JPH11105657A - Air bag device-integrated steering wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air bag device-integrated steering wheel that has a novel structure for spreading its air bag cover. SOLUTION: A steering wheel 10 holds an air bag device in its wheel pad 12 serving also as the cover of the air bag device. The pad 12 is molded out of resin integrally together with spokes 13 and is formed in its internal wall surface with thin wall grooves 15. Upon an inflation of the air bag, the pad 12 tears along the grooves 15 into sections, which are bent on their positions continued to the spokes 13. The grooves 15 are, concretely, extended in the internal wall surface of the pad 12 from the substantial center point to the middle positions on the edge between adjacent spokes 13 so that the number of the tear sections equals that of the spokes 13. The steering wheel 10 is further formed with hinge parts at its positions continuing between the pad 12 and the spokes 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device integrated steering wheel in which an airbag device is integrated with a steering wheel, and more particularly to a bag for an airbag device when a resin is injected into a steering wheel. The present invention relates to a resin cover that is integrally formed with a resin at a central portion (wheel pad portion) of a steering wheel.

[0002]

2. Description of the Related Art In order to protect a driver in the event of a collision of an automobile, a steering wheel provided with an airbag device at a central portion (wheel pad portion) is provided.

[0003]

SUMMARY OF THE INVENTION The present invention relates to a steering wheel integrated with such an airbag device.
It is an object of the present invention to provide a device having a novel airbag cover deployment structure.

[0004]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention comprises a ring portion,
A steering wheel having a wheel pad portion, a plurality of spoke portions, and an airbag device housed in a wheel pad portion functioning as a cover of the airbag device, wherein the wheel pad portion is continuously integrated with the spoke portion. In addition to being molded with resin, a thin groove is formed on the inner wall surface of the wheel pad, and when the airbag is inflated,
The wheel pad portion is divided into a plurality of broken pieces along the thin-walled groove portion, and the broken pieces are bent at a portion continuous with the spoke portion.

Here, the steering wheel includes a ring portion, a wheel pad portion forming a central portion of the steering wheel, and a plurality of spoke portions connecting the ring portion and the wheel pad portion. The wheel pad portion is continuously and integrally resin-molded with a thermoplastic elastomer resin or a urethane foam resin that covers the ring portion and the spoke portion, and functions as a cover of an airbag device incorporated in a steering wheel. The thin groove formed on the inner wall surface of the wheel pad is
This is for facilitating breakage of the wheel pad portion when the airbag is inflated and deployed, and may be formed in a concave groove shape.
In this thin groove portion, the groove depth may be all the same, or the groove depth may be gradually changed or partially varied.

According to a second aspect of the present invention, in addition to the first aspect of the present invention, the edge of the wheel pad portion at the intermediate portion of each of the spoke portions adjacent to the thin groove portion substantially adjacent to the inner wall surface of the wheel pad portion. In this case, the number of broken pieces is made equal to the number of spoke portions, and a hinge portion is formed at a continuous portion between the wheel pad portion and the spoke portion.

Here, the hinge portion may be formed by providing a difference in the thickness of the continuous wheel pad portion and the spoke portion, or may be formed on the outer wall surface of the continuous wheel pad portion and the spoke portion. What is necessary is just to comprise by forming a concave groove.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an exploded perspective view of an essential part of an airbag device integrated steering wheel according to the present invention, FIG. 2 is a longitudinal sectional view, FIG. 3 is an enlarged sectional view of an essential part of a wheel pad part, and FIG. 4 is a first embodiment of the present invention. Front view of the form, FIG. 5
Is a front view of the second embodiment, FIG. 6 is a front view of the third embodiment, and FIG. 7 is a cross-sectional view of a state where the airbag is inflated.

Reference numeral 10 denotes a steering wheel. The steering wheel 10 includes a ring portion 11, a wheel pad portion 12 forming a central portion of the steering wheel 10, and a plurality of spoke portions 13, 13,... Connecting the ring portion 11 and the wheel pad portion 12. .

The ring portion 11 and the spoke portions 13, 13,... Are covered with a core metal covering portion 14 formed of a thermoplastic elastomer resin or a urethane foam resin. The wheel pad section 12 is formed integrally with the cored bar covering section 14 continuously. Wheel pad part 1
2 functions as a cover of an airbag device incorporated in the steering wheel 10.

