JPH09272391A - Cover for air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cover for an air bag which permits a horn switch to be positioned not to invade an inner air bag receiving space, requires any particular countermeasure to prevent the cover from interfering with an occupant, and of which expanding performance is ensured. SOLUTION: A cover 30 for an air bag has a mark portion 38 integrally formed on the top surface of a pad body 32, a thin sheet like horn switch 42 is integrally laid, being sandwiched closely between the mark portion 38 and the pad body 32. Then, a conventional hard pad plate for drive a switch becomes unnecessary, so that an air bag space within the pad body 32 will not be invaded. Further, the fact that no member may interfere with an occupant body to injure when the pad body 32 expands, thereby no especial countermeasure will be necessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag cover used in an airbag device provided on a steering wheel of an automobile.

[0002]

2. Description of the Related Art In an air bag device attached to a steering wheel of an automobile, the bag is inflated by gas generated from an inflator when the vehicle is rapidly decelerated and is interposed between the steering wheel and an occupant.

Here, the bag and the inflator are covered with a cover and housed inside the cover, and both are attached to the hub of the steering wheel. In addition, the cover has a thin-walled judgment part that crosses around the center part, and when the airbag device is operating (when the bag is inflated), the cover is pressed from the inside by the bag to exert a tensile force, resulting in thin-wall breakage The part is broken, and the cover is configured to expand on both upper and lower sides with this as a boundary. This allows
The bag is projected to the outside of the cover and interposed between the steering wheel and the occupant to absorb the impact of the occupant.

By the way, in such an airbag device, since the bag and the inflator are housed in the cover as described above, it is difficult to provide a horn switch of a general shape on the cover. Therefore, there is one in which a so-called membrane switch formed in the shape of a thin sheet is used as a horn switch and is provided on the cover. In a cover using this type of sheet switch, a sheet switch is provided inside, and a hard contact plate is integrally fixed inside the sheet switch. In other words, the sheet switch is arranged so as to be sandwiched between the cover and the cover integrally fixed to the inside of the cover. Thus, the seat switch can be operated by pushing the switch disposition portion of the cover from the outside.

However, in such an air bag cover, since the cover plate is arranged so as to project inside the cover, the storage space for the bag and the inflator in the cover is eroded, which is an obstacle to miniaturization. It was. In addition, when the cover is deployed when the airbag is activated, the hard pad plate is deployed and moved together with the cover, so that it is necessary to take special measures to prevent the pad plate from interfering with the body of an occupant.

[0006]

In consideration of the above facts, the present invention can provide a horn switch without eroding the internal storage space, and a special measure for preventing interference with the body of an occupant. The purpose is to obtain an airbag cover that can secure the deployment performance without need.

[0007]

An air bag cover according to the present invention is used in an air bag device provided on a steering wheel, accommodates a bag and an inflator inside, and expands by a gas generated from the inflator. A pad body that is pressurized and expanded by the bag,
A mark member formed of a soft material and exposed and integrally fixed to the front side of the pad body, and a mark formed in a sheet shape are integrally provided by being tightly sandwiched between the mark member and the pad body. And a horn switch.

In the airbag cover having the above structure, the sheet-shaped horn switch is arranged on the front side of the pad body.
The horn switch is operated by pressing the mark member.

Here, in this airbag cover, the conventional contact plate for operating the switch does not exist inside the pad body. Therefore, the internal storage space of the pad body is not eroded, and there is no obstacle to downsizing the device. Further, when the airbag is operated, the bag is projected to the outside of the pad body and is interposed between the steering wheel and the occupant, and the impact of the occupant is absorbed.
In this case, even if the pad main body is expanded due to the expansion of the bag, there is no such a hard pad, that is, a member that interferes with the body of the occupant and causes a harmful effect, so that no special measure is required.

As described above, the horn switch can be provided without eroding the internal storage space, and further, the special performance for preventing the interference with the body of the occupant is not required, and the deploying performance can be reliably ensured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the overall configuration of an airbag device 10 for a driver's seat of a vehicle to which an airbag cover 30 according to an embodiment of the present invention is applied.

In the airbag device 10, the base plate 12 is supported by the hub 16A (core metal part) of the steering wheel 16 by the bolts 14. A bag 18 and an inflator 20 are attached to the base plate 12.

The bag 18 is arranged in a folded state on the occupant side of the base plate 12 (upper side in FIG. 1). The edge of the bag 18 on the opening side is attached to a substantially central portion of the base plate 12 via a ring plate 22. The ring plate 22 is fastened to the base plate 12 with a bolt (not shown), and the edge of the opening side of the bag 18 is pressed against the base plate 12.

