JPH10273007A - Air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the operability of a switching device installed in an air bag device. SOLUTION: An air bag 14 folded up is covered by a cover body 21 made of plastic. A switching device 18 provided with a membrane switch 16 and a back plate 17 is arranged between the cover body 21 and air bag 14. Cover body side projections 38d are radially projected from the back face of the cover body 21. Supporting side projections 44 are concentrically projected to the back plate 17. One point of the center section of the membrane switch 16 is fixed to the back plate 17. The back plate 17 is developed independently of the cover body 21 while the air bag 14 is being inflated with the extension section 17b of the back plate 17 mounted on a base plate 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, there is known an airbag device provided on a boss portion (center pad portion) of a steering wheel to protect a driver of an automobile from a collision impact or the like. The airbag device includes an inflator that injects gas, a bag-shaped airbag that is folded and stored, and a cover body (center pad) that covers the airbag.
And a base plate to which the inflator, airbag, cover body, and the like are attached. When the airbag device detects a collision of the vehicle,
Gas is injected from the inflator, the cover body is broken at a predetermined tear line (break line) by the pressure of the inflation of the airbag, and is developed into a door (door) shape, and the airbag is protruded from the cover body. It is designed to expand and deploy forward.

[0003] Conventionally, a switch for blowing a horn or the like is incorporated in a pad body arranged on the boss portion, and even in a vehicle equipped with an airbag device, an airbag device located in the boss portion is not used. By incorporating a switch in the cover body, operability is improved.

[0004] On the other hand, the door is formed on the cover so that the airbag can inflate and protrude. There is a need for a switch mechanism that can be turned on and off with a simple operation feeling.

In this regard, for example, an airbag device described in Japanese Patent Application Laid-Open No. 7-40838 is known. In this configuration, a film-like switch (membrane switch) is attached to the back surface of the cover body, and the back surface of the film-like switch is covered by a rigid panel (back panel). It is fixed. Then, when the cover body is pushed, the membrane switch is pushed through the cover body to close the circuit.

[0006]

However, in the configuration described in Japanese Patent Application Laid-Open No. 7-40838, a switch and a rigid panel are attached to a cover body that breaks and expands when the airbag is inflated and expanded, and the three-layer structure. In addition, the rigid panel is attached only to the cover body at a plurality of stopping points. Therefore, while it is necessary to firmly and reliably mount the switch and the rigid panel on the cover body, when the cover body is deployed, it is necessary to smoothly and quickly deploy the three-layer portion, which complicates the structure and increases the size. In addition, there is a problem that the manufacturing cost is increased due to an increase in the number of man-hours for mounting and difficulty in development. In addition, there is a problem that it is difficult to reduce the size of the airbag device as a whole due to securing the flexibility of the door piece of the cover body and increasing the volume occupied by the switch.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an airbag apparatus having a simple structure and a good switch operation feeling.

[0008]

According to a first aspect of the present invention, there is provided an airbag apparatus, comprising: an inflatable and deployable airbag; a cover body provided with a deformable and deployable covering portion for covering the airbag; A switch device disposed between the cover portion and the switch device, the switch device has a planar switch body, and a substantially central portion of the switch body is fixed,
A support portion supporting the airbag side of the switch body and having a support-side protrusion protruding toward the switch body and a deformable extension portion extending from the support portion are provided. And a support.

In this configuration, when the cover of the cover is pushed, the switch body of the switch device is pressed through the cover, and the switch is closed with at least a part of the switch body deformed. Is done. And
In the switch body, the airbag side is supported by the support portion of the support, and the protruding support-side ridge allows the pressing force to be concentrated on the portion that comes into contact with the support-side ridge, improving the operational feeling. I do. When gas flows into the airbag, the pressure of the airbag inflates and deploys, so that the covering portion breaks at a predetermined position and deploys, thereby forming a protrusion of the airbag. At this time, by fixing the extending portion to the portion other than the covering portion, the supporting portion to which the switch body is attached is developed independently of the covering portion, which affects the smooth deployment of the covering portion. Do not give. Further, although the switch body is attached to the support portion, the switch body has a substantially central portion fixed thereto, and thus does not affect the smooth deployment of the support portion. Furthermore, since the switch body is fixed to the support substantially at the center, the configuration and the manufacturing process are simplified, and the manufacturing cost is reduced.

According to a second aspect of the present invention, in the airbag apparatus of the first aspect, the cover body includes a cover body-side ridge protruding from the covering portion toward the switch body.

In this configuration, the cover body-side ridge protruding from the covering portion allows the force for pressing the covering portion to be concentrated on the portion in contact with the support-side ridge, thereby improving the operational feeling.

According to a third aspect of the present invention, there is provided the airbag apparatus according to the first or second aspect, wherein the switch body includes a pair of contact films, and a contact portion in which the contact films are opposed to and separated from each other. A non-contact portion where these contact films are not in contact with each other is provided, and at least one of the support-side ridge and the cover-side ridge is arranged to face the contact portion.

In this configuration, the non-contact portion provided for supporting the contact film or the like is avoided, and the contact film is opposed to the contact portion where the contact films are opposed to and separated from each other. By arranging at least one of the strips, the force for pressing the covering portion is efficiently used for contacting and separating the contact films, and the operational feeling is improved.

According to a fourth aspect of the present invention, in the airbag apparatus of the second or third aspect, the support-side ridge and the cover-side ridge are arranged to intersect each other.

In this configuration, the force for pressing the covering portion can be concentrated on the portion where the support side ridge and the cover body side ridge intersect with each other, so that the operational feeling is improved.

According to a fifth aspect of the present invention, there is provided an airbag apparatus according to any one of the second to fourth aspects, wherein one of the support side ridge and the cover side ridge is substantially concentric about a predetermined point. It is provided in a figure shape, and one of the other is radially arranged around the predetermined point.

In this configuration, the pressing force of the covering portion can be concentrated on a plurality of portions where the concentric projections and the radially arranged projections intersect each other, so that the operational feeling is improved.

According to a sixth aspect of the present invention, there is provided an airbag device, comprising: an airbag that is inflated and deployed; a cover body provided with a deformable and deployable covering portion that covers the airbag; and a cover body between the airbag and the covering portion. A contact portion provided with a pair of contact films, the contact films being opposed to and separated from each other,
A switch device having a planar switch body provided with a non-contact portion where these contact films do not contact each other,
The cover body includes a cover body-side ridge protruding from the covering portion so as to face the contact portion, and a protective rib protruding from the non-contact portion.

In this configuration, when the cover of the cover is pushed, the switch body of the switch device is pressed through the cover, and the switch is closed with at least a part of the switch body deformed. Is done. And
In the switch body, the pressing force is applied intensively to the contact portion by the cover body side ridge protruding from the covering portion, and the operational feeling is improved. Further, since the protective rib projecting from the covering portion contacts the non-contact portion, an excessive pressing force is suppressed from being applied to the contact portion, and the durability can be improved. Further, since the protective ribs need only be protruded from predetermined positions of the covering portion, the configuration and the manufacturing process are simplified, and the manufacturing cost is reduced.

According to a seventh aspect of the present invention, in the airbag device according to the sixth aspect, the protection rib is provided so as to protrude more toward the switch main body than the cover body side protrusion.

In this configuration, the protective rib abuts on the non-contact portion before the ridge comes into contact with the contact portion, so that the contact is unexpectedly closed when the covering portion is deformed. When the covering portion is pressed, the pressing force applied to the contact portion is suppressed,
Durability can be improved.

According to an eighth aspect of the present invention, in the airbag apparatus according to the sixth aspect, the protective rib is provided so as to protrude toward the switch body side smaller than the cover body side ridge.

In this configuration, when the covering portion is pressed, when a load is further applied after the ridge comes into contact with the contact portion, the protective rib comes into contact with the non-contact portion, so that the contact portion can be moved to the contact portion. Applying an excessive pressing force is suppressed, and the durability can be improved.

[0024]

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

In FIG. 2, reference numeral 1 denotes a steering wheel of an automobile. The steering wheel 1 includes a steering wheel body 2, an airbag device (airbag module) 4 mounted on the occupant side of the steering wheel body 2, and the like. It is composed of The steering wheel 1 is mounted on a steering shaft which is normally provided in an inclined state. Hereinafter, a vehicle body on which the occupant side which is the front side of the airbag device 4 is the upper side and the vehicle body which is the bottom side of the airbag device 4 will be described below. In the following description, the side will be referred to as the lower side, the upper front side of the vehicle, ie, the windshield side as the front side, and the lower rear side of the vehicle, ie, the front side of the occupant as the rear side.

The steering wheel body 2 is
The rim 5 has an annular shape, a boss 6 located inside the rim 5, and four spokes 7 connecting the rim 5 and the boss 6. A cylindrical boss fitted to a steering shaft (not shown) is provided below the boss 6 on the vehicle body side, and a boss plate is integrally attached to the boss by welding or the like. I have. Then, the core metal of the spoke portion 7 is connected to the boss plate, and the spoke portion 7
Is connected to the core metal of the rim portion 5. further,
A skin portion 8 made of a soft foamed polyurethane resin or the like is formed on an outer peripheral portion of the core metal of the rim portion 5 and an outer peripheral portion of a portion of the spoke portion 7 on the rim portion 5 side of the core metal.

The airbag device 4 is mounted above the boss 6, and as shown in FIGS. 1 to 3, an inflator 12 and an airbag 14 are mounted on a base plate 11 as a mounting member. Base plate 11
And a switch device 18 including a retainer 15, a membrane switch 16 as a switch main body and a back plate 17 as a support, and a cover body 21.

The base plate 11 is formed by bending a steel plate to form an upper plate portion 11a having a substantially rectangular planar shape.
A substantially rectangular cylindrical peripheral wall portion 11b that extends downward from the peripheral portion of 11a
Are formed. In addition, a circular hole-shaped inflator mounting hole 11c is formed in the center of the upper plate portion 11a, and a plurality of bolt through holes 11d are formed around the inflator mounting hole 11c. ing. Further, a pair of bracket mounting portions 11f on both sides is provided on the peripheral wall portion 11b.
A nut is integrally mounted inside the bracket mounting portion 11f, and a plurality of rivet through holes 11h are formed in the peripheral wall portion 11b at predetermined intervals. Further, the front and rear peripheral wall portions 11b are provided with rivet through holes 11h.
A locking hole 11i is formed between the two. The base plate 11 is provided with a bracket mounting portion 11f.
The steering wheel body 2 is fixed to a pair of brackets on both sides provided on a boss plate of the steering wheel body 2 by bolts screwed to the nuts. Further, outwardly directed stoppers 11j are integrally formed at a plurality of locations at the lower end of the peripheral wall portion 11b.