On the inner wall surface of the wheel pad portion 12, a thin groove portion 15 is formed in a concave groove shape in order to easily break the wheel pad portion 12 when the airbag 20 is inflated and deployed. The thin groove portion 15 is formed so as to cross the wheel pad portion 12 from a substantially central portion of the wheel pad portion 12 to an edge portion of the wheel pad portion 12 at an intermediate portion between the adjacent spoke portions 13, 13. is there.

When the airbag 20 is deployed, the wheel pad portion 12 is torn along the thin groove portion 15 and a plurality of broken pieces 1 corresponding to the number of spoke portions 13, 13,.
Breaks down into 6,16 ... These fragments 16
It bends near the portion where the wheel pad portion 12 and the spoke portion 13 are continuous.

In order to facilitate the bending of the broken pieces 16, a hinge portion 17 may be formed in the vicinity of a continuous portion between the wheel pad portion 12 and the spoke portion 13. This hinge part 1
7 may be formed, for example, by providing a difference in the thickness of the continuous wheel pad portion 12 and the spoke portion 13. In addition, a continuous wheel pad unit 1
It may be configured by forming a concave groove 17 ′ in the outer wall surface of the portion between the spoke portion 2 and the spoke portion 13.

FIG. 4 shows four steering wheels 10 each having a spoke portion 13. In this case, the thin groove portion 15 is formed to have a cross shape. FIG. 6 shows that the spoke portion 13 has three steering wheels 10.
In this case, the thin groove portion 15 is formed so as to have a radial shape between the spoke portions 13. When the thin groove portion 15 is formed in this manner, the fragment 16
Are divided according to the number of spoke portions 13, 13,....

In the above description, it is assumed that all of the thin groove portions 15 have the same groove depth. However, in order to facilitate initial breakage, the groove depth is gradually changed,
The groove depth may be changed, for example, by partially changing the groove depth.

As shown in FIG. 5, when the thin groove 15 is formed in the front-rear direction of the vehicle body, the thin groove 15 formed in the front-rear direction of the vehicle body is broken, and a portion of the airbag 20 which comes into contact with the occupant's head or abdomen. Can be developed quickly.

The airbag 20 is formed by sewing outer edges of two circular base materials. Airbag 20
Has an opening 21 formed at the center of the base material for inserting the head of the inflator 40. In addition, this opening 2
A plurality of mounting holes 22, 22... The airbag 20 is used by being folded.

Reference numeral 30 denotes a retainer for sandwiching the airbag 20 with the inflator 40. A through hole 31 is formed in the center of the retainer 30 for inserting the head of the inflator 40. Further, a plurality of fastening holes 32, 32,... Are formed in the peripheral portion of the through hole 31 in correspondence with the mounting holes 22, 22,.

The inflator 40 is in the form of a thin cylindrical container in which a gas generating agent is sealed, and has a plurality of gas outlets 41 formed on the side surface of the head. On the outer periphery of the inflator 40, a flange 42 is provided beside the gas ejection ports 41, 41. A plurality of through holes 43 are formed in the flange 42 in correspondence with the fastening holes 32 of the retainer 30.

Reference numeral 50 denotes a retainer 30 and an inflator 40
And a base plate for holding the airbag 20 sandwiched between the steering wheel 10 and the vehicle. To fix the inflator 40 and the like, the through holes 43 and 4 of the inflator 40 are fixed to the base plate 50.
A plurality of bolt holes 51, 51,... Are formed corresponding to. The base plate 50 is provided with mounting holes 52, 52,... For mounting the base plate 50 to the steering bottom 18.

Next, the airbag device is connected to the steering wheel 10.
A method for attaching to the device will be described. First, bolt 3
Are inserted into the fastening holes 32 of the retainer 30. The bolts 33, 33...
You may leave it.

The retainer 30 with the bolts 33 is inserted into the folded airbag 20 through the opening 21 of the airbag 20, and the bolts 33 are inserted through the mounting holes 22 of the airbag 20. I do. And
The head of the inflator 40 is inserted into the opening 21 of the airbag 20, and the bolts 33 are inserted through the fastening holes 32 of the inflator 40.

