Multi-temperature evaporator refrigeration system with variable speed compressor

A refrigeration appliance, comprising:

• a single evaporator located in said refrigeration appliance;
• a single compressor;
• a condenser;
• a refrigerant circuit comprising a series of conduits for providing a flow of refrigerant through said condenser, said evaporator and said compressor;
• a plurality of restriction devices in said series of conduits connecting said condenser with said evaporator, said restriction devices operating at a plurality of different pressure levels;
• valve means in said refrigerant circuit for directing refrigerant to a selected one of said restriction devices;
• a selectively variable temperature compartment in communication with said evaporator;
• a controlled temperature compartment having a phase change material associated with and positioned for heat transfer with said controlled temperature compartment, said phase change material further being in communication with said evaporator such that said phase change material is maintained at said transition temperature;
• and
• means for controlling said valve means for selectively maintaining said variable temperature compartment at any of a plurality of selectable temperature and selectable humidity levels such that said variable temperature compartment is supplied with chilled air at the required temperature and humidity.

A refrigeration appliance, comprising:

• a plurality of refrigeration compartments;
• a plenum in communication with each of said compartments;
• a single evaporator located in said plenum;
• a condenser;
• a compressor fluidly interconnected with said evaporator and said condenser for pumping refrigerant through said evaporator and said condenser;
• means for operating said single evaporator at a plurality of different pressure levels;
• means for selectively opening and closing communication between said plenum and each of said compartments;
• and
• means for selectively maintaining each of said compartments at any of a plurality of selectable temperature and selectable humidity levels such that each of said compartments is supplied with chilled air at the required temperature and humidity.

A refrigeration appliance, comprising:

• a refrigeration compartment;
• a plenum in communication with said compartment;
• a single evaporator located in said plenum;
• a condenser;
• a single compressor fluidly interconnected with said evaporator and said condenser for pumping refrigerant through said evaporator and said condenser;
• means for selecting a temperature level for said compartment;
• means for selecting a humidity level for said compartment;
• means for operating said evaporator at a plurality of different pressure levels in response to said temperature level selecting means and said humidity level selecting means such that said compartment is supplied with chilled air at the required temperature and humidity;
• a subordinate compartment, said subordinate compartment positioned adjacent said compartment;
• and
• a supply duct for providing communication between said Subordinate compartment and said compartment wherein said subordinate compartment is cooled by controlled air flow between said subordinate compartment and said compartment.

A refrigerator appliance comprising:

• a refrigeration compartment;
• a plenum in communication with said compartment;
• a single evaporator located in said plenum;
• a condenser;
• a single compressor fluidly interconnected with said evaporator and said condenser for pumping refrigerant through said evaporator and said condenser;
• means for selecting a temperature level for said compartment;
• means for selecting a humidity level for said compartment;
• means for operating said evaporator at a plurality of different pressure levels in response to said temperature level selecting means and said humidity level selecting means such that said compartment is supplied with chilled air at the required temperature and humidity;
• a first restriction device fluidly interconnected between said condenser and said evaporator, said restriction device operating at a first pressure level;
• a second restriction device fluidly interconnected between said condenser and said evaporator, said second restriction device operating at a pressure level higher than said first pressure level;
• and
• a third restriction device fluidly interconnected between said condenser and said evaporator, said third restriction device operating at a pressure level higher than said second pressure level.

A refrigerator appliance comprising:

• a refrigeration compartment;
• a plenum in communication with said compartment;
• a single evaporator located in said plenum;
• a condenser;
• a single compressor fluidly interconnected with said evaporator and said condenser for pumping refrigerant through said evaporator and said condenser;
• means for selecting a temperature level for said compartment;
• means for selecting a humidity level for said compartment;
• means for operating said evaporator at a plurality of different pressure levels in response to said temperature level selecting means and said humidity level selecting means such that said compartment is supplied with chilled air at the required temperature and humidity;
• a controlled temperature compartment having a phase change material associated with and positioned for heat transfer with said controlled temperature compartment;
• a heat transfer chamber disposed adjacent of said phase change material, said plenum in communication with said heat transfer chamber;
• and
• means for selectively opening and closing communication between said plenum and said heat transfer chamber such that said phase change material is maintained at its liquid/solid transition temperature.

A method of operating a refrigeration appliance having a refrigerator compartment, a plenum in communication with said compartment, a single evaporator located in said plenum, a condenser and a single compressor fluidly interconnected with said evaporator and said condenser, a controlled temperature compartment having a phase change material associated with and positioned for heat transfer with said controlled temperature compartment, and a heat transfer chamber disposed adjacent of said phase change material, said plenum in communication with said heat transfer chamber, comprising the steps of:

• selecting a temperature level for said compartment;
• selecting a humidity level for said compartment;
• and
• operating said evaporator at a plurality of different pressure levels in response to said temperature level selecting means and said humidity level selecting means such that said compartment is supplied with chilled air at the required temperature and humidity;
• selectively opening and closing communication between said plenum and said heat transfer chamber such that said phase change material is maintained at its liquid/solid transition temperature.