JPH07147115A - Push button switch - Google Patents

Abstract

PURPOSE:To provide a push switch normally closed which has high reliability, compact size, and can be manufactured at low cost. CONSTITUTION:A projected and formed part 22 of a push button switch is nearer to a push button 15 than to a fixed contact part 20 and unitedly projected out of an inner wall of a storage chamber 10a in the way the part 22 is in parallel to the longitudinal direction of the fixed contact point 20. The part 22 has a semi-ellipse shape with the major axis in the vertical direction and in the normal condition wherein no pushing operational force is applied, the upper end position is set to be lower than that of the fixed contact part 20 with which a movable contact part 15 is to be brought into contact and the height of the projected part out of the inner wall is set to be higher than the projected height of the fixed contact part 20 and furthermore, a taper face 22a which becomes higher downward is formed in the upper end part. The taper face 22a has a function as a guide to mount the tip part of the movable contact part 15 on the surface of the projected and formed part 22 when the push button 17 is pushed and also has a function as a guide to transfer the movable contact part 15 to the fixed contact part 20 at the time of returning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a push button switch.

[0002]

2. Description of the Related Art As a push button switch of this type using a coil spring, the present inventors have already filed Japanese Patent Application No. 5-88364.
Some of them were filed as issues. This push button switch is shown in Figure 2.
A normally open type having a structure as shown in (a) and (b),
When the push button 17 is pressed, the storage chamber 1 in the switch body 10
Depressing operation portion 16 of the coil spring 12 arranged at 0a
Is pushed down as the push button 17 moves downward, and by this pushing down, the movable contact portion 15 formed integrally with the coil spring 12 also moves downward while twisting the coil spring 12. By this movement, the outer surface of the movable contact portion 15 rides on and elastically contacts the spherical surface of the fixed contact portion 20 formed on the rising piece of the conductive plate 19 exposed on the inner surface of the storage chamber 10a. That is, the movable contact portion 15 and the fixed contact portion 2
0 is electrically conducted to switch on. Therefore, the terminals 14 integrally formed on the conductive plate 13 on which the coil spring 12 is mounted and the terminals 21 integrally formed on the conductive plate 19 are energized.

Next, when the pressing force of the push button 17 is released, the tip of the movable contact portion 15 moves upward due to the return of the twisted state of the coil spring 12, and the movable contact portion 15 is separated from the fixed contact portion 20 to be switched off. . Further, at this time, the push button 15 has the movable contact portion 1
With the upward movement of the tip portion of No. 5, the pushing operation portion 16 pushes it upward to return it to its original position. Reference numeral 11 in the figure denotes a cover attached to the upper opening of the switch body 10.

Therefore, by utilizing the structure of the push button switch described above, the position of the fixed contact portion 20 is moved upward to push the push button 17
The movable contact part 15 comes into contact with the fixed contact part 20 when the push button 17 is pushed up, and the movable contact part 15 separates from the fixed contact part 20 when the push button 17 is pushed down. Normally closed type shown in FIGS. The present inventors have made a push button switch of.

[0005]

However, in the structure of the normally closed push button switch described above, when the push operation of the push button 15 is released and the movable contact portion 15 is returned, as shown in FIG. It suffices that the movable contact portion 15 rides on the surface of the fixed contact portion 20 better than the lower end of the contact portion 20, but there is a risk that the movable contact portion 15 may be caught at the lower end of the fixed contact portion 20 and malfunction.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a normally closed push button switch which is highly reliable and can be manufactured in a small size and at a low cost.

[0007]

In order to achieve the above object, the present invention is provided between a conductive plate disposed at the bottom of a storage chamber formed in a switch body and inner wall surfaces on both sides of the storage chamber. A coil spring arranged on the conductive plate in a compressed form,
A movable contact portion formed by extending from one end of the coil spring to the inner wall surface on one side of the storage chamber so as to be parallel to the inner wall surface of the storage chamber in the direction of the ceiling portion of the storage chamber, and penetrating inside and outside the ceiling portion of the storage chamber. The push-up portion provided at the tip of the movable contact portion pushes one end of the housing chamber side up by the elastic force of the coil spring and the other end projects out of the switch body. A push button, a fixed contact portion protruding from the inner wall surface on one side of the storage chamber and brought into contact with the movable contact portion in a state where the push button is pushed up by the elastic force of the coil spring, and a fixed contact portion closer to the push button than the fixed contact portion. And a protruding molding portion projectingly provided on the inner wall surface of the storage chamber so as to be parallel to the longitudinal direction of the fixed contact portion, and the protruding molding portion pushes up the upper end position of the push button by the elastic force of the coil spring. Contact the above movable contact part The lower part of the fixed contact part is located below the fixed contact part, and a taper surface is formed at the upper end of the fixed contact part. The movable contact portion is freely transferable.

