Membrane touch switches

摘要

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.