JP2610383B2 - Steering wheel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering wheel provided with an airbag device and a horn switch mechanism.

[0002]

2. Description of the Related Art Conventionally, for example, a steering wheel described in Japanese Patent Application Laid-Open No. 3-143,752 is known.

This steering wheel is provided with an airbag device on the occupant side of a boss portion of the steering wheel body. The airbag device is provided with a gas generator (inflator) and a bag-like shape stored in a folded state. , And a cover body that covers the airbag. Then, in a state where the impact sensor detects an impact such as an automobile collision, a gas is rapidly injected from the gas generator into the airbag, and the airbag inflates rapidly. Further, the pressure of the inflation of the airbag causes the cover body to be formed thin, so that a break line (tea line) is formed.
, The cover body expands like a door, and a projecting opening of the airbag is formed.

In this steering wheel, a flat horn switch mechanism is insert-molded inside the cover body of the airbag device, and the contact of the horn switch mechanism is closed when the cover body is pressed. Thus, the horn mechanism is operated.

[0005]

However, when the horn switch mechanism is insert-molded inside the cover body of the airbag apparatus as in the above-mentioned conventional art, the strength of the cover body changes, so that the airbag inflates. When the cover body is unfolded, it is necessary to set the strength so that the cover body and the horn switch mechanism are not damaged at a position other than a predetermined position, and there is a problem that the manufacturing process of the cover body becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a steering wheel having an airbag device and a horn switch mechanism and capable of easily manufacturing a cover body.

[0007]

According to the present invention, there is provided a steering wheel including a steering wheel body, an airbag device, and a horn switch mechanism for operating a horn mechanism in a pushed state. The bag device includes a gas generator, an airbag housed on the occupant side of the gas generator, and a cover body that covers the airbag, and the horn is provided between the gas generator and the airbag. It has a switch mechanism.

[0008]

In the steering wheel of the present invention, when the cover is pushed, the horn switch mechanism is pushed via the cover and the stored airbag, and the horn mechanism operates. Further, when gas is injected from the gas generator into the airbag, the airbag is inflated, and the pressure of the inflation causes the cover body to break at a predetermined position and unfold, thereby forming a projecting opening of the airbag. The airbag protrudes from the spout to protect the occupant.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a steering wheel according to an embodiment of the present invention.

In FIG. 3, reference numeral 11 denotes a steering wheel body 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. 1, a substantially cylindrical boss 21 made of metal is provided below the boss portion 12 (on the vehicle body side) to be fitted to a steering shaft (not shown). A boss plate 22 is fixed to the upper portion by welding or the like. On the upper surface near the edge of the boss plate 22, a metal core 15a of the spoke portion 15 is fixed by welding or the like.

An airbag device 25 is mounted above the boss 12 (occupant side). As shown in FIGS. 1 and 2, the airbag device 25 has a mounting plate 26 having a substantially square planar shape. At a substantially central portion of the mounting plate 26, a gas generator mounting hole 27 is formed, and around the gas generator mounting hole 27, a plurality of through holes 28 are formed. The end of the mounting plate 26 is bent downward to form a cover body mounting portion 30 having a plurality of through holes 29 formed therein.

Further, a bracket (not shown) is fixed to the lower surface of the mounting plate 26, and the mounting plate 26 is fixed to the upper surface of the boss plate 22 by the bracket.

Reference numeral 33 denotes a gas generator (inflator)
The gas generator 33 has a substantially cylindrical main body 34,
It has a flange 35 protruding from the outer peripheral surface of the main body 34. Then, with the flange portion 35 in close contact with the lower surface of the mounting plate 26, the upper portion of the main body portion 34 is inserted through the gas generator mounting hole 27 of the mounting plate 26, and projects upward from the mounting plate 26. ing.

