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:
Jul. 06, 2004
Filed:
Sep. 30, 2002
Hartmut Kriehn, Köln, DE;
Lothar Brenner, Bad Münstereifel, DE;
Leybold Vakuum GmbH, Cologne, DE;
Abstract
A screw vacuum pump ( ) has shafts ( ) and rotors ( ) secured to the shafts. Each rotor has a central hollow chamber ( ) which receives the shaft or contains in built-in components rotating along with the rotor to define a relatively thin annular slot segment ( ) for cross-flow circulation of coolant. The annular slot segment is disposed between the built-in components and an inner wall of the rotor's hollow chamber and between a suction side and a delivery side of the rotor. Separate feed and discharge lines ( ) circulate the coolant through the annular slot segment in such a way that the coolant remains cavitation-free and bubble-free.