GB2037079A

GB2037079A - Modular keyboard

Info

Publication number: GB2037079A
Application number: GB7847163A
Authority: GB
Original assignee: Standard Telephone and Cables PLC
Current assignee: STC PLC
Priority date: 1978-12-05
Filing date: 1978-12-05
Publication date: 1980-07-02

Abstract

A modular keyboard construction has individual electrical contact units 6 located in apertures 5 in a spacer sheet 2 forming part of a laminate structure and has a flexible covering sheet 4 with indicia above individual compliants operating means 7. The contact units 6 are electrically connected through a printed circuit substrate 1. <IMAGE>

Description

SPECIFICATION Modular keyboard This invention relates to modular keyboards and method of fabricating such keyboards.

There is a growing requirement for keyboard controlled equipment as electronic devices find wider applications. For many applications the keyboard requirements are different, e.g. the number and/or spacing of the keyboard elements. The present invention seeks to provide flexibility in the manufacture of keyboards whereby different requirements can be readily met using a number of standard components. The invention is particularly useful where only limited quantities of a given keyboard configuration are required.

According to the invention a modular keyboard comprises a substrate board having on one face thereof a number of printed circuit contact patterns one for each of a corresponding number of switch elements, a spacer sheet adjacent the other face of the board, the spacer sheet having apertures therethrough corresponding in number and position to the contact patterns, a number of individual pressure operated electric switch contact units one in which each aperture, each contact unit being electrically connected through the board to the corresponding contact pattern, and a flexible sheet covering the spacer sheet and the contact units, the flexible sheet having means whereby the position of each contact unit beneath the flexible sheet is indicated so that pressure applied to an indicated position on the flexible sheet causes the corresponding contact unit to be operated.

In a preferred embodiment the spacer sheet is of a thickness such that the flexible sheet is spaced from the operating surfaces of the contact units and each unit is provided with an individual compliant operating means between the operating surface of the unit and the flexible sheet.

Embodiments of the invention will now be described with reference to the accompanying drawings, in which: Figures 1A and 18 show a cross-section through and an exploded view respectively of one construction of a modular keyboard, Figures 2A and 2B show a cross-section through and an exploded view respectively of an alternative construction of a modular keyboard, and Figure 3 illustrates a detail of the flexible sheet of Figs. 2A and 2B.

Referring to Figs. 1 A and 1 B, a substrate 1 has a printed circuit connection pattern (not shown) formed on its underside. The upper side of the substrate is overlaid with a first spacer sheet 2, a second spacer sheet 3 and a flexible foil cover sheet 4. The first spacer sheet 2 is provided with an array of apertures 5 the number and layout of which are determined by the requirements of the keyboard.

In each aperture 5 there is located an individual pressure operated electric switch contact unit 6. One form of a suitable contact unit is that disclosed in British patent specification No. 1,361,459 (T.M. Jackson-R.P.

Gearing-R.J. Hodges-47-20- 1). Such a unit is provided with wire terminal leads which can be connected through holes in the substrate 1 to the printed circuit patterns on the underside of the substrate. Each unit 6 is provided with an individual compliant operating member 7 located within the same spacer aperture 5. The second spacer sheet 3 has an array of apertures 8 corresponding to the array in the first spacer sheet, but the apertures 8 are somewhat smaller in diameter than the apertures 5 and provide a means of securing the circular compliant members 7.

The foil cover sheet 4 has printed on its upper surface legend characters 9 in positions corresponding to the contact unit positions. The substrate 1, spacer sheets 2 and 3, and the foil cover sheet 4 are all bonded into a laminated structure with adhesive.

In the arrangement shown in Figs. 2A and 2B the substrate 1 and first sheet 2 are as before, with contact units 6 disposed in the apertures 5. There is no second spacer sheet and the cover sheet is replaced by a semi-rigid sheet 10 with an array of operating members 11 formed therein. Each operating member 11 comprises a central portion 1 2 connected to the surrounding sheet material by a set of arcuate limbs 1 3 defined by slots 1 4 to provide a well known form of diaphragm spring. The central portion 1 2 has a hole 1 5 which locates a compliant member 1 6 placed between the central portion 1 2 and the contact unit 6.The semi-rigid sheet 10 may be covered by a protective film 1 7 bearing printed legends for the contact units. As in the previous case, the various sheets are laminated with adhesives. The materials which can be used for various components are not critical. The substrate can be a conventional printed circuit, e.g. on a phenolic resin bonded paper board. The spacer sheet or sheets can be either PVC or polypropylene.

The semi-rigid sheet of Fig. 3 can be either phosphor-bronze or nylon or polypropylene.

The compliant members 7 in Figs. 1 A and 1 B can be any resilient plastics material, e.g.

polypropylene. The flexible cover sheet in Figs. 1 A and 1 B can be a thin film plastics material such as that sold under the trade mark MAKROLON.

CLAIMS (5 Dec 1978) 1. A modular keyboard comprises a substrate board having on one face thereof a number of printed circuit contact patterns one for each of a corresponding number of switch elements, a spacer sheet adjacent the other face of the board, the spacer sheet having apertures therethrough corresponding in number and position to the contact patterns, a number of individual pressure operated electric switch contact units one in each aperture, each contact unit being electrically connected through the board to the corresponding contact pattern, and a flexible sheet covering the spacer sheet and the contact units, the flexible sheet having means whereby the position of each contact unit beneath the flexible sheet is indicated so that pressure applied to an indicated position on the flexible sheet causes the corresponding contact unit to be opelrated.

