Refrigerator with system for controlling drawer temperatures

Abstract

A refrigerator is provided with a refrigerated compartment comprising one or more zones in thermal communication with each other and with each zone independently controlled and operated at a particular temperature. Each zone temperature is controlled by a separate evaporator or heat exchanger. A method for maintaining different temperatures in one or more zones in thermal communication with one another in a refrigerator is also provided.

1 . A refrigerator comprising: 
 a first zone and a second zone wherein the first zone is disposed within the second zone;    a refrigeration system comprising a first evaporator and a second evaporator connected in series and a refrigerant, the first evaporator cooling the first zone to a first temperature, the second evaporator cooling the second zone to a second temperature, and the refrigerant proceeding through the first condenser and through the second condenser;    wherein the first evaporator has a first evaporator volume and the second evaporator has a second evaporator volume;    wherein the first evaporator volume is different than the second evaporator volume; and    wherein the first temperature is different than the second temperature.    
   
   
       2 . The refrigerator of  claim 1 , wherein the refrigeration system further comprises a compressor, a condenser, a first expansion valve, a first fan for providing air flow over the first evaporator, and a second fan for providing air flow over the second evaporator.  
   
   
       3 . The refrigerator of  claim 2 , wherein the refrigerant flows continuously through the first expansion valve, through the first evaporator, through the second evaporator, through the compressor, through the condenser, and returns to the first expansion valve.  
   
   
       4 . The refrigerator of  claim 1 , wherein the refrigeration system further comprises a thermostatic controller.  
   
   
       5 . The refrigerator of  claim 1 , wherein the first temperature and the second temperature are above-freezing.  
   
   
       6 . The refrigerator of  claim 1 , wherein the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature.  
   
   
       7 . The refrigerator of  claim 1 , wherein the refrigeration system is capable of maintaining the first temperature from 4° F. to 7° F. lower than the second temperature.  
   
   
       8 . The refrigerator of  claim 1 , wherein the first zone comprises at least one drawer.  
   
   
       9 . The refrigerator of  claim 1 , wherein: 
 the second evaporator is in air flow communication with the second zone by a second zone air inlet through which air enters the second zone, and a second zone air outlet through which air exits the second zone; and    the second zone air inlet is situated above the second zone air outlet.    
   
   
       10 . The refrigerator of  claim 1 , wherein: 
 the first evaporator is in air flow communication with the first zone by a first zone air inlet through which air enters the first zone, and a first zone air outlet through which air exits the first zone; and    the first zone air inlet is situated below the first zone air outlet.    
   
   
       11 . The refrigerator of  claim 1 , wherein: 
 the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature;    the first evaporator is in air flow communication with the first zone by a receiving duct through which air exits the first zone, a distributing duct through which air enters the first zone, and a first evaporator fan in air flow communication with the receiving duct and the distributing duct; and    the first evaporator can be housed in either the receiving duct or the distributing duct.    
   
   
       12 . The refrigerator of  claim 1 , wherein the first evaporator volume is smaller than the second evaporator volume.  
   
   
       13 . The refrigerator of  claim 1 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils have a second internal diameter and the first evaporator coils have a first internal diameter; and    wherein the second internal diameter is larger than the first internal diameter.    
   
   
       14 . The refrigerator of  claim 13 , wherein the second evaporator coils are longer than the first evaporator coils.  
   
   
       15 . The refrigerator of  claim 1 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils are longer than the first evaporator coils.    
   
   
       16 . The refrigerator of  claim 1 , further comprising a second expansion valve located between the first evaporator and second evaporator.  
   
   
       17 . A refrigerator comprising: 
 a first zone and a second zone;    a refrigeration system comprising a first evaporator and a second evaporator connected in series and a refrigerant, the first evaporator cooling the first zone to a first temperature, the second evaporator cooling the second zone to a second temperature, and the refrigerant proceeding through the first condenser and through the second condenser;    wherein the first evaporator has a first evaporator volume and the second evaporator has a second evaporator volume;    wherein the first evaporator volume is different than the second evaporator volume;    wherein the first temperature is different than the second temperature; and    wherein the first and second zone share at least one thermally conductive common wall.    
   
   
       18 . The refrigerator of  claim 17 , wherein the refrigeration system further comprises a compressor, a condenser, a first expansion valve, a first fan for providing air flow over the first evaporator, and a second fan for providing air flow over the second evaporator.  
   
   
       19 . The refrigerator of  claim 18 , wherein the refrigerant flows continuously through the first expansion valve, through the first evaporator, through the second evaporator, through the compressor, through the condenser, and returns to the first expansion valve.  
   
   
       20 . The refrigerator of  claim 17 , wherein the refrigeration system further comprises a thermostatic controller.  
   
   
       21 . The refrigerator of  claim 17 , wherein the first temperature and the second temperature are above-freezing.  
   
