Drive control device of vibration wave motor
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jul 15, 2003
Grant Date -
Jan 17, 2002
app pub date -
May 1, 2001
filing date -
May 8, 2000
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
The present invention relates to a vibration wave motor which is configured to prevent abnormal noise from being produced at a start time or a stop time and, more particularly, to a control device for a vibration wave motor which obtains a driving force by applying a periodic voltage to an electro-mechanical energy conversion element so as to generate in a vibration member thereof a plurality of standing waves having a phase difference therebetween, the plurality of standing waves being synthesized to generate a driving vibration in the vibration member. The control device comprises a frequency control circuit which varies a frequency of the periodic voltage and, when a driving force of the vibration wave motor is to be stopped, varies the periodic voltage so as to achieve a predetermined frequency at which a rotational speed of the vibration wave motor becomes zero, and a voltage control circuit which gradually lowers a voltage level of the periodic voltage to a predetermined voltage and then, after the frequency control circuit varies the frequency so as to achieve the predetermined frequency, stops energization of the vibration wave motor.
First Claim
Family
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully