Non-contact type rotation-angle sensing device
US6867584B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2004 |
| Grant date | Mar 15, 2005 |
| Priority date | — |
| Expiry date | Apr 2, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/147
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a non-contact type rotation-angle sensing device, a rotation angle sensor (9) having magnetoresistance elements detects a rotation angle of an object to be measured. The object is rotatable round a rotary shaft (2) with respect to the rotation angle sensor (9) and includes a permanent magnet (5, 6). The permanent magnet (5, 6) is disposed symmetrically about said rotary shaft (2) of said object, and a magnetic element (7, 8) is disposed on said object between said permanent magnet (5, 6) and the magnetoresistance elements. In the non-contact type rotation-angle sensing device of above constitution according to the invention, linearity is secured by reducing magnetic hysteresis of the sensor output with respect to the rotation angle, thus a small-sized permanent magnet and reduction in cost being achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.