[0008]

According to the present invention, since the movable contact portion can be transferred between the fixed contact portion and the protrusion molding portion while being guided by the tapered surface of the protrusion molding portion, a defective switch operation does not occur. Since the protruding molded part is provided at a position closer to the push button than the fixed contact part, when the movable contact part of the push button is pushed down, the protruding molded part acts as an operation guide to improve the operation position accuracy, and further, the fixed contact part is coiled. The contact pressure can be increased because it is closer to the spring.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment. A switch body 10 made of a resin molded product has a box-like shape with an opening on the upper surface, and the internal space is a storage chamber 10a, and the opening of the storage chamber 10a is a cover made of a thin metal plate. 11 is attached to the ceiling of the storage chamber 10a.

A coil spring 12 is arranged so as to be compressed by the inner wall surfaces on both sides on the conductive plate 13 exposed at the bottom between the inner wall surfaces on both ends at one end of the storage chamber 10a. It is electrically connected to the plate 13. Conductive plate 1
Reference numeral 3 is an element that is inserted when the switch body 10 is molded.
It projects from one end surface of 0 to the outside.

The coil spring 12 has one end parallel to the inner wall surface on one side of the storage chamber 10a with a certain gap therebetween and is in parallel with the cover 1.
The movable contact portion 15 is extended in one direction, and the tip of the extension portion constitutes the movable contact portion 15. Further, the extension portion is bent in the width direction, and this portion constitutes the pressing operation portion 16 of the push button 17. The cover 11 is provided with a round hole 18 through which the push button 17 is vertically movably inserted, and a cylindrical push button 17 is vertically movably inserted into the round hole 16. Here, the round hole 18 has a rounded edge that is bent downward to form a tubular portion 18a, which is rounded to prevent the push button 17 from being scraped by the round edge of the opening when the push button 17 is moved up and down. , Again the tubular portion 18a
Is used as a guide for the vertical movement of the push button 17 in order to stabilize the operability of the push button 17. Further, one end of the cover 11 is bent into an L shape so that the cover 11 hangs down into the storage chamber 10a.
The coil spring 12 is pressed and fixed by the tip of the. An insulation coating, an insulation tape, or a molded product is used to insulate between the pressing and fixing portion and the coil spring 12.

On the other hand, the push button 17 is provided with a retaining collar portion 17a on its lower peripheral portion so as not to fall off from the hole 18, and an annular groove 17b into which the tip of the cylindrical portion 18a is fitted is formed on the upper surface of the collar portion 17a. It is provided. The push button 15 is constantly pushed upward by the pushing operation portion 16 of the coil spring 12 so that the head portion 17c is projected to the outside of the switch body 10.

In the fixed contact portion 20 which is opened and closed by the movable contact portion 15, a part of the vertical piece of the conductive plate 19 inserted in the one side wall of the storage chamber 10a is moved from the inner wall surface of the storage chamber 10a to the storage chamber 10a side. It is formed by bulging,
Its shape is an elliptic hemisphere whose longitudinal direction is long, and the position of the tip portion parallel to the inner wall surface is inside the outer surface of the movable contact portion 15, and the formation position is closer to the coil spring 12 side than the central axis of the push button 17. It is set at a position where the movable contact portion 15 comes into contact with the substantially central portion of the surface in a deviated position and in a normal state where no pressing operation force is applied. The conductive plate 19 is disposed on the bottom surface of the other end side of the storage chamber 10a by inserting a part of the horizontal piece integrally connected to the vertical piece into the bottom wall of the storage chamber 10a, and is integrally formed with the terminal. 21 is projected to the outside from the other end surface of the switch body 10.

On the other hand, the storage chamber 10a is located closer to the push button 15 than the fixed contact portion 20 and parallel to the longitudinal direction of the fixed contact portion 20.
A protruding molding portion 22 is integrally provided on the inner wall surface of the. The protruding molding portion 22 has an elliptic hemispherical shape whose longitudinal direction is long, and the movable contact portion 1 is in a normal state in which the pressing operation force is not applied to the upper end position.
5 is below the position of the fixed setting portion 20 in contact with the fixed contact portion 20, and the protruding height from the inner wall surface is higher than the protruding height of the fixed contact portion 20. Further, the upper end portion has a tapered surface which becomes higher as it goes downward. 22a is formed.

