JP2002075112A - Press-button switching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a press-button switching device of a simplified form control, leading to reduction in cost. SOLUTION: A switching device is fixed to a state plate, which is turned on/off through pressurizing with a pressurizing shaft of a press-button supported by a press-button support member for pressurizing operation. The stage plate absorbs excessive pressurizing force to the switch device by the pressurizing operation with the press-button.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a push button switch device.

[0002]

2. Description of the Related Art For example, in a push button switch device using a general-purpose tact switch as a switch device, a push button is pressed to elastically deform a disc spring of the tact switch by a pressing shaft portion of the switch. Is turned on and off. The push button is made of a hard material such as metal or synthetic resin in order to elastically deform the disc spring at the pressing shaft portion. In such a push button switch device, the distance (stroke of the push button) by which the push shaft can move toward the inside of the support wall when the push button is pushed is determined by the push button in consideration of poor contact and the like. In the normal state where the pressing operation is not performed, the distance from the tip of the pressing shaft portion to the electric contact piece, that is, the distance that the pressing shaft portion moves to turn on the tact switch (stroke to turn on the tact switch) is slightly larger than the distance. Have been.

[0003] A click feeling is transmitted to the operator when the disc spring is elastically deformed. Since the push button is constantly urged upward by the compression spring, the operator pushes the push button more than necessary. Further, since the stroke of the push button is larger than the stroke of turning on the tact switch, the pressing shaft portion of the push button can be further moved inside the support wall even after the tact switch is turned on by elastically deforming the disc spring of the tact switch. For this reason, even if the operator obtains a click feeling, the operator presses the push button, and as a result, an excessive pressing force is applied to the tact switch.
Then, since the push button is made of a hard material, there is a possibility that the disc spring of the tact switch is damaged by the pressing shaft portion of the push button.

Conventionally, in order to prevent these, the shape of the pressing shaft portion of the push button or the mounting position of the base plate is adjusted so that the stroke of the push button does not become excessively large than the stroke for turning on the tact switch. I did, but it was negative in terms of labor and cost. This problem also exists to a greater or lesser extent with switch devices other than tact switches.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a push button switch device which does not require strict shape management and position management and leads to cost reduction based on the above problem awareness.

[0006]

SUMMARY OF THE INVENTION The present invention provides a push button having a push shaft portion supported by a push button support member so as to be able to be pushed;
And a base plate on which a switch device that is turned on / off by a pressing operation of the pressing shaft of the push button is fixed. In the push button switch device, excessive pressing of the base plate to the switch device by the pressing operation of the push button is performed. It is characterized in that it is configured to absorb pressure. According to this device, the base plate absorbs the excessive pressing force applied to the switch device due to the difference between the stroke of the push button and the stroke of turning on the switch device, thereby preventing the switch device from being damaged due to the pressing force. Strict shape management and position management are not required.

According to a more specific aspect of the present invention, the base plate can be constituted by a cantilever type base plate having one end fixed and a switch device at the other end and having a cantilever type. According to this device, the excessive pressing force applied to the switch device can be absorbed by the difference between the stroke of the push button and the stroke of turning on the switch device due to the resiliency of the cantilever type base plate. There is no need for shape management or position management.

According to another more specific aspect of the present invention, when the switch device is pressed by the pressing shaft portion of the push button between the base plate and the switch device, the switch device is mounted on the base plate. It is possible to have a compressible elastic member that allows access. According to this device, due to the compressible elastic member interposed between the switch device and the base plate, excessive pressing force applied to the switch device due to the difference between the stroke of the push button and the stroke for turning on the switch device. Strict shape management and position management are not required. As the compressible elastic material, sponge or rubber can be used.

As the switch device, for example, a general-purpose tact switch can be used.

[0010]

FIG. 1 shows a first embodiment of a push button switch device according to the present invention. Push button support wall 10
Is formed with a cylindrical portion 11 having a bottom portion 12. A shaft hole 13 is formed in the center of the bottom 12. Shaft hole 13
The inner peripheral portion of the inner cylindrical portion 14 extends toward the outside of the support wall 10.
Are formed.

