JPS61109224A - 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 <Field of Industrial Application> The present invention relates to a keyboard switch applied to cash registers, word processors, communication terminal equipment, and various other office automation equipment, and in particular, the present invention relates to a switch plate.

<Summary of the Invention> A switch in which a membrane sheet is superposed on a printed circuit board via an insulating spacer, in which a conductive film is integrally laminated on the upper surface of the membrane sheet, and a film earth terminal is fixed to the end. . When the switch is attached directly to the bottom of the keyboard, which has a one-piece structure made of synthetic resin molding, the ground terminal is connected to the metal casing to ground static electricity from the key tops to the casing, and the switch circuit and the connection to the circuit are grounded to the casing. Protect electronic components.

<Prior Art> Conventionally, keyboards for keyboard switches include those in which a plunger guide is fitted into a metal frame and a key plunger attached thereto, and the board and plunger guide are integrally formed by molding a synthetic resin material. There is one with a key plunger inserted.

<Problems to be Solved by the Invention> In the keyboard having the metal frame, static electricity from the key tops is grounded to the metal frame and does not cause any trouble to the switch circuit, but in the case where the board and plunger guide are integrated. Static electricity from the key tops may short-circuit the membrane sheet of the switch disposed on the bottom surface of the keyboard or the conductive pattern of the printed circuit board, potentially destroying electronic components.

Means for Solving the Problems> In order to solve the above problems, in the present invention, a conductive pattern constituting a switch is deposited on the bottom surface of a membrane sheet, a conductive film is vapor-deposited on the top surface, and the ends of the conductive film are A film earth terminal was attached to the

According to the above configuration, by connecting the tip of the ground terminal to the metal housing, static electricity from the key top is removed by the conductive film,
Short circuit to the case via the ground terminal to protect the switch circuit and electronic components.

<Embodiment> The drawing shows a keyboard switch, and the keyboard has a plurality of cylindrical plunger guides 2 integrally formed on a substrate 1 by molding a synthetic resin material, as is well known, and a key plunger 3 is moved up and down with respect to each guide 2. A spring 4 is provided in the guide 2 to allow the plunger 3 to return upward and to press the switch. The switch 5 according to the present invention is bonded and arranged on the lower surface of the substrate 1, and the stop shaft 11 protruding from the substrate 1 is made to come out from the stop hole 51 at a suitable position in the switch 5, and its head is caulked and fixed by heating. ing.

The switch 5, which is a feature of the present invention, has an insulating spacer 7,
and a flexible membrane sheet 8 having a conductive pattern 81 paired with the conductive pattern 61 on its lower surface, and a conductive film 82 integrally formed on the upper surface of the membrane sheet 8 by aluminum vapor deposition or the like, The base end of a film earth terminal 83 is fixed to the end of the conductive film 82 by thermocompression bonding or the like, and the tip of the earth terminal 83 is connected to the metal casing 9.

<Effects of the Invention> The present invention is as described above (i.e., an insulating spacer 7 is provided on a printed circuit board 6 having a conductive pattern 61 on its upper surface, and a conductive pattern 81 paired with the conductive pattern 61 is provided on its lower surface). A conductive film 82 is formed on the upper surface of the emblem sheet 8, and a film earth terminal 83 is fixedly attached to the emblem sheet 8.
3 to the casing 9, the key top 31 and the conductive film 82 are brought closest to each other in terms of distance, and therefore static electricity from the key top is grounded to the casing 9 via the conductive film 82 and the terminal 83. switch circuits and electronic components are protected.

However, since the conductive film 82 can be mass-produced by aluminum vapor deposition, it can be obtained at low cost, and since the conductive film 82 has a high resistance value and a low current flow, it has a simple structure and has significant practical effects, such as less noise generation.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a keyboard switch to which the switch of the present invention is applied, and FIG. 2 is a cross-sectional view of the switch of the present invention. 5... Switch 6... Printed circuit board 61
...Conductive pattern 7...Insulating spacer 8.
... Emblem sheet 81 ... Conductive pattern 82
...Conductive film 83...Earth terminal 9...
Case patent source: Tateishi Electric Co., Ltd. Proceeding Officer Voluntary writing> December 19, 1980 2, Title of the invention: Switch 3, Relationship with the person making the amendment case Patent applicant address: 0616 Ukyo-ku, Kyoto City □ Hanazono Tsuchidocho 1o name
(294) Tateishi Electric Co., Ltd. Representative Takao Tateishi 4, Agent ■ 542 No. 21-22 Shimanouchi, Minami-ku, Osaka "Claims of the Specification" 6. Contents of the Amendment Top page of the Claims as per attached sheet In the switch, a flammable membrane sheet having an insulating spacer and a conductive pattern forming a pair with the conductive pattern on the lower surface is placed on a printed circuit board having a conductive pattern on it, and a conductive film is integrated on the upper surface of the membrane sheet. and a film earth terminal is fixed to the end of the conductive film.

Claims (1)

[Claims] In a switch in which an insulating spacer 7 and a flexible membrane sheet 8 having a conductive pattern 81 paired with the conductive pattern 61 on the lower surface are disposed on a printed circuit board 6 having a conductive pattern 61 on the upper surface, the membrane A conductive film 82 is integrally formed on the upper surface of the sheet 8.
A switch consisting of a film earth terminal 83 fixed to the end of 2.