JPH0971207A - Mounting structure of steering wheel provided with air bag mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance design and secure stability at the time of expansion of an air bag. SOLUTION: A steering wheel 1 is provided with a boss plate 3, a ring part core 7, a spoke part core 8 and a steering wheel main body 4, etc., including a cover body 9 and a pad part 13. The pad part 13 is formed in one body with the cover body 9. An air bag mechanism 17 provided with an inflator 21, an air bag 22 and a bag holder 23, etc., is provided between the boss plate 3 and the pad part 13. A bolt 28 is screwed up in such a state that the bolt hole of the projecting part 25 of the bag holder 23 and the screw hole of the connection part 8 of the spoke part core 8 meet each other in their positions so that the bag holder 23 may be fixed. When a specific shock is applied, the air bag 22 expands but since the bag holder 23 is fixed against the spoke part core 8 made of metal, the bag holder 23 can be securely held in its non-movable state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle steering wheel, and more particularly to a steering wheel having a cover and a pad portion integrally formed therein and having an airbag mechanism inside. It relates to a mounting structure.

[0002]

2. Description of the Related Art Conventionally, as this type of technique, for example, one disclosed in Japanese Patent Laid-Open No. 2-133955 is known. In this technique, as shown in FIG. 6, a boss plate 52 is attached to the steering shaft 51.
An airbag mechanism 56 including an inflator 53 containing a gas generating agent, an airbag 54, a bag holder 55 for holding and fixing these 53, 54, and the like is disposed in the central portion on the upper side of the boss plate 52. Has been done. Also,
A steering wheel body 57 is attached to the boss plate 52 so as to cover the airbag mechanism 56. The steering wheel main body 57 includes a metal ring portion core metal 58, a spoke portion core metal 59 extending from the ring portion core metal 58 toward the center, a cover 61 made of polyurethane or the like for covering these, and a pad portion 62. Is equipped with. The pad portion 62 has the airbag mechanism 56.
Is located in the substantially central portion of the steering wheel main body 57 above and is made of polyurethane or the like like the cover 61. Further, in this technique, the pad portion 62 is integrally formed so as to be continuous with the covering body 61.

As described above, since the pad portion 62 is continuously and integrally formed with the cover 61, the parting line on the upper surface side of the steering wheel is eliminated and the design is improved. In addition, it is possible to reduce the number of molding steps, and it is possible to reduce the overall manufacturing cost.

Further, in this technique, when a predetermined impact force is applied, gas (for example, nitrogen gas) is generated from the inflator 53 and the airbag 54 is inflated. And
The pad portion 62 is expanded by the airbag 54, and the airbag 54 is further expanded from the steering wheel.

[0005]

However, in the above-mentioned technique, the bag holder 55 for holding and fixing the inflator 53 and the airbag 54 has the covering body (the portion referred to as a covering layer in the publication) of the steering wheel body 57. ) Was fixed at 61. The cover 61 is generally made of resin. Therefore, when gas is generated from the inflator 53, the stress transmitted from the inflator 53 and the airbag 54 may make it impossible to secure the holding and fixing state of the bag holder 55.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to improve the design and to securely hold and fix an air bag and the like. It is an object of the present invention to provide a steering wheel mounting structure capable of ensuring stability during expansion.

[0007]

In order to achieve the above object, in the invention described in claim 1, a boss plate mounted on a steering shaft, a ring core metal,
A spoke core bar extending from the ring core bar toward the center, a covering body covering the spoke core bar, and a pad portion located substantially at the upper center and integrally formed with the cover core, and at least the spokes. A part of the core metal is attached to the boss plate by a fastener, a steering wheel body, a gas generator provided between the boss plate and the pad, and expanded by gas generated from the gas generator. A steering wheel mounting structure including an airbag for expanding the pad portion, and an airbag mechanism having a bag holder for holding and fixing the gas generator and the airbag, wherein the bag holder comprises: The gist is that it is fixed to the spoke core.

According to the above construction, since at least a part of the spoke portion core metal is attached to the boss plate by the fastener, the rotation of the ring portion core metal of the steering wheel body causes the spoke portion core metal and the boss to rotate. It is transmitted to the steering shaft through the plate. Further, in the present invention,
A cover body that covers the ring core metal and the spoke core metal,
The pad portion located substantially above the center is integrally formed. Therefore, the parting line on the upper surface side of the steering wheel is eliminated, and the appearance can be improved.

Further, according to the present invention, when a predetermined acceleration is applied to the vehicle, gas is instantaneously generated from the gas generator, and the air bag is inflated by the gas. And
The pad part expands and the airbag bulges from the steering wheel. At this time, the air bag and the gas generator are held and fixed to the bag holder, but the bag holder is fixed to the metal spoke core. Therefore, the bag holder is securely held in the immovable state, and by extension, the airbag and the gas generator are held in a stable state.

