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. 06, 1982
Filed:
Jan. 25, 1980
Ryoichi Sado, Saitama, JP;
Shin-Etsu Polymer Co., Ltd., Tokyo, JP;
Abstract
The invention provides a novel push-button switching means for producing an electric signal free from the problems of chattering or bouncing unavoidable in the conventional switches relying on the principle of mechanical contacting and coming apart of the contact points. The inventive push-button switching means comprises a pressure-sensitive unit composed of a resistor body formed of an electroconductive rubbery elastomer exhibiting a minimum in its electric resistivity when subjected to compression with an increasing pushing force reaching a strength in excess of a certain critical strength and a pair of electrodes provided on the surface of the resistor body. When the pressure-sensitive unit is pushed with a force in excess of the critical strength to compress the resistor body and then released, the resistivity of the resistor body exhibits two minimum values in the courses of the pushing and releasing and, correspondingly, two maxima are obtained in the electric current through the resistor body with application of a predetermined voltage between the electrodes. These two successive peaks of current are detected by a detecting circuit which produces a single electric signal in response thereto.