JPH08216817A - Module cover for air bag device - Google Patents

Abstract

PURPOSE: To certainly actuate a horn switch built in an air bag module cover. CONSTITUTION: A plate type flap 16 is integrally molded of resin with a module cover main body on a module cover inner surface 18. The plate type flap 16 and a membrane-switch 20 are fixed and supported at a specified position of the module cover inner surface 18 by a heat stick 30 formed on the module cover inner surface 18 by bending the plate type flap 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a module cover for an airbag device, and more particularly to a module cover for an airbag device in which a membrane switch as a horn switch is mounted on a steering pad portion to ensure reliable operation.

[0002]

2. Description of the Related Art An air bag module which constitutes a conventional air bag device for a driver's seat is entirely housed in a space formed by a module cover which serves as a steering pad. Then, when the automobile collides, the inflator is actuated by the impact applied to the sensor, and the reaction gas ejected from the inflator causes the airbag body to inflate and deploy into a predetermined bag shape. At this time, the airbag is housed in the module cover in a folded state. Then, a part of the module cover is cleaved by the inflation pressure of the airbag, and a part of the airbag is inflated so as to jump toward the driver in the vehicle compartment. In this way, it is possible to prevent a secondary collision in which the driver, who has moved forward due to the impact of a collision, collides with the airbag deployed in front of the driver and collides with the steering wheel or the like.

FIG. 11 is a front view of a steering wheel 50 in which an air bag module is housed in a module cover 51 which is a steering pad in appearance. As shown in the figure, the steering wheel 50 is connected to the steering pad by four spokes 52. In many cases, in this type of steering wheel 50, a horn switch composed of two to four small press buttons 53 is provided at the root of the spoke portion as shown in the figure. This horn switch is configured by operatively fitting a small rectangular resin press button 53 in a recess formed in a spoke portion. With this horn switch, when the driver senses a danger, the small press button 53 must be reflexively pressed with the thumb or palm. For this reason, there is a possibility that the horn switch cannot be reliably operated in an emergency.

In order to solve such a problem, a horn switch has been devised in which a membrane switch is mounted on a planar portion of a steering pad and the membrane switch is turned on when the surface of the steering pad is pressed. . This membrane switch is shown in FIG.
In the well-known plate-shaped switch as shown in (a), a resin panel 71 in which a good conductor metal 72 such as a copper foil is vapor-deposited on the inner surface facing each other.
Then, when the surface pressure acts on the surface of the membrane switch 70, the surface of the membrane switch 70 is easily bent and deformed (see (b) of the same figure).

As shown in FIG. 1A, grid-like resin insulation layer spacers 73 are formed in the vertical and horizontal directions on the good conductor metal 72 on the inner surface of the resin panel, and two resin insulation layer spacers 73 are separated from each other by a predetermined distance. The resin panels 71 of the
Many contact points are formed between them. When the surface pressure acts on the resin panel 71 to cause bending deformation, the good conductor metal 72 at the facing position makes surface contact, and the circuit is closed (FIG. 12B).
reference). The membrane switch 70 can be used as a horn switch that is turned on by sticking it on the inner surface of the module cover 51 and lightly pressing the steering pad portion.

However, this type of membrane switch 70
In the horn switch in which the air bag is incorporated in the module cover 51, since the airbag is folded and accommodated in the module cover 51, the membrane switch 70 is provided at a position where a part of the airbag is loosely folded and accommodated.
There is a problem that the whole is deformed, the horn switch is difficult to operate, and the switch operates more sensitively than necessary at a position where the airbag is tightly housed.