The inflator 12 has a substantially cylindrical inflator body 12a, and gas injection ports 12b for injecting gas are formed radially at predetermined intervals on an upper portion of the inflator body 12a. From the inflator body 12a, a flange portion 12 for attachment toward the outer peripheral side is formed.
and a plurality of bolt holes 12d are formed in the flange portion 12c. In addition, the inflator body 12
a is provided with a starting portion (igniter, squib) connected to a lead wire 12e led out from the lower side of the inflator body 12a, and a medicine is provided so as to surround the starting portion. The pellets are filled, and by applying electric energy to the starting portion, the reaction of the drug pellets is started, and a large amount of inert gas, for example, nitrogen gas, is instantaneously generated and ejected from the gas injection port 12b. ing.

On the other hand, the airbag 14 is formed in a bag shape by, for example, stacking two circular base cloths of the same outer shape made of a woven cloth or the like and sewing the outer periphery thereof. Also airbag
A circular opening 14c into which the upper half of the inflator 12 is inserted is provided in the center of the lower surface of the inflator 12, and a plurality of bolt holes 14d are formed around the opening 14c. At the same time, a deaeration port (not shown) is formed at a position separated from the opening 14c. Further, in the vicinity of the opening 14c and the deaeration port, annular reinforcing cloths are respectively stacked and sewn together to be reinforced.

The retainer 15 includes an annular base portion 15a and a bulge portion 15b called a cup portion extending upward from an inner peripheral edge of the base portion 15a. Are formed in combination. The base portion 15a has a planar outer shape of a rectangular shape with rounded corners, a circular inside opening, and a plurality of through holes (not shown) formed in the planar portion of the base portion 15a. At regular intervals, mounting bolts 24 are inserted into these through holes from above, respectively, and are integrally fixed by spot welding or the like. A nut (not shown) is screwed into each mounting bolt 24 from the tip. On the other hand, the bulging portion 15b has a cylindrical portion 15c extending upward from the base portion 15a, and a frusto-conical portion 15d extending above the cylindrical portion 15c and having a diameter smaller upward. And an upper plate portion 15e for closing the upper surface of the frusto-conical portion 15d. The upper half of the inflator body 12a of the inflator 12 is housed mainly inside the cylindrical portion 15c of the bulging portion 15b, and the truncated conical portion 15 is separated from the cylindrical portion 15c.
A plurality of gas insertion ports 15f are formed over d.

As shown in FIGS. 1 to 6, the cover body 21 is integrally formed by injection molding of a synthetic resin material such as a soft thermoplastic elastomer, for example, an olefin-based elastomer. Body 2
Cover 31 covering a part of boss 6 and spoke 7
And a substantially square tubular mounting piece 32 protruding downward from the back surface of the covering portion 31.

The surface (upper surface) of the cover portion 31 of the cover body 21 is formed by combining the curved surface curved in the front-rear direction and both side directions in harmony with the skin portion 8 covering the four spoke portions 7. It is designed to be in harmony with the instrument panel. Further, the back surface (lower surface) of the covering portion 31 of the cover body 21 is located inside the mounting piece portion 32 and is recessed in a substantially H-shaped plane, and is more fragile than other portions of the covering portion 31. A tear line 36 is formed as a break portion (planned break portion). In other words, this tear line 36
Is a cross section 36a extending longitudinally on both sides and this cross section
A pair of longitudinal sections 36b are provided at both ends of the mounting section 32a and extend along the inside of the mounting piece 32.When the airbag 14 is inflated, the covering section 31 is torn along the tear line 36,
A pair of front and rear door pieces 37a and 37b that rotate and deploy forward and backward are formed. In addition, this tear line 36
The crossing portion 36a is deviated to the rear (toward the occupant) from the center of the covering portion 31, and is formed to be linear or curved toward the front. In addition, the terminal section 36c of each longitudinal section 36b
Is inverted so that the tip is parallel to the longitudinal section 36b,
When the door pieces 37a and 37b are formed, the propagation of the break to portions other than the tear line 36 is prevented.

Further, on the back side of the front door piece portion 37a,
A switch arrangement part 38 is formed. The switch disposing portion 38 has a thin portion 38a that is recessed in a substantially elliptical shape.
Are formed, and a horn switch operating portion that can be elastically deformed in the vertical direction is formed. Except for the front end of the thin portion 38a, a thick portion 38b having a substantially flat lower surface is formed so as to surround substantially the entire periphery of the thin portion 38a. Furthermore, this thin part
From 38a, a plurality of cover body side ridges 38d
Are protruding radially. Each of the cover body-side protrusions 38d is formed so as to be centered on a point substantially at the center of the switch disposing portion 38 and independently of each other except for the vicinity of the center. Further, a plurality of bosses 38e project from the thick portion 38b toward the lower side.

On the other hand, the mounting piece 32 of the cover body 21 has a substantially rectangular cylindrical shape fitted to the outside of the peripheral wall 11b of the base plate 11, and the rivet through hole 32a communicating with the rivet through hole 11h of the peripheral wall 11b. Are formed at predetermined intervals. Also,
The mounting piece 32 has a pair of cutouts for mounting portions, which are located on both sides and are fitted to the bracket mounting portions 11f on both sides, and are located between the front and rear rivet through holes 32a. A locking projection 32c is provided. As shown in FIG. 4, a pair of projections 32d on both sides are formed on the inner surface of the mounting piece 32, as shown in FIG.

