Patent · US Expired

Length measuring device

US4400890A · kind A · utility

15Cited by
3References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 26, 1981
Grant dateAug 30, 1983
Priority date
Expiry dateOct 26, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B7/02
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A length measuring device has a magnetic scale body including at least one origin signal magnetic section and a measurement signal magnetic section forming a magnetic grating, the magnetic scale body having a uniform frictional surface formed over the entire effective length of the scale body, and a detecting head body including an origin detecting head for detecting an origin signal and a measurement detecting head for detecting a measurement signal and provided with a scraper in elastic contact with the frictional surface of the magnetic scale body, the detecting head body moving relative to the magnetic scale of the body along the length of the latter.

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