JPH0558242A - Air bag device - Google Patents

Abstract

PURPOSE:To reduce manhour by molding an annular reinforcing member from thermoplastic synthetic resin and forming an integral body through thermal fusion when the annular reinforcing member formed on the peripheral edge part of the opened port of an air bag is fixed, for an inflator installation member so as to surround a high pressure gas injection hole of the inflator. CONSTITUTION:An air bag device 1 is fixed by screws 6 through the insertion of an inflator 5, into an installation hole 4 formed on the bottom wall 3 of an inflator case 2. Further, a high pressure gas injection hole 7 is formed at the part projecting over the inflator 5. Further, on the outer periphery of a cylindrical part 9 of the inflator case 2, an air bag accommodation cover 8 is fixed, and an air bag 10 in folded state is accommodated inside. As for the air bag 10, an annular reinforcing part 11 formed on the periphery of the opened port part is fixed on the cylindrical part 9 by screws 12. In this case, the annular reinforcing part 11 is made of thermoplastic synthetic resin, and thermally fused integrally with the peripheral edge of the opened port part simultaneously with injection molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air bag device used in an automobile. More specifically, the present invention relates to an airbag device for protecting an occupant from a collision when an air bag (airbag) provided in front of a seat of a vehicle is inflated with high-pressure gas momentarily.

[0002]

2. Description of the Related Art In recent years, equipment for airbags has been legalized in Japan in order to reduce the mortality rate of traffic accidents. The airbag device has a folded airbag housed in an airbag cover. When the airbag is inflated, the airbag cover is torn along a slit formed therein to open, and the airbag projects from the opening to protect an occupant.

An example of a conventional air bag device is shown in FIG. The airbag device has a tubular inflator case 52 having an open upper end. Inflator 5
5 is attached to the hole 54 formed in the bottom wall 53 of the case 52, and the portion where the high pressure gas injection hole 56 is provided is the case 52.
Protruding above.

An air bag storage cover 57 is fixed to the outer periphery of the tubular portion 58 of the inflator case 52, and the air bag 51 is stored in the storage cover 57 in a folded state. The airbag 51 is fixed to the tubular portion 58 of the inflator case 52 at the peripheral edge of the opening. That is, the airbag 51 is fixed to the inflator case 52 by applying the reinforcing ring 59 to the periphery of the opening of the airbag 51 and screwing the reinforcing ring 59 to the tubular portion 58.

[0005]

In the conventional air bag device described above, the reinforcing ring 59 and the air bag 1 are separately molded and integrated by screws. Therefore, there is a problem that the number of steps for assembling the airbag device is large and the mounting work is troublesome.

The present invention has been made based on the above technical background, and achieves the following objects.

It is an object of the present invention to provide an air bag device which requires less man-hours for assembly and is easy to manufacture.

[0008]

In order to achieve the above object, the following means are adopted.

That is, according to the present invention, an inflator mounting member to which an inflator is mounted, and an annular reinforcing portion is formed at the peripheral edge of the opening. An airbag device having an airbag to be fixed, wherein the annular reinforcing portion is integrally heat-sealed to the peripheral edge of the opening by a molding method of thermoplastic synthetic resin. ..

A plurality of punched holes are formed around the opening of the airbag, and the punched holes are filled with the thermoplastic resin forming the annular reinforcing portion.

Further, the present invention is an airbag apparatus having an inflator mounting member to which an inflator is mounted, and an airbag fixed to the inflator mounting member so as to surround a high pressure gas injection hole of the inflator at a peripheral edge of the opening. , A plurality of punched holes are formed around the opening of the airbag, and the airbag is
It is fixed to the inflator mounting member through an annular fixing portion integrally heat-sealed to the surface of the airbag, the punched hole and the surface of the insulator mounting member by a molding method of thermoplastic synthetic resin. It is a characteristic airbag device.

A recess is formed on the surface of the inflator mounting member, and the thermoplastic synthetic resin forming the annular fixing portion is integrally heat-sealed to the recess.

[0013]

[Operation] Since the annular reinforcing portion is formed by integrally heat-sealing the thermoplastic synthetic resin to the airbag, the number of parts at the time of assembly is reduced, and the assembly of the airbag device is facilitated.

Further, by fixing the airbag itself to the inflator mounting member at the same time as molding the same through the annular fixing portion of thermoplastic synthetic resin, the number of processing steps is reduced and the assembling is further facilitated.

