Patent · US Expired

Rotational position detection device

US4743786A · kind A · utility

41Cited by
9References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 19, 1985
Grant dateMay 10, 1988
Priority date
Expiry dateNov 19, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D2205/73
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

This rotational position detection device comprises a stator section including primary and secondary windings and a rotor section disposed in such a manner that it is capable of performing relative rotational displacement with respect to the stator section. A conductive substance portion is provided in the form of a predetermined pattern. The amount of flux passing through the conductive substance portion of the rotor section changes in accordance with a relative rotational position of the rotor section with respect to the stator section and therefore an eddy current flows through the conductive substance portion. Reluctance is caused to change by a loss due to this eddy current and a secondary output signal corresponding to the rotational position is produced in the windings of the stator section. The pattern of the conductive substance portion can be formed easily by using electro-plating or other surface processing technique. The rotor section may be of a shape such that the rate of the reluctance change is enhanced by the combination of the magnetic substance portion and the conductive substance portion.

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