2. A keyboard according to claim 1 in which the spacer sheet is of a thickness such that the flexible sheet is spaced from the operating surfaces of the contact units and each unit is provided with an individual compliant operating means between the operating surface of the unit and the flexible sheet.

3. A keyboard according to claim 2 wherein the flexible sheet is formed with individual diaphragm spring means for each contact unit, the compliant operating means serving to transmit movement of the spring means to the contact unit.

4. A keyboard according to claim 2 including a second spacer sheet interposed between the first spacer sheet and the flexible sheet, the second spacer sheet having apertures correspond in position to and of lesser diameter than the apertures in the first spacer sheet, the compliant operating members being of the same planar dimensions as the contact units, the thickness of the first spacer sheet being such that the compliant members are secured in the apertures of the first spacer sheet adjacent the contact units.

5. A keyboard according to any preceding claim in which the substrate, spacer sheet or sheets and flexible sheet are laminated together with adhesives.

6. A keyboard according to any preceding claim in which the flexible sheet is covered with a protective film bearing printed legends.

7. A modulator keyboard substantially as described with reference to Figs. 1 A and 1 B or Figs. 2A and 2B of the accompanying drawings.

8. A method of making a modulator keyboard substantially as described with reference to Figs. 1 A and 1 B or Figs. 2A and 2B of the accompanying drawings.

CLAIMS (17 May 1979) 1. A modular keyboard comprising a substrate board having on one face thereof a number of printed circuit contact patterns one for each of a corresponding number of switch elements, a spacer sheet adjacent the other face of the board, the spacer sheet having apertures therethrough corresponding in number and position to the contact patterns, a number of individual hermetically sealed pressure operated electric switch contact units one in each aperture, each contact unit being provided with wire terminal leads electrically connected through the board to the corresponding contact pattern, and a flexible sheet covering the spacer sheet and the contact units, the flexible sheet having means whereby the position of each contact unit beneath the flexible sheet is indicated so that pressure applied to an indicated position on the flexuble sheet causes the corresponding contact unit to be operated.

7. A modular keyboard substantially as described with reference to Figs. 1A and 1 B or Figs. 2A and 2B of the accompanying drawings.

8. A method of making a modular keyboard substantially as described with reference to Figs. 1A and 1B or Figs. 2A and 2B of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

apertures therethrough corresponding in number and position to the contact patterns, a number of individual pressure operated electric switch contact units one in each aperture, each contact unit being electrically connected through the board to the corresponding contact pattern, and a flexible sheet covering the spacer sheet and the contact units, the flexible sheet having means whereby the position of each contact unit beneath the flexible sheet is indicated so that pressure applied to an indicated position on the flexible sheet causes the corresponding contact unit to be opelrated.
2. A keyboard according to claim 1 in which the spacer sheet is of a thickness such that the flexible sheet is spaced from the operating surfaces of the contact units and each unit is provided with an individual compliant operating means between the operating surface of the unit and the flexible sheet.
3. A keyboard according to claim 2 wherein the flexible sheet is formed with individual diaphragm spring means for each contact unit, the compliant operating means serving to transmit movement of the spring means to the contact unit.
4. A keyboard according to claim 2 including a second spacer sheet interposed between the first spacer sheet and the flexible sheet, the second spacer sheet having apertures correspond in position to and of lesser diameter than the apertures in the first spacer sheet, the compliant operating members being of the same planar dimensions as the contact units, the thickness of the first spacer sheet being such that the compliant members are secured in the apertures of the first spacer sheet adjacent the contact units.
5. A keyboard according to any preceding claim in which the substrate, spacer sheet or sheets and flexible sheet are laminated together with adhesives.
6. A keyboard according to any preceding claim in which the flexible sheet is covered with a protective film bearing printed legends.
7. A modulator keyboard substantially as described with reference to Figs. 1 A and 1 B or Figs. 2A and 2B of the accompanying drawings.
8. A method of making a modular keyboard substantially as described with reference to Figs. 1A and 1B or Figs. 2A and 2B of the accompanying drawings.

8. A method of making a modulator keyboard substantially as described with reference to Figs. 1 A and 1 B or Figs. 2A and 2B of the accompanying drawings.

CLAIMS (17 May 1979)

1. A modular keyboard comprising a substrate board having on one face thereof a number of printed circuit contact patterns one for each of a corresponding number of switch elements, a spacer sheet adjacent the other face of the board, the spacer sheet having apertures therethrough corresponding in number and position to the contact patterns, a number of individual hermetically sealed pressure operated electric switch contact units one in each aperture, each contact unit being provided with wire terminal leads electrically connected through the board to the corresponding contact pattern, and a flexible sheet covering the spacer sheet and the contact units, the flexible sheet having means whereby the position of each contact unit beneath the flexible sheet is indicated so that pressure applied to an indicated position on the flexuble sheet causes the corresponding contact unit to be operated.

7. A modular keyboard substantially as described with reference to Figs. 1A and 1 B or Figs. 2A and 2B of the accompanying drawings.