Patent · US Expired

Temperature compensation in differential pressure leak detection

US4947352A · kind A · utility

19Cited by
3References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 25, 1988
Grant dateAug 7, 1990
Priority date
Expiry dateMar 25, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01M3/26
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A microprocessor is employed to control a test program which operates to cause a component under test to be filled (or evacuated) to a predetermined pressure P.sub.2 at which a leak test is to be carried out. The test program is arranged firstly to perform a rapid test at atmospheric pressure P.sub.1 to determine the pressure change dpl'/dt in the component due to the temperature fluctuation. The component is then filled (or evacuated) automatically to the test pressure P.sub.T, at which the leak check is carried out. Temperature compensation is achieved by subtracting the value of C dpl'/dt from the pressure change dp.sub.t /dt actually measured, i.e. the actual leak rate dPL/dt is given by ##EQU1## where the constant, C, is generated from an identical proram run, the calibration run, on a known non-leaker with a high temperature fluctuation.

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