The push button 20 is a disc-shaped pressing operation unit 2.
1, a pressing shaft portion 22 protruding from the center of the pressing operation portion 21 toward the circuit board 30, and a cylindrical body 23 concentric with the pressing shaft portion 22. The cylindrical body 23 is slidably fitted between the tubular portion 11 and the inner tubular portion 14 of the push button support wall 10. This push button 20 is
2 is urged in a protruding direction by a compression spring 24 located around the periphery of the shaft 2, and the protruding end is regulated by a retaining ring 25 fixed to the protruding end of the pressing shaft 22 from the support wall 10.

The base plate 40 has a support wall 10 at one end thereof.
A screwing portion 41 for fixing to the inside fixing portion 10X is formed. One end of the base plate 40 is fixed to the fixing portion 10X by the screwing portion 41 and the fixing screw 43, and the other end is free. That is, the base plate 40 is supported in a cantilever manner, and the circuit board 30 is fixed to the surface (the upper side in the figure) on the free end side. On the cantilever base plate 40A, a thin portion 42 is formed in a portion between the region where the circuit board 30 is fixed and the screw portion 41.

On the circuit board 30, there is provided a tact switch 50 which is turned on and off by the pressing shaft portion 22 so as to match the position of the pressing shaft portion 22 of the push button 20. The thin portion 42 of the cantilever base plate 40A is
It is intended to facilitate the elastic deformation of the push button 20A.
Even if the gap between the pressing shaft 22 and the tact switch 50 is slightly uneven, that is, even if the gap between the tip of the pressing shaft 22 and the tact switch 50 is the longest,
The tact switch 50 can be operated, and the cantilever base plate 40A is bent even when the interval is shortest, so that the tact switch 50 can be turned on and off without being damaged. Of course, by selecting the material and thickness of the cantilever base plate 40A, it is possible to give the same bending characteristics to the cantilever base plate 40A without forming the thin portion 42.

An example of the configuration of the tact switch 50 will be described with reference to FIGS. The tact switch 50 has a box-shaped case member 51 and an elastically deformable disc spring 52 formed of a part of a spherical surface. The case member 51 has a flat circular recess 53 in which the disc spring 52 is mounted at the center. Are formed. In the case member 51, a pair of electric contact pieces 55a and 55b, each of which exposes a portion to be soldered to the circuit board 30, are embedded and supported. The electric contact piece 55a has a convex portion 56 located in the opening 54 communicating with the concave portion 53, and the electric contact piece 55b has a circular contact portion 57 located at the bottom of the concave portion 53.

The disc spring 52 is provided with a projection 56 of the electric section 55a.
And the insulating portion 58 of the case member 51, and is placed so as to always conduct to the convex portion 56 and not to contact (turn off) the circular contact portion 57. When the disc spring 52 is pressed by the pressing shaft 22 of the push button 20, the disc spring 52 elastically deforms and contacts the circular contact portion 57 of the electric section 55b while maintaining the contact with the projection 56 of the electric section 55a. As a result, the electric pieces 55a and 55b conduct (ON). The tact switch 50 is fixed to the circuit board 30 and the cantilever base plate 40A by fixing screws 31.

The cantilever base plate 40A having the above tact switch 50 is positioned so that the center of the tact switch 50 at its free end is located immediately below the pressing shaft portion 22 of the push button 20, and one end of the tact switch 50 is screwed. The fixing screw 43 is screwed in from the portion 41 to be fixed to the fixing portion 10 </ b> X inside the support wall 10.

The final push button switch device having the above configuration is
When the pressing operation portion 21 of the push button 20 is pressed while compressing the compression spring 24, the pressing shaft portion 22 moves toward the circuit board 30, and the tip portion contacts the disc spring 52 of the tact switch 50. When the pressing operation on the pressing operation portion 21 is continued, the pressing shaft portion 22 of the push button 20 elastically deforms the disc spring 52 of the tact switch 50 so that the back surface of the disc spring 52 is located directly below the disc spring 52 in a circular contact portion 57. (FIG. 5). The disc spring 52 is connected to the electric contact piece 5 via the projection 56.
5a, and the circular contact portion 57 is provided on the electric contact 55b.
5b conducts. At the same time, a click feeling is transmitted to the operator.

