JP2578456Y2 - Airbag device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device for deploying an airbag with gas injected from a gas generator to protect an occupant such as an automobile from impact.

[0002]

2. Description of the Related Art An airbag device described in, for example, Japanese Patent Publication No. 57-60166 is known.

In this airbag device, a mounting plate fixed to a steering wheel body of an automobile, a plurality of gas injection ports formed in an upper portion of an outer peripheral portion having a substantially cylindrical shape, and a flange portion is provided to project from an intermediate portion of the outer peripheral portion. A gas generator (inflator) and a bag-shaped airbag. Then, the gas generator is loosely fitted into the circular hole formed in the mounting plate, the flange portion abuts on the lower surface of the mounting plate, and the peripheral portion of the opening of the airbag is formed around the circular hole on the upper surface of the mounting plate. With the retainer, airbag, mounting plate, and bolts and nuts inserted through the through holes formed in the flanges of the gas generator tightly adhered and pressed down by the retainer, they are brought into close contact with each other, and the airbag is attached to the mounting plate. And a gas generator is installed.

[0004] Further, in such a gas generator of an airbag device, an igniter is provided at a central portion inside, and a gas generating agent (propellant) is stored in a combustion chamber provided around the igniter. A cooling filter is housed in a cooling chamber provided around the combustion chamber.

Further, in such an airbag device, a cover is provided which covers the upper side of the airbag which is always folded and stored on the mounting plate. This cover body is attached to the mounting plate by fixing the mounting piece protruding from the back side to the end of the mounting plate with a rivet or the like, and a fragile break line is formed, and the pressure of the inflation of the airbag is formed. Thereby, it is broken along this breaking line.

When the impact sensor detects the impact of a vehicle collision, the igniter operates to ignite and burn the gas generating agent to generate high-temperature, high-pressure combustion gas. Then, the combustion gas is cooled to a predetermined temperature in a process of passing through the cooling chamber and is ejected from the injection port into the airbag, whereby the airbag is rapidly expanded and deployed. Then, the cover body is broken and expanded by the pressure of the inflation of the airbag, and the airbag is projected to the occupant side.

[0007]

During operation of the airbag apparatus having the above-mentioned conventional structure, the gas generator is heated to a high temperature with the combustion of the gas generating agent, and the high heat of the gas generator is attached via the flange portion. Conduction to the plate and further from the end of the mounting plate to the mounting piece of the cover body. Therefore, in order to prevent the mounting piece of the cover body from being deteriorated or melted by heat when the airbag device is operated, the mounting piece of the cover body is made of a material having high heat resistance such as urethane, or the mounting piece of the mounting piece is made of urethane. There is a problem that it is necessary to form the cover in a large thickness, and the material and shape of the cover are limited.

[0008] The present invention has been made in view of such a point, and it is possible to increase the degree of freedom in the material and shape of a cover body for covering an airbag, and to improve the airbag.
An object of the present invention is to provide an airbag device that can inflate and deploy efficiently .

[0009]

According to the present invention, there is provided an airbag apparatus comprising: a mounting member having a gas generator mounting hole ;
A gas generator attached to the mounting body through a device mounting hole, an airbag into which gas injected from the gas generator flows and deploys, and an airbag attached to the mounting body at all times. An airbag device having a cover body for covering the gas generator mounting hole at a contact portion between the mounting body and the gas generator;
A heat insulator sandwiched between and attached to the attachment and the gas generator is interposed.

[0010]

According to the airbag device of the present invention, in the airbag device in which the gas generator and the cover body covering the airbag are mounted on the mounting body, a heat insulator is interposed at the contact portion between the mounting body and the gas generator. Therefore, conduction of high heat generated during operation of the gas generator from the gas generator to the cover body via the attachment body is suppressed. Also, the heat insulator is inserted with a gas generator.
Around the gas generator mounting hole through which
Injected from a gas generator as it is sandwiched and tightly attached to the creature
Gas leaks from the contact point between the gas generator and the mounting body
Is suppressed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an embodiment of the airbag device of the present invention will be described below with reference to the drawings.

In FIG. 2, reference numeral 11 denotes a main body of a steering wheel of an automobile.
The boss 12 includes a central boss 12, an annular rim 14, and a plurality of spokes 15 connecting the boss 12 and the rim 14.

As shown in FIG. 3, a metal cylindrical boss 21 fitted to a steering shaft (not shown) is provided below the boss portion 12 (on the vehicle side).
The fixing part 22 is fixed to the upper part of the upper part by welding or the like. The metal core 15a of the spoke portion 15 is fixed to the fixing portion 22 by welding or the like. The fixed portion 22 is provided with a pair of fixed contact portions on both sides constituting a horn switch device (not shown), and a pair of horn plates 24 on both sides provided with a movable contact portion which comes into contact with and separates from these fixed contact portions. It is elastically supported above and below the contact portion so as to be vertically movable.
A support piece 25 projects downward from each horn plate 24, and a through hole 25a formed in each support piece 25 is formed.
The nut body 26 is fixedly attached to the nut.

