Patent · US Expired

Magnetic position and speed sensor with hall probe in an air gap

US5528139A · kind A · utility

56Cited by
2References
38Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 1, 1992
Grant dateJun 18, 1996
Priority date
Expiry dateOct 1, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P3/487
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

This invention relates to a position sensor featuring a stator (1) defining an air gap inside of which a mobile magnet (3) integral with a coupling shaft (4) moves. The sensor features a Hall probe (12) for measuring the variation of the induction in an air gap (10). The stator (1) is formed of a first stationary part and a second part (2) which is either stationary or mobile, the two parts defining between them a main air gap (5) in which the part of the mobile element moves. The mobile element exhibits at least two adjacent thin parts magnetized crosswise in alternate direction, the magnetized parts being made of a material exhibiting in the entire working area a practically linear demagnetization characteristic and a reversible permeability close to that of the air. The stationary part exhibits at least two secondary air gaps (10, 11) approximately perpendicular to the main air gap (5) in which the mobile element moves. The Hall probe (12) is housed in one of the secondary air gaps (10, 11). The L/E ratio is greater than 6, L designating the width of a magnetic pole and E designating the width of main air gap (5).

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