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US3728868A Expired / Lapsed US ⏱️ 0.0 years remaining

Cryogenic refrigeration system

Assignee: Sumitomo SHI Cryogenics of America Inc
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Filing: 1971-12-06
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Granted: 1973-04-24
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Expires: 1991-12-06
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Abstract

Abstract A cryogenic refrigeration system wherein in a heat exchanger normally disposed in a container and having a Joule-Thompson orifice provided in one end of the heat exchanger to promote liquefaction of a working fluid by expansion, there is included means to control the flow of fluid through the orifice. The refrigeration system is characterized in that flow through the orifice is regulated by a valve which is activated by a temperature sensing fluid filled bulb-activating means combination spaced apart from the orifice toward the warm end of the heat exchanger.

Inventors

  • 👤 R Longsworth

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 14:22
CPC Classifications
F; F25; F25J; F25J1/00; F25J1/02; F25J1/0243; F25J1/0257; F25J1/0275; F25J1/0276; F25B; F25B9/00; F25B9/02; F25B2309/00; F25B2309/02; F25B2309/022; F25J2290/00; F25J2290/42

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 164 words
In a cryogenic refrigeration system of the type wherein a working fluid is expanded through an orifice in a heat exchanger, disposed about a mandrel having a warm end and a cold end, normally disposed in a container to produce an inventory of liquid at the cold end in the container adjacent the orifice the improvement which comprises: a valve member disposed adjacent said orifice to control the fluid flow therethrough; means for moving said valve in relation to said orifice said means including a fixed fluid filled sensing bulb having low thermal mass and high heat transfer capacity and movable actuating means in fluid communication with said bulb responsive to changes in the volume of fluid in said sensing bulb and actuating means, said sensing bulb and actuating means spaced apart from said orifice and located between said orifice and said warm end of said heat exchanger; whereby said bulb and actuating means react to provide smooth controlled fluid flow through said orifice.
Claim 2
Dependent Claim 164 words
In a cryogenic refrigeration system of the type wherein a working fluid is expanded through an orifice in a heat exchanger, disposed about a mandrel having a warm end and a cold end, normally disposed in a container to produce an inventory of liquid at the cold end in the container adjacent the orifice the improvement which comprises: a valve member disposed adjacent said orifice to control the fluid flow therethrough; means for moving said valve in relation to said orifice said means including a fixed fluid filled sensing bulb having low thermal mass and high heat transfer capacity and movable actuating means in fluid communication with said bulb responsive to changes in the volume of fluid in said sensing bulb and actuating means, said sensing bulb and actuating means spaced apart from said orifice and located between said orifice and said warm end of said heat exchanger; whereby said bulb and actuating means react to provide smooth controlled fluid flow through said orifice.
Claim 3
Dependent Claim 15 words
A refrigeration system according to claim 1 wherein said actuating means is a flexible bellows.
Claim 4
Dependent Claim 33 words
A refrigeration system according to claim 1 wherein the sensing bulb is located between 5 and 30 percent of the distance from the cold end toward the warm end of the heat exchanger.
Claim 5
Dependent Claim 26 words
A refrigeration system according to claim 1 wherein the actuating means moves the total distance of between 0.003 and 0.006 inches to achieve total flow control.
Claim 6
Dependent Claim 22 words
A refrigeration system according to claim 1 wherein said sensing bulb is a tube having a wall thickness of about 0.003 inches.
Claim 7
Dependent Claim 42 words
A refrigeration system according to claim 1 wherein the fluid in the sensing bulb actuates means is nitrogen gas and the valve is set so that at operating pressures of about 300 psi the temperature of the nitrogen is about 140* K.
Claim 8
Dependent Claim 27 words
A refrigeration system according to claim 1 wherein the actuating means is spaced apart from said sensing means and in fluid communication therewith by a capillary tube.
Claim 9
Dependent Claim 19 words
A refrigeration system according to claim 1 wherein said sensing means and said actuating means are inside said mandrel.

References Cited (Backward Citations)

US3590597A Cited
US3630047A Cited
US3640091A Cited
US3691784A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-04-23 1976-10-23 1977-04-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-04-23 1980-10-23 1981-04-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-04-23 1984-10-23 1985-04-24 $7700.00 Window Closed / Lapsed

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