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:
Dec. 25, 1979
Filed:
Sep. 14, 1977
Osamu Hirata, Tokyo, JP;
Yuji Harada, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An electronic desk-top calculator includes a bottom casing for the calculator on the inner surface of which bottom casing there are provided fixed contacts, and a flexible plate having thereon pairs of contacts provided with wiring conductors therefor. These pairs of contacts are so arranged at the positions in registry with the fixed contacts as to form a matrix. The fixed contacts act as bridging contacts and comprise electrically conductive material containing carbon particles. The pairs of contacts and wiring conductors have a first electrically conductive layer. An insulative layer of moisture-resistive material overlies the first conductive layer except those terminal ends of the wiring conductor which serve as contacts or electrical connectors. The exposed portions of the first conductive layer which function as switch contacts have an additional layer of electrically conductive material containing carbon particles.