초록 ▼

A refrigeration module removably suitable for use in either a refrigerator or a freezer uses signals from a series of temperature sensors for refrigeration control. An automatic defrost cycle is initiated when the evaporator outlet temperature drops to a value equal to the inlet temperature and is a

A refrigeration module removably suitable for use in either a refrigerator or a freezer uses signals from a series of temperature sensors for refrigeration control. An automatic defrost cycle is initiated when the evaporator outlet temperature drops to a value equal to the inlet temperature and is accompanied by a constant or rising temperature in the refrigerated cabin to which the module is connected. Field service is limited to an exchange of modules, so that refrigerating gas is not lost into the environment.

대표청구항 ▼

[ What is claimed is:] [1.] A self-contained refrigeration module comprising:(a) A cabinet provided with a cold air outlet port, a cold air return port, an ambient air supply port and an ambient air discharge port;(b) Insulative wall means defining a cold compartment within said cabinet, said cold c

[ What is claimed is:] [1.] A self-contained refrigeration module comprising:(a) A cabinet provided with a cold air outlet port, a cold air return port, an ambient air supply port and an ambient air discharge port;(b) Insulative wall means defining a cold compartment within said cabinet, said cold compartment being in communication with said cold air outlet port and with said cold air return port and being isolated from said ambient air supply port and from said ambient air discharge port;(c) Fan means mounted inside said cabinet for causing a flow of ambient air along a first path from said ambient air supply port to said ambient air discharge port and a flow of cold air along a second path from said cold air return port to said cold air outlet port;(d) A compressor mounted inside said cabinet and outside said cold compartment for compressing a refrigerating gas;(e) A condenser mounted inside said cabinet across said first path for receiving compressed refrigerating gas from said compressor and condensing said compressed refrigerating gas into a refrigerating liquid;(f) An evaporator mounted inside said cold compartment across said second path, for receiving refrigerating liquid from said condenser and vaporizing said refrigerating liquid to produce a cold refrigerating gas, said evaporator being provided with heat transfer surfaces for transferring heat from said cold air to said cold refrigerating gas thereby generating a spent refrigerating gas for return to said compressor;(g) A first temperature sensor for generating a first temperature signal corresponding to the temperature of said cold refrigerating gas;(h) A second temperature sensor for generating a second temperature signal corresponding to the temperature of said spent refrigerating gas;(i) A third temperature sensor for generating a third temperature signal corresponding to the temperature of said second flow of air at said cold air return port;(j) A heater valve for defrosting said evaporator by selectively directing compressed refrigerating gas thereto; and(k) Computing means for controlling said heater valve to direct said compressed refrigerating gas to said evaporator when said first and second temperature signals differ from each other by less than a predetermined minimum amount, and said third temperature signal increases more than a predetermined maximum amount in a predetermined time.