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:
May. 05, 1998
Filed:
Dec. 17, 1996
Fumio Shimada, Saitama-ken, JP;
Canon Denshi Kabushiki Kaisha, Saitama-ken, JP;
Abstract
A shutter device comprises a shutter blade which operates according to an exposure operation, a first blade driving spring for giving an urging force working in a predetermined direction to the shutter blade substantially over an entire operating range of the shutter blade, a second blade driving spring for giving the shutter blade an urging force working in the same direction as the first blade driving spring, and a charging mechanism for charging the first blade driving spring and the second blade driving spring. Since the charging mechanism includes a first charging member which travels to charge the first blade driving spring and a second charging member which travels to charge the second blade driving spring, the timings of charging the respective springs and the torques required to charge the respective springs can be optimally set.