Patent · US Expired

Apparatus for detecting position of a rotating element using a two-grating moire pattern

US4775788A · kind A · utility

7Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 3, 1986
Grant dateOct 4, 1988
Priority date
Expiry dateOct 3, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/37131
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

The position and motion of a rotating element is determined by using a two-grating moire pattern. Movement of the element causes a projected scale image representing radiation reflected from the element to shift relative to a fixed grating thereby generating moire fringes. The accumulated fringes serve to measure absolute position and motion of the element.

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