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. 12, 1978
Filed:
Sep. 30, 1977
Applicant:
Inventors:
Yasuo Ishiguro, Tokyo, JP;
Kenji Wakazono, Tokyo, JP;
Assignee:
Copal Company Limited, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
354234 ; 354 51 ;
Abstract
A controlling circuit for electric shutters comprising at least one constant current circuit, a pair of capacitors to be charged in advance by a current source battery through the constant current circuit and a pair of driving coils to be energized in turn by discharge currents of the pair of capacitors to start a shutter blade opening motion and closing motion so that the current source battery of a comparatively small capacity may be effectively used.