United States Patent
US Patent 4596123: Frost-resistant year-round heat pump
US 4596123 ยท granted 1986-06-24
Abstract
This invention is an improved refrigerant-cycle heat pump that requires neither a defrosting means nor a backup heat source. From widely varying outside environments, it pumps heat to heat living spaces or domestic hot water. Liquid refrigerant flows from a receiver through expansion valves into an outside evaporator consisting of a segmented array of plates where heat is absorbed from the atmosphere to evaporate the refrigerant. The resultant gas is compressed by a motor-driven compressor, gives up heat in a condenser, becomes liquid, and returns to the receiver. The segmented evaporator enables the self-governing heat pump system to choose the proper magnitude of evaporator area, in response to its determination of compressor suction pressure or motor power demand, so as to provide a steady refrigerant flow to the compressor and thereby maintain optimum heat pumping despite extreme excursions of outside temperature. The configuration of evaporator segments as plates enables the system to operate without interruption or performance deterioration even though frost or ice forms on plate surfaces.
| Patent Number | 4596123 |
|---|---|
| Title | Frost-resistant year-round heat pump |
| Filed | 1984-01-09 |
| Granted | 1986-06-24 |
| Inventor(s) | Cooperman; Curtis L. |
| Number of Claims | 43 |
Abstract
This invention is an improved refrigerant-cycle heat pump that requires neither a defrosting means nor a backup heat source. From widely varying outside environments, it pumps heat to heat living spaces or domestic hot water. Liquid refrigerant flows from a receiver through expansion valves into an outside evaporator consisting of a segmented array of plates where heat is absorbed from the atmosphere to evaporate the refrigerant. The resultant gas is compressed by a motor-driven compressor, gives up heat in a condenser, becomes liquid, and returns to the receiver. The segmented evaporator enables the self-governing heat pump system to choose the proper magnitude of evaporator area, in response to its determination of compressor suction pressure or motor power demand, so as to provide a steady refrigerant flow to the compressor and thereby maintain optimum heat pumping despite extreme excursions of outside temperature. The configuration of evaporator segments as plates enables the system to operate without interruption or performance deterioration even though frost or ice forms on plate surfaces.
Claim 1
A heat pump system comprising a refrigerant, expansion valve means, an evaporator, a condenser and a compressor, the evaporator being located so as to be subjected to anenvironment having varying temperatures, the heat pump system being coupled to extract heat from the enviroment via the refrigerant passed through the evaporator and to deliver extracted heat to the condenser, wherein the improvement comprises: the heat pump system extracting heat from the environment and delivering a substantially constant quantity of extracted heat to the condenser via the refrigerant substantially independently of the environment temperature as the environmenttemperature varies in a given temperature range, the evaporator having at lease three working sizes, the heat pump system including means for sensing a system parameter relating to a condition of the refrigerant inside the heat pump system, the heatdelivered to the condenser being related to the condition of the parameter, and means for selectively coupling a working size of the evaporator in response to the sensed condition of the system parameter for operation in the heat pump system so as tomaintain the system parameter substantially at a
Claims
43 totalA heat pump system comprising a refrigerant, expansion valve means, an evaporator, a condenser and a compressor, the evaporator being located so as to be subjected to anenvironment having varying temperatures, the heat pump system being coupled to extract heat from the enviroment via the refrigerant passed through the evaporator and to deliver extracted heat to the condenser, wherein the improvement comprises: the heat pump system extracting heat from the environment and delivering a substantially constant quantity of extracted heat to the condenser via the refrigerant substantially independently of the environment temperature as the environmenttemperature varies in a given temperature range, the evaporator having at lease three working sizes, the heat pump system including means for sensing a system parameter relating to a condition of the refrigerant inside the heat pump system, the heatdelivered to the condenser being related to the condition of the parameter, and means for selectively coupling a working size of the evaporator in response to the sensed condition of the system parameter for operation in the heat pump system so as tomaintain the system parameter substantially at a