JPS59203321A - Flat panel switch - 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 a flat panel switch that can configure a large number of contacts on a single switch board by combining two directional pressure-sensitive conductive sheets. be.

In recent years, there has been a remarkable wave of electronics using microcomputers (hereinafter referred to as microcomputers), from small things such as calculators, toys, and home appliances to various industrial measurement and control equipment, airplanes, All sorts of things, even large ones such as cars, are being made into electronics.

Keyboard switches for input play an important role as input devices for these microcomputer-applied devices, and among these, one type that has been rapidly attracting attention recently is a type called a flat panel switch1, in which the keys are placed on the panel. It's a keyboard switch that doesn't stick out.

There are two types of flat panel switches: non-contact type and contact type. The non-contact type uses a switch without mechanical contacts, and has the advantage of no mechanical deterioration and high reliability, but has the disadvantage of high cost. There are many different types of contact type switches, but the one that has been attracting particular attention recently is the flat panel switch called a membrane switch.

FIG. 1 is a sectional view showing the structure of the conventional membrane switch. In this membrane isochi, two flexible surface films 1 each having a circuit pattern formed of a conductor are placed opposite to each other with a spacer 2 in between, and a through hole 6 is provided in the spacer 2 at the opposite portion of the circuit to form a contact point 4. The film 1 on the front side is pushed in the direction of arrow P to bring both contacts 4 into electrical continuity.

However, such membrane switches consist of contacts corresponding to the number of switches and spacers with holes drilled only in the contact areas to maintain insulation when no pressure is applied, so the number of switches can be adjusted depending on the purpose. It could not be increased or decreased.

This is a drawback that also applies to other conventional flat panel switches.

It is an object of the present invention to eliminate the disadvantages of the conventional flat switch in that once the circuit pattern, number of contacts, and contact positions cannot be changed again, and the labor required for assembly, and to achieve high mounting density of the switch. A control device that allows you to specify the number of switches as desired.

To provide a flat panel switch that can be used as an input keyboard switch for calculators, microcomputers, etc.

In order to achieve the above object, the present invention uses two pressure-sensitive conductive sheets, which are integrally constructed with an insulating base sheet, a conductive material, and an insulating protrusion, and which provide directionality for conduction, and are made by intersecting each other. A flat panel switch is constructed by overlapping the conductive materials and using the overlapping portions of the conductive materials as contacts.

The present invention will be described in detail below using the drawings.

FIG. 2 is an assembled perspective view showing the structure of one embodiment of the flat panel switch 10 of the present invention.

In this invention, a strip-shaped conductive U1 is provided on the base sheet 11.
2 are stacked with a predetermined gap between them, and a barrier 16, which is a protruding strip, is integrally attached to the three members in such a way that the top of the barrier 16 protrudes above the surface of the conductive control 2. The pressure-sensitive conductive sheet 14 is constructed as a whole. Then, two pressure-sensitive conductive sheets 14 configured in this manner are stacked one on top of the other so that the conductive materials 12 cross each other to form a flat panel switch 10. In the embodiment shown in Fig. 2, the crossing angle is 90°;
It is not limited to this, and various angles can be set depending on the place of use.

The base notebook 11 is preferably a flexible elastic material having good physical properties and electrical insulation properties, and polyester elastomer, urethane, etc. are particularly suitable.

The conductive strip 12 is preferably of low resistance, and is laminated on the base 7-11 by pasting aluminum, copper, or the like in a striped manner and applying it to provide directionality of conduction. Further, as the material for the barrier 16, a resin of the same type as the base sheet 11 is suitable since it requires adhesiveness with the base sheet 11, repeated compression, and durability.

FIG. 3 is a partial vertical sectional view of the flat panel switch assembled as shown in FIG. 2, and FIG. 4 is an explanatory diagram of the distribution of conductors seen from above. As shown in these figures, in this embodiment the 90'' intersecting conductive material 12 is typically separated by a barrier 16.