According to the second aspect of the invention,
A boss plate attached to the steering shaft,
A ring portion core metal, a spoke portion core metal extending from the ring portion core metal toward the center, and a covering body that covers these, and a pad portion that is located substantially at the center upper portion and is integrally formed with the covering body. In addition, at least a part of the spoke core metal is attached to the boss plate by a fastener, a gas generator provided between the boss plate and the pad portion, and a gas generator generated from the gas generator. A structure for mounting a steering wheel including an airbag mechanism having an airbag for expanding the pad portion by expanding the gas, the gas generator being fixed to the spoke core bar. That is the point.

According to the above structure, the bag holder is omitted, that is, the gas generator is directly fixed to the spoke core metal. However, also in the present invention, the airbag and the gas generator are held in a stable state when the airbag is inflated.

In the present specification, the up-down direction refers to the direction along the axial direction of the steering shaft,
It does not refer to the actual vertical direction. Therefore, the upper side refers to the direction away from the base end of the steering shaft.

[0013]

As described above, according to the steering wheel mounting structure of the present invention, the designability can be improved, and the airbag and the like can be securely held and fixed, so that the airbag is stable when inflated. It has an excellent effect of ensuring the property.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments embodying the present invention will be described below with reference to FIGS. As shown in FIG. 1, the steering wheel 1 is rotatably provided at a tip end portion of a steering shaft 2 with the shaft 2 as an axis. The steering wheel 1 includes a boss plate 3, a steering wheel body 4, and a lower cover (not shown) attached to a lower peripheral edge of the boss plate 3.

More specifically, the metal boss plate 3 is fitted into the front end portion of the steering shaft 2, which is also serrated, at a portion of the serrated insertion hole 5 located in the substantially central portion thereof. ing. Further, the upper part thereof is further tightened with the nut 6. By this tightening, the boss plate 3
Are integrally rotatably attached to the steering shaft 2.

Further, the steering wheel body 4 has a ring-shaped core metal 7 made of die-cast aluminum, a spoke core metal 8 extending from the ring core metal 7 toward the center, and a polyurethane coating covering these. It has a body 9. Then, the ring portion 1 gripped by the driver
1 is composed of a core metal bar 7 and a covering body 9,
The spoke portion 12 for transmitting the rotation of the ring portion 11 to the boss plate 3 is composed of a spoke core metal 8 and a cover 9.

Further, the steering wheel body 2 is
It also has a pad portion 13 located substantially above the center thereof. The pad portion 13 is made of polyurethane like the covering body 9 and is formed integrally with the covering body 9. Therefore, in the present embodiment, on the upper surface side of the steering wheel 1, the parting line at the boundary between the cover 9 and the pad portion 10 is eliminated, and the appearance is improved.

The front end portion of the spoke core metal 8 and the end edge portion of the boss plate 3 are attached to each other by a bolt 14 as a fastener. By this attachment, the steering wheel body 4 is attached to the boss plate 3. More specifically, a screw hole 15 is formed at each tip of the spoke core metal 8. On the other hand, bolt holes 16 are formed in the boss plate 3. Then, with the bolt hole 16 and the screw hole 15 aligned, the bolt 14 having the screw portion 14a and the head portion 14b is screwed.

Now, in the present embodiment, the boss plate 3
The air bag mechanism 17 and the horn switch mechanism 18 are provided between the pad portion 13 and the pad portion 13. The airbag mechanism 17 includes an inflator 21, which is a gas generator having a gas generating agent housed therein, a cloth airbag 22, a ring-shaped flat bag holder 23, and the like. FIG.
As shown in FIGS. 3 to 3, the peripheral portions of the airbag 22 and the inflator 21 are held and fixed to the bag holder 23 by bolts (not shown).

Further, the spoke core metal 8 is provided with a connecting portion 8a for connecting the tip portions of the adjacent core metals 8. Then, the bolt 28 is screwed in a state where the bolt hole 26 of the projecting portion 25 of the bag holder 23 and the screw hole 27 of the connecting portion 8a of the spoke core metal 8 are aligned with each other (in the present embodiment, in the present embodiment). (3 places). By this screwing, the bag holder 23 is fixed to the spoke core metal 8.
The horn switch mechanism 18 includes a known membrane switch 29, a relay unit (not shown), and the like.

Next, the operation and effect of this embodiment will be described. In the present embodiment, the pad portion 13 and the covering body 9 are continuously and integrally formed of polyurethane. Therefore, on the upper surface side of the steering wheel 1, there is no parting line at the boundary between the cover 9 and the pad portion 13. As a result, the appearance becomes good, and the designability can be improved. In addition, by integrally molding the cover 9 and the pad portion 13, it is possible to reduce the number of steps related to molding. Therefore, the cost can be reduced.

Furthermore, in the present embodiment, when a predetermined impact is applied, gas is instantaneously generated from the inflator 21, and the gas inflates the airbag 22. Then, the pad portion 13 expands and the airbag 22 bulges from the steering wheel 1. At this time, the airbag 22 and the inflator 21 are held and fixed to the bag holder 23, but the bag holder 23 is fixed to the spoke core metal 8 made of metal. For this reason,
Even if the stress due to the bulge is applied to the bag holder 23, the bag holder 23 is securely fixed in an immovable state, and thus the airbag 22 and the inflator 21 are held in a stable state. As a result, it is possible to avoid the occurrence of troubles due to the displacement of the bag holder 23, and thus to ensure the stability of the airbag 22 when inflated.

