The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 1994
Filed:
Sep. 23, 1992
Gilles Baret, Annecy, FR;
Roland Gevaud, Pringy, FR;
Alcatel Cit, Paris, FR;
Abstract
A helium leak detector includes a gas analyzer and a secondary pump having at least on its discharge side a Holweck type stage. The pump is of a type enabling the suction pressure to be reduced to a value at least equal to 10.sup.-4 mbar and a discharge pressure which is sufficiently high to be compatible with the suction pressure of a dry primary pump having at least two stages. The secondary pump is connected to the low-pressure output of a sampling unit on an intermediate point of the secondary pump where the flow conditions are molecular. A sniffer probe is connected to the high-pressure side of the sampling unit. This high-pressure side is further connected to the dry primary pump between its at least two stages.