An airbag device 27 is mounted above the boss 12 (occupant side).

This airbag device 27 is shown in FIGS.
As shown in FIG. 2, a base plate 31 is provided as a mounting body having a substantially rectangular shape in a plane, and a gas generator mounting hole 32 is formed at a substantially central portion of the base plate 31, and around the gas generator mounting hole 32, A plurality of large and small through holes 33a, 33b are formed. The end of the base plate 31 is bent downward to form a cover mounting portion having a plurality of through holes 35a.
35 are formed. Further, a pair of L-shaped cross-section brackets 37 each having a mounting hole 37a are fixed to the lower surface of the base plate 31.

Reference numeral 38 denotes a substantially rectangular plate-shaped heat insulator. The heat insulator 38 is formed of a resin or a metal fiber having a low thermal conductivity and a high airtightness, and is attached to the lower surface of the base plate 31 in close contact therewith. Have been. The heat insulator 38 is formed with a fitting hole 39 which is concentric with the gas generator mounting hole 32 of the base plate 31 and has a slightly smaller diameter, and a plurality of through holes 40 communicating with the respective through holes 33a of the base plate 31. Is formed.

Reference numeral 41 denotes a gas generator (inflator)
The gas generator 41 has a substantially cylindrical main body 43 and a flange 44 projecting from the outer peripheral surface of the main body 43. Then, with the flange portion 44 in close contact with the lower surface of the heat insulator 38, the upper portion of the main body portion 43
And protrudes above the base plate 31 through the gas generator mounting hole 32 of the base plate 31.

An igniter is provided inside the main body 43, for example, at the center thereof, and a combustion chamber is provided around the igniter and contains a gas generating agent (propellant).
A cooling chamber containing a cooling filter is provided in communication with the periphery of the combustion chamber, and the cooling chamber is communicated with the outside through a plurality of gas injection ports 45 formed on the outer peripheral surface of the main body 43. ing. The flange portion 44 of the gas generator 41 has substantially the same shape as the heat insulator 38, and has a through hole 44a communicating with each through hole 40 of the heat insulator 38.

Reference numeral 51 denotes a bag-shaped airbag. The airbag 51 is normally housed in a folded state above the base plate 31 and has substantially the same shape as the gas generator mounting hole 32 of the base plate 31. The opening 52 is formed, and the periphery of the opening 52 is attached to the upper surface of the base plate 31 in a state where the opening 52 communicates with the gas generator mounting hole 32 of the base plate 31. In the periphery of the opening 52, the through holes 33a of the base plate 31 are provided.
A plurality of large and small through holes 51a, 51b communicating with 33b are formed.

Further, the periphery of the opening 52 of the airbag 51 is held between and tightly attached to the upper surface of the base plate 31 by a substantially annular pressing ring (retainer) 55. The holding ring 55 is formed with a slightly larger circular hole 56 which is substantially concentric with the gas generator mounting hole 32 of the base plate 31, and which is flanged upward from the peripheral edge and the outer peripheral portion of the circular hole 56, respectively. Portion 57 is formed and a circular hole
A plurality of through-holes 55a, 55b communicating with the through-holes 51a, 51b of the airbag 51 are formed in the periphery of the 56.

The press ring 55 and the airbag
51 and the base plate 31 each have a small-diameter through hole 55b.
, 51b, 33b are integrally connected and held by a rivet (not shown) through which the pressing ring 55, the airbag 51, the base plate 31, the heat insulator 38, and the gas generator 41 have large-diameter through holes. 55a, 51a, 33a, 4
The nuts 58b are screwed into the stud bolts 58a fixed to the holding ring 55 by welding or the like, and the nuts 58a are integrally connected and held.

Reference numeral 61 denotes a substantially box-shaped cover body having an open lower surface. The cover body 61 is made of urethane, elastomer, or the like, and has a plate-like shape from the vicinity of the rear-side end of the upper surface portion 62 facing the occupant. The mounting pieces 64 are projected downward, and these mounting pieces 64 are attached to the cover mounting portions of the base plate 31.
In the state of fitting and abutting on the outside of the base plate 35, the base plate 31 is connected to the through hole 64a formed in each mounting piece portion 64 and the rivet 65 inserted through the through hole 35a formed in the cover body mounting portion 35 of the base plate 31. They are integrally connected and held.

The cover body 61 always covers the upper side of the airbag 51 folded and stored on the base plate 31. When the airbag 51 is inflated, the pressure of the inflation causes a fragile break (not shown). It breaks along the line.

The airbag device 27 having the above-described structure is provided with a mounting screw 68 inserted through the mounting hole 37a of the bracket 37 fixed to the lower surface of the base plate 31 and a horn plate provided on the steering wheel body 11 side. Nut body fixed to through hole 25a formed in support piece 25 of 24
It is mounted on the upper part of the boss portion 12 of the steering wheel body by screwing it into 26.

Next, the deployment operation of the airbag device 27 of this embodiment will be described.

