US3769806A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for cryopumping gas
Assignee: PROCEDES GEORGES CLAUDE SA
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Filing: 1971-11-12
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Granted: 1973-11-06
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Expires: 1991-11-12
Abstract
Abstract This invention relates to a method of and apparatus for pumping gas and particularly to a system in which a primary vacuum of the order of 10 1 to 10 4 Torr approximately is produced, followed by the production of a secondary vacuum. According to the invention, the main trapping surface effected in a main cryopumping operation is arranged in two areas, one being of easy access to the gas to be pumped and the other more difficult of access. A cryodeposit of the adsorbing gas is positioned practically exclusively in the area of most difficult access, in order to adsorb the residual gases. The most important residual gas referred to is helium.
Inventors
- 👤 J Boissin
- 👤 J Thibault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:24
CPC Classifications
F; F04; F04B; F04B37/00; F04B37/06; F04B37/08; H; H01; H01J; H01J9/00; H01J9/38
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
117 words
A method of cryopumping gases, comprising producing in a gas a primary vacuum of the order of 101 to 104 Torr, and producing a secondary vacuum in said gas by thereafter cryopumping the gas on a refrigerated trapping wall means, said trapping wall means having portions that are so positioned as to be successively contacted by said gas with a first portion of said trapping wall means contacted by said gas prior to a second portion of said trapping wall means, and applying to only said second portion of said trapping wall means a series of layers of adsorbing gas in solid phase thereby to promote the deposition of gas to be pumped on each said layer.
Claim 2
Independent Claim
117 words
A method of cryopumping gases, comprising producing in a gas a primary vacuum of the order of 101 to 104 Torr, and producing a secondary vacuum in said gas by thereafter cryopumping the gas on a refrigerated trapping wall means, said trapping wall means having portions that are so positioned as to be successively contacted by said gas with a first portion of said trapping wall means contacted by said gas prior to a second portion of said trapping wall means, and applying to only said second portion of said trapping wall means a series of layers of adsorbing gas in solid phase thereby to promote the deposition of gas to be pumped on each said layer.
Claim 3
Dependent Claim
15 words
A method as claimed in claim 1, and producing said primary vacuum by sorption pumping.
Claim 4
Dependent Claim
36 words
A method as claimed in claim 1, in which said adsorbing gas is a member selected from the group consisting of argon, CO2, H2O, N2O, N2 and SF6 and said gas to be pumped is helium.
Claim 5
Dependent Claim
163 words
Cryopumping apparatus comprising a sorption pump (103), a cryopump (104) communicating with said sorption pump, said cryopump comprising a pumping chamber (105), a pumping body disposed inside and spaced from the side walls of said pumping chamber and providing a main trapping wall (108), means (109) for cooling said pumping body to very low temperature, means defining a heat screen at a relatively low temperature above and at a distance from said trapping wall, the last-named means comprising an inner wall (107) of said chamber of said cyopump and reflector baffle means (114) permeable to gases, said chamber having a pumping opening (200) for the admission of gas to be pumped, said trapping wall having a portion (108b, 108d) relatively close to said pumping opening and a portion (108'') relatively remote from said opening, and means to direct an absorbing gas against said relatively remote portion to form a solid cryodeposit to promote the adsorption of gas to be pumped on said cryodeposit.
Claim 6
Dependent Claim
163 words
Cryopumping apparatus comprising a sorption pump (103), a cryopump (104) communicating with said sorption pump, said cryopump comprising a pumping chamber (105), a pumping body disposed inside and spaced from the side walls of said pumping chamber and providing a main trapping wall (108), means (109) for cooling said pumping body to very low temperature, means defining a heat screen at a relatively low temperature above and at a distance from said trapping wall, the last-named means comprising an inner wall (107) of said chamber of said cyopump and reflector baffle means (114) permeable to gases, said chamber having a pumping opening (200) for the admission of gas to be pumped, said trapping wall having a portion (108b, 108d) relatively close to said pumping opening and a portion (108'') relatively remote from said opening, and means to direct an absorbing gas against said relatively remote portion to form a solid cryodeposit to promote the adsorption of gas to be pumped on said cryodeposit.
Claim 7
Dependent Claim
81 words
Apparatus as claimed in claim 4, said trapping wall means comprising a receptacle (203) for a liquid at very low temperature and a collar (201) spaced from and surrounding said receptacle, said collar being secured to the bottom (202) of said receptacle by means of a wall (207), said wall and collar and receptacle defining an annular chamber that opens toward said opening (200), said directing means (205) being disposed on the side of said bottom (202) opposite said opening (200).
Claim 8
Dependent Claim
14 words
Apparatus as claimed in claim 5, and a collar (206) surrounding said directing means.
Claim 9
Dependent Claim
25 words
Apparatus as claimed In claim 4, said directing means (17) having a plurality of outlets to direct said absorbing gas in a plurality of streams.
Claim 10
Dependent Claim
35 words
Apparatus as claimed in claim 7, said heating means comprising a mass of thermally conductive element (130) disposed in said conduit (131) and having an extension (130a) extending outside said chamber to a heat source.
Claim 11
Dependent Claim
31 words
Apparatus as claimed in claim 4, said directing means comprising a conduit (120) extending a substantial distance into said chamber (105), and reheating means (124) for said conduit in said chamber.
Claim 12
Dependent Claim
17 words
Apparatus as claimed in claim 9, said reheating means comprising electric resistance means disposed about said conduit.
Claim 13
Dependent Claim
46 words
Apparatus as claimed in claim 9, said conduit being connected at one end to a metering chamber (12) by means of valve means (13, 20) and a coil (14) producing a pressure drop, said conduit being connected at its other end to said directing means (17).
Claim 14
Dependent Claim
35 words
Apparatus as claimed in claim 11, said directing means having orifices (30) directed toward the surface of the cryopump which maintain the cryopump in contact with a very cold fluid when the cryopump is emptying.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |