Rotational position detecting apparatus
US4369405A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1980 |
| Grant date | Jan 18, 1983 |
| Priority date | — |
| Expiry date | Jul 8, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P13/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rotational position detecting apparatus includes a rotating member magnetized to induce a large number of magnetic poles on the periphery thereof except at a portion indicative of a rotational reference position, and a pair of magnetically sensitive elements for detecting the magnetic flux from the magnetic poles so as to generate rotational angle signals and reference position signals. The pair of magnetically sensitive elements are positioned side by side such that their output signals generated in response to the magnetic flux from the magnetic poles are different in phase by half the period, and the difference between the outputs of the magnetically sensitive elements is obtained by a differential circuit whose output has an amplitude which is two times the amplitude of the outputs of the magnetically sensitive elements. The magnetic poles on the periphery of the rotating member are dropped out at the reference position in such a manner that the output AC component of the respective magnetically sensitive elements is dropped out at the reference position in a point symmetrical manner on both sides of the zero level of the AC component, thus stably supplying the rotational ang…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.