In the flat panel switch 10 configured as described above, if there are m circuits formed by the conductive material 12 in the X coordinate direction and n circuits in the Y coordinate direction as shown in FIG. Maximum mXn for switch 10
Contact points are obtained, and which contact point is turned on can be known by the combination of the terminal in the X coordinate direction and the terminal in the Y coordinate direction. For example, when switch Q located at the coordinates (XK, YL) in Figure 6 is pressed, terminal XK and terminal YL become electrically connected.If this is detected by the electric circuit connected to each terminal, switch Q The position of can be detected.

FIG. 5 shows the state in which the switch Q (XK, YL) is turned on using the press rod 15, and the conductive material 12 is pressed by the elastic force of the base sheet 11.
The only part is bent and comes into contact with the conductive control 2 that intersects with this, and is electrically conductive. At this time, since the other contacts are floating by the barrier 16, the contacts at locations other than the pressure points will not become conductive. Therefore, a maximum of mXn contacts can be obtained by one fland panel switch.

Methods for detecting each contact point include a method of digitally extracting each contact point of the flat panel switch 10 directly as data as shown in FIG. A possible method is to short-circuit the terminals with resistors 16 and 17 and extract each contact position as a voltage value in an analog manner.

In the case of FIG. 7, the soft register 18 is for sending pulses from the pulse generator 23 to each X terminal in order to distinguish the X coordinate from the X coordinate side.In principle, this shift register 18 However, in order to reduce the number of bits of other data, a data encoder 19 and an OR circuit 20 for controlling it are provided in this embodiment. It is also possible to attach a latch or the like as necessary. This method is suitable when the number of contacts is small or when high accuracy is required.

In the method shown in FIG. 8, the X-coordinate side and the X-coordinate side are short-circuited with resistors 16 and 17, respectively, as described above, and a potentiometer is configured to detect the pressed position. In this case, since the X coordinate and the . This method is suitable when the number of contacts is large. With such a circuit, the position of the ON contact of the Q72 top panel switch can be reliably detected.

As explained above, the flat panel switch of the present invention is composed of a combination of pressure-sensitive unidirectional conductive sheets with fine patterns, so it has a much larger number of switches than conventional flat panel switches. This makes it possible to implement the present invention, and as a result, the present invention has the effect of being able to sufficiently support input devices that require high resolution and precision, such as writing input devices. Furthermore, when used in a writing device, there is an advantage that erroneous inputs due to manual touch, which was a problem with conventional flat panel switches, hardly occur because the barrier is minute.

[Brief explanation of drawings]

Fig. 1 is a partial longitudinal sectional view showing the structure of a conventional membrane switch, Fig. 2 is an assembled one-sheet view showing the structure of an embodiment of the flat panel switch of the present invention, and Fig. 3 is a flat panel switch of the present invention. A partial vertical cross-sectional view of a panel switch. Fig. 4 is an explanatory diagram showing the distribution of conductive material in a flat panel switch when the intersection angle is 90°. Fig. 5 is an enlarged view of the main part showing the operation of the flat panel switch of the present invention. A perspective view, FIG. 6 is a circuit configuration diagram of a flat panel switch of the present invention, and FIGS. 7 and 8 are circuits showing an embodiment of an electric circuit for detecting the pressed position of the flat panel switch of the present invention. FIG. DESCRIPTION OF SYMBOLS 10... Flat panel switch, 11... Base note, 12... Conductive phase, 13... Barrier, 14...
...Pressure-sensitive conductive sort, 15...Press rod, 16, 1
7...Resistor, 18...Soft resistor, 19...
- Data encoder, 21... changeover switch circuit. Agent Patent Attorney Makoto Ogawa - Patent Attorney Ken Noguchi Teru Patent Attorney Kazuhiko Sai Figure 1 Figure 3 @ 'IK4 Figure k Figure 5 xl X2 X3 X4 XK Xm-]Xm No. 6
Fig. 10 Fig. 8

Claims (1)

[Claims] A unidirectionally conductive conductive material is laminated on a flexible non-conductive base sheet, and non-conductive protrusions that are also flexible are laminated from the surface of the conductive material in the same direction as the conductive direction of the conductive material. Two pressure-sensitive conductive sheets each having a plurality of protruding strips are placed one on top of the other in opposing contact so that the protrusions are not parallel, and the intersecting opposing portions of the pressure-sensitive conductive sheets are used as contact points. A flat panel switch featuring