Membrane keyboard switch mounting

1. A keyboard comprising

a matrix multilayer switch comprising:

a first flexible sheet with a first and second surface with electrical circuit paths and plural switch contacts deposited on said first surface thereof;

a second flexible sheet with electrical circuit paths and plural switch contacts deposited on a first surface thereof;

a spacer sheet with at least an aperture formed therein, positioned between said first and second flexible sheets and with said aperture aligned with portions of said electrical circuits on each of said sheets to form a passage through which said circuit on said second flexible sheet may contact said circuit on said first flexible sheet and with said first surfaces in face-to-face relation with faces of said spacer,

at least a zone of adhesive interposed between said spacer and each of said flexible sheets to form a multilayer structure with each of said spacer and sheets restricted from movement with respect to each other in the plane of said spacer sheet; and

a rigid support plate and adhesive engaging a first surface thereof, said multilayer switch adhesively attached to said rigid support plate, said adhesive engaging said rigid support plate comprising at least a spot of adhesive localized at and positioned between said support plate and said multilayer switch and adjacent said each of said switch contacts and engaging said second surface of said first flexible sheet, thereby stabilizing said electrical circuit path on said first flexible sheet, the substantial portion of the remainder of said second surface remaining without adhesive, and

an actuator means aligned with and operable manually to actuate said multilayer switch, comprising a keybutton and a switch engaging member operable upon displacement of said keybutton to deflect switch contacts on said second sheet into contact with said switch contacts on said first sheet.

2. The keyboard of claim 1 wherein said rigid support plate is curved to a radius approximately the curve defined by the fingers of an operator as said fingers are extended to engage said keybuttons and where said plural switch contacts on said first sheet are fixedly positioned relative to said plate by said spots of adhesive between said plate an said first sheet.

3. The membrane switch structure of claim 2 wherein said spot of adhesive is substantially circular and is positioned between and aligned with said switch contacts and said support means.

4. The keyboard of claim 3 wherein said first flexible sheet has formed therein a hole extending from said first side to said second side thereof and communicating with said aperture and an area between said first flexible sheet and said rigid support plate where no adhesive exists.

5. The keyboard of claim 4 wherein said adhesive circular pattern comprises a sector, which has no adhesive, corresponding in location to the position of said hole, thereby creating a communication between said hole and said region of no adhesive between said first flexible sheet and said rigid support plate.

6. The keyboard of claim 2 wherein said multilayer structure is further adhesively attached to said support plate by adhesive deposited in a substantially continuous band adjacent three edges of said first flexible sheet and intermediate said sheet and said rigid support plate.

7. The keyboard of claim 3 wherein said multilayer structure is further adhesively attached to said rigid support plate by adhesive deposited in a substantially continuous band adjacent three edges of said first flexible sheet and intermediate said first sheet and said rigid support plate.

8. The keyboard of claim 4 further comprising additional regions of adhesive extending generally outward from said region of adhesive, thereby fixedly adhering said first flexible sheet to said rigid support plate in regions where objects may engage said membrane switch without causing one of said switch contacts to contact the other of said switch contacts.

9. The keyboard of claim 1 further comprising a frame for supporting said actuator means and said frame attached through said membrane switch and to said rigid support plate.

10. The keyboard of claim 9 wherein said frame further comprises tenons extending through said rigid support plate and deformed to prevent removal of said frame from said plate.

11. A keyboard comprising:

a membrane switch structure having a plurality of switch positions having a laminate of at least three layers and a rigid support member, with said member selectively adhered to said laminate with spots of adhesive positioned between said member and said laminate in areas corresponding to each of said switch positions, said middle layer of said laminate comprising a hole formed at the position corresponding to each of said switch positions, thereby defining in cooperation with the other two layers a cavity, and air exhausting means communicating between said cavity and the portion of space between said laminate and said support member having no adhesive adhering the laminate and said support member.

12. The keyboard of claim 11 wherein said spot of adhesive is substantially circular.

13. The keyboard of claim 12 wherein said laminate is further adhesively attached to said support member by adhesive deposited in a substantially continuous strip adjacent three edges of said laminate and intermediate said laminate and said support member.