US3834172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double-acting expander engine and cryostat
Assignee: Individual
•
Filing: 1973-11-01
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Granted: 1974-09-10
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Expires: 1993-11-01
Abstract
Abstract Double-acting expander engine minimizes shuttle losses by having a cylinder at low temperature along its entire length, minimizes pumping losses by requiring only a thin piston, and minimizes conduction losses by providing a thin piston rod. Refrigeration capacity is approximately doubled by the double-acting configuration.
Inventors
- 👤 A Dehne
- 👤 Expander Engine Double-Acting
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:03
CPC Classifications
F; F02; F02G; F02G1/00; F02G1/04; F02G1/043; F02G1/044; F02G1/0445; F25; F25B; F25B9/00; F25B9/14; F02G2244/00; F02G2244/50; F02G2250/00; F02G2250/18
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
290 words
A cryogenic refrigerator comprising: a cylinder to receive a heat load; a piston reciprocally mounted within said cylinder to divide said cylinder into a first expander space and a second expander space; a first regenerator having a warm end and a cold end, said cold end of said first regenerator being connected to said first expander space so that gas flow into and out of said first expander space flows through said first regenerator; a second regenerator having a cold end and a warm end, said cold end of said second regenerator being connected to said second expansion space so that gas flow into and out of said expander space flows through said second regenerator; means for supplying refrigerant gas at high pressure; means for supplying refrigerant gas at low pressure; valve means connected to both said refrigerant gas means and to both said regenerators for alternately supplying low pressure and high pressure refrigerant gas to said warm end of said second regenerator and for oppositely alternately supplying high pressure and low pressure refrigerant gas to said warm end of said first regenerator, the improvement comprising: said valve means being coupled to said piston to be directly actuated by piston motion; a hot cylinder having a hot end and a warm end and a displacer reciprocably mounted in said hot cylinder to displace gas between the ends thereof; a hot regenerator connected between said hot end and said warm end, said hot displacer being coupled to said piston and said valve means to move with said piston and said valve means, said warm end of said hot cylinder being connected to said valve means so that said warm end is alternately connected between said refrigerant Gas means by valve motion.
Claim 2
Dependent Claim
290 words
A cryogenic refrigerator comprising: a cylinder to receive a heat load; a piston reciprocally mounted within said cylinder to divide said cylinder into a first expander space and a second expander space; a first regenerator having a warm end and a cold end, said cold end of said first regenerator being connected to said first expander space so that gas flow into and out of said first expander space flows through said first regenerator; a second regenerator having a cold end and a warm end, said cold end of said second regenerator being connected to said second expansion space so that gas flow into and out of said expander space flows through said second regenerator; means for supplying refrigerant gas at high pressure; means for supplying refrigerant gas at low pressure; valve means connected to both said refrigerant gas means and to both said regenerators for alternately supplying low pressure and high pressure refrigerant gas to said warm end of said second regenerator and for oppositely alternately supplying high pressure and low pressure refrigerant gas to said warm end of said first regenerator, the improvement comprising: said valve means being coupled to said piston to be directly actuated by piston motion; a hot cylinder having a hot end and a warm end and a displacer reciprocably mounted in said hot cylinder to displace gas between the ends thereof; a hot regenerator connected between said hot end and said warm end, said hot displacer being coupled to said piston and said valve means to move with said piston and said valve means, said warm end of said hot cylinder being connected to said valve means so that said warm end is alternately connected between said refrigerant Gas means by valve motion.
Claim 3
Dependent Claim
30 words
The cryogenic refrigerator of claim 1 wherein said piston, said valve means, and said displacer are directly coupled together and motion thereof is influenced only by gas pressure and friction.
Claim 4
Dependent Claim
238 words
A cryogenic refrigerator comprising: a hot cylinder having a hot end and a warm end, means at the hot end of said hot cylinder for adding heat above ambient temperature to said hot cylinder, means at the warm end of said hot cylinder for rejecting heat from said warm end of said hot cylinder to the ambient; a regenerator interconnected between said hot end and said warm end of said hot cylinder; a displacer in said hot cylinder for displacing refrigerant gas through said regenerator from said hot end to said warm end of said hot cylinder upon motion of said displacer, means for moving said displacer between said hot end and said warm end of said hot cylinder; a low pressure refrigerant gas receiver at ambient temperature, a high pressure refrigerant gas receiver at ambient temperature, valve means connected to control refrigerant gas flow between the warm end of said hot cylinder and said low pressure and said high pressure receivers, said valve means being connected to be actuated by motion of said hot displacer so that gas moves from said low pressure receiver to said hot cylinder when pressure in said hot cylinder is low and gas moves from said hot cylinder to said high pressure receiver when the pressure in said hot cylinder is high; and refrigerator means connected between said high pressure and said low pressure receivers for expanding refrigerant gas to cause refrigeration.
Claim 5
Dependent Claim
238 words
A cryogenic refrigerator comprising: a hot cylinder having a hot end and a warm end, means at the hot end of said hot cylinder for adding heat above ambient temperature to said hot cylinder, means at the warm end of said hot cylinder for rejecting heat from said warm end of said hot cylinder to the ambient; a regenerator interconnected between said hot end and said warm end of said hot cylinder; a displacer in said hot cylinder for displacing refrigerant gas through said regenerator from said hot end to said warm end of said hot cylinder upon motion of said displacer, means for moving said displacer between said hot end and said warm end of said hot cylinder; a low pressure refrigerant gas receiver at ambient temperature, a high pressure refrigerant gas receiver at ambient temperature, valve means connected to control refrigerant gas flow between the warm end of said hot cylinder and said low pressure and said high pressure receivers, said valve means being connected to be actuated by motion of said hot displacer so that gas moves from said low pressure receiver to said hot cylinder when pressure in said hot cylinder is low and gas moves from said hot cylinder to said high pressure receiver when the pressure in said hot cylinder is high; and refrigerator means connected between said high pressure and said low pressure receivers for expanding refrigerant gas to cause refrigeration.
Claim 6
Dependent Claim
22 words
The cryogenic refrigerator of claim 3 wherein said means for moving said displacer in said hot cylinder is a refrigerant gas expander.
Claim 7
Dependent Claim
23 words
The cryogenic refrigerator of claim 4 wherein said expander comprises an expander cylinder and an expander piston reciprocably mounted within said expander cylinder.
Claim 8
Dependent Claim
30 words
The cryogenic refrigerator of claim 5 wherein said expander piston is directly connected to said hot cylinder displacer so that said expander piston and said hot cylinder displacer move together.
Claim 9
Dependent Claim
30 words
The cryogenic refrigerator of claim 6 wherein said expander piston is a double-acting expander piston and there is cryogenic gas expansion space on both sides of said double-acting expander piston.
Claim 10
Dependent Claim
35 words
The cryogenic refrigerator of claim 5 wherein said valve means is also connected to control refrigerant gas flow between said high pressure refrigerant gas receiver, said expander cylinder and said low pressure refrigerant gas receiver.
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) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |