JPH1167005A - Seat switch - Google Patents

Abstract

(57) [Problem] To provide a sheet switch that has a long life, high reliability, and can increase a contact capacity. SOLUTION: The sheet switch 1 is formed by bonding a sheet 2 having a first metal contact 2a and a rubber switch 3 having a second metal contact 3a with a double-sided tape 4. The rubber switch 3 includes a base 3b, a key top 3c, a spring 3d, and the like.
The second contact 3a is located in the first direction in the thickness direction of the sheet 2.
And at a distance from the contact 2a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet switch, and more particularly to a sheet switch used for detecting a surface load by an elastic body.

[0002]

2. Description of the Related Art A membrane switch is conventionally used as a seat switch for detecting a surface load by an elastic body such as a seating sensor.
FIG. 3 shows an example of this membrane switch. This membrane switch has a membrane sheet 5 in which wiring and the like are formed on a base material such as a PET film by a printing pattern using a conductive paste. Then, the membrane sheet 5 is folded, the gap formed inside the folded sheet is provided with a spacer 6 for insulation, and the spacer 6 and the membrane sheet 5 are bonded together by the double-sided tapes 7, 7 '. Here, a gap is formed at a substantially central portion of the spacer 6, and a PET sheet is formed on the inner surface of the membrane sheet 5 located in the gap.
An upper contact 5a and a lower contact 5b made of a plastic material such as the above are formed.

[0003] In the membrane switch having the above configuration,
When a surface load is applied to the entire surface of the membrane sheet 5 by the elastic body, the membrane sheet 5 at the space of the spacer 6 is bent. Then, as a result, the upper contact 5a and the lower contact 5b of the membrane sheet 5 come into contact with each other and become conductive. Thereby, the membrane switch is turned on from off. Further, by eliminating the surface load due to the elastic body, the membrane sheet 5 returns to its original shape due to its elasticity. At this time, the upper contact 5a and the lower contact 5
b is separated. Thereby, the membrane switch is turned off from on.

[0004]

However, in the case of the above-mentioned membrane switch, since the upper and lower contacts are made of a plastic material, the switch is repeatedly used, used at a high temperature, or when the switch is on for a long time. When used, the switch may be damaged or damaged, and the switch operation is likely to be unstable due to the damage or damage. For this reason, there is a problem in life and reliability.

In addition, since the wiring formed on the PET film has the above-described printed pattern, the electric resistance of the wiring is increased, and the contact capacity is limited to a small value, thereby increasing the allowable current of the wiring. It becomes difficult.
For this reason, for example, it was not possible to provide additional value on the circuit due to the problem of the current value, such as causing the LEDs connected to the wiring to emit light in conjunction with each other when the switch is on.

That is, the conventional membrane switch has problems in contact capacity (allowable current value), life, and reliability.

It is an object of the present invention to provide a seat switch having a long life, high reliability, and capable of increasing a contact capacity (allowable current value).

[0008]

A sheet switch according to the present invention comprises a sheet having a first contact made of metal on one surface, and a sheet switch in a thickness direction of the sheet in a normal state, that is, when a load is not applied. A second switch made of metal opposed to the first contact at a distance, and a rubber switch disposed on one surface of the sheet.

[0009] The sheet is preferably made of FPC. Further, preferably, the rubber switch, a substantially frame-shaped base portion fixed on one surface of the sheet, and a key top portion provided with the second contact point, disposed inside the base portion, A spring portion that connects the base portion and the key top portion and elastically supports the key top portion;

Further, in a preferred example, the surface of the key top portion to which the load is applied and the surface of the base portion to which the load is applied are flush with each other, and the spring portion reduces the load of the key top portion. It does not protrude from the surface to which it is applied.

In another preferred embodiment, the surface of the key top portion to which the load is applied is lower than the surface of the base portion to which the load is applied, and the spring portion is a surface to which the load of the key top portion is applied. It does not protrude from.

[0012]

Embodiments of the present invention will be described below. FIG. 1 shows a seat switch 1 according to an embodiment of the present invention. The sheet switch 1 includes a sheet 2, a rubber switch 3, and a double-sided tape 4.

The sheet 2 is made of, for example, FPC (Flexible P
rinted circuit). And
The sheet 2 has a metal first contact 2a on one surface, that is, on the upper surface in FIG.

The rubber switch 3 is made of an elastic rubber such as silicon rubber. And sheet 2
, That is, on the upper surface in FIG. The rubber switch 3 has a metal second contact 3a, a base 3b, a key top 3c, and a spring 3d. And the base part 3b, the key top part 3c, and the spring part 3d are integrally formed.

The first contact 2a and the second contact 3a are formed by gold plating or the like. The second contact 3a is located in the first contact 2a in the thickness direction of the sheet 2.
And at intervals. Also, the base part 3b
It is substantially frame-shaped and fixed on one surface of the sheet 2. The key top portion 3c is disposed inside the base portion 3b so as to be movable in the vertical direction, and has a second contact 3a provided on the lower surface thereof. Furthermore, the spring part 3d
Connects the base portion 3b and the key top portion 3c, and elastically supports the key top portion 3c.

Further, in the illustrated example, the key top portion 3
c, ie, the upper surface of the key top portion 3c and the surface of the base portion 3b to which the load is applied,
That is, the upper surface of the base portion 3b in FIG. 1B is flush, that is, aligned on the same plane. Therefore, the spring portion 3d does not protrude from the surface of the key top portion 3c to which the load is applied.

As another configuration example, the surface of the key top portion 3c to which the load is applied may be lower in FIG. 1B than the surface of the base portion 3b to which the load is applied. Also in this case, the spring portion 3d does not protrude from the surface of the key top portion 3c to which the load is applied, similarly to the above.

The double-sided tape 4 is sandwiched between the base 3d of the rubber switch 3 and the sheet 2, whereby the peripheral portion of the rubber switch 3 is adhered and fixed on the sheet 2.

In the seat switch 1 of the present embodiment having the above configuration, as shown in FIG. 2, when a surface load is applied from the upper surface of the rubber switch to the entire surface thereof, the key top portion 3b of the rubber switch 3 has a load. , That is, downward, and elastically deform. As a result, the second contact 3a on the lower surface of the key top portion 3b comes into contact with the first contact 2a of the sheet 2, and the switch is turned on. The switch is turned off by eliminating the surface load, moving the key top portion 3b upward by the elasticity of the spring portion 3d, and separating the first contact 2a and the second contact 3a. Done.

Here, the spring portion 3d of the rubber switch 3 is provided within the thickness of the base portion 3b, and the rubber switch 3 itself can be used as a flat sheet switch. For this reason, the seat switch 1 of the present embodiment
It can be used for applications such as a seating sensor for detecting the presence or absence of a person on a seat, or a flat panel of a topsheet type.

The movable portion for performing the switching operation is the spring portion 3d, and since the spring portion 3d is formed of the same material as the rubber switch 3, it can be used repeatedly, used under high temperature, Alternatively, the life and reliability after long switch-on or the like are high.

Further, the first contact 2a and the second contact 3a
Is made of metal such as gold plating, so that the contact capacity can be increased. For this reason, it is possible to provide a value added to the circuit, which is difficult in the conventional configuration, for example, a configuration in which the LED connected to the wiring is illuminated in conjunction with the switch being turned on.

[0023]

As described above, the sheet switch of the present invention is constituted by the sheet having the first metal contact and the rubber switch having the second metal contact, and thus has a flat shape. Long life and high reliability can be achieved. In addition, since the first contact and the second contact are made of metal, it is possible to increase the contact capacity and add value to the electric circuit.

[Brief description of the drawings]

FIG. 1A is a plan view of a sheet switch according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA in FIG.

FIG. 2 is an explanatory diagram of an operation of the sheet switch of FIG. 1;

FIG. 3 is an explanatory diagram of a conventional sheet switch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet switch 2 Sheet 2a 1st contact 3 Rubber switch 3a 2nd contact 3b Base part 3c Key top part 3d Spring part 4 Double-sided tape

Claims (5)

[Claims] 1. A sheet having a first contact made of metal on one surface and a second contact made of metal opposed to the first contact in a thickness direction of the sheet in a normal state at a distance. And
And a rubber switch disposed on one surface of the seat. 2. The seat switch according to claim 1, wherein the seat is an FPC. 3. A rubber switch, comprising: a substantially frame-shaped base fixed on one surface of the seat; a key top provided with the second contact and arranged inside the base; Connecting the base part and the key top part,
The seat switch according to claim 1, further comprising a spring portion that elastically supports the key top portion. 4. A surface on which a load of the key top portion is applied,
The surface on which the load of the base portion is applied is flush with the surface, and the spring portion is configured not to protrude from the surface of the key top portion on which the load is applied. Seat switch. 5. The surface of the key top portion to which a load is applied,
The seat switch according to claim 3, wherein the spring portion is located below a surface of the key portion to which the load is applied, and the spring portion does not protrude from a surface of the key top portion to which the load is applied.