GB2122422A - Keyboard switch - Google Patents

Abstract

A keyboard switch has a flexible operating member (11), a switch sheet (13) having portions adapted to undergo a click action, a support (15), a spacer (12) and a plurality of pairs of cooperable contacts (14) on the operating member (11) and switch sheet (13). To facilitate and to ensure operation when a large operating region (17) is employed, the region covers a plurality of contact areas which are wired in parallel. <IMAGE>

Description

SPECIFICATION Keyboard switch This invention relates to a keyboard switch ofthe type having a wide applicability as an operational input switch for various electrical and electronic instruments such as computers or pocket calculators wherein confirmation of input at the time of the switch operation is made possible by virtue of a click action at the time ofthe switch operation.

A proposal forthis type of switch is illustrated in Fig.

1, which is a schematic cross-sectional view of the structure of a keyboard switch arrangement capable of click action. This switch arrangement comprises a flexible operating member 2 having a plurality of contact areas 1 disposed thereon in a desired pattern.

Aflexible switch sheet 6 is provided underneath the operating member 2 and has a corresponding pattern of contact areas 5 placed so as to match the areas 1, being opposed thereto across switch operation spaces 3 provided by use of an insulation spacer 4.

Each contact area 5 is capable of individually carrying outa switch operation in coordination with its corresponding contact area 1,the flexible switch sheet having a shape suitable for initiating click actions. A support member 8 which accommodates the switch sheet 6 is provided with spaces 7 necessary for accommodating click actions by over-centre movement of portions of the sheet 6. At the same time it supports and fixesthe members thereabove including the switch sheet 6. A bonding layer9 e.g. made of a suitable bonding material for the consituent members is provided.

Fig. 2 is a perspective view of part of a keyboard utilising a switching arrangement. Forthe keyboard 10 one wishes to freely choose the size of the operational regions as illustrated bythesmall regionsAto Dand large regions E and F. In the case of particularly large operational regions such as E and F, if structure of the underlying switch arrangement is as shown in Figure 1, suitable switch operation cannot always be accomplished by indiscriminate press operation of the operatoranditisextremelydifficultto build a click operational part as a single unit and let it respond to such a broad operational region in a satisfactory manner.

An object ofthe present invention is to avoid the above problem. Thus, according to the invention there is provided a keyboard switch arrangementcompris- ing a flexible operating member, a switch sheet, a plurality of contact areas provided on the operating member and a plurality of corresponding contact areas provided on the switch sheet, the switch sheet having a plurality of portions, corresponding to the contact areas, which are capable of a click action and there being a plurality of spaces each defined between a corresponding pairofcontact areas, wherein an operating region corresponding to a particular operation occupies an area of the operating member covering a plurality ofthe contact areas provided thereon.

Thus, depending on the size ofthe operating region, a suitable number of switch structures, each comprising a pair of contact areas with associated click-action portions and spaces, will be covered. This means that whatever part of the operating region is pressed by an operator at least one pair of contact areas will be actuatedwith acorresponding clickaction. Hence,a positive switch action can be accomplished regardless of the size of the operating region.

The contact areas for a particular operating region will generally be wired in parallel. In a preferred embodiment, a single sheet or coasting of conductive material can serve to provide a plurality of contact areas so that separate wiring is not necessary.

An embodiment ofthe invention will now be described byway of example only with reference to Fig. 3 ofthe accompanying drawings which is a schematic cross-sectional view of the structure of a keyboard switch arrangement in accordance with the invention. In Figure 3, the arrangement is similar in some respects to that of Fig. 1, there being an operating member 11, a spacer 12, a switch sheet 13 which initiates a click action, a pattern of contact areas 14, a support member 15 and spaces 16. In this arrangement, however, the required operating region is a large portion designated bythe reference numeral 17, comprising two switch structures, and the contact areas 14 are connected in parallel, in this case being integ rally formed.It will be noted thatthere is no support underthe switch sheet between the contact areas.

1. A keyboard switch arrangement comprising a flexible operating member, a switch sheet, a plurality of contact areas provided on the operating member and a plurality of corresponding contact areas provided on the switch sheet, the switch sheet having a plurality of portions, corresponding to the contact areas, which are capable of a click action and there being a plurality of spaces each defined between a corresponding pairofcontact areas, wherein an operating region corresponding to a particular operation occupies an area of the operating member covering a plurality of the contact areas provided thereon.

