JPH0515015B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a push button switch for a keyboard used in an operation panel section of an electronic device.

Conventional configurations and their problems In recent years, electronic devices have been increasingly computerized, and push button switches used in the operation panels of electronic devices are low in cost and have an excellent operating feel. requested. As a conventional example of this,
An insulating substrate 2 with a fixed contact 1 as shown in FIG.
On top, a rubber sheet 5 is arranged, which has a movable contact 3 in a portion corresponding to the fixed contact 1 and a movable part 4 pushed out so as to protrude upward, and the movable part of the rubber sheet 5 is arranged. 4 and a push button 8 which is integrally molded with the frame 6 and held in a window hole 7 of the frame 6. Note that the amount by which the push button 8 protrudes from the frame 6 cannot be increased due to problems in the design of the operation panel section and usability. Then, as shown in FIG. 2, by pressing the push button 8 with a fingertip until it is approximately flush with the frame 6, the movable part 4 of the rubber sheet 5 integrally formed with the push button 8 is sagged. , the switch was switched by electrically connecting the movable contact 3 provided on the movable part 4 and the fixed contact 1 on the insulating substrate 2.

However, in the above structure, as mentioned above, the gap between the window hole 7 of the frame 6 and the push button 8 was simply reduced to about 0.2 mm as a countermeasure to the demand for an excellent operating feel. Moreover, since the amount of protrusion of the push button 8 from the window hole 7 is not large, as shown in FIG.
There is a problem that the corner 9 of the push button 8 gets stuck on the push button 8, and when the push button 8 is released, the push button 8 does not return smoothly.
The problem was that the push button 8 did not return smoothly.

Purpose of the Invention The present invention is intended to eliminate the above-mentioned problems, and when switching is performed by pressing a pushbutton with a small amount of protrusion from the frame, even if the pushbutton hits the window hole of the frame, the pushbutton remains smooth. The object of the present invention is to provide a highly reliable push button switch that enables easy return.

Structure of the Invention In order to achieve this object, the push button switch of the present invention includes an insulating substrate having a fixed contact, and a movable part pushed out so as to protrude upward in a portion corresponding to the fixed contact. an elastic sheet disposed on a substrate; a movable contact provided on the inner surface of the movable part that makes contact with and separates from the fixed contact; and a movable contact provided on the inner surface of the movable part with a thickness slightly lower than that of the movable contact. The dowel is provided so as to be integrally or constantly in contact with the upper surface of the movable part, and is further provided slightly in the window hole of the frame attached to the insulating substrate so that the upper surface is approximately flush with the upper surface of the frame during switching. It consists of a push button fitted so as to protrude from the frame.

As mentioned above, by providing a dowel slightly lower than the thickness of the movable contact on the inner surface of the movable part placed on the elastic sheet, the elasticity of the dowel allows the pushbutton to be pushed diagonally downwards and the pushbutton gets stuck. Even if the push button is pressed, it is possible to return the push button to its original state.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 4 to 7.

First, in the embodiment shown in FIG. 4, reference numeral 11 denotes an insulating substrate having a fixed contact 12, on which a movable contact 13 is provided at a portion corresponding to the fixed contact 12, and is pushed out so as to protrude upward. A rubber sheet 16 provided with a movable part 14 is disposed, and a movable contact 1 is placed on the inner surface of the movable part 14 of this rubber sheet 16.
A dowel 15 having a thickness slightly lower than that of the movable contact 13 is provided so as to surround the movable contact 13.

In addition, this rubber sheet 16
The switch is integrally formed with the frame 17, is held in the window hole 18 of the frame 17, and is held in the window hole 18 of the frame 17 during switching.
A push button 19 is provided that slightly protrudes from the frame 17 so as to be substantially flush with the frame 17. With this configuration, as shown in FIG. 5, by pressing the push button 19 with a fingertip, the movable portion 14 of the rubber sheet 16 integrally molded with the push button 19 is bent, and the movable portion 14 is bent. Switching is performed by electrically conducting between the provided movable contact 13 and the fixed contact 12 on the insulating substrate 11 (at this time, the top surface of the push button 19 and the top surface of the frame 17 are approximately on the same plane).
Further, when the pressing force from the fingertip is released, the push button 19 returns to its upward movement due to the elasticity of the movable portion 14 of the rubber sheet 16. In addition, as shown in FIG.
When pushed diagonally downward strongly, the elasticity of the movable portion 14 of the rubber sheet 16 and the elasticity of the dowel 15 provided on the inner surface of the movable portion 14 are added, so that the push button 19 smoothly returns to its upward movement.

Since the push button switch according to the embodiment of the present invention is configured as described above, the push button 19 is strongly pressed diagonally downward, and the push button 19 is pushed into the window hole of the frame 17.
8, the elasticity of the dowel 15 allows the push button 19 to return to its upward movement smoothly. Further, since the dowel 15 is integrally molded with the rubber sheet 16, an inexpensive push button switch can be obtained.

Effects of the Invention As described above, according to the present invention, even in a push button switch where the amount of protrusion of the push button from the frame cannot be increased due to design constraints, the inner surface of the movable part of the rubber sheet is thicker than the thickness of the movable contact. Due to the slightly low elasticity of the dowel, even if the push button gets stuck in the window hole of the frame, the push button can be smoothly returned to its upward movement, thereby providing a highly reliable push button switch. can.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a conventional push button switch, Figure 2 is a sectional view showing the state of the conventional push button switch when it is operated, and Figure 3 is a sectional view of the conventional push button switch when the push button is pressed diagonally downward. 4 is a sectional view showing an embodiment of the push button switch of the present invention; FIG. 5 is a sectional view showing the state of the push button switch of the present invention when it is operated; 6
The figure is a cross-sectional view showing the push button of the push button switch of the present invention when the push button is pressed diagonally downward, and FIG. 7 is a bottom view showing an enlarged main part of the push button switch of the present invention. 11... Insulating board, 12... Fixed contact, 13...
...Movable contact, 14...Movable part, 15...Dowel, 1
6...Rubber sheet, 17...Frame, 18...
Window hole, 19...push button.

Claims (1)

[Claims] 1. An insulating substrate having a fixed contact, an elastic sheet disposed on the insulating substrate having a movable part pushed upward in a portion corresponding to the fixed contact, and an elastic sheet provided on the inner surface of the movable part. a movable contact that comes into contact with and separates from the fixed contact; a dowel that is provided at the inner end of the movable part to be slightly lower than the thickness of the movable contact; and a dowel that is provided so as to be integrally or always in contact with the upper surface of the movable part. In addition, in the window hole of the frame attached to the above insulating board,
A pushbutton switch that is fitted with a pushbutton that slightly protrudes from the frame so that the top surface is substantially flush with the top surface of the frame during switching.