US 4,302,647 A · Membrane touch switches

Abstract

A laminated touch switch panel includes a lowermost insulating board having foil contacts on its top surface and a perforated uppermost board having foil contacts on its bottom surface. A perforated insulating spacer sheet has its bottom surface interfacing with the top of the lowermost board and its upper surface interfacing with an intervening flexible perforated membrane. The membrane has foil contacts on its upper surface which are normally closed with respect to the contacts on the bottom of the uppermost board and has contacts on its lower surface which are normally open with respect to the contacts on the lowermost board. Flexing the membrane with a force applied through the uppermost board opens the normally closed contacts and closes the normally open contacts. In one embodiment, contacts are kept normally closed with resilient elements that apply a force on the membrane which is overcome to open the contacts by applying a force through an aperture in the uppermost board.

Claims7

Dependent claims

A touch switch device comprising:

a planar substrate member,
a spacer sheet superimposed on said substrate member and having an aperture defining a recess which has a depth substantially equal to the thickness of the sheet,
a deflectable membrane having a nominally top surface and a nominally bottom surface superimposed over said sheet and extending over said recess, said membrane having first thin short circuiting switch contact means on its top surface aligned with said recess,
a rigid insulating member having its nominally bottom surface superimposed on said top surface of the membrane and having thin spaced apart switch contact elements on its bottom surface aligned with and normally in contact with said contact on the top surface of the membrane, said rigid insulating member having an aperture aligned with said recess, and
plunger means for extending into said aperture in the insulating member and being movable to deflect said membrane in the vicinity of said recess to cause said contact on the membrane to separate from the contact elements on said insulating member.

2 more elements

A touch switch device comprising:

a planar nonconductive substrate member,
thin spaced apart foil contact elements on the nominally top surface of said substrate member, said contact elements being part of a normally open touch switch,
an insulating spacer sheet having a nominally top surface and a nominally bottom surface superimposed on the top surface of said substrate and having an aperture aligned with said contact elements,
a deflectable membrane having a nominally top surface and a nominally bottom surface superimposed on the top surface of said spacer sheet, said membrane having thin foil short circuiting contact means on its bottom surface aligned with said aperture in the spacer sheet and being another part of said normally open switch and having thin foil short circuiting contact means on its top surface located over the contact means on its bottom surface, said last named contact means being part of a normally closed switch, and
a rigid planar insulating member having its nominally bottom surface superimposed on the top surface of the membrane and having an aperture aligned with said short circuiting contact on the top surface of the membrane, and thin spaced apart foil contact elements on the bottom surface of said insulating member adjacent its aperture and forming another part of said normally closed switch and being normally engaged simultaneously by said short circuiting contact on the top surface of said membrane,
deflection of said membrane by a touch force applied to its top surface causing said short circuiting contact on the top surface of said membrane to separate from said contact elements on the bottom surface of said insulating member to thereby open said normally closed switch and to cause said short circuiting contact on the bottom surface of said membrane to deflect and engage said contact elements on said substrate member to thereby close said normally open switch.

3 more elements

Dependencies are inferred from the claim text.

Membrane touch switches

Life of this patent

Membrane touch switches

Life of this patent

Abstract

Claims7