Refrigerator appliance cooling system

Abstract

A sealed cooling system for a refrigerator appliance includes a sealed loop with a working fluid sealed within the sealed loop, a compressor, an evaporator, an expansion device, and a modulator. The modulator has a reservoir and a supply conduit. The reservoir of the modulator is positioned around an outlet conduit of the evaporator. A first end portion of the supply conduit is coupled to an inlet conduit of the evaporator. A second end portion of the supply conduit is coupled to the reservoir of the modulator. The working fluid is flowable into and out of the reservoir of the modulator through the supply conduit of the modulator.

What is claimed is: 
     
         1 . A refrigerator appliance comprising:
 a cabinet;   a fresh food chamber defined in the cabinet;   a freezer chamber defined in the cabinet; and   a sealed cooling system configured to provide cooled air to the fresh food chamber and the freezer chamber, the sealed cooling system comprising:
 a sealed loop with a working fluid sealed within the sealed loop; 
 a compressor; 
 a condenser downstream of the compressor with respect to the flow direction of the working fluid; 
 an evaporator downstream of the condenser with respect to the flow direction of the working fluid; 
 an expansion device between the condenser and the evaporator; and 
 a modulator having a reservoir and a supply conduit, the reservoir of the modulator positioned around an outlet conduit of the evaporator, a first end portion of the supply conduit coupled to an inlet conduit of the evaporator, a second end portion of the supply conduit coupled to the reservoir of the modulator, the working fluid flowable into and out of the reservoir of the modulator through the supply conduit of the modulator. 
   
     
     
         2 . The refrigerator appliance of  claim 1 , wherein the evaporator is a single evaporator and is the only evaporator in the refrigerator appliance, the single evaporator in fluid communication with the fresh food chamber to provide a flow of chilled air from the single evaporator to the fresh food chamber and the single evaporator in fluid communication with the freezer chamber to provide a flow of chilled air from the evaporator to the freezer chamber. 
     
     
         3 . The refrigerator appliance of  claim 1 , wherein the outlet conduit of the evaporator extends through the reservoir of the modulator. 
     
     
         4 . The refrigerator appliance of  claim 3 , wherein the outlet conduit of the evaporator is positioned concentrically with an interior volume of the reservoir. 
     
     
         5 . The refrigerator appliance of  claim 1 , wherein the modulator forms a dead end branch for the working fluid. 
     
     
         6 . The refrigerator appliance of  claim 1 , further comprising a movable damper assembly configured to move between a first position wherein the evaporator is in fluid communication with the fresh food chamber to provide a flow of chilled air from the evaporator to the fresh food chamber and a second position wherein the evaporator is in fluid communication with the freezer chamber to provide a flow of chilled air from the evaporator to the freezer chamber. 
     
     
         7 . The refrigerator appliance of  claim 1 , further comprising a bridge chamber defined in the cabinet, the bridge chamber positioned between the fresh food chamber and the freezer chamber, wherein the evaporator is positioned in the bridge chamber. 
     
     
         8 . The refrigerator appliance of  claim 7 , wherein the bridge chamber comprises a first inlet in fluid communication with the fresh food chamber, a first outlet in fluid communication with the fresh food chamber, a second inlet in fluid communication with the freezer chamber, and a second outlet in fluid communication with the freezer chamber. 
     
     
         9 . The refrigerator appliance of  claim 7 , further comprising a fan positioned in the bridge chamber and a plenum defined within the bridge chamber between the evaporator and the fan. 
     
     
         10 . A sealed cooling system for a refrigerator appliance, the refrigerator appliance comprising a freezer chamber and a fresh food chamber, the sealed cooling system comprising:
 a sealed loop with a working fluid sealed within the sealed loop;   a compressor;   a condenser downstream of the compressor with respect to the flow direction of the working fluid;   an evaporator downstream of the condenser with respect to the flow direction of the working fluid;   an expansion device between the condenser and the evaporator; and   a modulator having a reservoir and a supply conduit, the reservoir of the modulator positioned around an outlet conduit of the evaporator, a first end portion of the supply conduit coupled to an inlet conduit of the evaporator, a second end portion of the supply conduit coupled to the reservoir of the modulator, the working fluid flowable into and out of the reservoir of the modulator through the supply conduit of the modulator.   
     
     
         11 . The sealed cooling system of  claim 10 , wherein the evaporator is a single evaporator, the single evaporator in fluid communication with the fresh food chamber to provide a flow of chilled air from the single evaporator to the fresh food chamber and the single evaporator in fluid communication with the freezer chamber to provide a flow of chilled air from the evaporator to the freezer chamber. 
     
     
         12 . The sealed cooling system of  claim 10 , wherein the outlet conduit of the evaporator extends through the reservoir of the modulator. 
     
     
         13 . The sealed cooling system of  claim 12 , wherein the outlet conduit of the evaporator is positioned concentrically with an interior volume of the reservoir. 
     
     
         14 . The sealed cooling system of  claim 10 , wherein the modulator forms a dead end branch for the working fluid. 
     
     
         15 . The sealed cooling system of  claim 10 , further comprising a movable damper assembly configured to move between a first position wherein the evaporator is in fluid communication with the fresh food chamber to provide a flow of chilled air from the evaporator to the fresh food chamber and a second position wherein the evaporator is in fluid communication with the freezer chamber to provide a flow of chilled air from the evaporator to the freezer chamber. 
     
     
         16 . The sealed cooling system of  claim 10 , wherein the evaporator is positioned in a bridge chamber defined in the cabinet of the refrigerator appliance, the bridge chamber positioned between the fresh food chamber and the freezer chamber. 
     
     
         17 . The sealed cooling system of  claim 16 , wherein the bridge chamber comprises a first inlet in fluid communication with the fresh food chamber, a first outlet in fluid communication with the fresh food chamber, a second inlet in fluid communication with the freezer chamber, and a second outlet in fluid communication with the freezer chamber. 
     
     
         18 . The sealed cooling system of  claim 16 , further comprising a fan positioned in the bridge chamber and a plenum defined within the bridge chamber between the evaporator and the fan.