Drive unit provided with position detecting device
US7315164B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 2006 |
| Grant date | Jan 1, 2008 |
| Priority date | — |
| Expiry date | Feb 26, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2205/0069
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A drive unit in accordance with the present invention is provided with a magnetic field generating member generating a magnetic field, a magnetic field detecting device constituted by first, second and third magnetic field detecting elements detecting the magnetic field, and a piezoelectric actuator moving the magnetic field generating member. When executing a relative positioning between the magnetic field generating member and the magnetic field detecting device on the basis of a detection result by the magnetic field detecting device, a first positioning is executed on the basis of the detection result of the first and second magnetic field detecting elements in a predetermined region, and a second positioning is executed on the basis of the detection result of the third magnetic field detecting element at a predetermined point apart from the predetermined region, within a movable range in which the magnetic field generating member moves. In accordance with the structure, it is possible to position the movable body at a high precision, even in the case that a plurality of position detecting points of the movable body of the drive unit exist at a wide interval.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.