[0015]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an airbag device according to the present invention. The airbag device 1 has a tubular inflator case 2 having an open upper end. The inflator case 2 is made of an injection-molded thermoplastic engineering plastic or a metal plate.

A mounting hole 4 is formed in the bottom wall 3 of the inflator case 2.
Is provided, and the inflator 5 is fixed to the bottom wall 3 by the screw 6 while being inserted into the mounting hole 4.

The inflator 5 is a gas generator for generating high-pressure gas, and a high-pressure gas ejection hole 7 is provided in a portion protruding above the inflator case 2. The airbag storage cover 8 is fixed to the outer periphery of the tubular portion 9 of the inflator case 2, and the airbag 10 is stored in the storage cover 8 in a folded state.

An annular reinforcing portion 11 is formed on the periphery of the opening of the airbag 10, and the airbag 10 is fixed to the tubular portion 9 by screws 12 at the annular reinforcing portion 11. The airbag device 1 as described above is attached to the steering wheel in the inflator case 3 via a bracket (not shown). When a sensor (not shown) detects the collision of the vehicle, the inflator 5 generates high pressure gas. The high-pressure gas is injected from the injection hole 7, whereby the airbag 10 is inflated, the storage cover 8 is broken at the break portion 14 in the center thereof, and the expanded airbag 10 is inflated.
Is released into the vehicle interior.

The airbag 10 is a thread material made of synthetic resin,
It is preferably formed by weaving fine denier of nylon 66. The annular reinforcing portion 11 is made of synthetic resin, and is integrally heat-sealed to the peripheral edge of the opening portion of the airbag 10 simultaneously with the molding by injection molding.

Molding Method FIG. 2 shows a molding method of the annular reinforcing portion 11. The airbag 10 is preliminarily formed with a plurality of punched holes 13 at circumferential intervals in the periphery of the opening (FIG. 3).
reference).

The first die 21 and the second die 22 during molding
The peripheral edge of the opening of the airbag 10 is sandwiched between and the other part of the airbag 10 has a hole 23 formed in the first mold 21.
Housed inside. The cavity 2 formed on both sides of the punched hole 13 by the first mold 21 and the second mold 22.
Into 4, a thermoplastic elastic body heated and melted is introduced from a sprue (not shown).

The thermoplastic elastic body is selected from, for example, nylon elastomer, polyurethane elastomer, olefin elastomer, polyester elastomer and the like. The injected resin passes through the sprue and runner, passes through the gate, and fills the cavity 24. The thermoplastic elastic body flowing into the cavity 24 partially melts the surface portions of the airbag 10 and the punched holes 13 by its own heat of fusion, and both are mixed or adhered to each other to form a heat-bonded surface. In this way, as shown in FIGS. 4 and 5, the annular reinforcing portion 11 is formed, and the airbag 10 is taken out from the molds 21 and 22 to perform other processing.

In the example shown in FIG. 5, the annular reinforcing portions 11 are formed on both sides of the punched hole 13, but the annular reinforcing portions may be formed on only one side of the punched hole 13, as shown in FIG. .. Further, the annular reinforcing portion does not necessarily have to be continuous, and a plurality of reinforcing portions may be provided at intervals in the circumferential direction so that these reinforcing portions are annular as a whole.

The punched hole 13 is not always necessary.
An annular reinforcing portion may be formed around the opening of the airbag without providing this. In this case, when the primer is applied to the periphery of the opening in advance and the annular reinforcing portion is injection-molded, the annular reinforcing portion is more firmly fixed to the airbag. Silicon or the like can be appropriately selected as the primer.

[Other Thermoplastic Elastic Body of Annular Reinforcement]
In addition to the above-mentioned nylon, a thread material of engineering plastic such as polycarbonate is used for the airbag 10. However, in order to join the thermoplastic elastomer conventionally used as the annular reinforcing portion to these engineering plastics, it is limited to a relatively hard thermoplastic elastic body (elastomer). In this case, the applicant of the present invention discloses Japanese Patent Application Laid-Open Nos. 1-139240 and 1-139224.
No. 1 and Japanese Patent Application No. 1-235620 (Japanese Patent Application Laid-Open No. 3-10
The thermoplastic elastic body composition may be selected according to the method proposed in Japanese Patent Laid-Open No. 0045).

Further, the annular reinforcing portion is not limited to the thermoplastic elastic material, but may be ABS, polycarbonate (PC), polypropylene (PP), PBT, nylon 6, nylon 11,
Engineering plastic having good mechanical strength and moldability such as nylon 12 may be used.

