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:
Jun. 22, 1999
Filed:
Feb. 13, 1997
Applicant:
Inventor:
Graeme Huntley, Crawley, GB;
Assignee:
The BOC Group plc, Windlesham, GB;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B / ;
U.S. Cl.
CPC ...
417152 ;
Abstract
A diffusion pump for evacuating a chamber is provided with a hollow outer body including an outlet for connection to a backing pump and a base for containing a working fluid. A vapor chimney extends from the base within the hollow outer body and includes at least two spaced apart jet stages. The working fluid is heated when present in said base. Two or more inlets are formed in the hollow outer body for communicating with said at least one chamber to be evacuated. The presence of the two inlets provides the possibility of differential pumping.