In order to solve such a problem, an air bag device module cover 51 as shown in FIG. 13 has also been devised. This figure shows a cross section of the airbag device module cover 51. Two membrane switches 70 are mounted on the inner surface of the resin module cover 51 with a tear line 62 (planned cleavage line) interposed therebetween. At this time, the tear line is the module cover 5
Reference numeral 1 is a linear weak portion formed so as to be surely cleaved from a predetermined position by the internal pressure applied when the airbag is inflated. A support plate 63 having a substantially U-shaped cross section is housed at a position where the membrane switch 70 is supported between the inner surface of the module cover 51 and the module cover 51. The periphery of the support plate 63 is fixedly supported by a part of a retainer 65 that supports the inflator 64. Support plate 63 and inflator 64
An air bag 67 is folded into a predetermined shape and is tightly accommodated in the space 66 defined by the space. in this way,
By supporting the membrane switch 70 in the steering pad with the support plate 63, a uniform pressing force acts on the membrane switch 70 no matter which position on the steering pad surface is pressed. As a result, the reliability of the operation of the horn switch including the membrane switch 70 is improved, and the horn can be reliably operated even in an emergency.

[0008]

However, in the air bag device module cover shown in FIG. 13, since it is necessary to support the entire membrane switch 70 by the support plate 63, it is necessary to increase the size of the plate member. Therefore, the number of parts and the number of assembling steps also increase. In addition, the structure is complicated because the support plate 63 must be deformed immediately after the start of the inflation of the airbag to surely tear near the tear line 62 of the steering pad. Further, when the airbag is inflated and deployed and receives an internal pressure due to the inflation of the bag, the membrane switch 70 is sandwiched between the deformed support plate 63 and the cover, and the switch is continuously turned on. There is also a problem that keeps ringing.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art and to mount a horn switch in the steering pad so that the horn switch can be reliably operated. Another object of the present invention is to provide a module cover for an airbag device.

[0010]

In order to achieve the above object, according to the present invention, a membrane switch is mounted on the inner surface of a resin module cover to make a steering pad portion a horn switch, and an airbag module is housed inside. In the module cover for the airbag device,
A plate-like flap is integrally formed with the module cover main body on the inner surface of the module cover, and the plate-like flap and the membrane switch are formed by the locking means formed on the inner surface of the module cover by bending the plate-like flap. It is characterized in that it is fixed and supported at a predetermined position on the inner surface of the module cover.

At this time, two of the plate-like flaps are erected side by side along the tear line in the vicinity of the tear line formed on the inner surface of the module cover, and are bent to fix and support the membrane switch. It is preferable to do so.

[0012]

According to the present invention, in a module cover for an air bag device, a membrane switch is mounted on an inner surface of a resin module cover, a steering pad portion is used as a horn switch, and an air bag module is housed inside. A plate-like flap is integrally formed with the module cover main body on the inner surface of the cover, and the plate-like flap and the membrane switch are connected to each other by locking means formed on the inner surface of the module cover by bending the plate-like flap. By fixedly supporting the inner surface at a predetermined position, the membrane switch can be reliably fixedly supported in the module cover body with a small number of parts, and the horn switch can be reliably operated.

At this time, the plate-like flaps are installed upright side by side along the tear line at a position near the tear line formed on the inner surface of the module cover, and are bent to fix and support the membrane switch. This simplifies the work of fixing the membrane switch and saves labor.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an air bag device module cover according to the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is an exploded perspective view showing a state seen from an inner surface side for explaining an assembly structure of a synthetic resin module cover 10 which constitutes a steering pad. As shown in the figure, the driver cover side 11 of this module cover 10 is finished into a rounded curved surface of a predetermined shape. At four corners of the module cover 10, spoke connection portions 12 that are connected to spokes (not shown) of the steering wheel are formed. Further, at the position of the inner surface 18 of the module cover 10, a partition wall 13 for enclosing and fixing an airbag cushion or an inflator (not shown) at a predetermined position.
Are formed.

The partition walls 13 are formed at four locations along the periphery of the module cover 10 and are formed integrally with the module cover 10. A tear line 15 that is substantially H-shaped in a plan view is formed in an internal compartment 14 that is partitioned by the partition wall 13. The tear line 15 has a substantially V-shaped groove shape as shown in FIG. 3, and a linear groove bottom constitutes a thin portion of the module cover 10, and this portion is split when the airbag is inflated. Central tear line 15
A protective flap 16 for supporting a membrane switch, which will be described later, is provided upright at a position near the line extending in the direction of a. As shown in FIG. 1, when the membrane switch 20 is attached with the heat stake 30 formed on the inner surface 18 of the module cover 10 as a positioning pin, the protective flap 16 is bent outward as shown by an arrow A. The entire surface of the membrane switch 20 is covered.