The back plate 17 of the switch device 18
As shown in FIG. 1 to FIG. 3 and FIG. 7, a switch holding portion 17a as a support portion having a substantially elliptical planar shape and having a predetermined rigidity, and an extension extending from the switch holding portion 17a. The portion 17b is integrally formed of a synthetic resin such as a polyester elastomer by injection molding or the like. Then, at the approximate center of the switch holding portion 17a,
The locking portion 41 constituting the fixing means is integrally formed.
The locking portion 41 has a substantially T-shape, and is formed in a columnar shape from the center of the switch holding portion 17a and protruding upward from the center thereof. Part 17a
Is formed integrally with a locking piece 43 protruding in both sides along the line. Note that a slit 43a is formed in the switch holding portion 17a, which is located below the locking piece portion 43, so that the switch holding portion 17a can be formed by a mold having a simple structure which can be vertically separated and moved. When a mold having a slide mechanism that moves in the direction is used, the slit 43a is not always necessary. Further, on the upper surface of the switch holding portion 17a,
A plurality of support-side ridges (circular ribs) 44 are formed in a concentric shape having a concentric diagram centering on the shaft portion 42, and these support-side ridges 44 are connected to each other. A connecting ridge 45 is provided radially around the portion 42. The connecting protrusion 45 has a smaller projecting dimension than the support-side protrusion 44. At the distal end of the extension 17b of the back plate 17, there is formed a mounting portion 17c protruding toward both sides, and the mounting portion 17c is mounted at a predetermined interval in both sides. A hole 17d is formed. Further, the switch holding portion 17a is provided with an annular rib so as to surround the support side ridge 44 and the connection ridge 45.
17e is protruding. And this annular rib 17e is
A plurality of positioning bosses 17f protrude from the upper surface of the annular rib 17e, and a plurality of guides are further provided on the outer peripheral side of the annular rib 17e. A hole 17g is formed. Further, a pair of harness guide ribs 17h on both sides are formed on the surface side of the corner between the switch holding portion 17a and the extension portion 17b.

On the other hand, the membrane switch 16 constitutes a horn switch of an automobile, and as shown in FIGS. 1, 3 and 8 to 10, an elastically deformable or flexible planar ellipse. The switch body 16a has a planar shape, that is, a (thin) film shape, a sheet shape, and a planar shape. The switch body 16a is
Similar to 17a, the whole is mounted on the switch holding portion 17a. The switch body 16a is
Sheets 47 and 47 made of a film body (polyester film) or a polyethylene terephthalate (PET) resin formed from a pair of polyester resins or the like superposed on each other are provided. Alternatively, a conductive film made of a copper foil or the like having a predetermined pattern, that is, a contact film 48 serving as an electrode,
48 are formed by sticking or printing. Further, between these contact films 48, spacers 50 and dot spacers 51 having insulating properties and being compressively deformable are arranged at predetermined positions. The spacer 50 has an outer peripheral portion 50a that forms a substantially annular shape along the outer periphery of the sheet 47, and a substantially cross-shaped crossover portion that connects the central portion and the outer peripheral portion 50a with a constant width through the center of the sheet 47. And 50b are integrally formed. The dot spacers 51 are made of silicon rubber or the like, and are formed on the surface of one contact film 48 by screen printing or the like at regular intervals in dots on a circle and an ellipse concentric with each other. The portion where the spacers 50 and the dot spacers 51 are arranged becomes a non-contact portion 54 where the contact films 48 are not directly contacted and separated from each other, and the portion where the spacers 50 and the dot spacers 51 are not arranged is a contact film. 48 constitute a contact portion 55 which is directly opposed to and separated from each other. When no force is applied to the switch body 16a, that is, when the switch body 16a is maintained in a substantially planar shape, the contact films 48 are separated from each other and the switch is opened, and the switch body 16a is pressed by pressing the switch body 16a. The contact films 48 of the contact portion 55 come into contact with each other in a state where at least a part of the switch is curved, and the switch (circuit) is closed.

Each contact film 48 has a terminal 48
The harness (lead wire) 57 is connected to each of these terminal portions 48a one by one, and a so-called piercing compression terminal 58 is connected to the tip of each harness 57. Each contact film 48 is connected to a horn circuit on the vehicle body via the harness 57 and a cable reel device (not shown).

Further, a lock receiving portion 61 is formed at the center of the switch body 16a of the membrane switch 16. The locking receiving portion 61 is formed in a bearing hole portion having a circular hole shape.
61a and an insertion hole 61b continuous before and after the bearing hole 61a.
Are similar to the shaft portion 42 and the locking piece 43 of the locking portion 41, respectively, and are formed in a state rotated by 90 degrees. A plurality of positioning holes 16b are formed in the vicinity of the outer peripheral edge of the switch body 16a.

Next, the assembly process of the airbag device 4 will be described.

First, the membrane switch 16 is attached to the back plate 17 to constitute the switch device 18. At this time, as shown in FIG. 11, the membrane switch 16 is rotated, and the bearing hole portion of the locking receiving portion 61 of the membrane switch 16 is rotated.
61a and the insertion hole 61b
41 and are inserted in alignment with the shaft part 42 and the locking piece part 43. First, in this state, the shaft 42 is rotatably positioned and held in the bearing hole 61a. Subsequently, the membrane switch 16 is turned about 90 degrees to be directed in a predetermined direction. In this state, as shown in FIG. 12 and FIG.
Is fixed to the upper surface of the membrane switch 16, and the membrane switch 16 is fixed to the back plate 17 at one point in the center. Further, in this state, the positioning boss 17f of the back plate 17 is inserted into the positioning hole 16b of the membrane switch 16, and the harness guide rib 17h of the back plate 17 guides the terminal portion 48a and the harness 57 of the membrane switch 16, and the membrane The relative rotation between the switch 16 and the back plate 17 is prevented and positioning is performed. In addition to these structures, the reinforcing film 63 shown in FIG.
Is adhered on the membrane switch 16 so as to surround the locking piece 43 in the locked state, so that the rotation can be more firmly stopped. Also, by previously attaching the reinforcing film 63 to the upper surface or upper and lower surfaces of the membrane switch 16 along with the lock receiving portion 61, by locking the locking piece 43,
As a reinforcing member for reinforcing the locking receiving portion 61, the membrane switch 16 can be firmly and reliably held even when the airbag 14 is deployed. The reinforcing film 63 may be formed of a thin metal piece or the like in addition to the resin.