An igniter is provided, for example, in the center of the main body 34 of the gas generator 33, and a gas generating agent (propellant) is filled around the igniter. The inside of the main body 34 is communicated with the outside through gas injection ports 36 formed on the outer peripheral surface of the main body 34.
Further, a through hole 37 communicating with each through hole 28 of the mounting plate 26 is formed in the flange portion 35 of the gas generator 33, and an electric wire 38 connected to the igniter is formed from the lower surface of the main body 34. Is derived.

A horn switch mechanism 41 has a conductive retainer plate 42 that covers the upper side of the gas generator 33. The retainer plate 42 has a substantially cylindrical tubular portion 43 that covers the peripheral surface of the gas generator 33, and fixed contacts that are slightly recessed from the upper end of the tubular portion 43 and cover the upper surface of the gas generator 33. A portion 44 and a retainer portion 45 protruding from the lower end of the tubular portion 43 are formed.

A plurality of communication holes 46 communicating with the gas injection ports 36 of the gas generator 33 are formed in the cylindrical portion 43.

The retainer 45 has a plurality of through-holes 47 communicating with the respective through-holes 28 of the mounting plate 26. The end of the retainer 45 is bent upward. A reinforcing flange portion 48 is formed. Then, the bolts 51 inserted and fixed from the upper side into the through holes 47 of the retainer portion 45 are inserted into the through holes 28 of the mounting plate 26 and the through holes 37 of the flange portion 35 of the gas generator 33. By screwing a nut 52 to the lower side of the bolt 51, the gas generator 33 and the retainer plate 42 are fixed to the mounting plate 26.

On the other hand, the fixed contact portion 44 of the retainer plate 42
A plurality of horn plate mounting holes 54 are formed in the vicinity of the end, and a harness notch 55 is formed in one end of the fixed contact portion 44.

Reference numeral 61 denotes a conductive horn plate. The horn plate 61 has a substantially disk shape and is supported above the fixed contact portion 44 of the retainer plate 42 so as to be vertically movable. That is, in the horn plate 61, mounting holes 62 are formed so as to face the horn plate mounting holes 54 of the fixed contact portion 44. Insulating insulators 63 and 64 are respectively formed in these mounting holes 62 from above and below. It is fitted. Each of the insulators 63 and 64 has a cylindrical shape, and has flanges 63a and 64a protruding from an upper end thereof, and these flanges 63a and 64a are connected to the horn plate 61.
Abut on the upper and lower surfaces.

Then, with the coil-shaped spring body 66 disposed between the lower insulator 64 and the fixed contact portion 44 of the retainer plate 42, the mounting bolt 67 is inserted into the through hole of the upper insulator 63 from above. And this mounting bolt
The horn plate 61 is screwed into the horn plate mounting hole 54 of the fixed contact portion 44 of the retainer plate 42 so that the horn plate 61
Are elastically supported to be vertically movable while being insulated from the retainer plate.

A plurality of movable contact portions 68 are bent downward from a plurality of end portions of the horn plate 61, and downwardly from a substantially central portion of the horn plate 61. The terminal piece mounting portion 69 is formed by being cut and raised. A conductive terminal strip 71 is mounted on the terminal strip mounting section 69, and the horn plate 61 is electrically connected to a slip ring (not shown) via a horn harness 72 connected to the terminal strip 71. Connected. The horn harness 72 is attached to the retainer plate 42
Through the through hole 51a formed in the notch portion 55 for harness and the shaft of the bolt 51, it is led to the lower side of the airbag device 25, and from the vicinity of the terminal piece 71 to the vicinity of the bolt 51, It is covered by a tubular cover body 73.

Further, reference numeral 75 denotes a bag-shaped airbag, which is normally folded over the mounting plate 26 so as to cover the gas generator 33 and the retainer plate 42. It is stored in.

The airbag 75 has an opening 76 formed substantially in the same shape as the gas generator mounting hole 27 of the mounting plate 26. The opening 76 communicates with the gas generator mounting hole 27. In this state, the peripheral portion of the opening 76 is sandwiched between the upper surface of the mounting plate 26 and the retainer portion 45 of the retainer plate 42 so as to be closely attached thereto.

