Traveling wave ultrasonic motor
US6388365B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 2000 |
| Grant date | May 14, 2002 |
| Priority date | — |
| Expiry date | Oct 3, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02N2/0065
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A traveling wave ultrasonic motor includes a ring-shaped stator (2) and two groups of electromechanical transducers (3 to 6). Each group comprises a pair of diametrically opposed longitudinal transducers, polarized in opposite directions, disposed perpendicularly to the stator (2). The transducers are in permanent contact with the stator (2) and excited by an alternating current with a &pgr;/2 phase shift between the groups so as to produce a traveling wave-like deformation on the surface of the stator (2). The motor comprises at least one rotor (1) held elastically in contact with the stator (2) for the rotational driving thereof by the traveling wave produced on the stator. The stator is in contact with the rotor only via two or four equal and diametrically opposed segments (9, 10) whose aggregate span is at most equal to a wavelength of the traveling wave produced in the stator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.