In this state, as shown in FIG.
The annular support-side ridge 44 of the back plate 17 is formed so as to be aligned with the contact portion 55 of the membrane switch 16. That is, the dot spacers 51 of the membrane switch 16 are arranged concentrically, avoiding the support-side protrusions 44.

Next, the airbag 14 is connected to the base plate 11.
To attach the airbag to the airbag, insert the retainer 15 through the opening c into the inside of the airbag.
Insert the mounting bolts 24 into d. Then, the opening 14c of the airbag 14 and the inner peripheral edge of the base 15a of the retainer 15 are aligned. Subsequently, the mounting bolts 24 protruding from the airbag 14 are attached to the base plate 11 from above.
When inserted into the bolt through hole 11d, the inflator mounting hole 11c of the base plate 11 is aligned with the opening 14c of the airbag 14. Therefore, in this state, the airbag 14 is sandwiched and temporarily fixed between the retainer 15 and the base plate 11.

Subsequently, for example, the airbag 14 is
The airbag 14 is folded so as to fit in the outer peripheral shape of the upper plate portion 11a of the base plate 11 so as to be wound in a petal shape around the outer peripheral portion of the 15 bulging portion 15b. At this time, the airbag
14 is such that only one base cloth is located on the upper plate portion 15e of the bulging portion 15b, and the other portions are folded around the bulging portion 15b.

The extension 17 of the membrane switch 16
b is engaged with the projection 32d of the cover body 21, and the boss 38e is inserted into the guide hole 17g for positioning, and the switch device 18 having the membrane switch 16 mounted on the back plate 17 is moved to the cover body 21. At a predetermined position inside the. Further, from this state, the peripheral wall portion 11b of the base plate 11 to which the folded airbag 14 is attached is attached to the cover body.
The airbag 14 is fitted into the inside of the mounting piece 32 of the 21, and the airbag 14 is covered with the cover 21.

The locking projection 32c projecting from the mounting piece 32 of the cover body 21 is engaged with the locking hole 11i of the peripheral wall 11b of the base plate 11 to perform positioning and temporary fixing. In this state, the rivet R shown in FIG. 1 is inserted into the rivet through hole 32a from the outside of the mounting piece 32 of the cover body 21, and at least one rivet R is inserted into the center locking hole 17d of the back plate 17. Through the peripheral wall 11 of the base plate 11
b is inserted through the rivet through hole 11h, and each rivet R is swaged, so that the cover 21 is inserted into the base plate 11.
Is fixed.

In this state, the membrane switch 16
Of the switch body 16a of the cover body 21
And the membrane switch 16 is supported by the back plate 17 and the retainer 15 having predetermined rigidity, and the mounting portion 17c of the back plate 17 is located between the upper plate portion 15e and the airbag 14 on the retainer 15. Is fixed between the peripheral wall portion 11b of the base plate 11 and the mounting wall portion 32 of the cover body 21. That is, in this state, the switch body 16a of the membrane switch 16 is disposed between the cover-side protrusions 38d of the cover body 21 and the support-side protrusions 44 of the back plate 17 that are orthogonal to each other.

Further, in this state, the locking portion 41 of the back plate 17 is disposed at the central portion of the cover 21 where the cover-side protruding ridge 38d is not formed.

In this state, the thick portion of the cover 21 is
38b is in contact with the outer peripheral portion of the back plate 17, and the lower surface, that is, the tip portion of the cover-side protruding ridge 38d of the cover body 21 is spaced apart from the operation surface of the membrane switch 16 attached to the back plate 17 by a predetermined distance. , And are set to be parallel.

Subsequently, from the back side of the base plate 11,
The inflator body 12a of the inflator 12 is inserted into the opening 14c of the airbag 14 via the inflator mounting hole 11c, and is disposed in the bulging portion 15b, and the base plate
The airbag device 4 is assembled as shown in FIG. 3 by inserting the mounting bolts 24 projecting downward from the bottom 11 into the bolt holes 12d of the flange portion 12c and tightening and fixing them with nuts.

In the airbag device 4, the bracket mounting portion 11 f of the base plate 11 is fixed to the bracket of the steering wheel body 2 with bolts to be fixed to the steering wheel body 2, and the harness of the membrane switch 16 is fixed. By connecting 57 to a cable reel device or a slip ring device, the membrane switch 16 is connected to a circuit of a horn device provided on the vehicle body side.

When the horn switch operating portion of the covering portion 31 of the cover body 21 is pressed (pushed) with a finger or the like, the horn switch operating portion is bent downward and elastically deformed. Then, the cover body-side ridge 38d provided on the back surface of the horn switch operation unit presses the upper surface of the membrane switch 16 whose lower surface is supported by the back plate 17, thereby deforming the membrane switch 16 to compress the thickness dimension. The membrane switch 16 is sandwiched between the radial cover body side ridge 38d of the body 21 and the concentric support body side ridge 44 of the back plate 17, and the circuit is closed with the opposing contact films 48 in contact with each other. ,
The horn sounds.

