Patent ID: 8408017
Filing Date: 2013-04-02
Classification: F25B,F25C,F25D

Abstract:
1. A refrigeration system, comprising: an evaporator heat exchange coupled to a load to be chilled to within a selected temperature range; an adjustable expansion valve for metering refrigerant to said evaporator; a variable speed compressor for delivering refrigerant to said expansion valve; means for sensing a chilling requirement placed on said refrigeration system by the load that is to be provided by said refrigeration system in order for said refrigeration system to cool the load to within the selected temperature range; means responsive to said sensing means for selecting the duration of a time interval during and throughout which said refrigeration system is to provide the sensed chilling requirement to the load; means responsive to each of said sensing and selecting means for operating said refrigeration system to control the speed of said compressor to deliver refrigerant to said expansion valve, and to adjust said expansion valve to meter refrigerant to said evaporator, at flow rates such that said refrigeration system provides the sensed chilling requirement to the load during and throughout the selected time interval, whereby said refrigeration system provides a cooling output over a selected time interval that closely matches the chilling requirement of the load; wherein the load is a frozen product dispenser and said evaporator is heat exchange coupled to a freeze barrel of the frozen product dispenser to chill product in the freeze barrel to within the selected temperature range, the freeze barrel being of a type from which frozen product is dispensed and into which relatively warm product is flowed to replace dispensed product, whereby the freeze barrel places on said refrigeration system a chilling requirement that varies in accordance with the quantity and temperature of the flows of relatively warm replacement product into the freeze barrel, so that said operating means operates said refrigeration system to control the speed of operation of said compressor to deliver refrigerant to said expansion valve, and to adjust said expansion valve to meter refrigerant to said evaporator, at flow rates such that said refrigeration system provides the sensed chilling requirement to the freeze barrel during and throughout the selected time interval; and wherein said sensing means comprises means for monitoring the quantity and temperature of relatively warm replacement product flowed into the freeze barrel, and means responsive to said monitoring means for determining the number of Btu's of cooling required to be provided by said refrigeration system to the freeze barrel to chill product in the freeze barrel to within the selected temperature range, said operating means being responsive to said sensing means and said selecting means to operate said refrigeration system to have a cooling capacity closely matching the immediate and dynamically changing chilling requirements of the freeze barrel.