Patent · US Expired

Leak test method and apparatus

US6182501A · kind A · utility

41Cited by
7References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 1998
Grant dateFeb 6, 2001
Priority date
Expiry dateOct 15, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01M3/3263
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a leak test method and apparatus which introduces high-pressure gas into a work and a master from a high-pressure gas source through first and second electromagnetic valves, respectively, closes the first and second electromagnetic valves, detects the pressure difference between the work and the master by a differential pressure sensor, and compares the amount of leakage, obtained from the pressure difference, with a leakage reference value to thereby decides the work to be leak-free or leaky, a third electromagnetic valve is provided which permits and inhibits the passage of gas between the work and the master. Prior to measuring pressure difference variations in a measurement period and a stabilization period, the third electromagnetic valve is opened to establish a pressure equilibrium between the work and the master, then the electromagnetic valve is closed, then measures the pressure difference variations, and a last pressure difference variation .delta.p.sub.e is subtracted from an initial pressure difference variation .delta.p.sub.s to obtain the amount of drift.

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