   
       22 . The refrigerator of  claim 17 , wherein the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature.  
   
   
       23 . The refrigerator of  claim 17 , wherein the refrigeration system is capable of maintaining the first temperature from 4° F. to 7° F. lower than the second temperature.  
   
   
       24 . The refrigerator of  claim 17 , wherein the first zone is located below the second zone.  
   
   
       25 . The refrigerator of  claim 17 , wherein the first zone is located above the second zone.  
   
   
       26 . The refrigerator of  claim 17 , wherein the first zone comprises at least one drawer.  
   
   
       27 . The refrigerator of  claim 17 , wherein: 
 the second evaporator is in air flow communication with the second zone by a second zone air inlet through which air enters the second zone, and a second zone air outlet through which air exits the second zone; and    the second zone air inlet is situated above the second zone air outlet.    
   
   
       28 . The refrigerator of  claim 17 , wherein: 
 the first evaporator is in air flow communication with the first zone by a first zone air inlet through which air enters the first zone, and a first zone air outlet through which air exits the first zone; and    the first zone air inlet is situated below the first zone air outlet.    
   
   
       29 . The refrigerator of  claim 17 , wherein: 
 the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature;    the first evaporator is in air flow communication with the first zone by a receiving duct through which air exits the first zone, a distributing duct through which air enters the first zone, and a first evaporator fan in air flow communication with the receiving duct and the distributing duct; and    the first evaporator can be housed in either the distributing duct or the receiving duct.    
   
   
       30 . The refrigerator of  claim 17 , wherein the first evaporator volume is smaller than the second evaporator volume.  
   
   
       31 . The refrigerator of  claim 17 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils have a second internal diameter and the first evaporator coils have a first internal diameter; and    wherein the second internal diameter is larger than the first internal diameter.    
   
   
       32 . The refrigerator of  claim 31 , wherein the second evaporator coils are longer than the first evaporator coils.  
   
   
       33 . The refrigerator of  claim 17 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils are longer than the first evaporator coils.    
   
   
       34 . The refrigerator of  claim 17 , further comprising a second expansion valve located between the first evaporator and second evaporator.  
   
   
       35 . A method for maintaining a first zone and a second zone of a refrigerator at different temperatures, the method comprising: 
 cooling the first zone to a first temperature with a first evaporator;    cooling the second zone to a second temperature with a second evaporator;    wherein the first zone is disposed within the second zone;    wherein the first evaporator and second evaporator are connected in series;    wherein the first evaporator has a first evaporator volume and the second evaporator has a second evaporator volume;    wherein the second evaporator volume is different than the first evaporator volume; and    wherein the first temperature is different than the second temperature.    
   
   
       36 . The method of  claim 35 , wherein the refrigeration system further comprises a compressor, a condenser, a first expansion valve, a first fan for providing air flow over the first evaporator, and a second fan for providing air flow over the second evaporator.  
   
   
       37 . The method of  claim 36 , wherein the refrigerant flows continuously through the first expansion valve, through the first evaporator, through the second evaporator, through the compressor, through the condenser, and returns to the first expansion valve.  
   
   
       38 . The method of  claim 35 , wherein the refrigeration system further comprises a thermostatic controller.  
   
   
       39 . The method of  claim 35 , wherein the first temperature and the second temperature are above-freezing.  
   
   
       40 . The method of  claim 35 , wherein the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature.  
   
   
       41 . The method of  claim 35 , wherein the first zone comprises at least one drawer.  
   
   
       42 . The method of  claim 41 , wherein the at least one drawer comprises one or more openings; and 
 wherein the first air flow passes through the one or more openings to directly cool the at least one drawer.    
   
   
       43 . The method of  claim 42 , wherein the first zone further comprises blocking means for closing the one or more openings; and 
 wherein the first air flow does not pass through the at least one drawer when the one or more openings are blocked to indirectly cool the at least one drawer.    
   
   
       44 . The method of  claim 43 , wherein a user can manipulate the blocking means to directly cool or indirectly cool the at least one drawer.  
   
   
       45 . The method of  claim 35 , wherein: 
 the second evaporator is in air flow communication with the second zone by a second zone air inlet through which air enters the second zone, and a second zone air outlet through which air exits the second zone; and    the second zone air inlet is situated above the second zone air outlet.    
   
   
       46 . The method of  claim 35 , wherein: 
 the first evaporator is in air flow communication with the first zone by a first zone air inlet through which air enters the first zone, and a first zone air outlet through which air exits the first zone; and    the first zone air inlet is situated below the first zone air outlet.    
   
   
       47 . The method of  claim 46 , wherein the first zone comprises at least one drawer; 
 wherein the drawer comprises one or more openings corresponding to the first zone air inlet;    wherein the first zone air outlet comprises an opening located above the at least one drawer; and    wherein the first air flow is maintained substantially within the at least one drawer.    
   
