JPS5873923A - Switch device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a flat panel switch device that has recently been used in many fields as an operation panel for various appliances, and in particular, it relates to the structure of a flat panel switch device that has recently been used in many fields as an operation panel for various appliances. It is intended for use in equipment that requires harsh usage conditions such as cooking liquid adhesion, such as grinding cooking equipment.

A typical example of a conventionally used flat panel switch is a touch panel that utilizes the change in capacitance between a person's finger and the conductive pattern on the back of the panel. ■The front panel is formed from a flexible plastic sheet, A pair of flexible printed circuit boards with a printed pattern formed on the back side of the plastic film with a small gap to form a switch contact, or a push switch with a small stroke is provided on the back side of the plastic film. There is a structure in which the flexibility of the surface panel is used to transmit the pressing force to the switch mechanism and close the contact, but the latter plastic sheet panel method is currently more popular due to its simpler structure and lower price. It is widespread. However, both have the following drawbacks, and there are limits to their application to all types of equipment.

In other words, capacitive touch panels are mainly used in microwave ovens and electromagnetic cookers, but in addition to the problem of extremely high cost, they are also susceptible to malfunctions due to cooking liquid or other contamination, malfunctions due to the influence of humidity, and mechanical shock. It has drawbacks such as fragility to thermal shock. Furthermore, plastic sheet type flat panel switches are inexpensive and are mainly used as keyboards for office equipment, computer terminals, etc. However, when used as an operation panel that is exposed to harsh operating conditions such as in cooking equipment, there are fundamental problems arising from the physical properties of the plastic sheet that forms the surface, namely, poor scratch resistance and easy breakage. However, they have the disadvantages of being easily deformed by heat, being chemically affected by detergents used during cleaning, seasonings, etc., and deteriorating.

The present invention aims to solve the above-mentioned conventional drawbacks with a simple structure while maintaining the same operability as the conventional one.In addition to preventing dirt from getting onto the operation panel, it also has heat resistance, chemical resistance, For applications that require mechanical street attack resistance, etc.
It allows the use of rat panel switches,
It can be applied to electric and gas stoves, induction cookers, microwave ovens, open cooking equipment, rotary cookers such as mixers and juicers, and other equipment that is difficult to handle with resin sheet panel switches. It is something.

-The present invention will be explained below with reference to Examples.

FIG. 1 is a side sectional view of one embodiment of the present invention.

In FIG. 1, a spring-elastic metal sheet 1 made of a thin stainless steel plate or the like with a wall thickness of about 0.1 mm has an appropriate diameter so that the surface side of the sheet is convex. , a circular projection 2 with a minute height of around 6 millimeters is provided so as to be freely reversible within its elastic limit,
Close to a position facing the projection 2.

, a push switch 3 having a minute stroke of about 6 millimeters is provided. The entire surface of the metal sheet 1 is fixed to the reinforcing plate 4 by adhesive or other means, so that when the projection 2 is reversed and assumes the shape of 2, the parts other than the projection are not distorted.

When you press the GLOJEXI w72 with your finger 13 as shown in the figure,
2', the bushing switch 3 is pressed and the contact is closed. When the suppression is removed, projection 2' is restored and returns to the shape of 2.

Here, the gap between the projection 2 and the bushing switch 3 is set so that the projection 2 does not completely warp to a stable position, but stops reversing at a position where restoring force remains due to its spring elasticity, and the bushing switch 3 itself When the pressing force is removed, the projection 2 immediately restores its original shape due to the reaction force of the projection 2 and the restoring force of the projection 2 itself.

FIG. 2 shows a conductive rubber contact 7 provided on an operating flexible body 6 made of silicone rubber, etc., and normally open contacts 8 and 9 provided above the printed circuit board 6 with a suitable gap formed between the conductive rubber contact 7 and the conductive rubber contact 7. is closed when the rubber contact 7 moves downward. That is, when the projection 2 provided on the metal sheet 1 is pressed, it is reversed into a 2' shape and the flexible body 6 is pressed, and the rubber contact 7' short-circuits the contact 8' and σ. Then, when the pressing force is removed, the flexible body 6' returns to its original state due to the spring force.
The projection 2' is pushed up and reversed to restore its original state.

FIG. 3 shows a pair of flexible printed circuit boards 11 made by printing a circuit pattern on a resin film such as a polyester film.
and 12 are provided with switch contacts 8 and 9, and by suppressing and inverting the projection 2 provided on a predetermined surface of the metal sheet 1 to form a 2' shape, the switch contacts 8' and 9 are closed. When the pressing force is removed, the projection 2' returns to the polygonal shape 2 due to its own restoring force, and the switch contacts 8 and 9 are opened. Here, 10 is the flexible substrate 1
This is an insulating spacer for providing a predetermined gap between 1 and 12. By using the reversible projection 2 provided on a desired surface of the metal sheet 1 as a touch key in this way, it is possible to provide a design and operability equivalent to that of a conventional resin jet nonel switch.

Moreover, its physical properties are far superior to those of resin sheets.

(1) The surface panel is made of metal sheet, so it is scratch resistant.For example, it will not be damaged even if scratched with a knife or spoon, and even if cooking liquid or coloring agent gets on the horizontally installed panel surface. There is almost no deterioration or damage. Furthermore, it does not change even when exposed to highly heated hot water or oil, and maintains sufficient mechanical strength when combined with a reinforcing plate. Since the physical properties are significantly improved compared to resin sheets, it can be fully used in harsh applications such as operation panels for cooking appliances.

Shun) The projection has a kind of click feeling, so it feels good when you touch it, and you can easily check when it's turned on with the click feeling.

(3) Various types of indications can be printed on the surface of the metal sheet, so there is a high degree of freedom in pattern design.

In addition, the surface metal sheet can be molded, such as ``emboss'' or ``step stamping,'' if necessary, so it is possible to create a three-dimensional structure, for example by adding beads around a flat panel. High degree of freedom in design.

(4) There is a considerable degree of freedom in the height and diameter of the projection, and if it is within the elastic limit of the metal sheet, it can have a reversal stroke of several millimeters, so the switch mechanism has a wide contact spacing that cannot be accommodated with a resin sheet panel. It can also be used for

Therefore, it can be applied to large-capacity switch mechanisms that cannot be handled with resin sheets.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are side cross-sectional views of a switch device according to an embodiment of the present invention, respectively. 1...Metal sheet, 2...Projection, 2...Projection when inverted, 3.
...Button switch, 4...Reinforcement plate,
6... Printed circuit board, 6.6'... Operating flexible body, 7.7'... Conductive rubber contact, 8.
8', 9.9'...°Normally open switch contact, 1o.
... Insulating spacer, 11.12 ... Flexible printed circuit board.

Claims (1)

[Claims] It has a metal sheet having spring elasticity, and a plurality of normally open switch contacts provided close to the back side of the metal sheet, and the metal sheet has a position where each of the normally open switch contacts is normally opposite to each other. A switch device comprising: a projection that can be freely reversed within its elastic limit so that its front side is convex; and the normally open switch contact is closed by a pressing action produced by the reversal of the projection.