JPH09198962A - Rubber contact switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber contact switch where a push button part is formed in a single piece with a rubber contact, in which a push pin and a guide part are eliminated by equipping itself with a function of forced linear motion to lead to decrease the number of component parts and enhancement of the easiness in assembling. SOLUTION: A push button part 5 in the central part is coupled with a rubber sheet through a coupling part 6 so that a rubber contact 3 is formed. The coupling part 6 is configured with an oversurface 7, an undersurface 8 parallel with and having the same length as the oversurface 7, and vertical walls 9 connected with the side edges of the oversurface 7 and undersurface 8 so that the whole assumes an surface unevenness. The oversurface 7 and undersurface 8 constitute a parallel link mechanism, and the push button part 5 makes linear motions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber contact switch in which a rubber contact is integrally formed on a rubber sheet.

[0002]

2. Description of the Related Art As a rubber contact switch of this type, there is one having a structure shown in FIGS.
-12956 gazette).

In the rubber contact switch of the first conventional example shown in FIG. 5, a rubber sheet 2 is attached on a wiring board 1, and a rubber contact 3 is formed on the rubber sheet 2. The guide portion 20 of the case 13 is provided with a pair of push pins 21, and the lower ends of the push pins 21 are in contact with the rubber contact 3.

The contact end 22 of the key top 15 swingably supported by the case 13 is in contact with the upper end of the push pin 21.

When the key top 15 is oscillated, the push pin 21 descends along the guide 20 and presses the rubber contact 3 to switch it on, and when the pressing is released, it is switched off by the restoring force of the rubber contact 3. Becomes

In the rubber contact switch of the second conventional example shown in FIG. 6, a rubber contact 3 is formed on the surface of a rubber sheet 2 and a push button portion 5 is integrally formed on the rubber contact 3. A push pin portion 23 is integrally formed on the button portion 5.

[0007]

Generally, the rubber contact of a rubber contact switch must be pressed by a linear motion from a direction perpendicular to the switch contact in order to ensure the switch operation. The rubber contact switch of the first conventional example is provided with the push pin 21 guided by the guide portion 20 in order to change the key top 15 to the linear motion because the key top 15 is the oscillating motion.

Therefore, in the rubber contact switch of the first conventional example, the push pin 21 and the guide portion 20 are required, so that the number of switch components increases, the assembly becomes complicated, and the cost increases.

The structure of the second conventional example is simpler than that of the first conventional example, but since the rubber contact 3 is composed of one thin dome-shaped rubber plate, only the upper and lower parts can be formed. Not easy to displace in any direction. Therefore, if the operation direction of the push pin 23 is bent even a little, the linear motion does not occur accurately, and the phenomenon that the switch contacts 10 and 11 are not sufficiently close to each other is likely to occur.

Therefore, in the second conventional example, the push pin portion 23 is formed of a slidable resin material, and the push pin portion 2
The switch device is configured to guide 3 by the operation guide tube.

Therefore, the second conventional example also requires the two-color molding using different resin materials, the number of switch components increases, the assembly becomes complicated, and the cost increases. Not done.

The present invention has been made by paying attention to the above-mentioned point, and the push button portion is a rubber contact integrally formed by using the same resin material, and has a function of the forced linear movement itself. Accordingly, it is an object of the present invention to provide a rubber contact switch that does not require a push pin and a guide portion, is easy to mold, reduces the number of parts, and improves the assemblability.

[0013]

In order to achieve the above object, the invention as set forth in claim 1 is a rubber contact switch having a rubber contact integrally formed with a rubber sheet provided on a wiring board. In the rubber contact, a central push button portion and the rubber sheet are connected via a connecting portion, and the connecting portion includes an upper surface portion, a lower surface portion parallel to the upper surface portion and having the same length, and the upper surface portion. It is characterized in that it is formed in a concavo-convex shape composed of vertical wall portions connected to both edges of the lower surface portion.

Therefore, according to the first aspect of the present invention, when the push button portion is pushed down, the push button portion acts as a parallel link which deforms while maintaining the parallel state between the upper surface portion and the lower surface portion, and the vertical wall portion has the push button. It acts to resist the force of the tilting direction of the part, and the push button part is always forced to move in a vertical linear motion.

A second aspect of the present invention is the rubber contact switch according to the first aspect, wherein the vertical wall portion is formed thinner than the upper surface portion and the lower surface portion.

