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. 20, 1990
Filed:
Feb. 03, 1989
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A motor-driven camera of the so-called prewind type in which a film is preliminary wound to effect a prewinding action and then the film is rewound for every photographing shot, includes an electric film counter which counts the number of frames on the basis of a signal generated according to the movement of the film; a control circuit which determines the number of photographable frames on the basis of a counted value of the electric film counter; a detection circuit which detects the completion of the prewinding action by detecting that the film ceases to move; and a judgment circuit which is arranged to detect the state of the above-stated signal after the lapse of a predetermined period of time from the completion of the prewinding action detected by the detection circuit, to judge whether or not a change in the counted value of the electric film counter is necessary.