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:
Oct. 17, 1995
Filed:
Jul. 20, 1993
Reiji Mitarai, Hachioji, JP;
Hiroaki Takeishi, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In a travelling wave driven motor and its driving apparatus, the absolute value of a speed is controlled using a vibration amplitude value as a main manipulation variable. A plurality of frequencies are selectively generated as sub manipulation variables, and are used as the driving frequencies of the motor. In a precision positioning operation (precision operation mode), an electric signal, which has a first selected frequency separated by a predetermined value from a resonance point of a stator of the motor, and has a predetermined amplitude value, is supplied to a piezoelectric element. In a high-speed feed operation (coarse operation mode), an electric signal, which has a second selected frequency near the resonance point of the stator, and has a predetermined amplitude value, is supplied to the piezoelectric element.