Therefore, according to the second aspect of the invention, the vertical wall portion flexibly follows the depression while acting to resist the force in the tilting direction of the push button portion.

The invention according to claim 3 is the invention according to claim 1 or 2.
A rubber contact switch according to claim 1, wherein a tapered surface is formed on a key top that is swingably attached to the switch case, and the push button portion is directly pressed by the swing operation of the key top. It is characterized by having done.

Therefore, in the invention according to claim 3, the push button portion is pressed by the tapered surface by the swing operation of the key top. Even if the force applied from the tapered surface to the push button portion is not in the completely vertical direction, the push button portion performs a vertical linear motion, so that a push pin and a guide portion are unnecessary.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings. The same members and functions as those in FIGS. 5 and 6 are designated by the same reference numerals.

1 and 2, a rubber contact 3 is integrally formed on a rubber sheet 2 mounted on a wiring board 1. The rubber contact 3 is formed by integrally connecting an inner peripheral surface 4a of a circular hole 4 formed in the rubber sheet 2 and a central cylindrical push button portion 5 at a connecting portion 6, and is formed on the wiring board 1. The fixed contact 10 and the movable contact 11 are attached to the lower surface of the push button portion 5 to form a rubber contact switch A.

The connecting portion 6 is an upper surface portion 7 which is connected to the outer peripheral surface 5a of the push button portion 5 from the upper end edge of the inner peripheral surface 4a of the circular hole 4.
And a lower surface portion 8 connected to the push button portion 5 from the inner peripheral surface 4a of the circular hole 4, and a vertical wall portion 9 connected between the upper surface portion 7 and the lower surface portion 8 to form an uneven shape. ing. Top part 7
And the lower surface portion 8 are parallel to each other and are formed to have the same length.

By constructing the connecting portion 6 in this way, as shown in FIG. 2, the upper surface portion 7 and the lower surface portion 8 are parallel to each other, and the outer peripheral surface 5a of the push button portion 5 and the rubber sheet 2 are formed. A parallelogram is formed which is parallel to the inner peripheral surface 4a.

When the push button portion 5 is depressed, the upper surface portion 7 and the lower surface portion 8 are bent and deformed downward, as shown in FIG.
At the same time, the vertical wall portion 9 is curved and deformed so as to bulge outward and follows the movement of the push button portion 5 (the deformation direction is indicated by an arrow in the figure). In this way, the stress of the entire portion of the connecting portion 6 is concentrated on the peripheral portion of the push button portion 5, and the push button portion 5 is acted upon by the restoring force to restore the original shape. Therefore, when the depression of the push button portion 5 is released, the original state is promptly restored.

When the push button portion 5 is depressed, even if the upper surface portion 7 and the lower surface portion 8 are curved, the parallel state between them is maintained as shown by the chain line in FIG. 2, and the outer peripheral surface 5a of the push button portion 5 is maintained. The inner peripheral surface 4a of the rubber sheet 2 is also kept parallel.
That is, when the push button portion 5 is actuated, the upper surface portion 7 and the lower surface portion 8 function as a parallel link with the four corners a, b, c, d of the parallelogram as fulcrums. Further, since the vertical wall portion 9 has a large resistance to vertical deformation,
It has a function of supporting the push button portion 5 from the surroundings, and the force for vertically holding the push button portion 5 is further strengthened.

As described above, since the push button portion 5 is always forced to move linearly, the push button portion 5 always moves in the vertical direction even if the force applied to the push button portion 4 is not a completely vertical force. Is to do.

In the above embodiment, the upper surface portion 7 and the lower surface portion 8 are formed as flat surfaces, but they may be curved in a dome shape as long as they are kept in parallel. Further, since the vertical wall portion 9 has a large resistance against pressing of the push button portion 5, the vertical wall portion 9 may be formed thinner than the upper surface portion 7 and the lower surface portion 8. By doing so, the vertical wall portion 9 can flexibly follow the depression while acting to resist the force of the push button portion 5 in the inclination direction.

FIG. 4 shows an example in which the rubber contact switch A of the above embodiment is applied to a keytop type switch device.

In FIG. 4, the rubber contact switch A of this embodiment is mounted on the wiring board 1. Above the rubber contact switch A, a key top 15 is provided which is swingably supported by the switch case 13 via a shaft 14.

