Patent · US Expired

Detecting and processing circuitry for magnetostriction type torque sensor

US5419207A · kind A · utility

31Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 28, 1993
Grant dateMay 30, 1995
Priority date
Expiry dateMay 28, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01L3/105
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A detection and processing circuitry of a magnetostriction type torque sensor is disclosed. An alternating current voltage signal Vo is generated and output from an oscillator. A shift circuit shifts a phase of the AC voltage waveform of the oscillator by 1/4 period and outputs the phase shifted voltage to a detector. The detector modulates the inverted voltage signal Va on the basis of the phase shifted voltage signal and an integrator integrates the detector output voltage in a time range from (.alpha.-.pi./2) to (.alpha.-3.pi./2). Thus, the output voltage signal Vd from the integrator indicates a resistance value of an imaginary part, i.e., inductance of the impedance of the detection coil of a magnetostrictive shaft of the torque sensor which is not dependent on the change in a temperature.

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