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. 20, 1998
Filed:
Dec. 19, 1996
Marsbed Hablanian, Wellesley, MA (US);
Varian Associates, Inc., Palo Alto, CA (US);
Abstract
A molecular drag compressor includes a rotor disk and a stator that defines a tangential flow channel having an inlet and an outlet. A stationary baffle is disposed in the tangential flow channel adjacent to the outlet. The baffle is spaced from the rotor disk by a gap. A surface of the baffle facing the rotor disk has surface irregularities including peaks for defining the gap and valleys between the peaks for accumulation of particles. The surface irregularities may form a series of grooves. The molecular drag compressor is preferably utilized in a high vacuum pump which includes an axial turbomolecular compressor and a molecular drag compressor. Additional features which limit the effect of particulate accumulation in molecular drag compressors are disclosed.