Cryopump

US4479360A · kind A · utility

Assignee

• Leybold-Heraeus GmbH · DE

Inventors

• Werner B/a/ chler · Rösrath, DE
• Rolf Heisig · Weilerswist, DE

Key dates

• Filing date: Dec 6, 1982
• Grant date: Oct 30, 1984
• Expiry date: Dec 6, 2002

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S417/901
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A cryopump having two refrigerator stages operable for producing progressively lower temperatures and at least one surface between the refrigerator stages and in such thermal communication therewith as to have, during operation of the refrigerator stages, temperatures which adsorb and desorb thereon at least one gas in the cryopump, having the improvement comprising: PA0 shield means extending over substantially all of the surface for substantially preventing the gas from circulating to the surface; and PA0 means for maintaining the shield means at a substantially constant temperature during operation of the refrigerator stages.