To effectively prevent a flat switch, having as dome-shaped elastic diaphragm, comprising a film having a through hole for an air channel, keeping the atmospheric pressure inside the flat switch when depressing and releasing by depressing the flat switch, from defective contact generated when repeating the operation of depressing and releasing the depression.
The flat switch comprises a base board 16 having a fixed side terminal 14 and a movable side terminal 15 at one side; a fixed side contact 12 formed to the peripheral part, contacting with the fixed side terminal 14 at all times; a movable side contact 13 formed to approximately central part of the concave side, capable of contacting with and separating from the movable side terminal 15; the dome-shaped elastic diaphragm 11 put on the base board 16; a holding film 17 covering the diaphragm 11 and the base board 16; and a through hole 18 formed to the holding film 17 at the position slightly distant from the periphery or the diaphragm 11.
HIRAI YASUSHI
KAWAHIRA TETSUYA
