Patent · US Expired

Friction vacuum pump

US6168374A · kind A · utility

7Cited by
10References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 5, 1999
Grant dateJan 2, 2001
Priority date
Expiry dateFeb 5, 2019

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04D19/046
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

The present invention relates to a friction vacuum pump having at least one turbomolecular pump stage (2) joined at its pressure side to a screw pump stage (4). In order to improve the pump properties it is proposed that a filling stage (3) be arranged between the turbomolecular pump stage (2) and the screw pump stage (4) that has blades (13) whose length corresponds at the suction side to the active length of the blades at the pressure side of the turbomolecular pump stage (2), and at the pressure side to the depth of the suction-side region of the screw (14) of the screw stage (4).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.