Patent · US Expired

High accuracy optical shaft encoder system

US4224515A · kind A · utility

14Cited by
1References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 27, 1978
Grant dateSep 23, 1980
Priority date
Expiry dateOct 27, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P23/22
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An optical shaft encoder system for measuring electrically powered motor shaft speed, including a system for increasing the sinosoidal encoder output waveforms by a multiplication factor, converting the product of the multiplied waveforms to square waves, comparing the waveforms to a reference waveform and generating a correction signal which is fed back to the motor through servo circuitry, thereby correcting errors in motor shaft rotational speed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.