Patent ID: 7665225
Filing Date: 2010-02-23
Classification: D06F

Abstract:
1. A drying apparatus comprising: a housing; a drying chamber mounted in the housing for containing articles to be dried, said drying chamber including an air inlet where drying air is delivered to said drying chamber and an air outlet where drying air leaves said drying chamber; an air flow path connecting said air inlet to said air outlet to form a substantially closed drying loop; a blower arranged to circulate air in said drying loop and through said drying chamber; a heat pump comprising: a refrigerant loop; a compressor arranged to circulate refrigerant in said refrigerant loop under pressure, said compressor having a power consumption; a first heat exchanger connected to said refrigerant loop and arranged in said drying loop so that heat from drying air leaving said drying chamber is transferred to said refrigerant, reducing the temperature of said drying air to below dew point so that moisture extracted from articles in said drying chamber condenses out of said drying air; a valve in said refrigerant loop, said valve controlling the flow of refrigerant into said first heat exchanger; a second heat exchanger connected to said refrigerant loop and arranged in said drying loop between said first heat exchanger and said drying chamber so that heat from said refrigerant is transferred to said drying air entering said drying chamber; and a refrigerant subcooler in said refrigerant loop and connected between a discharge of said second heat exchanger and said valve, said refrigerant subcooler comprising a third heat exchanger configured to extract a quantity of heat from refrigerant leaving said second heat exchanger, the quantity of heat extracted being modulated to be substantially equal to the power consumption of said compressor, said quantity of heat being removed from said refrigerant after said refrigerant has warmed said drying air, wherein said quantity of heat is removed from said drying apparatus, wherein said third heat exchanger is a refrigerant to liquid heat exchanger constructed to transfer heat from said refrigerant to a liquid coolant and said drying apparatus includes a coolant flow oath for delivering liquid coolant to said third heat exchanger from a source outside said drying apparatus and returning said liquid coolant to a location outside said drying apparatus.