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:
Jan. 26, 1982
Filed:
May. 21, 1979
Applicant:
Inventor:
Akira Yamamura, Framingham, MA (US);
Assignee:
Cambridge Thermionic Corporation, Cambridge, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F04B / ; F16C / ;
U.S. Cl.
CPC ...
417424 ; 308 10 ;
Abstract
A turbomolecular vacuum pump utilizes a virtually zero power magnetic bearing assembly with a single axis sevo control and has an optimized L/D ratio and an optimized number of pole faces. In such a structure, radial stiffness is low and radial damping is high so that single axis control is possible. A frusto-conical mechanical bearing structure is shown as a fail-safe back-up for the magnetic suspension system taught.