FIG. 2 shows the module cover 1 shown in FIG.
It is a schematic plan view which showed the planar shape of 0. As shown in the figure, the two membrane switches 20 are fixed at the symmetrical positions with the central tear line 15a as the partition 13 and the heat stake 30 as positioning members, and are covered with the protective flap 16 to cover the inner surface of the module cover 10. It is fixed at 18.

FIG. 3A is a sectional view taken along the section line IIIa-IIIa shown in FIG. In order to fix the membrane switch 20 with the protective flap 16, the protective flap 16 is folded and overlapped on the membrane switch 20 arranged on the inner surface 18 of the module cover 10 as shown in FIG. Further, the fixing hole of the protective flap 16 may be fitted into the heat stake 30 formed in the vicinity of the partition wall 13, and the tip 30a of the heat stake 30 as the locking means may be slightly thermally deformed. This allows
Membrane switch 20, on the inner surface 18 of the module cover,
The protective flap 16 can be fixed integrally (see FIG. 3 (b)).

FIG. 4A shows a modification in which an L-shaped hook 31 is formed on the inner surface 18 of the module cover in place of the heat stake 30 shown in FIG. 3B. According to this L-shaped hook 31, when the protective flap 16 is bent outward (direction of arrow A), the attachment hole formed in the protective flap 16 and the tip of the L-shaped hook 31 are engaged with each other. Thus, the tip portion of the protective flap 16 can be fixedly supported by the L-shaped hook 31.

5 to 8 show the membrane switch 2 described above.
The structure of the T-slot lock 32 for fixing the membrane switch 21 smaller than 0 to the inner surface of the module cover 10 is shown. As shown in FIG. 5, the protective flap 16 is provided upright in the vicinity of the partition wall 13. Two T slots 33 are formed at the lower end of the protective flap 16. The T slot 33 is the module cover 1
By engaging with the T-shaped key 34 formed on the 0 side, the protective flap 16 can be maintained in a bent state. That is, as shown in FIG. 5, the opening 21a of the membrane switch 21 is aligned with the T-shaped key 34 and placed on the module cover 10, and in this state, the protective flap 16 is bent inward to lock the T slot 33 portion. By doing so, the membrane switch 21 and the protective flap 16 can be fixed to the inner surface 18 of the module cover.

FIG. 6 shows the T-slot lock 3 shown in FIG.
It is a top view of the module cover 10 which has 2. As shown in the figure, in this modification, a quadrangular membrane switch 21 that fits in the portion surrounded by the partition wall 13 is incorporated.

FIG. 7 is a sectional view taken along the line VII-VII shown in FIG. As shown in FIG. 7, the protective flap 16 is bent so as to cover the membrane switch 21 fixed to the inner surface of the module cover 10, and the T-slot lock 32 holds the bent state of the protective flap 16. 8A and 8B are explanatory views showing the configuration of the T slot lock 32 and the locking operation of the T slot lock 32. As shown in FIG. 8A, the T-slot 33 is composed of a wide slot portion 33a and a narrow slot portion 33b. The protective flap 16 is elastically deformed so that the head of the T-shaped key 34 is widened. It can be securely locked by inserting it into the slot 33a and sliding it laterally from the wide slot portion 33a. T on the inner surface of the module cover 10
The membrane switch 21 and the protective flap 16 can be integrally fixed to the inner surface 18 of the module cover by bending the protective flap 16 and engaging the T slot 33 with a part of the membrane switch 21 fixed to the character key 34. It is possible (see FIGS. 8B and 8C).