Next, the fastening holes 32 of the inflator 40,
32 are inserted through bolt holes 51, 51,... Of the base plate 50 and fastened with nuts 34, 34,. In the above, the bolts 33 and the nuts 34 have been described as the fastening means, but it is a matter of course that other fastening means such as rivets may be used.

As described above, the airbag 20 is sandwiched between the retainer 30 and the inflator 40,
The airbag 20, the retainer 30, and the inflator 40 are fixed and held on the base plate 50. The airbag device can be attached to the steering wheel 10 by fastening the base plate 50 to the steering bottom by fastening means 53 such as bolts and rivets.

In the event of a car collision, the inflator 4
0 operates to inflate the airbag 20. At this time, since the entire region of the wheel pad portion 12 functions as a cover portion of the airbag device, pressure acts on the rear surface of the wheel pad portion 12.

Since the thin groove portion 15 is formed in the wheel pad portion 12, the wheel pad portion 12 breaks along the thin groove portion 15. In addition, the thin groove 15
Is formed so as to cross the wheel pad portion 12 from the center portion of the wheel pad portion 12 to the edge portion of the wheel pad portion 12 at the intermediate portion between the adjacent spoke portions 13, 13. The part 12 includes a plurality of fragments 16, 1 corresponding to the number of the spoke parts 13, 13,.
It breaks in 6 ...

[0027] These broken pieces 16 are
Since the airbag 20 is bent and bent toward the occupant in the vicinity of a portion where the airbag 20 and the spoke portion 13 are continuous, a large space for the airbag 20 to expand is formed. FIG.
When the concave groove 17 'shown in FIG. 1 is formed, the broken piece 16 is easily bent.

Reference numeral 60 denotes a core cover that surrounds a lower portion of the airbag device attached to the steering wheel 10.

[0029]

As described above, according to the first aspect of the present invention, the broken fragments are turned back to the occupant side at a portion continuous with the spoke portion to restrict the deployment direction when the airbag bag is deployed. do not do. Since the broken fragments are supported by the spokes, they are firmly supported without scattering. Further, by adjusting the position and shape of the thin groove portion, it is possible to quickly develop a portion that contacts the abdomen or the head of the occupant.

According to the second aspect of the present invention, each of the broken pieces divided by the plurality of pieces is bent by being supported by each of the spokes, so that the broken pieces are easily bent, and the deployment performance of the airbag is excellent. Become something.

In the cover portion of the conventional airbag, the deployment direction of the airbag is restricted in the direction of the occupant by the outer shape line and the side wall. In the present invention, the airbag is moved forward (occupant side). Since the vehicle is further restrained in the up, down, left, and right (spreading) directions, it is possible to reduce the harm to the occupant.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a main part of an airbag device-integrated steering wheel according to the present invention.

FIG. 2 is a longitudinal sectional view of an airbag device integrated steering wheel.

FIG. 3 is an enlarged sectional view of a main part of a wheel pad unit.

FIG. 4 is a front view of the first embodiment of the present invention.

FIG. 5 is a front view of a second embodiment of the present invention.

FIG. 6 is a front view of a third embodiment of the present invention.

FIG. 7 is a sectional view showing a state where the airbag is inflated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Steering 11 Ring part 12 Wheel pad part 13 Spoke part 15 Thin groove part 16 Broken fragment 17 Hinge part

Claims (2)

[Claims] 1. A steering wheel having a ring portion, a wheel pad portion, and a plurality of spoke portions, wherein the air bag device is housed in a wheel pad portion functioning as a cover of the air bag device, wherein the wheel pad portion is provided. In addition to being integrally molded with the spoke part and forming a thin groove on the inner wall surface of the wheel pad part, the wheel pad part breaks into multiple fragments along the thin groove part when the airbag is inflated. The steering wheel integrated with an airbag device, wherein the broken pieces are bent at a portion continuous with the spoke portion. 2. A thin groove portion is formed from a substantially central portion of an inner wall surface of a wheel pad portion to an edge portion of a wheel pad portion at an intermediate portion between adjacent spoke portions, and the number of broken pieces is determined by the number of spoke portions. 2. The steering wheel integrated with an airbag device according to claim 1, wherein a hinge portion is formed at a portion where the wheel pad portion and the spoke portion are continuous with each other.