JPH08119059A - Air bag device - Google Patents

Abstract

PURPOSE: To reduce production man-hour and production cost by arranging and holding an air bag in a case with a strength maintained even if retainers, bolts, and nuts that were required before are not used, reducing the production man-hour and production cost of an air bag, and also reducing the number of component parts. CONSTITUTION: An air bag device is provided with a bag-shaped air bag 1, a cylinder type inflator 7, and a case 12 which surrounds the air bag 1 and the inflator 7 and holds both ends of the inflator 7. Also a rectangular opening part 2 to flow in gas from the inflator 7 is arranged at the lower part of the air bag 1, and tongue pieces 3 and 4 which extend downward and seamed to each other over the entire length of the lower end are formed on the peripheral edges of the opening part 2 alternately at opposed parts in lateral direction. The inflator 7 is inserted between the tongue pieces 3 and 4 of the air bag 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device arranged on an instrument panel or the like in front of a passenger seat of a vehicle.

[0002]

2. Description of the Related Art Conventionally, in this type of airbag device, as is known from Japanese Patent Laid-Open No. 5-286403,
It is composed of a folded bag-shaped airbag, a cylinder type inflator that supplies gas to the airbag, a case surrounding the airbag and the inflator, and a retainer that attaches the airbag to the case. It was

The retainer has a quadrangular annular shape to which a large number of downwardly projecting bolts are fixed. Each of these bolts is inserted into the periphery of the rectangular opening for allowing gas to flow into the airbag and the case, and A nut was screwed onto each bolt to attach the airbag to the case.

The case is composed of two upper and lower members so that a lower member holds both ends of the inflator so as to form a step portion in which a square annular retainer is arranged.

[0005]

Although the conventional airbag device has the above-described structure, it is necessary to form a large number of mounting holes into which the bolts are inserted at the peripheral edge of the opening of the airbag, and the peripheral edges of these mounting holes are formed. Since stress concentration is likely to occur when the airbag is inflated, it is necessary to sew for reinforcement such as disposing a reinforcing cloth and sewing the peripheral edge of the mounting hole.

Therefore, since the number of those mounting holes is large, the number of manufacturing steps and manufacturing cost of the air bag increases due to the formation of the mounting holes and the reinforcement of the peripheral edge of the mounting hole. It was a factor that increased the manufacturing cost.

Of course, since parts for bolts and nuts for attaching the airbag to the case are also required, these parts have also become a factor for increasing the manufacturing man-hours and manufacturing costs of the airbag device. .

The present invention is to solve the above-mentioned problems, and to secure the strength and retain the airbag in the case without using the retainer, bolt, nut, etc. which have been conventionally required. Accordingly, it is an object of the present invention to provide an airbag device capable of reducing the number of manufacturing steps and manufacturing cost of an airbag and reducing the number of constituent parts to reduce the number of manufacturing steps and manufacturing cost.

[0009]

An airbag device according to the present invention comprises a folded bag-shaped airbag, a cylinder type inflator for supplying gas to the airbag, and the periphery of the airbag and the inflator. And a case that holds both ends of the inflator, and a rectangular opening that allows gas from the inflator to flow into the lower portion of the airbag is provided. , Tongues extending downward and sewn together over the entire length of the lower end are formed at opposing portions in the lateral direction at the periphery of the opening, and the inflator is inserted between the tongues of the airbag. It is characterized by

2 in the inflator and its surroundings
A tubular protective tube having a gas flow hole may be disposed between the two tongue pieces.

The up-down direction in this specification is used to describe the relative positional relationship of each member, and does not refer to the up-down direction of the airbag device actually mounted on the vehicle. .

[0012]

In the airbag device according to the present invention, the inflator whose both ends are held by the case is inserted between the tongues of the airbag whose lower ends are sewn together. The two tongue pieces are wrapped around the outer peripheral surface of the inflator and held by the outer peripheral surface of the inflator. Since the tongue pieces are sewn together over the entire length of the lower end of the tongue pieces, stress concentration does not occur even when a large tensile load is applied when the airbag is inflated, and sufficient strength can be secured. it can.

Further, in such an air bag, since the conventional mounting holes are not required, it is not necessary to form a large number of mounting holes or to sew reinforcement around the periphery of the mounting holes, thereby reducing the number of manufacturing steps and manufacturing cost of the airbag. It can be reduced.

Even if the reinforcing cloth is sewn to reinforce the sewn portions between the tongues, the sewn for the reinforcement is the work of sewing the peripheral edges of a large number of attachment holes in a circular shape. Compared to the above, since the work is performed in a straight line, the work can be performed very easily, and it is possible to avoid a hindrance to the reduction of the manufacturing process and manufacturing cost of the airbag.

Furthermore, in the airbag device according to the present invention, the airbag is not directly held in the case by a retainer, bolts, nuts or the like, but is indirectly connected to the case via inflators whose both ends are held in the case. Since the retainer, bolts, nuts, etc., which have been conventionally required, are not required, the number of constituent parts can be reduced, and the number of assembling steps for them is also unnecessary.

