Driving device, light amount controller and shutter
US6710563B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 2002 |
| Grant date | Mar 23, 2004 |
| Priority date | — |
| Expiry date | Mar 11, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B9/08
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
There is provided a small-sized and slim driving device which is easy to manufacture and capable of producing high output. A magnet has a cylindrical shape, and at least the outer peripheral surface of the magnet is circumferentially divided into n sections magnetized so as to have alternately different poles. The magnet can rotate about a rotational axis of the cylindrical shape. A coil is arranged axially of the magnet and parallel thereto. An outer magnetic pole portion is disposed to be magnetized by the coil, and has a plurality of hair comb tooth-shaped portions opposed to the magnet and arranged around the magnet such that an angle corresponding to the circumferential width of each of the hair comb tooth-shaped portions opposed to the magnet about the rotational axis of the hollow cylindrical shape of the magnet is equal to a predetermined angle A. An inner magnetic pole portion is disposed to be magnetized by the coil, and has a hollow cylindrical shape opposed to the inner peripheral surface of the magnet. The predetermined angle A is set to such a value that a rotational force acts on the magnet to return to a position in which a circumferential center of each of n magnet…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.