Patent · US Expired

Capacitance type displacement measuring instrument

US4733235A · kind A · utility

13Cited by
12References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 26, 1984
Grant dateMar 22, 1988
Priority date
Expiry dateOct 26, 2004

Classification

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

Abstract

A capacitance type displacement measuring instrument is disclosed in which a change in electric capacity between electrodes due to a change in displacement between two members movable relative to each other is detected on the basis of a change in phase of a detection signal and a displacement value between the two members is measured from the change in the capacity. AC signals are successively applied to transmitting electrodes provided on one of the members at a predetermined pitch by a multiplexer and signals induced in transfer electrodes at a predetermined pitch differing from the aforesaid pitch of the transmitting electrodes are received by pickup electrodes provided on the aforesaid one of the members. The relative displacement is detected from a change in phase of a received signal of substantially triangular waveform, which are obtained by the pickup electrode.

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