When a vehicle collides, a signal from a collision diagnosis unit (not shown) is used to inflate the vehicle.
By activating the igniter 12 and reacting the charged propellant, the airbag 14 is opened via the gas injection port 12b formed on the peripheral surface of the inflator 12 and the gas insertion port 15f formed on the retainer 15. An inert gas such as a nitrogen gas is rapidly injected into the inside, and the folded airbag 14 is rapidly inflated. Then, due to the pressure of the inflation of the airbag 14, the covering portion 31 of the cover body 21 is cut along the tear line 36 in a substantially H shape, and a pair of front and rear door pieces is formed. Further, these door pieces rotate back and forth, and the back plate 17 to which the membrane switch 16 is attached rotates forward to form a projecting opening of the airbag 14, from which the airbag 14 projects. Thus, it inflates and deploys to the front of the occupant to reduce the impact of the collision.

According to the present embodiment, the horn switch operating portion of the covering portion 31 of the cover body 21 located on the boss portion 6 of the steering wheel 1 is pushed, so that the membrane switch is switched via the covering portion 31. Since the horn can be blown by pressing the horn 16, the operability of the horn switch can be improved.

The switch body 16a of the membrane switch 16 is supported by a back plate 17 and a retainer 15 having a predetermined rigidity, and has a cover body.
The cover body side ridge 38d of 21 is made radial and the back plate
Since the 17 support-side ridges 44 are concentric, the area of the portion to which the pressing force is applied is reduced, that is, the pressing force is concentrated at the intersection of the cover body-side ridges 38d and the support-side ridges 44, The switch body 16a is efficiently deformed, the operation load is reduced, the responsiveness is improved, and the operational feeling can be improved.

Further, the annular support-side ridge 44 of the back plate 17 is formed so as to be aligned with the contact portion 55 of the membrane switch 16.
Since the dot spacers 51 are arranged concentrically avoiding the support side protrusions 44, the contact films opposing each other at the contact portion 55
48 can be reliably contacted with each other to improve the horn operation feeling.

Further, since the lower surface of the cover-side ridge 38d of the cover body 21 is parallel to the operation surface of the membrane switch 16 attached to the back plate 17, the operating force at each position on the cover body 21 is made uniform. , Operation feeling can be improved.

Further, since the horn switch operating portion of the covering portion 31 of the cover body 21 is the thin portion 38a, the operating load can be reduced and the operational feeling can be improved.

Further, the cover body 21 has a thick portion 38d which is thicker than the general portion on substantially the entire outer periphery of the thin portion 38a, and this thick portion 38d is used as the switch holding portion 17a of the back plate 17. Abuts the outer periphery of the airbag 14
The thin portion 38a can be protected and smoothly broken along the tear line 36 during the deployment.

The operation feeling can be more easily improved by setting the hardness of the back plate 17 to be equal to or higher than the hardness of the covering portion 31 of the cover body 21. Further, the bulging portion 15 is formed on the retainer 15.
Since b is provided and the lower side of the back plate 17 is supported via one base cloth, when the horn operating part of the covering part 31 is pushed, an appropriate response is generated, and the operational feeling can be improved.

The switch device 18 is a switch holding portion of the back plate 17 to which the membrane switch 16 is attached.
The extension portion 17b extending from the base member 17a is attached to and supported by the base plate 11, and the cover portion 31 of the cover body 21 is positioned only and not fixed. When forming 14 protrusions,
The back plate 17 includes a switch holding portion 17a and an extension portion.
17b is unfolded independently of the cover body 21 while being deformed, and does not affect the unfolding of the door piece of the cover body 21. In addition, since the membrane switch 16 is fixed to the back plate 17 at one point, the back plate 17 itself is freely deformed and expanded without being affected by the membrane switch 16, and a plurality of fixing points are provided. No force such as pulling and pressing is generated. In this way, the door piece of the cover body 21 and the switch device 18 can be smoothly deployed, and the airbag 14 can be quickly and smoothly inflated and deployed.

The membrane switch 16 is fixed to the back plate 17 at one point (one point).
Since the 41 can be easily fixed by a simple operation of inserting and rotating into the lock receiving portion 61, the manufacturing process can be simplified, the number of steps can be reduced, and the manufacturing cost can be reduced. Further, the shaft portion of the locking portion 41
The engaging operation can be facilitated by holding the shaft 42 in a rotatable manner by the bearing hole 61a of the locking receiving portion 61, and the shaft 42 is held by the bearing hole 61a and the side of the insertion hole 61b. By preventing the movement of the membrane switch 16, the membrane switch 16 can be accurately positioned and held.

Further, since the locking portion 41 is formed integrally with the back plate 17, the number of components is not increased, the structure is simplified, and the manufacturing cost can be reduced.

Further, since the central portion of the membrane switch 16 is fixed to the back plate 17, it can be stably held even if it is fixed at one point.

The spacer 50 of the membrane switch 16
By integrally forming the annular outer peripheral portion 50a and the cross-shaped crossover portion 50b, the manufacturing cost can be reduced. The crossover portion 50b from the central portion to the outer peripheral portion may be formed at four places to form a cross shape, or may be formed at one to three places or at five or more places.

In the above-described embodiment, the covering rib 31 is provided by projecting a protection rib from the cover body 21 so as to face the spacer 50 or the dot spacer 51 which is the non-contact portion 54 of the membrane switch 16. By pressing the protective rib against the non-contact portion 54 when pressing, for example, excessive pressing force is applied to the contact portion 55, and the durability of the switch device 18 can be improved. The protective rib can make the height dimension and the width dimension equal to the ridge pressing the contact portion 55. It can be different.

For example, as shown in FIGS. 14 to 16, the non-contact portion 54 of the membrane switch 16 is a spacer.
A protection rib 71 projecting more toward the membrane switch 16 than the other cover body side ridges 38d can be formed along the transition portion 50b of the 50.

