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US4302945A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for defrosting a refrigeration system

Assignee: Carrier Corp
•
Filing: 1980-10-02
•
Granted: 1981-12-01
•
Expires: 2000-10-02
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Abstract

Abstract Apparatus and a method for operating a refrigeration system without reverse cycle defrost are disclosed. A heat exchanger is divided into a plurality of zones, one zone being constantly utilized as a subcooler to both defrost said zone and to subcool the refrigerant. The remaining zones of the heat exchanger are utilized as an evaporator as is known in the art. A selector valve which is capable of indexing liquid refrigerant flow between zones and receiving gaseous refrigerant from the remaining zones is also disclosed. Additionally, a header arrangement having both expansion means and a conduit controlled by check valve is utilized to direct refrigerant flow from the subcooled zones to the remaining zones of the heat exchanger which act as an evaporator.

Inventors

  • 👤 William W. Bell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 19:53
CPC Classifications
F; F25; F25B; F25B39/00; F25B39/02; F25B39/028; F25B47/00; F25B47/02; F25B47/022

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 160 words
A method of operating a refrigeration system having a heat exchanger upon which frost may accumulate which comprises the steps of: compressing gaseous refrigerant to increase the temperature and pressure of the refrigerant condensing said refrigerant to a liquid to reject the heat of condensation dividing the heat exchanger into a plurality of zones, each zone acting as a separate heat transfer unit subcooling the liquid refrigerant in at least one zone of the heat exchanger such that heat energy is rejected from the refrigerant to melt the frost accumulated on that zone of the heat exchanger evaporating the subcooled liquid refrigerant in the remaining zones of the outdoor heat exchanger to absorb heat energy from the ambient air in heat exchange relation therewith, and cycling the steps of subcooling and evaporating such that each zone of the evaporator periodically acts as a subcooler for the purpose of melting the frost accumulated on the heat exchange surfaces of that zone.
Claim 2
Independent Claim 160 words
A method of operating a refrigeration system having a heat exchanger upon which frost may accumulate which comprises the steps of: compressing gaseous refrigerant to increase the temperature and pressure of the refrigerant condensing said refrigerant to a liquid to reject the heat of condensation dividing the heat exchanger into a plurality of zones, each zone acting as a separate heat transfer unit subcooling the liquid refrigerant in at least one zone of the heat exchanger such that heat energy is rejected from the refrigerant to melt the frost accumulated on that zone of the heat exchanger evaporating the subcooled liquid refrigerant in the remaining zones of the outdoor heat exchanger to absorb heat energy from the ambient air in heat exchange relation therewith, and cycling the steps of subcooling and evaporating such that each zone of the evaporator periodically acts as a subcooler for the purpose of melting the frost accumulated on the heat exchange surfaces of that zone.
Claim 3
Dependent Claim 35 words
The method as set forth in claim 1 and further including after the step of subcooling the step of expanding the liquid refrigerant such that the step of evaporating may occur at lower refrigerant pressures.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-30 1985-06-01 1985-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-30 1989-06-01 1989-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-30 1993-06-01 1993-12-01 $7700.00 Window Closed / Lapsed

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