2. A switch arrangement as claimed in Claim 1 wherein the contact areas are arranged in parallel the operating region.

3. A keyboard switch arrangement substantially as hereinbefore described with reference to Figure 3 of the accompanying drawings.

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

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Keyboard switch This invention relates to a keyboard switch ofthe type having a wide applicability as an operational input switch for various electrical and electronic instruments such as computers or pocket calculators wherein confirmation of input at the time of the switch operation is made possible by virtue of a click action at the time ofthe switch operation. A proposal forthis type of switch is illustrated in Fig. 1, which is a schematic cross-sectional view of the structure of a keyboard switch arrangement capable of click action. This switch arrangement comprises a flexible operating member 2 having a plurality of contact areas 1 disposed thereon in a desired pattern. Aflexible switch sheet 6 is provided underneath the operating member 2 and has a corresponding pattern of contact areas 5 placed so as to match the areas 1, being opposed thereto across switch operation spaces 3 provided by use of an insulation spacer 4. Each contact area 5 is capable of individually carrying outa switch operation in coordination with its corresponding contact area 1,the flexible switch sheet having a shape suitable for initiating click actions. A support member 8 which accommodates the switch sheet 6 is provided with spaces 7 necessary for accommodating click actions by over-centre movement of portions of the sheet 6. At the same time it supports and fixesthe members thereabove including the switch sheet 6. A bonding layer9 e.g. made of a suitable bonding material for the consituent members is provided. Fig. 2 is a perspective view of part of a keyboard utilising a switching arrangement. Forthe keyboard 10 one wishes to freely choose the size of the operational regions as illustrated bythesmall regionsAto Dand large regions E and F. In the case of particularly large operational regions such as E and F, if structure of the underlying switch arrangement is as shown in Figure 1, suitable switch operation cannot always be accomplished by indiscriminate press operation of the operatoranditisextremelydifficultto build a click operational part as a single unit and let it respond to such a broad operational region in a satisfactory manner. An object ofthe present invention is to avoid the above problem. Thus, according to the invention there is provided a keyboard switch arrangementcompris- ing a flexible operating member, a switch sheet, a plurality of contact areas provided on the operating member and a plurality of corresponding contact areas provided on the switch sheet, the switch sheet having a plurality of portions, corresponding to the contact areas, which are capable of a click action and there being a plurality of spaces each defined between a corresponding pairofcontact areas, wherein an operating region corresponding to a particular operation occupies an area of the operating member covering a plurality ofthe contact areas provided thereon. Thus, depending on the size ofthe operating region, a suitable number of switch structures, each comprising a pair of contact areas with associated click-action portions and spaces, will be covered. This means that whatever part of the operating region is pressed by an operator at least one pair of contact areas will be actuatedwith acorresponding clickaction. Hence,a positive switch action can be accomplished regardless of the size of the operating region. The contact areas for a particular operating region will generally be wired in parallel. In a preferred embodiment, a single sheet or coasting of conductive material can serve to provide a plurality of contact areas so that separate wiring is not necessary. An embodiment ofthe invention will now be described byway of example only with reference to Fig. 3 ofthe accompanying drawings which is a schematic cross-sectional view of the structure of a keyboard switch arrangement in accordance with the invention. In Figure 3, the arrangement is similar in some respects to that of Fig. 1, there being an operating member 11, a spacer 12, a switch sheet 13 which initiates a click action, a pattern of contact areas 14, a support member 15 and spaces 16. In this arrangement, however, the required operating region is a large portion designated bythe reference numeral 17, comprising two switch structures, and the contact areas 14 are connected in parallel, in this case being integ rally formed.It will be noted thatthere is no support underthe switch sheet between the contact areas. CLAIMS

1. A keyboard switch arrangement comprising a flexible operating member, a switch sheet, a plurality of contact areas provided on the operating member and a plurality of corresponding contact areas provided on the switch sheet, the switch sheet having a plurality of portions, corresponding to the contact areas, which are capable of a click action and there being a plurality of spaces each defined between a corresponding pairofcontact areas, wherein an operating region corresponding to a particular operation occupies an area of the operating member covering a plurality of the contact areas provided thereon.

2. A switch arrangement as claimed in Claim 1 wherein the contact areas are arranged in parallel the operating region.

3. A keyboard switch arrangement substantially as hereinbefore described with reference to Figure 3 of the accompanying drawings.