In the event of an automobile collision, an impact sensor (not shown) detects the impact and activates the igniter of the gas generator 41. The igniter ignites the gas generating agent in the combustion chamber and burns to generate high-temperature and high-pressure combustion gas.
This combustion gas is cooled to a predetermined temperature in the process of passing through the cooling chamber, is injected into the airbag 51 from the gas injection port 45, and rapidly expands and deploys the airbag 51. The pressure of the inflation of the airbag 51 causes the cover
Break the air bag 61 along the break line and deploy it.
To the occupant side.

According to the airbag device 27 of this embodiment, in the airbag device 27 in which the gas generator 41 and the cover body 61 that covers the airbag 51 are mounted on the base plate 31, the base plate 31 and the gas generator 41 Since the heat insulator 38 having low thermal conductivity is interposed in the contact portion with the gas generator 41, the gas generator 41
The high heat generated during the operation of the gas generator 41
From the mounting piece 64 of the cover body 61 via the base plate 31
Can be suppressed. Therefore, the cover body 61 can be formed of, for example, an elastomer having lower heat resistance than urethane, or the thickness of the mounting piece 64 of the cover body 61 can be reduced, and the cover body 61 that covers the airbag 51 can be formed.
The degree of freedom such as the material and shape of the material can be increased.

Further, the heat insulator 38 is formed of a highly airtight material, and the flange portion 44 of the gas generator 41 and the base plate 31 are formed.
The gas bag 41 is attached in close contact with the lower surface, so that the gas injected from the gas generator 41 is prevented from leaking downward from the contact portion between the gas generator 41 and the base plate 31, and the airbag 51 is efficiently mounted. Can be expanded and expanded.

Next, another embodiment of the present invention will be described.

The airbag device 71 of this embodiment is directed upward from the periphery of a fitting hole 73 provided at the center instead of the heat insulator 38 used in the airbag device 27 shown in FIGS. In this case, a heat insulator 75 in which a cylindrical portion 74 is integrally protruded is used. By using such a heat insulator 75 and bringing the cylindrical portion 74 into close contact with the main body 43 of the gas generator 41, the gas generator 41
And the base plate 31 can further enhance the heat insulating property and airtightness of the contact portion.

Further, in this embodiment, the mounting piece 77 of the cover body 61 which is mounted in contact with the cover body mounting portion 35 of the base plate 31 is integrally provided so as to protrude from the peripheral edge of the cover body 61.

The base plate 31 of each of the above embodiments is used.
With respect to the base plate 31, the rigidity of the base plate 31 can be increased by integrally projecting a flange portion upward from the peripheral portion of the gas generator mounting hole 32 formed in the center portion. When the flange portion is formed integrally as described above, the corner portion of the flange portion becomes a curved surface, and maintaining the airtightness between the base plate 31 and the gas generator 41 becomes complicated. Three
Airtightness can be easily maintained by using 8,75.

Further, the brackets 37 joined to the lower surface of the base plate 31 can be integrally protruded from the cover attaching portions 35 located on both sides of the base plate 31.

In each of the embodiments described above, the airbag devices 27 and 71 provided on the steering wheel of the vehicle have been described. However, in the present invention, the airbag devices provided on the passenger seat side of the vehicle or the air provided on other parts are provided. It can also be applied to a bag device.

[0035]

According to the airbag device of the present invention, in the airbag device in which the gas generator and the cover covering the airbag are mounted on the mounting body, the contact portion between the mounting body and the gas generator is insulated. Since the body is interposed, it is possible to suppress high heat generated during operation of the gas generator from being conducted from the gas generator to the cover body via the mounting body. Therefore, the cover body can be formed of a material having low heat resistance, or the thickness of the portion where the cover body is attached to the mounting body can be reduced, and the degree of freedom of the material and shape of the cover body covering the airbag can be improved. Can be increased. Also, the heat insulator is a gas generator
Surround the gas generator mounting hole to be inserted, and
Since it is pinched and closely attached to the generator, it
Injected gas leaks from the contact area between the gas generator and the attachment.
Control the air bag and inflate the air bag efficiently.
Wear.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the airbag device of the present invention.

FIG. 2 is a plan view of a steering wheel provided with the airbag device.

FIG. 3 is a sectional view taken along line AA of FIG. 2 showing the airbag device.

FIG. 4 is a sectional view showing another embodiment of the airbag device of the present invention.

[Explanation of symbols]

27 Airbag device 31 Base plate as mounting body 32 Gas generator mounting hole 38 Insulation body 41 Gas generator 51 Airbag 61 Cover body

Claims (1)

(57) [Scope of request for utility model registration] 1. A a mounting body provided with a gas generator mounting hole, before
A gas generator attached to the mounting body through the gas generator mounting hole, an airbag into which gas injected from the gas generator flows and deploys, and the airbag device that includes a cover body covering the air bag, the contact portion between the gas generator and the attachment member, the gas
Surrounding the generator mounting hole, and the mounting body and the gas generation
An airbag device characterized by interposing a heat insulator sandwiched between and tightly attached to a container .