Positioning apparatus using brushless motor
US6998808B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 2003 |
| Grant date | Feb 14, 2006 |
| Priority date | — |
| Expiry date | Oct 15, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/43008
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A positioning apparatus having a brushless motor, a positioning mechanism, and a motor control circuit to rotate a rotor of the brushless motor by sequentially supplying a driving pulse to a plurality of fixed coils of the brushless motor. The motor control circuit includes a driving pulse generator, a present stage number detector to detect a present stage number of the rotor in accordance with an output signal from at least one magneto-sensitive device of the brushless motor, an initializer to move the movable member to at least a forward or a backward traveling limit within the movable range so as to set the rotor present stage number, and a speed reducer to reduce a rotating speed of the brushless motor by reducing power of the driving pulse when the rotor present stage number is equal to at least a forward traveling or a backward traveling stage number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.