JPS6347212B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a keyboard switch, and in particular to a thin keyboard switch, providing a high-density keyboard switch by using an insulating wire for the spacer interposed between the upper and lower electrodes. It is in.

A conventional thin keyboard switch has a flexible insulating sheet with an upper electrode formed thereon and an insulating sheet with a lower electrode formed thereon facing each other, with an insulating spacer interposed between them to prevent the two electrodes from normally touching each other. An insulating film was punched out to match the switch pattern of the upper and lower electrodes.

However, when trying to increase the key density, it is difficult to use thin spacers due to film processing and finishing problems, and the pitch between keys is large, resulting in an area (hereinafter referred to as a dead zone) where input cannot be made on the entire surface of the keyboard switch. The disadvantage was that the keys were large and a high-density key arrangement was not possible.

Therefore, in the present invention, in order to eliminate the above-mentioned drawbacks, an insulating wire is used as a spacer to reduce the dead zone.

The present invention will be described below with reference to the accompanying drawings.
Figure 1 is a plan view of the insulating sheet in contact with the upper electrode;
FIG. 2 is a plan view of the insulating sheet in contact with the lower electrode.

In FIGS. 1 and 2, 1 and 2 are flexible insulating sheets made of synthetic resin, etc.; 1a and 2;
1b and 2b are terminal connecting parts 3;
The projecting portions 3a and 4a are lead portions for connecting the electrodes 3 and 4 to the terminal connecting portions 3b and 4b. The electrodes 3, 4, lead parts 3a, 4a, terminal connection parts 3b, 4b, etc. are formed by etching a copper-clad plastic substrate, silver paste,
It is formed by printing or baking a carbon paste with a low resistivity, or by vapor deposition or sputtering of a transparent conductive thin film of silver oxide, indium oxide, or the like having a low resistivity. Terminal connection part 3
When the diaphragms 1b and 2b are stacked one on top of the other as described later, a predetermined gap is provided between each of the insulating sheets 1 and 2 to prevent electrical problems such as short circuits. Projecting parts 1b, 2
are arranged in parallel on b.

Note that in the present invention, the diaphragms 1a and 2a are provided on a separate pair of insulating sheets 1 and 2, but
A fold line is provided on one continuous insulating sheet, and corresponding electrodes 3, 4, lead parts 3a, 4a, and terminal connecting parts 3b, 4b are formed on the opposite side of the fold line, and later the insulating sheet is attached to the above fold line. More electrodes 3, 4
A pair of diaphragms 1a and 2a may be formed such that the diaphragms 1a and 2a correspond to each other.

FIG. 3 is a plan view of the spacer 5 mounted on the insulating sheet 2. FIG. The spacer 5 is formed by a method described later. On the spacer 5, the insulating sheets 1 in contact with the upper electrode are superimposed, and in this case, the upper and lower electrodes 3 and 4 are stacked on the spacer 5.
do not come into contact with each other due to the spacer 5 under normal conditions.

Figures 4-a and 4-b show the structure of the spacer, and the spacer materials include metal wire coated with insulation such as magnet wire, and insulation with an adhesive layer such as fusible magnet wire. A coated metal wire, a thermoplastic plastic wire, a plastic wire with an adhesive layer, an insulated fiber wire, etc. can be used.

Particularly, Fig. 4-a is a cross-sectional side view of an insulating coated metal wire, and generally the metal wire 6 is coated with an insulating layer 7 of oil-based enamel, polyurethane, polyester, polyimide resin, etc. The spacer 5 is placed between one side of the insulating sheet or between the insulating sheets 1 and 2 and thermocompression bonded by self-heating by energizing metal wires, ultrasonic bonding, high frequency bonding, heat sealing, impulse sealing, etc.

Figure 4-b is a cross-sectional side view of an insulating coated metal wire with an adhesive layer, and nylon, epoxy, polyvinyl butyral, polyvinyl ether, natural rubber, etc. It is coated with an adhesive layer 8 having heat-sensitive adhesive properties or pressure-sensitive adhesive properties, and a spacer is sandwiched between one side of the insulating sheet or between the insulating sheets 1 and 2 by self-heating by energizing a metal wire, heat sealing, impulse sealing, etc. Heat and press. Alternatively, a process of only crimping using a pressure-sensitive adhesive may be used. Furthermore, a thermoplastic wire having heat adhesive properties such as polyethylene soft vinyl chloride polypropylene may be bonded to one side of the insulating sheet or by sandwiching the spacer 5 between the insulating sheets 1 and 2 by the above-described thermal bonding method.

FIG. 5 shows a state in which the keyboard switch according to the present invention is mounted on an insulating substrate, the upper sheet is pressed with a finger, the upper and lower electrodes 3 and 4 are brought into contact, and the switch is turned on.

As detailed above, the keyboard switch of the present invention uses an insulating wire as a spacer between the insulating sheets on which electrodes are formed, so that the pitch between the keys of the keyboard switch does not become large. This has the remarkable effect that the dead zone on the entire surface of the keyboard switch is reduced, making it possible to arrange keys with high density.

[Brief explanation of drawings]

Fig. 1 is a plan view of the insulating sheet in contact with the upper electrode, Fig. 2 is a plan view of the insulating sheet in contact with the lower electrode, and Fig. 3 is an implementation of the present invention, in which a spacer is attached to the insulating sheet. Plan of
4-a and 4-b are cross-sectional side views of an insulating coated metal wire, and FIG. 5 is a cross-sectional view of a keyboard switch according to the present invention mounted on an insulating substrate in operation. 1, 2... Insulating sheet, 3... Upper electrode, 4... Lower electrode, 5... Spacer.

Claims (1)

[Claims] 1. An insulating sheet on which an upper electrode is formed and an insulating sheet on which a lower electrode is formed are arranged so that the upper electrode and the lower electrode face each other, and a plurality of spacers made of wire material having insulating properties are interposed between the two insulating sheets. , a keyboard switch characterized by overlapping both insulation sheets.