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:
Dec. 21, 1999
Filed:
Jun. 27, 1996
Ryoichi Suganuma, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A driving device for an ultrasonic wave motor, comprises: a stator member having an electrostrictive member and a resilient member, and adapted to generate travelling vibration wave in the resilient member by excitation with the electrostrictive member; a moving member maintained in pressure contact with the stator member and driven by the travelling vibration wave; a reference pulse oscillator circuit for generating reference pulses of a frequency determined corresponding to a required moving speed of the member; an encoder for generating pulses relating to the amount of movement of the moving member; a phase difference signal generating circuit for generating a phase difference signal corresponding to the phase difference between the reference pulses from the reference pulse oscillator circuit and the output pulses of the encoder; and an AC voltage forming circuit for forming AC voltage signals to be supplied to the electrostrictive member, based on the phase difference signal.