The inflator 20 has a cylindrical shape, and is arranged so as to penetrate the substantially central portion of the base plate 12 and be inserted into the bag 18. A flange 20A is formed on the outer periphery of the inflator 20, and is fixed to the surface of the base plate 12 on the side opposite to the occupant (lower side in FIG. 1) with a bolt (not shown). A gas generating substance is enclosed in the inflator 20, and a large amount of gas is released by burning when the vehicle rapidly decelerates. Further, a gas hole 24 is formed on the occupant side peripheral surface of the inflator 20, and the gas generated by the combustion of the gas generating agent is ejected to the bag 18. The bag 18 can be inflated by this gas.

On the other hand, a cover 30 is arranged outside the bag 18. The cover 30 includes a pad body 32 made of synthetic resin (more specifically, urethane), and the pad body 32 is on the occupant side of the base plate 12 (upper side in FIG. 1).
The bag 18 is housed between the base plate 12 and the base plate 12.

A core metal 34 is embedded in a part of the peripheral edge of the pad body 32, and the core metal 34 is used for the base plate 1.
Steering wheel 16 with bolt 14 together with 2
Is directly fixed to the hub 16A (core metal part).

Further, the pad main body 32 is formed with a thin broken portion 36, and the broken portion 36 is broken when the bag 18 is inflated.

Further, in the central portion of the pad body 32,
A mark portion 38 is provided. The mark portion 38 is made of a soft material, is exposed on the front side of the pad body 32, and has a locking projection 40 formed in a protruding manner. The locking protrusion 40 penetrates the pad main body 32 and is heat-welded on the back surface side of the pad main body 32, whereby the mark portion 38 is integrally fixed to the pad main body 32. In this case, the surface (design surface) of the mark portion 38 is the pad body 3
The shape and the like are set so as to be flush with the surface of 2.

Further, a horn switch 42 is arranged between the mark portion 38 and the pad body 32. The horn switch 42 is a so-called membrane switch formed in a sheet shape, and is integrally provided by being sandwiched between the mark portion 38 and the pad body 32 in a close contact state. A flexible cable 44 is integrally connected to the horn switch 42. The flexible cable 44 is arranged along the inner peripheral wall of the pad body 32, and then guided to the outside of the cover 30 for connection.

Next, the operation of this embodiment will be described. Airbag cover 30 (airbag device 10) having the above configuration
Then, the sheet-shaped horn switch 42 is the pad main body 32.
The horn switch 42 is operated by pressing the mark portion 38 on the front side of the.

Here, in the airbag cover 30, a pad plate for operating a switch as in the conventional case is used as the pad body 3.
It does not exist inside 2. Therefore, the internal storage space of the pad main body 32 is not eroded, and there is no obstacle when downsizing the device.

When the vehicle suddenly decelerates, the inflator 20 is actuated and gas is sent into the bag 18 to inflate the bag 18. The expansion of the bag 18 pressurizes the pad body 32 of the cover 30 from the inside, and the rupture portion 36 of the pad body 32 is ruptured by the applied pressure, and the pad body 32 is largely expanded. With the expansion of the pad body 32, the bag 18 is projected to the outside of the pad body 32 and interposed between the steering wheel 16 and the occupant, and the impact of the occupant is absorbed.

In this case, even if the pad main body 32 is expanded due to the expansion of the bag 18, there is no such a hard pad, that is, a member that interferes with the body of the occupant and is harmful.
No special measures needed.

As described above, in the airbag cover 30 according to the present embodiment, the horn switch can be provided without eroding the internal storage space, and further, a special horn switch is provided for preventing interference with the body of the occupant. No need to take any measures to ensure the deployment performance.

[0025]

As described above, in the airbag cover according to the present invention, the horn switch can be provided without eroding the internal storage space, and the special cover for preventing the interference with the body of the occupant. It has the excellent effect of ensuring the deployment performance without any measures.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an overall structure of an airbag device to which an airbag cover according to an embodiment of the present invention is applied.

[Explanation of symbols]

 10 Airbag Device 16 Steering Wheel 18 Bag 20 Inflator 30 Cover 32 Pad Body 38 Mark Part (Mark Member) 42 Horn Switch

Claims (1)

[Claims] 1. A pad body for use in an airbag device provided on a steering wheel, which accommodates a bag and an inflator inside and is expanded by being pressurized by a gas inflated by gas generated from the inflator, and a soft material. And a horn switch integrally formed by being exposed to the front side of the pad body and fixed integrally with the pad body and formed in a sheet shape and sandwiched in close contact between the mark member and the pad body. And a cover for the airbag.