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:
Sep. 04, 1990
Filed:
Oct. 10, 1989
Applicant:
Inventors:
Etsuro Furutsu, Kawasaki, JP;
Kazuhiro Izukawa, Yokohama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
310316 ; 310317 ;
Abstract
In a speed control circuit for a vibration wave motor, when a level of a periodic signal applied to the motor is of first level, a frequency of the periodic signal is changed between a first frequency and a second frequency to change a speed between a first velocity and a second velocity, and when the frequency reaches the second frequency, the signal level is switched from the first level to the second level and the frequency is shifted by a predetermined amount toward the first frequency and then toward the second frequency so that the speed is changed from the second velocity to a third velocity.