Further, in the present embodiment, the spoke core metal 8 is provided with the connecting portion 8a, and the bag holder 23 is fixed to the connecting portion 8a. Therefore, a stable fixing force can be secured even when the number of screwed portions (three in the present embodiment) is smaller than the number of spokes 12 (four in the present embodiment). As a result, workability at the time of mounting can be improved and cost can be reduced.

The present invention is not limited to the above embodiment, but may be configured as follows, for example. (1) In the above-described embodiment, the inflator 21, the airbag 22, the bag holder 23 and the like constitute the airbag mechanism 17. On the other hand, as shown in FIGS. 4 and 5, the bag holder may be omitted.
That is, the airbag mechanism 31 may be composed of an inflator 32 and an airbag 33, and these 32, 33 may be directly fixed to the spoke core metal 8 (or the connecting portion 8a). Even with such a configuration, the same operational effects as those of the above-described embodiment can be obtained.

(2) In the above embodiment, the bolts 14, 24 and 28 are used for fastening and fixing the respective members, but screws, rivets or the like may be used. (3) In the above embodiment, the case where the membrane switch 29 is used for the horn switch mechanism 18 has been embodied.
You may make it employ | adopt the switch mechanism conventionally used.

(4) In the above embodiment, the boss plate 3 is fitted to the tip portion of the steering shaft 2, and the nut 6 is tightened from the upper portion of the steering shaft 2 to attach the boss plate 3 to the steering shaft 2. Alternatively, the boss plate 3 may be fixed to the steering wheel body 4 in advance, and the integrated boss plate 3 may be attached to the steering shaft 2 by using an adapter or the like (for example, Japanese Patent Laid-Open No. 63-63). -1
34368, Japanese Utility Model Publication No. 2-24691, Japanese Utility Model Publication No. 5-2388).

(5) In the above embodiment, the spoke core metal 8 is provided with the connecting portion 8a, and the bag holder 23 is fixed to the connecting portion 8a.
The bag holder 2 is attached to the spoke core metal 8 itself without providing a.
3 may be fixed.

The technical ideas that are not described in each claim of the claims but can be grasped from the above embodiment will be described below together with their effects. (A) In a steering wheel mounting structure having an airbag mechanism according to any one of claims 1 and 2, a spoke core metal is provided with a connecting portion for connecting the spoke core metal, and The bag holder or the gas generator is fixed. With such a structure, a stable fixing force can be secured even when the number of fixing parts is relatively small, and, in turn, workability at the time of mounting and cost reduction can be achieved. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a steering wheel mounting structure according to an embodiment.

FIG. 2 is an exploded perspective view of a steering wheel as seen from below.

FIG. 3 is a partial perspective view showing a spoke mandrel.

FIG. 4 is a sectional view of another embodiment.

FIG. 5 is an exploded perspective view showing a state in which a steering wheel according to another embodiment is viewed from below.

FIG. 6 is a cross-sectional view showing a steering wheel and the like in a conventional technique.

[Explanation of symbols]

1 ... Steering wheel, 2 ... Steering wheel shaft, 3 ... Boss plate, 4 ... Steering wheel body, 7 ... Ring core metal, 8 ... Spoke core metal, 9 ...
Covers, 13 ... Pads, 14 ... Bolts as fasteners, 17, 31 ... Airbag mechanisms 21, 32 ... Inflators as gas generators, 22, 33 ... Airbags.

Claims (2)

[Claims] A boss plate (3) attached to a steering shaft (2), a ring core metal (7), a spoke core metal (8) extending from the ring core metal (7) toward the center, and A cover (9) for covering them, and a pad portion (13) located substantially at the upper center and integrally formed with the cover (9) are provided, and at least the spoke core metal (8) is provided. A steering wheel body (4), a part of which is attached to the boss plate (3) by a fastener (14), and a gas generator (provided between the boss plate (3) and the pad portion (13) ( 21), the gas generator (21)
The pad portion (13) is expanded by the gas generated from the
An air bag mechanism (1) having an air bag (22) for expanding the air bag and a bag holder (23) for holding and fixing the gas generator (21) and the air bag (22).
7) A steering wheel mounting structure comprising: an airbag mechanism, wherein the bag holder (23) is fixed to the spoke core metal (8). Mounting structure. 2. A boss plate (3) attached to a steering shaft (2), a ring mandrel (7), a spoke mandrel (8) extending from the ring mandrel (7) toward the center, and A cover (9) for covering them, and a pad portion (13) located substantially at the upper center and integrally formed with the cover (9) are provided, and at least the spoke core metal (8) is provided. A steering wheel body (4), a part of which is attached to the boss plate (3) by a fastener (14), and a gas generator (provided between the boss plate (3) and the pad portion (13) ( 32) and the gas generator (3
It is expanded by the gas generated from 2) and the pad part (1
3) A mounting structure of a steering wheel, comprising: an airbag mechanism (31) having an airbag (33) for expanding the steering wheel, wherein the gas generator (32) is the spoke core metal (8).
A steering wheel mounting structure having an airbag mechanism, which is fixed to the.