In this configuration, the protective rib 71 comes into contact with the non-contact portion 54 before the cover-side protruding ridge 38d comes into contact with the contact portion 55 of the membrane switch 16, so that the resin covering portion 31 is formed. Temperature changes, for example, when shrinking and deforming due to low temperature, etc., can prevent the cover body side ridge 38d from abutting and unexpectedly closing the contact, and when the covering portion 31 is pressed, the protective rib 71 By dispersing the force by contact with the non-contact portion 54, it is possible to suppress an impressive pressing force or the like from being applied to the contact portion 55, thereby improving the durability of the switch device 18.

As shown in FIGS. 17 to 19,
A protection rib 73 projecting along the crossover portion 50b of the spacer 50, which is the non-contact portion 54 of the membrane switch 16, on the membrane switch 16 side smaller than the other cover body side ridge 38d.
Can be formed.

In this configuration, when the cover portion 31 is pressed and the cover body side ridge 38d abuts on the contact portion 55 and is closed, and when a load more than necessary is applied, that is, the horn operation is performed. If an abnormal impact greater than the force
The contact of the 73 with the non-contact portion 54 disperses the force, so that the durability of the switch device 18 can be improved.

Further, in each of the above embodiments, the membrane switch 16 of the switch device 18 has a flat elliptical shape, but may have various shapes such as a circular shape and a rectangular shape. Further, the switch device 18 can also be configured by arranging a plurality of membrane switches 16 side by side on the upper surface of the switch holding portion 17a of the back plate 17, and fixing the central portion to the back plate 17 at one point.

Then, the cover 21 and the back plate
The ridges formed on the base plate 17 can also take various shapes. For example, the ridges on the back plate 17 may be only the concentric support-side ridges 44 and the connecting ridges 45 may not be formed. Alternatively, the cover body 21 and the back plate
Each of the 17 ridges has a plurality of parallel lines, and is formed at an angle of intersection such as orthogonal to each other, and is vertically intersected. 16a can be efficiently deformed to reduce the operation load and improve the responsiveness, thereby improving the operational feeling.

Further, the cross-sectional shape of these ridges can also take various shapes. For example, by pressing the tip of the ridge, the pressing force can be partially concentrated,
The switch body 16a can be efficiently deformed to improve the operational feeling.

The locking portion 41 and the locking receiving portion 61 can also take various shapes to engage with each other.

Further, in the above embodiment, the locking piece 43 of the locking portion 41 of the back plate 17 has a longitudinal direction along both sides, that is, a direction intersecting the developing direction.
Although the configuration was designed to suppress the influence of the unfolding, this locking piece 43
Can be projected in the front-rear direction, that is, along the direction in which the switch holding portion 17a of the back plate 17 is deployed. By protruding the locking pieces 43 along the deployment direction in this manner, the membrane switch 16 can be easily and reliably held even when the back plate 17 is deployed.

In each of the above embodiments, the membrane switch 16 is attached to the back plate 17 by locking. Alternatively, the membrane switch may be caulked using a rivet or the like, and may be heat-sealed or bonded. The switch 16 can be attached to the back plate 17.

In the above embodiment, the switch device 18 is connected to the membrane switch 16 and the back plate 17.
However, the operation feeling can be easily improved by laminating the elastically deformable cushion members on these members to form a three-layer structure. This cushion member is disposed on the top, that is, on the cover 21 side of the membrane switch 16, and the membrane switch 16 and the back plate 17
Or the lowermost layer, that is, on the airbag 14 side of the back plate 17.

In each of the above embodiments,
Although the airbag device 4 provided in the steering wheel 1 has been described, the present invention can also be applied to an airbag device provided in an instrument panel, a seat, or the like when a switch is provided.

[0079]

According to the first aspect of the present invention, the cover body of the cover body is pushed to push the switch body of the switch device through the cover part, and at least one of the switch body is pushed. The switch can be closed with the part deformed. The switch body has the airbag side supported by the support portion of the support, and the protruding support-side ridge allows the pressing force to be concentrated on the portion that comes into contact with the support-side ridge. Can be easily improved. In addition, when gas flows into the airbag, the pressure of the airbag inflates and deploys, so that the covering portion breaks at a predetermined position and deploys to form a protruding port of the airbag. Can be expanded. At this time, by fixing the extended portion to the portion other than the covering portion, the supporting portion to which the switch body is attached is developed independently of the covering portion, and the covering portion can be smoothly developed. it can. The switch body is attached to the support portion, but the switch body is fixed substantially at the center, so that the support portion can be smoothly deployed.
Furthermore, since the switch body is fixed to the support substantially at the center, the configuration and the manufacturing process can be simplified, and the manufacturing cost can be reduced.

According to the airbag device of the second aspect,
In addition to the effect of the first aspect, the cover body-side ridge protruding from the covering portion allows the force for pressing the covering portion to be concentrated on the portion in contact with the support-side ridge, thereby improving the operational feeling.

According to the airbag device of the third aspect,
3. In addition to the effects of claim 1 or 2, the support member side ridge and the cover are opposed to the contact portion where the contact films are opposed to and separated from each other while avoiding a non-contact portion provided for supporting the contact film. By arranging at least one of the body-side ridges, the force pressing the covering portion can be efficiently used for contacting and separating the contact films, and the operational feeling can be improved.

According to the airbag device of the fourth aspect,
In addition to the effects described in claim 2 or 3, by disposing the support side ridge and the cover body side ridge to intersect each other,
Since the force for pressing the covering portion can be concentrated on the intersecting portion, the operational feeling can be improved.

