Apparatus and method for driving an ultrasonic motor to reduce rise response time
US6437480B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 22, 1997 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Feb 9, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02N2/163
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for driving an ultrasonic motor to reduce the rise response time. The ultrasonic motor is drivable at different frequencies and has a desired target speed, each frequency corresponding to a respective speed and a respective torque. The ultrasonic motor enters a specific mode after being started and driven. When the ultrasonic motor is started, a drive control unit drives the ultrasonic motor at a frequency corresponding to approximately a maximum torque. When the ultrasonic motor enters the specific mode, the drive control unit drives the ultrasonic motor at a frequency corresponding to approximately the target speed. Alternatively, the ultrasonic motor can be driven at different drive voltages, each drive voltage having corresponding frequencies, with each frequency of each drive voltage corresponding to a respective speed and a respective torque. The ultrasonic motor enters a specific mode after being started and driven. When the ultrasonic motor is started, the drive control unit selects a drive voltage, and drives the ultrasonic motor at the selected drive voltage and at a frequency of the selected drive voltage which corresponds to a maximum torque. Whe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.