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:
Jul. 17, 1979
Filed:
May. 08, 1978
Applicant:
Inventors:
Assignee:
Copal Company Limited, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ; G03B / ;
U.S. Cl.
CPC ...
361187 ; 354 51 ; 354234 ;
Abstract
An exposure controlling circuit for electric shutters incorporating therein a voltage drop detecting circuit which will issue a signal for passing a current to a coil for closing a shutter when a current source voltage becomes lower than a predetermined voltage in order to prevent the shutter closing motion from being made unable to be made by the drop of the current source voltage after the shutter is opened. This controlling circuit further includes a driving circuit for making an indication within the field of vision of the view finder of a photographic camera when a signal is issued from the voltage drop detecting circuit.