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:
Oct. 28, 2003
Filed:
Nov. 13, 2001
Applicant:
Inventors:
Armin Conrad, Herborn, DE;
Heinrich Lotz, Wetzlar, DE;
Assignee:
Pfeiffer Vacuum GmbH, Asslar, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04D 1/904 ;
U.S. Cl.
CPC ...
F04D 1/904 ;
Abstract
A gas friction pump including a housing ( ) having a suction opening ( ) and a gas outlet opening ( ), rotor ( ) and stator ( ) components arranged in the housing ( ) for delivery of gases and for obtaining a pressure ratio; and an additional, at least one-stage, concave pump unit ( ) provided at a side of the suction opening ( ) and having a gas delivery structure, with the additional pump unit ( ) being so formed that gas delivery takes place in a radial direction, and with rotor components ( ) of the additional pump unit ( ) being supported on the same rotor shaft ( ) as the rotor components of the pump itself.