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. 04, 1990
Filed:
Feb. 07, 1990
Akira Suzuki, Tokyo, JP;
Kenichi Watabe, Tokyo, JP;
Copal Company Limited, Tokyo, JP;
Abstract
A focal plane shutter includes a first blade group which is moved forward from an unfolding state to an overlapping state to start an exposure in response to the release of a first blade driving spring and a second blade group which is moved forward from an overlapping state to an unfolding state to terminate the exposure in response to the release of a second blade driving spring. The force of the driving springs for applying the impellent force to the blade groups is removed from the corresponding blade groups before each of the blade groups reaches an end of forward movement so that the blade groups are moved by the force of inertia. The driving spring for applying the impellent force to the blade groups is engaged with a first arm formed on one end of a swingably supported brake lever before the blade group reaches the end of forward movement so that a second arm formed on the other endd of the brake lever is rotated to prevent the movement of the blade group. Since the blade groups are moved to the end of forward movement while receiving the braking force by engagement with the second arms of the corresponding brake levers, shock or oscillation at the termination of forward movement is reduced.