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:
Dec. 21, 2004
Filed:
Oct. 22, 2002
BOC Edwards Technologies Limited, Narashino, JP;
Abstract
A molecular pump for exhausting a chamber has a casing, a stator mounted in the casing, and a rotor mounted in the casing for undergoing rotation relative to the stator during exhaustion of the container. The rotor has a surface disposed opposite to and confronting a surface of the stator. A thread groove is formed in at least one of the opposite and confronting surfaces of the stator and the rotor. A clearance varying device varies a magnitude of a clearance between the opposite and confronting surfaces of the stator and the rotor. An exhaust controlling device controls a degree of exhaustion of the chamber by adjusting the magnitude of the clearance between the opposite and confronting surfaces of the stator and the rotor to a preselected target value during operation of the molecular pump.