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. 12, 2005
Filed:
May. 05, 2003
Applicants:
Roberto Cerruti, Turin, IT;
Silvio Giors, Turin, IT;
Inventors:
Roberto Cerruti, Turin, IT;
Silvio Giors, Turin, IT;
Assignee:
Varian, S.p.A., Turin, IT;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F04D005/00 ; F04D019/04 ;
U.S. Cl.
CPC ...
Abstract
A pumping stage for a vacuum pump, has an improved geometry allowing an optimum trade-off to be achieved between the exhaust pressure and the pumping rate attained in that stage. In the pumping stage () the axial extension that is the height of the pumping channel () varies along the circumference of the channel () between the inlet port () and the outlet port ().