According to the airbag device of the fifth aspect,
5. In addition to the effects of any one of claims 2 to 4, one of the support side ridge and the cover body side ridge is provided in a substantially concentric shape centered on a predetermined point, and the other is centered on the predetermined point. By radially arranging, since the concentric projections and the radially arranged ridges can concentrate the pressing force on the covering portion at a plurality of intersections with each other,
Operation feeling can be improved.

According to the airbag device of the sixth aspect,
By pushing the cover portion of the cover body, the switch body of the switch device is pressed through the cover portion, and the switch can be closed with at least a part of the switch body deformed. In the switch body, the pressing force is concentrated on the contact portion by the cover body-side ridge protruding from the covering portion, and the operational feeling can be improved. Further, by contacting the protection rib protruding from the covering portion with the non-contact portion, an excessive pressing force on the contact portion can be suppressed, and the durability of the switch device can be improved. Further, since the protective ribs need only be protruded from predetermined positions of the covering portion, the configuration and the manufacturing process can be simplified, and the manufacturing cost can be reduced.

According to the airbag device of the seventh aspect,
In addition to the effect of claim 6, by providing the protection rib so as to protrude more toward the switch body than the cover body side protrusion,
Because the protective rib contacts the non-contact portion before the ridge contacts the contact portion, it is possible to prevent the contact from being accidentally closed when the coating is deformed, and to press the coating. In such a case, it is possible to suppress an impressive pressing force or the like from being applied to the contact portion, thereby improving the durability of the switch device.

According to the airbag device of the eighth aspect,
In addition to the effect of claim 6, by providing the protection rib projecting to the switch body side smaller than the cover body side ridge,
When a load is applied after the ridge comes into contact with the contact part when pressing the covering part, the protective rib comes into contact with the non-contact part, so it is possible to suppress the application of excessive pressing force to the contact part. ,
The durability of the switch device can be improved.

[Brief description of the drawings]

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

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

FIG. 3 is a sectional view of the airbag device, taken along the line II of FIG. 2;

FIG. 4 is a bottom view of a cover body of the airbag device.

FIG. 5 is a sectional view of a cover body of the airbag device.

FIG. 6 is an enlarged sectional view of a part of a cover body of the airbag device.

FIG. 7 is a perspective view of a support of the airbag device.

FIG. 8 is a perspective view of a switch body of the airbag device.

9 is a cross-sectional view of the airbag device of FIG.

FIG. 10 is an explanatory diagram of a switch body of the airbag device.

FIG. 11 is an explanatory diagram of an assembling process of the switch device of the airbag device.

FIG. 12 is an explanatory view of a part of the switch device of the airbag device.

FIG. 13 is a cross-sectional view of a part of the switch device of the airbag device.

FIG. 14 is a cross-sectional view showing another embodiment of the airbag device of the present invention.

FIG. 15 is a cross-sectional view of a part of the airbag device.

FIG. 16 is a cross-sectional view of a part of the airbag device.

FIG. 17 is a cross-sectional view showing another embodiment of the airbag device of the present invention.

FIG. 18 is a cross-sectional view of a part of the airbag device.

FIG. 19 is a cross-sectional view of a part of the airbag device.

[Explanation of symbols]

 4 Airbag device 14 Airbag 16 Membrane switch as switch body 17 Back plate as support 17a Switch holding portion as support 17b Extension 18 Switch device 21 Cover body 31 Covering part 38d Cover body side ridge 44 Support side Protrusion 48 Contact film 54 Non-contact part 55 Contact part 71 Protective rib 73 Protective rib

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuyoshi Nishijima 218 Aoshima-cho, Fuji-shi, Shizuoka Pref.

Claims (8)

[Claims] An airbag that inflates and deploys, a cover body provided with a deformable and deployable covering portion that covers the airbag, and a switch device disposed between the airbag and the covering portion. The switch device comprises: a planar switch body; and a substantially central portion of the switch body, the support body supporting the airbag side of the switch body and projecting toward the switch body. An airbag device comprising: a support portion provided with a ridge; and a support member provided with a deformable extension portion extending from the support portion. 2. The airbag device according to claim 1, wherein the cover body includes a cover body-side ridge protruding from the covering portion toward the switch body. 3. The switch body includes a pair of contact films,
A contact portion in which the contact films are opposed to and separated from each other, and a non-contact portion in which the contact films are not in contact with each other are provided, and at least one of the support-side protrusion and the cover-side protrusion is opposed to the contact portion. The airbag device according to claim 1, wherein the airbag device is disposed. 4. The airbag device according to claim 2, wherein the support-side ridge and the cover-body-side ridge are arranged to cross each other. 5. One of the support-side ridge and the cover-side ridge is provided in a substantially concentric shape with a predetermined point as a center, and the other is radially arranged with the predetermined point as a center. The airbag device according to any one of claims 2 to 4, wherein: 6. An airbag that inflates and deploys, a cover body provided with a deformable and deployable covering portion that covers the airbag, and a pair of contact films disposed between the airbag and the covering portion. A switch device having a planar switch body provided with a contact portion in which these contact films are opposed to and separated from each other, and a non-contact portion in which these contact films do not contact each other; An airbag device comprising: a cover-side ridge protruding from a covering portion to face a contact portion; and a protective rib protruding from a non-contact portion. 7. The airbag device according to claim 6, wherein the protection rib is provided so as to protrude more toward the switch body than the protrusion on the cover body side. 8. The airbag device according to claim 6, wherein the protection rib is provided so as to project toward the switch main body side smaller than the cover body side protrusion.