Patent · US Expired

Two stage dry primary pump

US5040949A · kind A · utility

20Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 1, 1990
Grant dateAug 20, 1991
Priority date
Expiry dateJun 1, 2010

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04C2220/12
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A two stage dry primary pump comprises, in a single common stator: a screw pump at its low pressure end; and a fluid viscous effect, single rotary screw gas exhaust pump at its high pressure end; with a link duct providing communication between the screw pump and the viscous effect, single rotary screw gas exhaust pump. The invention is applicable to vacuum pumps.

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