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:
Mar. 13, 1979
Filed:
Sep. 30, 1977
Applicant:
Inventors:
Yasuo Ishiguro, Tokyo, JP;
Kenji Wakazono, Tokyo, JP;
Assignee:
Copal Company Limited, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
354267 ; 354234 ;
Abstract
A controlling circuit for electric shutters wherein, in an electric shutter adapted to start a shutter closing moton by energizing a driving coil with a discharge current from a capacitor, the capacitor is made to be discharged by a voltage drop detecting circuit provided so that the shutter may be positively closed even in case a current source switch is opened by an unexpected accident in the course of an exposure controlling operation.