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:
Aug. 02, 1983
Filed:
Apr. 07, 1981
Hitomi Tojiki, Hachioji, JP;
Teruo Iwasawa, Mitaka, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A motor control apparatus which includes a pulse generator for providing a first signal for specifying the operational condition of a motor, and a motor driver for providing a second signal for driving the motor when the first signal is at a first level and providing a second signal when the first signal is at a second level. The motor control apparatus further includes a comparator, which compares the back electromotive force of the motor with a reference level when the first signal is at the second level and providing a third signal when the back electromotive force is within a given level range prescribed by the reference level. A switch circuit closes a circuit path through which a back electromotive force current produced by the back electromotive force flows when the second and third signals are provided, thereby applying electromagnetic braking with respect to the rotation of the motor.