   
       48 . The method of  claim 35 , wherein: 
 the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature;    the first evaporator is in air flow communication with the first zone by a receiving duct through which air exits the first zone, a distributing duct through which air enters the first zone, and a first evaporator fan in air flow communication with the receiving duct and the distributing duct; and    the first evaporator can be housed in either the receiving duct or the distributing duct.    
   
   
       49 . The method of  claim 35 , wherein the first evaporator volume is smaller than the second evaporator volume.  
   
   
       50 . The method of  claim 35 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils have a second internal diameter and the first evaporator coils have a first internal diameter; and    wherein the second internal diameter is larger than the first internal diameter.    
   
   
       51 . The method of  claim 50 , wherein the second evaporator coils are longer than the first evaporator coils.  
   
   
       52 . The method of  claim 35 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils are longer than the first evaporator coils.    
   
   
       53 . The method of  claim 35 , further comprising a second expansion valve located between the first evaporator and second evaporator.  
   
   
       54 . A method for maintaining a first zone and a second zone of a refrigerator at different temperatures, the method comprising: 
 cooling the first zone to a first temperature with a first evaporator;    cooling the second zone to a second temperature with a second evaporator;    wherein the first and second zone share at least one thermally conductive common wall;    wherein the first evaporator and second evaporator are connected in series;    wherein the first evaporator has a first evaporator volume and the second evaporator has a second evaporator volume;    wherein the second evaporator volume is different than the first evaporator volume; and    wherein the second temperature is different than the first temperature.    
   
   
       55 . The method of  claim 54 , wherein the refrigeration system further comprises a compressor, a condenser, a first expansion valve, a first fan for providing air flow over the first evaporator, and a second fan for providing air flow over the second evaporator.  
   
   
       56 . The method of  claim 55 , wherein the refrigerant flows continuously through the first expansion valve, through the first evaporator, through the second evaporator, through the compressor, through the condenser, and returns to the first expansion valve.  
   
   
       57 . The method of  claim 54 , wherein the refrigeration system further comprises a thermostatic controller.  
   
   
       58 . The method of  claim 54 , wherein the first temperature and the second temperature are above-freezing.  
   
   
       59 . The method of  claim 54 , wherein the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature.  
   
   
       60 . The method of  claim 54 , wherein the first zone comprises at least one drawer.  
   
   
       61 . The method of  claim 60 , wherein the at least one drawer comprises one or more openings; and 
 wherein the first air flow passes through the one or more openings to directly cool the at least one drawer.    
   
   
       62 . The method of  claim 61 , wherein the first zone further comprises blocking means for closing the one or more openings; and 
 wherein the first air flow does not pass through the at least one drawer when the one or more openings are blocked to indirectly cool the at least one drawer.    
   
   
       63 . The method of  claim 62 , wherein a user can manipulate the blocking means to directly cool or indirectly cool the at least one drawer.  
   
   
       64 . The method of  claim 54 , wherein: 
 the second evaporator is in air flow communication with the second zone by a second zone air inlet through which air enters the second zone, and a second zone air outlet through which air exits the second zone; and    the second zone air inlet is situated above the second zone air outlet.    
   
   
       65 . The method of  claim 54 , wherein: 
 the first evaporator is in air flow communication with the first zone by a first zone air inlet through which air enters the first zone, and a first zone air outlet through which air exits the first zone; and    the first zone air inlet is situated above the first zone air outlet.    
   
   
       66 . The method of  claim 65 , wherein the first zone comprises at least one drawer; 
 wherein the drawer comprises one or more openings corresponding to the first zone air inlet;    wherein the first zone air outlet comprises an opening located above the at least one drawer; and    wherein the first air flow is maintained substantially within the at least one drawer.    
   
   
       67 . The method of  claim 54 , wherein: 
 the refrigeration system is capable of maintaining the first temperature from 2° F. to 10° F. lower than the second temperature;    the first evaporator is in air flow communication with the first zone by a receiving duct through which air exits the first zone, a distributing duct through which air enters the first zone, and a first evaporator fan in air flow communication with the receiving duct and the distributing duct; and    the first evaporator can be housed in either the receiving duct or the distributing duct.    
   
   
       68 . The method of  claim 54 , wherein the second evaporator volume is larger than the first evaporator volume.  
   
   
       69 . The method of  claim 54 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils have a second internal diameter and the first evaporator coils have a first internal diameter; and    wherein the second internal diameter is larger than the first internal diameter.    
   
   
       70 . The method of  claim 69 , wherein the second evaporator coils are longer than the first evaporator coils.  
   
   
       71 . The method of  claim 54 , wherein the first evaporator comprises first evaporator coils and the second evaporator comprises second evaporator coils; 
 wherein the second evaporator coils are longer than the first evaporator coils.    
   
   
       72 . The method of  claim 54 , further comprising a second expansion valve located between the first evaporator and second evaporator.