04716262 is referenced by 35 patents and cites 19 patents.

A shielded electrical switch includes a pressure-actuated switch comprised of three layers, the top and bottom layer of which are electrically-conductive and the intermediate layer of which is a spacer layer containing apertures at the switch points. A sealing membrane is coupled over the layered switch, the membrane having thickened push-button supports overlying the switch points. The thickened push-button supports are spaced from the membrane via frustro-conical mounting portions on the membrane. This frustro-conical mounting gives the buttons the sufficient "feel" or resistance when depressed, and also insures that the switch-actuating portions of the membrane will make contact with the upper surface of the switch to insure that the switch points of the upper and lower layers of the switch will make contact via the intermediate layer. The membrane and the sealed, layered switch are, in turn, enclosed in an armored, sealed push-button enclosure. The entire assembly is thus a highly vandal-resistant, low-cost, push-button switch.

Title
Vandal-resistant telephone keypad switch
Application Number
236757
Publication Number
4716262
Application Date
November 22, 1985
Publication Date
December 29, 1987
Inventor
Milton Morse
Fort Lee
NJ, US
Agent
Edward R Weingram
Assignee
Nena Morse
NJ, US
IPC
H01H 13/70
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