Further, reference numeral 81 denotes a substantially box-shaped cover body having an open lower surface. The cover body 81 is made of urethane or elastomer, and always has a mounting plate.
26 covers the upper side of the airbag 75 which is folded and stored. A plate-like mounting piece 83 is projected downward from near the rear end of the upper surface 82 facing the occupant, and these mounting pieces 83 are attached to the cover body mounting section 30 of the mounting plate 26. Are fixed by rivets (not shown) in a state of fitting and abutting on the outside. further,
On the back side of the upper surface 82 of this cover body 81, a fragile breaking line
85 is formed in a substantially H-shaped plane.

The rim portion 14, the spokes 15, and the boss portion 12 of the steering wheel body 11 which are not covered by the cover body 81 are integrally covered with a skin material 87 made of a soft synthetic resin or the like. The lower side of the boss 12 is covered with a lower cover 88.

In the above structure, the cover 81
When the central portion of the upper surface portion 82 is pushed, the horn plate 61 of the horn switch mechanism 41 is pushed downward via the cover body 81 and the folded and stored airbag 75. And the movable contact portion 68 of the horn plate 61,
With the fixed contact portion 44 of the retainer plate 42 in contact with the contact, the horn mechanism operates and the horn is blown.

In the event of an automobile collision or the like, an impact sensor (not shown) detects the impact and activates the igniter of the gas generator 33. The igniter ignites and burns the gas generating agent to generate high-temperature and high-pressure combustion gas. This combustion gas is injected into the airbag 75 from the gas injection port 36, and the airbag 75 is rapidly expanded and deployed.
Then, due to the pressure of the inflation of the airbag 75, the upper surface portion 82 of the cover body 81 is broken along a breaking line 85, and the upper surface portion 82 is developed in a door shape to form a projecting opening of the airbag 75. . The airbag 75 projects from the projecting opening to protect an occupant.

According to the airbag device 25 of the present embodiment, the horn switch mechanism 41 including the fixed contact portion 44 and the movable contact portion 68 is connected to the folded and stored airbag 75 and the gas generator 33. Since the horn switch mechanism 41 does not affect the deployment of the airbag 75 and the cover 81, the production of the cover 81 can be facilitated.

Further, since the fixed contact portion 44 is formed integrally with the retainer plate 42 for holding the airbag 75, an increase in the number of components can be suppressed.

In the above embodiment, the horn plate 61 is elastically supported by the coil-shaped spring body 66. However, the horn plate 61 may be supported by an elastic body such as a leaf spring material.

In each of the above embodiments, the spring body
The horn switch mechanism 41 is configured such that the fixed contact section 44 and the movable contact section 68 are opposed to each other via the 66 or the like. However, the horn switch mechanism 41 may be configured by a pressure-sensitive switch or a strain gauge.

[0033]

According to the steering wheel of the present invention, by pushing the cover body, the horn switch mechanism is pushed through the cover body and the stored airbag to operate the horn mechanism. it can. Also,
Since the horn switch mechanism is disposed between the airbag and the gas generator, the cover body can be easily manufactured without affecting the deployment of the airbag and the cover body.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 3, showing one embodiment of the steering wheel of the present invention.

FIG. 2 is an exploded perspective view of the airbag device.

FIG. 3 is a plan view of the steering wheel.

[Explanation of symbols]

 11 Steering wheel body 25 Airbag device 33 Gas generator 41 Horn switch mechanism 75 Airbag 81 Cover body

Claims (1)

(57) [Claims] 1. A steering wheel having a steering wheel body, an airbag device, and a horn switch mechanism for operating a horn mechanism in a pushed state, wherein the airbag device includes a gas generator and a gas generator. A steering comprising: an airbag housed on the occupant side of a generator; a cover body covering the airbag; and the horn switch mechanism provided between the gas generator and the airbag. wheel.