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:
Apr. 10, 2012
Filed:
Dec. 24, 2008
John C. Helmer, Eugene, OR (US);
Silvio Giors, Turin, IT;
John C. Helmer, Eugene, OR (US);
Silvio Giors, Turin, IT;
Agilent Technologies, Inc., Santa Clara, CA (US);
Abstract
A molecular spiral-type vacuum pumping stage comprises a rotor disk having smooth surfaces cooperating with a stator. The stator is provided with a plurality of spiral channels at least on the surface facing the rotor disk, wherein the gas to be pumped flows in centripetal direction. The cross-section area (σ) of the channels is reduced from the center towards the outer periphery of the stator. Due to this arrangement, it is possible to avoid the reduction of the internal gas flow velocity along the pumping stage and the related risk of internal compression or re-expansions, this limiting the power losses. The present invention also refers to a vacuum pump comprising at least one pumping stage as described above.