Patent ID: 6027267
Filing Date: 2000-02-22
Classification: H01H

Abstract:
A keyboard comprising:a rectangular housing made of rigid synthetic resin having width dimensions greater than depth dimensions, said housing having a plurality of quadrilateral openings formed therethrough and arrayed at intervals both in the width direction and in the depth direction so as to define widthwise delimiting regions between each widthwise adjacent openings, each of said widthwise delimiting regions having notches cut in from two opposed side edges of the widthwise adjacent openings, said notches being staggered depthwise from each other;quadrilateral key tops, each disposed within one of said openings and formed integrally with said housing by means of at least two hinges extending from one side edge of the key top parallel to the width direction, each of said key tops having engagement tabs extending oppositely outward from two opposed side edges thereof adjoining said side edge where said hinges are formed, said engagement tabs entering into said notches formed in the opposed corresponding side edges of said openings;an elastic rubber sheet attached to the undersurface of said housing and having upwardly convex raised portions embossed thereon in correspondence to the corresponding key tops;a movable-contact sheet having movable contacts formed on the undersurface thereof in correspondence to the corresponding key tops;a fixed contact sheet having fixed contacts formed thereon in spaced opposed relation to the corresponding movable contacts;a separator interposed between said movable-contact sheet and said fixed-contact sheet and having apertures formed therethrough to define void spaces surrounding the corresponding opposed movable contacts and fixed contacts, said movable-contact sheet, said fixed-contact sheet, and said separator together constitute a membrane switch attached to the undersurface of said rubber sheet; anda face panel attached to the upper surface of said housing and having key top openings formed therethrough and arrayed at intervals both in the width direction and in the depth direction, said key top openings having the corresponding key tops protrude upwardly therethrough.