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:
Oct. 26, 1993
Filed:
Jul. 30, 1992
Jiro Kazumi, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A camera having a shutter device including leading and trailing curtains includes a first switch arranged to detect the ready-to-travel state and the travel-completed state of the leading curtain, a second switch arranged to detect the ready-to-travel state and the travel-completed state of the trailing curtain, and a decision circuit arranged to determine that the shutter device is abnormal, either when the ready-to-travel state of the leading curtain is not detected by the first switch or when that of the trailing curtain is not detected by the second switch, before an operation of the shutter device. The decision circuit also determines that the shutter device is abnormal, after completion of control over the travels of the leading and trailing curtains by the shutter device, if the travel-completed state of the leading curtain is not detected by the first switch within a predetermined period of time after the travel-completed state of the trailing curtain is detected by the second switch.