Patent · US Expired

Capacitance bar sensor

US4947131A · kind A · utility

11Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 21, 1989
Grant dateAug 7, 1990
Priority date
Expiry dateApr 21, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B7/08
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A capacitance sensor for measuring thickness variations in film materials, having a sensor mounted in a housing plate slot, with an air gap between the sensor and the housing plate, the sensor being affixed to an insulator support plate, the insulator support plate being affixed to the housing plate, with a bottom plate affixed against the lower side of the housing plate, having enlarged openings for permitting the passage of a conductor to the sensor; all of the conductor and insulator materials having a coefficient of linear temperature expansion of less than 1.times.10.sup.-6 per degree centrigrade, the insulator materials having virtually no dialectic variation with temperature.

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