The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 22, 1986
Filed:
Sep. 21, 1984
Takao Nagashima, Tokyo, JP;
Topre Corporation, Tokyo, JP;
Abstract
A keyboard switch is provided with an insulating substrate, a first electrode laid on the insulating substrate, a second electrode formed of a conical coil spring and facing the first electrode, a dielectric disposed on the first electrode, a button positioned on the top portion of the second electrode, and a rubber cap disposed between the button and second electrode, for giving snap feeling to an operator when the button is depressed and the capacitance of the switch exceeds a given value. The capacitance varies with the change in the facing area which changes substantially in proportion to the depth of depression of the button. The switch is capacitive-coupled for a switching operation and the snap feeling is given to the operator when the capacitance exceeds the given value.