Patent · US Expired

Absolute linear encoder and method of production utilizing index and counter channels

US5825307A · kind A · utility

21Cited by
12References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 5, 1997
Grant dateOct 20, 1998
Priority date
Expiry dateFeb 5, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D5/34792
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An absolute linear encoder includes an index channel and at least two counter channels. The spacing between markings on the index channel is constant, and the spacing between markings on the first and second channels is predetermined so that the positions of the markings in the first and second channels vary so as to provide a unique signature for each position along the encoder. The linear encoder includes quadrature channels to provide increased resolution and to determine the direction of translation. The encoder is provided with a detector unit to detect positions of the markings in each channel, and a processing unit to calculate an absolute position from the detected marking positions. A method of producing the absolute linear encoder includes selecting spacings for markers in the quadrature, index, first and second channels in order to provide a desired resolution and encoder length.

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