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. 14, 2009
Filed:
May. 23, 2003
Applicants:
Rudolf Bahnen, Roetgen, DE;
Josef Hodapp, Köln, DE;
Karl-heinz Ronthaler, Zülpich, DE;
Inventors:
Assignee:
Oerlikon Leybold Vacuum GmbH, Cologne, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B 17/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A two-shaft vacuum pump has a simplified drive motor. The two-shaft vacuum pump has a synchronous motor as a drive motor which motor rotor is permanently excited. Permanently excited motor rotors are sufficiently small and of light weight such that rotor supporting bearings can be omitted. This also eliminates the problems associated with cooling and lubrication of the supporting bearings.