Magnetic rotary encoder for detection of absolute values of angular displacement
US4274053A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1979 |
| Grant date | Jun 16, 1981 |
| Priority date | — |
| Expiry date | Mar 5, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic rotary encoder for detecting the absolute value of an angular displacement using magneto-resistors is disclosed. A drum, disk or cup-shaped rotary member is attachable to a rotatable shaft. A magnetic medium divided into a plurality of tracks is provided on a surface of the rotary member. Each of the tracks produces magnetic fields changing in magnitude and direction as the rotary member revolves. Alternatively, a plurality of permanent magnets are provided on the surface of the rotary member to produce the alternating magnetic field as the rotary member revolves. A plurality of magneto-resistors are provided in the vicinity of the rotating paths of the tracks and produce analog signals indicative of changes in their electrical resistances. A rotary condition detector receives the analog signals and produces digital signals and/or an analog signal indicative of the angular distance moved by the rotatable shaft in an absolute value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.