Convex tapered surfaces 16a and 16b are formed on the lower surface of the key top 15, and the tapered surfaces 16a and 16b are formed.
b is located above the push button portion 5. The LED 17 connected to the wiring board 1 illuminates the illumination section 18 on the upper surface of the key top 15.

When the key top 15 is swung in the clockwise direction in FIG. 4, the right push button portion 5 is pushed by the tapered surface 16a to switch on, and when swung in the counter clockwise direction, the left push button portion 5 is pushed. Is pressed by the tapered surface 16b to switch on.

In this case, since the pressing directions of the tapered surfaces 16a and 16b are not completely vertical, a push pin and a guide portion have been indispensable in the past, but in the rubber contact switch A of this embodiment, the push button portion is required. Since 5 has a function of forced linear movement, the key top 15 can be directly pressed.

As described in detail above, in the rubber contact switch A of this embodiment, the upper surface portion 7 and the lower surface portion 8 function as parallel links, and the vertical wall portion 9 supports the push button portion 5 from the surroundings. Since the push button portion 5 has a function, the push button portion 5 is always forced to move linearly, and the push button portion 5 always moves in the vertical direction linear movement even if the force applied to the push button portion 4 is not a perfect vertical force. The switch can be reliably turned on and off, and the reliability of the switch is improved. Further, the rubber contact 3 can be formed of the same resin material as the rubber sheet 2 and is easily molded.

Therefore, for example, when used in a switch device operated by the key top 15, the push button portion 5 can be directly pressed by the tapered surfaces 15a and 15b of the key top 15,
The push pins and guides that were previously indispensable are no longer required,
The number of parts can be reduced and the configuration and assembly can be simplified.

[0034]

As described above in detail, according to the first aspect of the present invention, the upper surface portion and the lower surface portion function as parallel links, and the vertical wall portion supports the push button portion from the surroundings. Therefore, the push button part is always forced to perform a linear motion, and even if the force applied to the push button part is not a complete vertical force, the push button part can always perform a vertical linear motion. The switch can be reliably turned on and off, and the reliability of the switch can be improved. Moreover, since the rubber contact can be formed of the same resin material as the rubber sheet, a rubber contact switch that can be easily molded can be provided.

According to the second aspect of the invention, since the vertical wall portion is formed thinner than the upper surface portion and the lower surface portion,
While the vertical wall portion acts to resist the force in the tilt direction of the push button portion, the vertical wall portion flexibly follows the depression, and a light operation can be performed by linear movement.

According to the third aspect of the present invention, since the push button portion is directly pressed by the tapered surface by the swinging operation of the key top, the push pin and the guide portion are not required, and the number of parts is reduced. The cost can be reduced by simplifying the structure and assembly.

[Brief description of drawings]

FIG. 1 is a perspective view of a rubber contact according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional side view of a main part of a rubber contact switch according to an embodiment of the present invention.

FIG. 3 is an operation explanatory view of the rubber contact portion of FIG. 1 when the push button portion is pressed.

FIG. 4 is a vertical sectional side view showing an embodiment applied to a keytop type switch.

FIG. 5 is a vertical cross-sectional side view showing a key top type rubber contact switch of a first conventional example.

FIG. 6 is a vertical sectional side view showing a rubber contact switch of a second conventional example.

[Explanation of symbols]

 1 wiring board 2 rubber sheet 3 rubber contact 5 push button part 6 connecting part 7 upper surface part 8 lower surface part 9 vertical wall part 15 key top 15a, 15b taper surface A rubber contact switch

Claims (3)

[Claims] 1. A rubber contact switch having a rubber contact integrally formed with a rubber sheet provided on a wiring board, wherein the rubber contact has a central push button portion and the rubber sheet via a connecting portion. And the connecting portion is formed in an uneven shape including an upper surface portion, a lower surface portion that is parallel to the upper surface portion and has the same length, and vertical wall portions that are connected to both end edges of the upper surface portion and the lower surface portion. A rubber contact switch characterized by being used. 2. The rubber contact switch according to claim 1, wherein the vertical wall portion is formed thinner than the upper surface portion and the lower surface portion. 3. A key top that is swingably attached to a switch case is formed with a taper surface, and the rocking operation of the key top directly presses the push button portion. The rubber contact switch according to claim 1 or 2.