US3769808A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refrigeration systems with elevated receivers
Assignee: Ardco Inc
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Filing: 1972-01-24
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Granted: 1973-11-06
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Expires: 1992-01-24
Abstract
Abstract In air cooled refrigeration systems of the compression type which may operate in low ambients with no or minimum condenser capacity control, it is sometimes required to locate the evaporator high above the condensing unit. Especially under winter conditions, it is likely that liquid refrigerant leaving the condensing unit will suffer sufficient pressure loss by gravity in traversing the vertical upflow riser, that its flash point will be reached. Then the formerly clear liquid column will flash into a mixture of vapor and liquid. Most expansion devices are designed to function correctly with vapor-free liquid entering their orifices.
Inventors
- 👤 D Kramer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:16
CPC Classifications
F; F25; F25B; F25B41/00; F25B41/30; F25B49/00; F25B49/02; F25B49/025; F25B2500/00; F25B2500/01; Y; Y10; Y10S; Y10S62/00; Y10S62/17
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
73 words
In an air-cooled refrigeration system comprising conduitconnected compressor, condenser means, receiver means, evaporator, and an expansion device located over the condenser means, the improvement which comprises said receiver means being located at an elevation substantially higher than said condenser means whereby upon a decrease in ambient temperature at said condenser means, with resulting decrease in head pressure, said expansion device is continuously supplied with substantially bubble-free refrigerant liquid during operation of said system.
Claim 2
Dependent Claim
73 words
In an air-cooled refrigeration system comprising conduitconnected compressor, condenser means, receiver means, evaporator, and an expansion device located over the condenser means, the improvement which comprises said receiver means being located at an elevation substantially higher than said condenser means whereby upon a decrease in ambient temperature at said condenser means, with resulting decrease in head pressure, said expansion device is continuously supplied with substantially bubble-free refrigerant liquid during operation of said system.
Claim 3
Dependent Claim
35 words
A refrigeration system as in claim 1 which includes a check valve in the conduit connecting the condenser and the receiver oriented to allow flow from the condenser to the receiver and prevent reverse flow.
Claim 4
Dependent Claim
22 words
A refrigeration system as in claim 2 which includes a solenoid valve in the conduit connecting the receiver with the expansion device.
Claim 5
Independent Claim
78 words
The method of ensuring, during operating cycles, a supply of bubble-free liquid refrigerant to the expansion device of an air-cooled compression-type refrigeration system comprising conduit-connected compressor; condenser and receiver intended for year-round outdoor use; an expansion device elevated over the condenser, and evaporator, said method comprising the step of elevating the receiver over the condenser to a level near that of the expansion device and permitting substantially free variation of head pressure with ambient temperature at the condenser.
Claim 6
Independent Claim
78 words
The method of ensuring, during operating cycles, a supply of bubble-free liquid refrigerant to the expansion device of an air-cooled compression-type refrigeration system comprising conduit-connected compressor; condenser and receiver intended for year-round outdoor use; an expansion device elevated over the condenser, and evaporator, said method comprising the step of elevating the receiver over the condenser to a level near that of the expansion device and permitting substantially free variation of head pressure with ambient temperature at the condenser.
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 |