Patent · US Expired

Digital differential pressure transducer

US4382385A · kind A · utility

23Cited by
9References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 17, 1980
Grant dateMay 10, 1983
Priority date
Expiry dateApr 17, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01L9/0022
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A digital differential pressure transducer with relatively low sensitivity to common mode line pressure errors. The transducer includes an airtight enclosure having a pair of pressure ports through which pressure is coupled to opposite sides of a pressure-sensing diaphragm or bellows. The force generated by the pressure differential across the diaphragm or bellows is coupled to a stress-sensitive resonator either directly or through a force-transmitting structure. A first bellows extends from the diaphragm or a bellows end cap. The first bellows has an effective area which is substantially smaller than the effective area of the pressure-sensing diaphragm or bellows so that it applies substantially less pressure-induced stress to the resonator than does the pressure-sensing diaphragm or bellows. A second bellows has an effective area and a mounting position chosen to counteract the effect of the first bellows on the pressure-sensing diaphragm or bellows. The common mode line pressure error of the transducer resulting from a mismatch between the forces generated by the first and second bellows is thus proportional to the ratio of the effective area of the first bellows to the effecti…

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