Patent · US Expired

Leak rate measuring device

US7331216B2 · kind B2 · utility

0Cited by

3References

6Claims

0Family size

Assignee

INFICON AG · LI

Inventors

Ludolf Gerdau · Cologne, DE
Randolf Rolff · Horrem, DE
Ralf Kilian

Key dates

Filing date	May 10, 2004
Grant date	Feb 19, 2008
Priority date	—
Expiry date	Jun 29, 2024

Classification

Technology area (CPC G)Physics
CPC primaryG01M3/202
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

A leak rate measuring device contains a strip spectrometer in which the ion path of the respective gas is influenced by at least one variable influencing quantity. When a gas having a predetermined mass is detected, and leakages of a gas having other predetermined masses interfere with this detection due to lack of selectivity of the spectrometer, the influencing quantity is modulated in a sinusoidal manner, and the wanted signal is subsequently selected in a lock-in amplifier. This modulation enables, for example, the elimination of the interfering influence of underground water during the leak rate measurement while using helium as a test gas.

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