Patent · US Expired

Multiple stage cryogenic pump and method of pumping

US4148196A · kind A · utility

22Cited by
5References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 1977
Grant dateApr 10, 1979
Priority date
Expiry dateApr 25, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S55/15
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A multiple stage cryogenic vacuum pump is disclosed for transferring matter or species between a gas and a vacuum chamber. The vacuum chamber has an orifice through which the matter or species moves and through which some of the gas leaks into the chamber. The chamber also has an interior surface which is spaced from the path of movement of the matter or species and encircles such path, and an internal divider extending to a position adjacent the interior surface and dividing the chamber into a first region adjacent the orifice and a second region downstream from the first region, with the interior surface extending in both regions. The surface is cooled by a single refrigerating device to below the condensation temperature of the gas, to produce a pressure below atmospheric in the first region and a lower pressure in the second region. The divider contains an aperture through which the matter or species travels and may itself be cooled to precool gas contacting it. The matter or species may be ions or may be a strip of material to be treated. In the latter case the gas which is cryopumped can be warmed and flowed countercurrent to the strip to precondition the strip prior to its e…

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