Rotation angle detection apparatus
US7323866B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 3, 2007 |
| Grant date | Jan 29, 2008 |
| Priority date | — |
| Expiry date | Apr 3, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/145
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rotation angle detection apparatus is capable of preventing an eddy current and radio wave noise from being transmitted from outside to a yoke and a permanent magnet through a metal plate, and thence to a non-contact sensor through radiation as it is. The apparatus includes a yoke, a permanent magnet that is arranged on an inner wall surface with magnetic flux flowing from its N pole to its S pole through an inner space thereof, a metal plate formed integral with the yoke and the permanent magnet through a resin by insert molding, and a non-contact sensor arranged in the inner space of the permanent magnet. Between the metal plate and the individual end faces of the yoke and the permanent magnet, there is interposed a high impedance member that prevents radio wave noise from flowing from the metal plate to the yoke and the permanent magnet.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.