Patent · US Expired

Driving control device for vibration wave motor

US5710491A · kind A · utility

8Cited by
8References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 1995
Grant dateJan 20, 1998
Priority date
Expiry dateJun 7, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02N2/163
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A control device for a motor having a stator that generates traveling vibration waves in an elastic member by the excitation of a piezoelectric member, a rotor pressed to contact with the stator and driven by the traveling vibration waves, and a power supply circuit that generates at least one pair of input alternating voltages which are out of phase for exciting the piezoelectric member, and being driven by the vibration waves, comprises a judgment circuit for judging whether the rotor is in an abnormal operating condition, and an amplifying circuit for increasing the voltage magnitude of a pair of alternating voltages from the power supply circuit to a value greater than a predetermined value exceeding the rated voltage of the motor, in response to the fact that the judgment circuit judges that an abnormal operating condition of the motor is in effect.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.