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:
Sep. 21, 1982
Filed:
Mar. 04, 1981
Shinji Urata, Tachikawa, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A time determination circuit for an automatic or manual exposure camera in which a single capacitor is utilized for both a power maintaining time determination circuit and a shutter controlling time determination circuit to thereby significantly reduce the space required for the electronics in the camera and thereby reducing the cost. The single capacitor is charged either through a constant current source controlled by an electromagnet switch which is in turn operated in response to raising of the camera mirror or through a transistor operated in response to a shutter time calculation circuit. A terminal voltage of the capacitor is compared with a fixed voltage and the comparison output is amplified to control an electromagnet.