FIGS. 9 and 10 are explanatory views showing an example in which the membrane switch 20 shown above is applied to a steering pad. As shown in the figure, a membrane switch 20 functioning as a horn switch is housed in the center of the surface of the steering pad. Further, five auxiliary switches 40 are provided on each of the left and right sides of the horn switch position. This auxiliary switch 40
This is an ON / OFF switch using the membrane switch 20, and the position of the press button 41 is located at a position where the driver can extend his / her thumb while holding the steering wheel (not shown) as shown in FIG. Press button 41
Is composed of a thin portion 41a that can be easily deformed when pushed, and a projecting actuator button 41b that is pushed inward as the thin portion 41a is deformed. The thin portion 41a and the actuator button 41b are made of an integral transparent resin panel, and as shown in FIG. 9, a part of the cover is fitted in a rounded position. When the driver presses the press button 41, the projecting actuator button 41b on the back surface presses the surface of the membrane switch 20 to enable ON / OFF switching operation.

At the front position of the membrane switch 20, as shown in FIG. 10B, a backlight EL 42 is built in as illumination of the auxiliary switch 40. Furthermore, a signal line 43 for controlling the ON / OFF state of the 10 auxiliary switches 40 is led out from a part of the membrane switch 20, and extends from one position of the spoke connecting portion 12 through the steering pad together with the EL power supply line. Has been issued. A plug 44 for connecting to a wire harness (not shown) is attached to the tip of the signal wire 43. By configuring the steering pad in a composite manner with the horn switch and the auxiliary switch 40 as described above, the driver can reliably operate the horn switch provided on the steering pad portion, and the predetermined 10 auxiliary switches are provided. With 40, it is possible to easily set ON / OFF of various accessories even during operation.

[0024]

As is apparent from the above description, according to the present invention, when the horn switch made of the membrane switch is built in the module cover of the steering pad part in which the air bag is built, the number of parts is reduced.
It is possible to improve the certainty of the operation of the membrane switch.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an assembly example of an embodiment of a module cover for an airbag device according to the present invention.

FIG. 2 is a plan view showing an example of a module cover for an airbag device of the present invention.

FIG. 3 is a sectional view taken along a section line IIIa-IIIa shown in FIG.

FIG. 4 is a cross-sectional view showing a modified example of the locking means shown in FIG.

5 is an exploded perspective view showing a modified example of the airbag apparatus module cover of FIG. 1. FIG.

FIG. 6 is a plan view showing an example of a module cover for an airbag device of the present invention.

7 is a cross-sectional view taken along the line VII-VII shown in FIG.

FIG. 8 is a partially enlarged view showing details of locking means.

FIG. 9 is a plan view of a steering pad portion showing an application example of the airbag apparatus module cover according to the present invention.

10 is a sectional view taken along the line XX shown in FIG.

FIG. 11 is a front view showing an example of a conventional steering pad that accommodates an airbag module.

FIG. 12 is a partially enlarged view showing an example of a known membrane switch.

FIG. 13 is a sectional view showing a conventional example of a horn switch in which a membrane switch is supported by a support plate.

[Explanation of symbols]

 10 Module Cover 13 Partition 15 Tear Line 16 Protective Flap 20, 21 Membrane Switch 30 Heat Stake 31 L-shaped Hook 32 T Slot Lock

Claims (2)

[Claims] 1. A module cover for an air bag device, wherein a membrane switch is mounted on the inner surface of a resin module cover, a steering pad portion is used as a horn switch, and an air bag module is housed therein. -Shaped flap is integrally molded with the module cover main body, and the plate-shaped flap and the membrane switch are fixed at predetermined positions on the inner surface of the module cover by a locking means formed by bending the plate-shaped flap and formed on the inner surface of the module cover. A module cover for an airbag device, characterized in that it is fixedly supported by the module cover. 2. The plate-shaped flaps are installed upright side by side along the tear line in the vicinity of a tear line formed on the inner surface of the module cover, and are bent to fix and support the membrane switch. The module cover for an airbag device according to claim 1, wherein