Brushless DC motor and image pickup apparatus
US8030865B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 2009 |
| Grant date | Oct 4, 2011 |
| Priority date | — |
| Expiry date | Apr 11, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/16
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A brushless DC motor configured to drive a driven member includes a rotor having a magnet, a stator having a coil configured to provide a rotational force to the magnet, a position detector configured to output a first signal that is periodic, in accordance with a rotating position of the rotor, a signal generator configured to generate a second signal by adding a lead angle to a phase of the first signal output from the position detector, an excitation switch configured to select an excitation to the coil in accordance with the second signal, and a phase change part configured to change the lead angle in accordance with at least one of a position and a moving direction of the driven member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.