Digital absolute position encoders
US5574445A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 1994 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Dec 8, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/2497
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A digital absolute position encoder is provided for determining absolute position of a first member with respect to a second member. The absolute position is determined within a resolution cell of L/2.sup.n, where n is an integer and L is a predetermined span. One of the members has a plurality of, m, tracks of binary indicia distributed over the predetermined span, L, where m is an integer less than n. The other member has a plurality of indicia detectors disposed on the second member for detecting the binary indicia. With such an arrangement, an encoder is provided having "a unit-distance code", yet uses less tracks than that used with a conventional Gray code encoder. Further, the encoder has a reduced number of transitions than that required on the track used with a conventional Gray code encoder. Both of these features simplify the design and fabrication for a given encoder resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.