Therefore, in the push button switch of the present invention, when the push button 17 is not pushed, an upward force is generated in the movable contact portion 15 by the elastic force of the coil spring 12, and the push button is pushed through the pushing operation portion 16. 17 is pushed up to the state shown in FIG. 1 (b), and the movable contact portion 15 has a surface view in the middle of the fixed contact portion 20 shown in FIG. 1 (c).
It is in a state of elastic contact as shown in. Terminal 1 in this state
4, a circuit of the conductive plate 13, the coil spring 12, the movable contact portion 15, the fixed contact portion 20, the conductive plate 19, and the terminal 21 is formed. That is, it is in a switch-on state.

Next, when the push button 17 is pushed down, the coil spring 1
The second pressing operation portion 16 is pushed down with the downward movement of the push button 17, and by this pushing down, the movable contact portion 15 moves downward while sliding a part of the movable contact portion 15 onto the surface of the fixed contact portion 20, and eventually the movable contact portion. The tip end portion of 15 is guided by the tapered surface 22a of the protrusion forming portion 22 and rides on the surface of the protrusion forming portion 22 as indicated by the broken line in FIG. 1C. In this riding state, the protruding height of the protruding molding portion 22 is higher than the protruding height of the fixed contact portion 20, so that the movable contact portion 15 is separated from the fixed contact portion 20. In other words, the above circuit is cut off and the switch is turned off.

When the pushing down force applied to the push button 17 is released, the movable contact portion 15 moves upward due to the return of the twisted state of the coil spring 12, and the movable contact portion 15 riding on the protruding molding portion 22. While the tip end part of the movable contact part 15 comes down from the tapered molding part 22 while slidingly contacting the protruding molding part 22 and separates from the protruding molding part 22, the part of the movable contact part 15 corresponding to the fixed contact part 20 becomes the fixed contact part 20. It will come into contact and return to the original switch-on state.

[0018]

According to the present invention, since the movable contact portion configured as described above can be transferred between the fixed contact portion and the protrusion molding portion while being guided by the tapered surface of the protrusion molding portion, the switching operation can be performed. Since there is no defect and the protruding molded part is provided at a position closer to the push button than the fixed contact part, when the movable contact part of the push button is pushed down, the protruding molded part acts as an operation guide, and the operation position accuracy becomes high, Further, since the fixed contact portion is closer to the coil spring, the contact pressure can be increased, and the structure is simple, so that it is possible to provide a compact and highly reliable normally-closed pushbutton switch. .

[Brief description of drawings]

FIG. 1A is a top view of an embodiment of the present invention with a cover removed. (B) is a side sectional view of the above.
(C) is sectional drawing of the principal part same as the above.

FIG. 2A is a top view of a conventional example with a cover removed. (B) is a side sectional view of the above.

FIG. 3A is a top view of a conventional example with a cover removed. (B) is a side sectional view of the above. (C) is sectional drawing of the principal part same as the above.

[Explanation of symbols]

 10 Switch Main Body 10a Storage Chamber 11 Cover 12 Coil Spring 13 Conductive Plate 14 Terminal 15 Movable Contact Part 16 Push Operation Part 17 Push Button 17a Head Part 18 Round Hole 19 Conductive Plate 20 Fixed Contact Part 21 Terminal 22 Projected Molded Part 22a Tapered Surface

Claims (1)

[Claims] 1. A conductive plate disposed at the bottom of a storage chamber formed in the switch body, and a coil spring disposed on the conductive plate in a compressed form between inner wall surfaces on both sides of the storage chamber. A movable contact portion extending from the one end of the coil spring to the inner wall surface on one side of the storage chamber in parallel to the ceiling portion of the storage chamber so as to be parallel to the inside wall of the storage chamber. It is inserted into a hole formed so as to penetrate, and one end of the storage chamber side is pushed up by the pushing-up part provided at the tip of the movable contact part by the elastic force of the coil spring and the other end projects out of the switch body. A push button, a fixed contact portion that is projected from the inner wall surface on one side of the storage chamber and is brought into contact with the movable contact portion when the push button is pushed up by the elastic force of the coil spring, and a push button closer to the fixed contact portion than the fixed contact portion. So that it is parallel to the longitudinal direction of the fixed contact A fixed contact which is provided on the inner wall surface of the storage chamber so that the movable contact portion comes into contact when the push button is pushed up by the elastic force of the coil spring. The taper surface is formed at a position lower than the position of the above-mentioned part and becomes higher in the upper end part thereof, and the fixed contact part and the protrusion forming part are in movable contact when the movable contact part is moved up and down. A push button switch characterized in that the parts can be freely transferred.