Patent · US Expired

Capacitive position sensor including a scale with integral topographical features which effect the mutual capacitance between cursor electrodes

US5394096A · kind A · utility

34Cited by
8References
24Claims
0Family size

Inventor

Key dates

Filing dateNov 16, 1993
Grant dateFeb 28, 1995
Priority date—
Expiry dateNov 16, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D5/2415
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A capacitive position sensor has a scale (10), having hollow or raised topographical features, and a cursor (20) having an electrode array comprising at least two transmitting electrodes (21a, 21b) and at least one receiving electrode (21c) separated by shielding electrodes (21g). The coupling capacitances (Cac, Cbc) between transmitting and receiving cursor (20) electrodes are modified as a function of the position (x) of the scale topographic feature (11) relative to the cursor, the evaluation of the variation of the signals picked up by the receiving electrode permitting a precise measurement of the relative displacement between scale and cursor.

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