripheral surface 5a is also formed with a ridge portion and a valley portion where the screw portion is gentle, and a margin of at least two ridges is formed.

As shown in FIGS. 3 and 4, the inner peripheral surface 4 b of the insertion hole 4 a of the retainer 4 is formed as a tapered surface with a small inclination so that the inner diameter increases in the direction away from the airbag 2. Similarly, the lower region 8 on the outer peripheral surface 5a of the inflator 5 is also formed with a tapered surface with a small inclination so that the inner diameter increases in the direction away from the airbag 2.
Therefore, when the male screw shape portion 9 of the inflator 5 is screwed into the female screw shape portion 6 of the insertion hole 4a of the retainer 4, the taper inclination is small, so that the screwing of the female screw shape portion 6 and the male screw shape portion 9 is not hindered. . Even if any one of the screw threads is crushed, the internal thread shape portion 6 and the external thread shape portion 9 are formed in a tapered shape, so that the inflator 5 comes out above the insertion hole 4a (the airbag 2 side portion). Can be prevented.

In addition, the seal tape 12 is wound around the entire circumference of the male thread-shaped portion 9 of the inflator 5 so as to be wound around one layer or a plurality of layers in advance. Therefore, in a state where the male thread forming portion 9 of the inflator 5 is screwed into the female thread forming portion 6 of the retainer 4, the seal tape 12 exhibits a packing function, and the gas ejected from the gas ejection hole 7 a of the inflator 5 is exposed to the outside. It can prevent leakage.
The other configuration of the airbag device 1 is the same as that of the conventional airbag device 50.

Since the airbag apparatus 1 according to the present embodiment has the above-described configuration, the upper region 7 protrudes from the insertion hole 4a by screwing the male screw shape portion 9 of the inflator 5 with the female screw shape portion 6 of the insertion hole 4a of the retainer 4. The inflator 5 that can be fixed to each other at the positions where the flanges are not provided can be reduced in weight and the manufacturing cost can be reduced.
In addition, since the sealing tape 12 is wound around the male screw-shaped portion 9 in advance and airtightly engaged with the female screw-shaped portion 6, gas leakage can be prevented.
Further, since the female thread-shaped portion 6 of the insertion hole 4a of the retainer 4 and the male thread-shaped portion 9 of the inflator 5 are formed in a tapered surface shape, even when the gas is ejected, even if the thread is crushed by the impact during the airbag deployment. The inflator 5 can be prevented from coming off to the facing side, that is, the airbag 2 side, and can be securely fixed and held without a flange.

In addition, the airbag apparatus by this invention is not limited to the above-mentioned embodiment, A various change, substitution, etc. are possible in the range which does not deviate from the summary.
For example, the taper surfaces formed on the inner peripheral surface 4b of the insertion hole 4a of the retainer 4 and the outer peripheral surface 5a of the inflator 5 are provided on the entire length of the female screw-shaped portion 6 and the male screw-shaped portion 9 in the embodiment, but are formed at least partially. It is sufficient to prevent the inflator 5 from coming off.

In addition, the sealing tape 11 is wound and attached to the male thread-shaped portion 9, but is not limited to the seal tape, and may be, for example, a film-like rubber, an adhesive, or the like. The female thread-shaped portion 6 and the male thread-shaped portion 9 Any sealing member may be used as long as it can be hermetically sealed. Further, it is not necessary to provide a sealing member such as a sealing tape.
Moreover, although the external thread shape part 9 was formed in the outer peripheral surface 5a of the inflator 5, and the internal thread shape part 6 was formed in the insertion hole 4a of the retainer 4, arrangement | positioning of the external thread shape part 9 and the internal thread shape part 6 may be reversed. .
Further, a male thread shape portion 9 is formed on the outer peripheral surface 5 a of the inflator 5, a female thread shape portion 6 is formed in the insertion hole 4 a of the retainer 4, and the tapered surface has a small inclination so that the inner diameter increases in the direction away from the airbag 2. However, it may be formed on a cylindrical surface without forming a tapered surface. In this case, the screwability of the male screw shape portion 9 and the female screw shape portion 6 is improved.

DESCRIPTION OF SYMBOLS 1 Airbag apparatus 2 Airbag 4 Retainer 4a Insertion hole 5 Inflator 5a Outer peripheral surface 6 Female thread shape part 9 Male thread shape part 12 Seal tape

Claims (5)

An airbag device comprising a folded bag-like airbag, an inflator that supplies inflation gas to the airbag, and a retainer that holds the airbag and the inflator,
Forming a female thread shape part on one of the retainer and the inflator, forming a male thread shape part on the other,
The airbag device is characterized in that the inflator is held by a retainer by screwing the female screw shape portion and the male screw shape portion.   The airbag device according to claim 1, wherein the retainer has an insertion hole into which an inflator can be inserted, and the female thread-shaped portion is formed on an inner peripheral surface of the insertion hole.   The airbag apparatus described in Claim 1 or 2 with which the said external thread shape part is formed in the outer peripheral surface of the said inflator.   The airbag apparatus described in any one of Claims 1 thru | or 3 with which the sealing member is provided between the said external thread shape part and an internal thread shape part.   5. The airbag device according to claim 1, wherein the female screw-shaped portion and the male screw-shaped portion are formed on a tapered surface whose outer diameter increases in a direction away from the airbag.

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