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. 09, 1989
Filed:
Apr. 28, 1986
Toru Kameyama, Tokyo, JP;
Ken Miyagi, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A safety device for use in a recording apparatus controls the on/off operation and prevents the malfunction of motors for driving a gear flange to rotate a light sensitive drum and for driving an actuating gear and other driving members in accordance with a signal indicative of the reference rotational frequency received from an oscillator and a signal indicative of the rotational frequency of each motor. A motor control circuit is used including motor drivers for controlling the operation of said motors and a fault detection circuit for detecting the malfunction of said motors by comparing an adder output indicative of said motors' rotational frequencies with threshold values in a comparator, thereby ascertaining the long-term use of the light sensitive drum.