[Second Embodiment] FIGS. 7, 8 and 9 are sectional views showing a second embodiment of the present invention. In this embodiment, the airbag 10 is fixed to the inflator case 2 via a fixing member 27.

The material of the inflator case 2 is preferably the above-listed engineering plastics, but may be a metal if it is primed.

The annular groove 2 is formed on the end surface of the tubular portion 9 of the inflator case 2 of the molding method.
5 is formed. Further, a punching hole 13 is formed in the periphery of the opening of the airbag 10 as in the first embodiment.

The inflator case 2 is housed in the hole 30 formed in the first mold 21.
The peripheral edge of the opening of the airbag 10 is arranged on the end surface of the airbag 10.

Cavity 26 formed in the second mold 22
Then, a thermoplastic elastic body heated and melted is introduced from a sprue (not shown).

This thermoplastic elastic body is similar to the above-mentioned annular reinforcing portion. The inflowing resin is sprue,
Cavity 26 and hole 2 through the runner and through the gate
5 is satisfied. The thermoplastic elastic body that has flowed into the cavity 26 partially melts the surface portions of the airbag 10, the punched holes 13 and the holes 25, and the two are mixed or adhered to form a heat-sealed surface.

In this way, the annular fixing portion 27 is formed (see FIG. 9), and the airbag 10 is fixed to the inflator case 2 by the annular fixing portion 27.

[0034]

As described in detail above, according to the present invention, since the annular reinforcing portion made of the thermoplastic synthetic resin is integrally heat-bonded to the airbag, the number of parts at the time of assembly is reduced. As a result, the assembly of the airbag device becomes easy.

Further, by fixing the airbag itself to the inflator attaching member at the same time as forming the same through the annular fixing portion of the thermoplastic synthetic resin, the number of processing steps is reduced and the assembling is further facilitated.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an airbag device according to the present invention.

FIG. 2 is a cross-sectional view showing a method for forming an annular reinforcing portion.

FIG. 3 is an oblique-axis projection view showing the entire airbag before forming the annular reinforcing portion.

FIG. 4 is an oblique-axis projection view showing the entire airbag in which an annular reinforcing portion is formed.

FIG. 5 is a cross-sectional view showing an annular reinforcing portion.

FIG. 6 is a cross-sectional view showing another example of the annular reinforcing portion.

FIG. 7 is a cross-sectional view showing a method for molding an annular fixing portion according to the second embodiment of the present invention.

FIG. 8 is an oblique-axis projection view showing the inflator attachment member before forming the annular fixing portion.

FIG. 9 is a cross-sectional view showing a state in which the airbag is fixed to the inflator mounting member by forming an annular fixing portion.

FIG. 10 is a cross-sectional view showing an example of a conventional airbag device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Airbag device, 2 ... Inflator case, 3 ... Bottom wall, 5 ... Inflator, 9 ... Cylindrical part, 10 ... Airbag, 11 ... Annular reinforcing part, 13 ... Punching hole, 27 ... Annular fixing part

Claims (4)

[Claims] 1. An inflator mounting member to which an inflator is mounted, and an annular reinforcing portion is formed at the periphery of the opening. The annular reinforcing portion is fixed to the inflator mounting member so as to surround the high pressure gas injection hole of the inflator. An airbag device having an airbag, wherein the annular reinforcing portion is integrally heat-sealed to the peripheral edge of the opening portion by a molding method of a thermoplastic synthetic resin. 2. The airbag device according to claim 1, wherein a plurality of punched holes are formed at a peripheral edge of the opening portion of the airbag, and the thermoplastic resin forming the annular reinforcing portion is filled in the punched holes. 3. An air bag apparatus comprising: an inflator mounting member to which an inflator is mounted; and an air bag fixed to the inflator mounting member so as to surround a high pressure gas injection hole of the inflator at a peripheral edge of the opening. A plurality of punched holes are formed on the periphery of the opening of the bag, and the airbag is integrally heat-sealed to the surface of the airbag, the punched hole and the surface of the insulator mounting member by a molding method of thermoplastic synthetic resin. An air bag device, wherein the air bag device is fixed to the inflator mounting member via a fixed annular fixing portion. 4. The inflator mounting member according to claim 3, wherein a concave portion is formed on the surface of the inflator mounting member, and the thermoplastic synthetic resin forming the annular fixing portion is integrally heat fused to the concave portion. Airbag device.