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:
Jun. 16, 1998
Filed:
Oct. 07, 1994
Ryoichi Suganuma, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A driving device for an ultrasonic motor has a limit detecting circuit for detecting that the drive voltage for the ultrasonic motor has reached a limit, and, in response, a drive voltage limiting circuit controls the drive voltage so as not to go beyond the limit value. Such control is conducted on the voltage or frequency of a signal for driving the ultrasonic motor. In another aspect of the invention, a drive state detecting circuit detects the drive state of the ultrasonic motor, and a drive frequency (or voltage) setting circuit controls the frequency (or voltage) of a signal for driving the ultrasonic motor so as to attain the maximum efficiency in the motor, based on the output of the drive state detecting circuit.