Patent · US Expired

Variable frequency inductive proximity sensor

US5508662A · kind A · utility

10Cited by
2References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 4, 1995
Grant dateApr 16, 1996
Priority date
Expiry dateApr 4, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V3/102
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A proximity sensor includes a coil for sensing metal objects which are part of an oscillatory circuit and an oscillator which drives the oscillatory circuit at a constant frequency. A tuning device is connected in parallel with the oscillatory circuit. The tuning device is a variable gain amplifier with feedback via an inductive or capacitive impedance.

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