Circuit for multiplying resolution and for determining the direction of displacement
US5955878A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1997 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Sep 29, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P13/045
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A multipole magnetic encoder is movable past two fixed analog sensors delivering sinusoidal signals (S.sub.1, S.sub.2) phase-shifted by .pi./2. A generator produces 2n sinusoidal signals (S.sub.i) of the same amplitude (A) as the signals (S.sub.1, S.sub.2), phase-shifted by .pi./n. An analog multiplexer delivers a signal (S) consisting of 2n successive portions of signals (S.sub.i). An acquisition device determines a maximum envelope (E) of the signals (S.sub.i). Two of switching thresholds (L.sub.i) and (L.sub.j) are generated proportional to the envelope (E). Two comparators compare the signal (S) with the thresholds (L.sub.i) and (L.sub.j), and deliver binary signals (A.sub.i) and (B.sub.j). Two combining devices combine the binary signals (A.sub.i) and (B.sub.j), each delivering a high resolution signal of 2m*n periods in the interval of one period of one of the sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.