The pressing force for bending (the thin portion 42 of) the cantilever base plate 40A is intermediate between the pressing force required for elastically deforming the disc spring 52 of the tact switch 50 and the pressing force that the disc spring 52 can tolerate. Of the cantilever base plate 40A
It is preferable to set (select) the characteristics of the (thin portion 42).
By doing so, it becomes possible to flex the cantilever base plate 40A with an excessive pressing force applied to the tact switch 50 when the push button 20 is pressed more than necessary (FIG. 1).
(C)) The damage of the disc spring 52 of the tact switch 50 can be prevented. Further, the operator can obtain the feeling of pushing the push button 20 completely without damaging the disc spring 52 of the tact switch 50.

FIG. 2 shows a second embodiment of the push button switch device of the present invention. The second embodiment is different from the first embodiment in that the base plate 40 is cantilevered,
The base plate itself is a double-sided base plate 40B.
0B and the tact switch 50 fixed on the two-sided base plate 40B in that a compressible elastic member 60 is interposed. The other parts have the same configuration as the first embodiment, and the same members are denoted by the same reference numerals and description thereof will be omitted.

The elastic member 60 is made of a sponge 60a, and is formed in a substantially same rectangular shape as the case member 51 of the tact switch 50.

In the second embodiment, when the pressing operation portion 21 of the push button 20 is pressed, the pressing operation portion 21 elastically deforms the disc spring 52, as in the first embodiment. 55a and the electric contact piece 55b conduct.
At the same time, a click feeling is transmitted to the operator.

The pressing force for compressing the sponge 60a as the elastic member 60 is set to an intermediate value between the pressing force required for elastically deforming the disc spring 52 of the tact switch 50 and the pressing force allowable by the disc spring 52. And sponge 60a
Is preferably set (selected). By doing so, it is possible to compress the sponge 60a with an excessive pressing force applied to the tact switch 50 when the push button 20 is pushed more than necessary (FIG. 2C), and the disc spring of the tact switch 50 52 can be prevented from being damaged. Further, the operator can obtain the feeling of pushing the push button 20 completely without damaging the disc spring 52 of the tact switch 50.

In the above second embodiment, the elastic member 60
Although the sponge 60a was used as an example, an elastic member other than the sponge such as rubber may be used as long as it is a macroscopically compressible elastic member.

[0024]

As described above, according to the present invention, it is possible to obtain a push button switch device which does not require strict shape management and position management and leads to cost reduction.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C are cross-sectional views showing different states of a first embodiment of a push-button switch device to which the present invention is applied.

FIGS. 2A, 2B, and 2C are cross-sectional views showing different states of a push-button switch device according to a second embodiment of the present invention.

FIG. 3 is a plan view of the tact switch used in the first and second embodiments.

FIG. 4 is a sectional view taken along the line IV-IV in FIG.

5 is a sectional view taken along line IV-IV in FIG. 3 in a state different from FIG. 4;

FIG. 6 is a perspective view of the tact switch of FIGS. 3 to 5;

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 6;

FIG. 8 is a cross-sectional view taken along line VII-VII of FIG. 6 in a state different from FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Support wall 10X Fixed part 11 Cylindrical part 12 Bottom part 13 Shaft hole 14 Inner cylindrical part 20 Push button 21 Depressing operation part 22 Depressing shaft part 23 Cylindrical body 24 Compression spring 25 Retaining ring 30 Circuit board 31 Fixing screw 40 Base plate 40A Cantilever base plate 40B Double support base plate 41 Screw fixing part 42 Thin part 43 Fixing screw 50 Tact switch 51 Case member 52 Disc spring 53 Depression 54 Opening 55a Electric contact piece 55b Electric contact piece 56 Convex part 57 Circular contact part 58 Insulation Part 60 elastic member 60a sponge

Claims (4)

[Claims] 1. A push button having a pressing shaft portion supported by a push button supporting member so as to be able to be pressed, and a base plate to which a switch device which is turned on and off by a pressing operation of the push button by the pressing shaft portion is fixed; The push button switch device according to claim 1, wherein the base plate is configured to absorb an excessive pressing force on the switch device due to a pressing operation of the push button. 2. The push button switch according to claim 1, wherein the base plate is a cantilever type spring base plate having one end fixed and a switch device at the other end. apparatus. 3. The push button switch device according to claim 1, wherein the switch device approaches the base plate between the switch plate and the switch device when the switch device is pressed by a pressing shaft portion of the push button. Pushbutton switch device having a compressible elastic member that allows 4. The push-button switch device according to claim 1, wherein said switch device is a general-purpose tact switch.