US4484458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for condensing liquid cryogen boil-off
Assignee: Sumitomo SHI Cryogenics of America Inc
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Filing: 1983-11-09
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Granted: 1984-11-27
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Expires: 2003-11-09
Abstract
Abstract An apparatus for condensing cryogen (e.g., helium) boil-off in a confined space such as the neck tube of a helium cryostat comprising a Joule-Thompson heat exchanger and valve disposed around a displacer-expander cryogenic refrigerator so the thermal gradient in the heat exchanger matches that of the refrigerator.
Inventors
- 👤 Ralph C. Longsworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:59
CPC Classifications
F; F25; F25J; F25J1/00; F25J1/02; F25J1/0243; F25J1/0257; F25J1/0275; F25J1/0276; F25B; F25B9/00; F25B9/02; F25B2400/00; F25B2400/17; F25J2290/00; F25J2290/42; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/888; Y10S505/894; Y10S505/895
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
132 words
An apparatus for condensing liquid cryogen boil-off in a confined space comprising in combination: a multi-stage displacer-expander refrigerator with each stage of said refrigerator containing a heat station, said refrigerator having a coldest stage capable of being cooled to between 15° and 20° K.; a helium recondenser disposed axially and spaced apart from the coldest stage of said refrigerator; a Joule-Thompson heat exchanger coiled around said refrigerator and in thermal contact with each of said heat stations, said heat exchanger constructed and arranged to conduct high pressure helium to a Joule-Thompson valve disposed upstream of said helium recondenser and return low pressure helium, said Joule-Thompson heat exchanger adapted to approximately match thermal gradients in said refrigerator and in the stratified helium between the coldest stage of said refrigerator and said helium condenser.
Claim 2
Independent Claim
132 words
An apparatus for condensing liquid cryogen boil-off in a confined space comprising in combination: a multi-stage displacer-expander refrigerator with each stage of said refrigerator containing a heat station, said refrigerator having a coldest stage capable of being cooled to between 15° and 20° K.; a helium recondenser disposed axially and spaced apart from the coldest stage of said refrigerator; a Joule-Thompson heat exchanger coiled around said refrigerator and in thermal contact with each of said heat stations, said heat exchanger constructed and arranged to conduct high pressure helium to a Joule-Thompson valve disposed upstream of said helium recondenser and return low pressure helium, said Joule-Thompson heat exchanger adapted to approximately match thermal gradients in said refrigerator and in the stratified helium between the coldest stage of said refrigerator and said helium condenser.
Claim 3
Dependent Claim
29 words
An apparatus according to claim 1 wherein said Joule-Thompson heat exchanger consists of a high pressure cryogen tube disposed within a larger diameter, low pressure multi channel cryogen tube.
Claim 4
Dependent Claim
16 words
An apparatus according to claim 1 wherein the heat exchanger is a tube within a tube.
Claim 5
Dependent Claim
17 words
An apparatus according to claim 1 wherein there is included an adsorber upstream of said Joule-Thompson valve.
Claim 6
Dependent Claim
39 words
An apparatus according to claim 1 wherein said heat exchanger includes at least one continuous low pressure return path from the vicinity of the helium condenser normally at 4.2° Kelvin to a location on the apparatus at ambient temperature.
Claim 7
Dependent Claim
38 words
An apparatus according to claim 1 wherein said heat exchanger includes at least one continuous high pressure path from the vicinity of the helium condenser normally at 4.2° Kelvin to a location on the apparatus at ambient temperature.
Claim 8
Dependent Claim
16 words
An apparatus according to claim 1 wherein said heat exchanger is removably fastened to said refrigerator.
Claim 9
Dependent Claim
16 words
An apparatus according to claim 1 wherein said helium recondenser includes a finned tube heat exchanger.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-27 | 1988-05-28 | 1988-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-27 | 1992-05-28 | 1992-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-27 | 1996-05-28 | 1996-11-27 | $7700.00 | Window Closed / Lapsed |