Therefore, in the airbag device according to the present invention, the airbag can be disposed and held in the case while ensuring the strength without using the retainer, the bolt, the nut and the like which are conventionally required. It is possible to reduce the manufacturing man-hours and manufacturing costs of the airbag, and it is possible to reduce the manufacturing man-hours and manufacturing costs by reducing the number of constituent parts.

Further, if a tubular protective tube having a gas flow hole is arranged between the inflator and the two tongues around the inflator, the tongue of the airbag and the inflator come into direct contact with each other. Since this can be prevented, although the number of constituent parts is increased by 1, the airbag can be protected when the gas discharged from the inflator is at a high temperature. In addition, the flow of the gas discharged from the inflator can be adjusted by considering the arrangement position of the gas flow holes provided in the protection tube.

[0018]

An embodiment of the present invention will be described below with reference to the drawings.

The airbag device M of the embodiment shown in FIGS.
Reference numeral 1 denotes an airbag that is arranged on an instrument panel in front of a passenger seat of a vehicle, and is a folded bag-shaped airbag 1.
And an inflator 7 that supplies gas G to the airbag 1.
And a protective tube 24 arranged around the inflator 7.
And a case 12 that surrounds the periphery of the airbag 1 and the inflator 7 and holds both ends of the inflator 7, and a lid 22 that closes the opening 12a of the case 12.

The inflator 7 is of a cylinder type and has a cylindrical main body 8 in which a plurality of gas discharge ports 8a are arranged.
And a disk-shaped flange portion 9 formed at one end of the main body 8.
And a male screw portion 10 formed on the other end of the main body 8.

The case 12 has four side walls 13,14,1.
5 and 16 and the bottom wall 17 are arranged, and a rectangular opening 12a is arranged in the upper part, and it is formed of a sheet metal or the like into a substantially rectangular parallelepiped box shape.

An insertion hole 13a into which the main body 8 of the inflator 7 can be inserted and the flange portion 9 cannot be inserted into one side wall 13 of the case 12 which is opposed in the longitudinal direction.
The other side wall 14 is formed with an insertion hole 14a into which the male screw portion 10 of the inflator 7 can be inserted and the main body 8 cannot be inserted.

A square bracket 18 is fixed to the outer peripheral surface of the upper portion of the case 12, and four bolts 1 are attached to the bracket 18 at the positions where the side walls 15 and 16 are arranged.
9 is fixed. These bolts 19 are attached to the lid 22.
It is used when attaching.

The lid 22 is made of synthetic resin, and the case 1
Rectangular plate-shaped main body 22a that covers the second opening 12a
And a projecting piece 22b for attachment, which is provided to project downward from one end of the main body 22a, and a breakable projecting piece 22c, which is provided to project downward from the other end of the main body 22a. Mounting holes (not shown) into which the bolts 19 of the bracket 18 fixed to the case 12 are inserted are formed in each of the projecting pieces 22b and 22c, and the bolts 19 are inserted into the mounting holes (not shown) and the nuts 20 are screwed together. The lid 22 is attached to the case 12.

The airbag 1 is formed of a woven cloth such as nylon in the shape of a bag having a square tubular shape when inflated,
A rectangular opening 2 through which the gas G from the inflator 7 flows is arranged in the lower part.

Further, in the lower portion of the airbag 1, rectangular tongues 3 and 4 extending downward are formed at opposite sides in the lateral direction of the periphery of the opening 2, and these tongues are formed. The three and four parts are sewn together with a suture thread 5 made of nylon thread or the like over the entire length of the lower end.

The protective tube 24 is the main body 8 of the inflator 7.
As a cylindrical sheet metal with an inner diameter that can be inserted,
A plurality of gas circulation holes 24a penetrating the outer peripheral surface are provided, and a plurality of claw pieces 24b protruding inward are fixed to the inner peripheral surface. These claw pieces 24b come into contact with the outer peripheral surface of the inflator body 8 and serve to fix the protection tube 24 around the inflator body 8. Protective tube 2
4 is a space 6 between the tongue pieces 3 and 4 of the airbag 1
Size that can be inserted into the case 12 and its length
The distance between the side walls 13 and 14 is substantially equal.

The assembly of the airbag apparatus M1 of this embodiment will be described. First, the tongue piece 3 of the airbag 1
The protective tube 24 is inserted into the space 6 between the airbag 4 and the airbag 1
Fold.

After that, the airbag 1 is made so that the protective tube 24 is aligned with the insertion holes 13a and 14a of the side walls 13 and 14.
The tongue pieces 3 and 4 of the case 12 are inserted into the case 12, and then the male screw portion 10 side of the inflator 7 is inserted into the case 12 through the insertion hole 13a, and further, the protective tube 24 is inserted to insert the case 12 of the case 12 into the case 12. The flange portion 9 of the inflator 7 is brought into contact with the peripheral edge of the insertion hole 13a of the case 12 while protruding from the insertion hole 14a.

Then, the nut 11 is screwed into the male screw portion 10 to attach the inflator 7 to the case 12.

After that, a predetermined bolt 19 is inserted into a mounting hole (not shown) to attach each mounting projection 22b and the breaking projection 2.
When 2c and nut 20 are fastened and lid 22 is attached to case 12, the assembly of airbag device M1 is completed.

Air bag device M1 assembled in this way
When the gas G is discharged from the gas discharge port 8a of the inflator body 8 after being mounted on the instrument panel using a bracket (not shown) provided in the case 12, the gas G is the gas of the protective tube 24. While passing through the circulation hole 24a, the air flows into the airbag 1 from the opening 2 to inflate the airbag 1, and the airbag 1 breaks the breaking projections 22c and attaches the lid 22. The protrusion 22b is opened around the center of rotation, and the protrusion 12b is largely expanded from the opening 12a of the case 12.

When the airbag 1 is inflated, a large tensile load acts on the stitching portions of the tongues 3 and 4, but the tongues 3
Since the four stitches are sewn over the entire length of the lower ends of the tongue pieces 3 and 4, stress concentration does not occur and sufficient strength can be secured.

Therefore, in the airbag 1 of the embodiment,
Since a large number of mounting holes required for a conventional airbag are not required, it is not necessary to form a large number of mounting holes or to sew a peripheral portion of the mounting holes for reinforcement, thereby reducing the number of manufacturing steps and manufacturing cost of the airbag 1. It can be reduced.

Even if the reinforcing cloth 26 (see the chain double-dashed line in FIG. 3) is sewn to reinforce the sewn portions between the tongues 3 and 4, the sewn for the reinforcement is the conventional one. Compared with the work of sewing the peripheral edges of a large number of mounting holes in a circular shape, the work of linear sewing along the lower edges of the tongues 3 and 4 and both the left and right edges can be performed, so that it can be performed very easily, and the airbag 1
It is possible to avoid an obstacle to the reduction of manufacturing man-hours and manufacturing costs.

In the air bag device M1 of the embodiment, the air bag 1 is not directly held in the case by the retainer or a large number of bolts and nuts as in the conventional case.
Since both cases are indirectly held by the case 12 through the inflator 7 held by the case 12,
The required retainer, many bolts, nuts, etc. are no longer needed, and the number of parts of the protection tube 24 increases by one, but the number of constituent parts can be reduced and the assembly man-hours are also unnecessary. The cost can be reduced.

Further, like the airbag apparatus M1 of the embodiment, a tubular protection in which the gas flow hole 24a is arranged between the inflator body 8 and the two tongue pieces 3 and 4 around the inflator body 8. By disposing the tube 24, it is possible to prevent the tongues 3 and 4 of the airbag 1 and the inflator body 8 from directly contacting each other, so that the gas discharge port 8a of the inflator 7 is prevented.
When the gas G discharged from the air is hot, the airbag 1
It is possible to protect the tongue pieces 3 and 4 of. Also, the protection tube 2
Considering the arrangement position of the gas flow holes 24a arranged in No. 4, it becomes possible to adjust the flow of the gas G discharged from the inflator 7, and the inflation performance such as shortening of the inflation completion time in the airbag 1 is improved. Can be improved.

In this protection tube 24, the gas G discharged from the inflator 7 is not at a high temperature, and, for example, the inflator 7 mixes the combustion gas with the compressed gas G.
In the type in which the gas is discharged from the gas discharge port 8a, the gas G has a low temperature of 140 to 150 ° C., so that the protective tube 24 may not be used as shown in FIG. In addition, in such an airbag device M2, the number of manufacturing steps and the manufacturing cost of the airbag device M2 can be reduced as compared with the airbag device M1 because the number of parts of the protection tube 24 is smaller.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an airbag device showing an embodiment of the present invention.

2 is another vertical cross-sectional view of the same embodiment, taken along line II-II of FIG.
Corresponds to the part.

FIG. 3 is a perspective view of an airbag, a protective tube, an inflator, and a case of the same embodiment.

FIG. 4 is a longitudinal sectional view showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Airbag, 2 ... Opening part, 3.4 ... Tongue piece, 7 ... Inflator, 12 ... Case, 24 ... Protective tube, 24a ... Gas distribution hole, M1 * M2 ... Airbag apparatus.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazumi Ichimaru No. 1 Nagahata, Ochiai, Kasuga-cho, Nishikasugai-gun, Aichi Toyoda Gosei Co., Ltd. Toyoda Gosei Co., Ltd.

Claims (2)

[Claims] 1. A folded bag-shaped airbag, a cylinder type inflator that supplies gas to the airbag, and a case that surrounds the airbag and the inflator and holds both ends of the inflator. An airbag device configured to include a rectangular opening for allowing gas from the inflator to flow in at a lower portion of the airbag, and a portion in a lateral direction facing each other at a peripheral portion of the opening. To
An airbag device, wherein tongue pieces extending downward and sewn to each other along the entire length of a lower end thereof are formed, and the inflator is inserted between the tongue pieces of the airbag. 2. A cylindrical protection tube having a gas flow hole is disposed between the inflator and the two tongue pieces around the inflator. Airbag device.