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:
Feb. 01, 1983
Filed:
Jul. 02, 1981
Applicant:
Inventor:
Kenji Fujikawa, Kawasaki, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
352140 ;
Abstract
This specification discloses a moving picture camera provided with a cam cylinder for transferring movable lens groups, a motor for rotating the cam cylinder, a rotary type resistor having its adjusting shaft coupled to a cam ring through a gear train and to which a constant voltage is applied, a differentiation circuit for differentiating the output voltage of the resistor to detect any variation in rotational speed of the cam cylinder, and an electric circuit for inputting the output signal of the differention circuit to the motor with a zooming speed indication signal, thereby eliminating any speed fluctuation during zooming.