Cooling Box

Abstract

The controller of a cooling box is configured such that when the temperature of the warm head of a Stirling refrigerating machine exceeds a reference temperature, it maximizes the speed of a heat radiation fan and the output of a circulation pump, and minimizes the output of the Stirling refrigerating machine. If the temperature of the warm head exceeds a critical temperature even after this control, it stops the Stirling refrigerating machine. Therefore, as compared with the case of stopping the Stirling refrigerating machine immediately after the temperature of the warm head has exceeded the critical temperature, the reliability of the cooling box can be improved.

1 . A cooling box incorporating a Stirling refrigerating machine, comprising: 
 temperature detection means for detecting a temperature of a warm head of said Stirling refrigerating machine; and    control means for controlling such that an increase of the temperature of said warm head is restricted before stopping of said Stirling refrigerating machine, in response to the event that a detected temperature of said temperature detection means has exceeded a predetermined reference temperature.    
   
   
       2 . The cooling box according to  claim 1 , further comprising: 
 a heat radiator receiving hot heat from the warm head of said Stirling refrigerating machine via a refrigerant and performing heat radiation to an environment outside the box; and    a heat radiation fan promoting the heat radiation of said heat radiator, wherein    said control means is adapted to    maximize the quantity of air supplied by said heat radiation fan in response to the event that the detected temperature of said temperature detection means has exceeded said reference temperature, and    thereafter, reduce an output of said Stirling refrigerating machine when the detected temperature of said temperature detection means does not become lower than said reference temperature even after a lapse of a predetermined time.    
   
   
       3 . The cooling box according to  claim 1 , further comprising a refrigerant circulation circuit transmitting hot heat of said warm head via a refrigerant to an outer wall surface of the box to prevent condensation, wherein 
 said control means is adapted to    maximize the quantity of the refrigerant circulated in said refrigerant circulation circuit in response to the event that the detected temperature of said temperature detection means has exceeded said reference temperature, and    thereafter, reduce an output of said Stirling refrigerating machine when the detected temperature of said temperature detection means does not become lower than said reference temperature even after a lapse of a predetermined time.    
   
   
       4 . The cooling box according to  claim 1 , further comprising: 
 a heat radiator receiving hot heat from the warm head of said Stirling refrigerating machine via a refrigerant and performing heat radiation to an environment outside the box;    a heat radiation fan promoting the heat radiation of said heat radiator; and    a refrigerant circulation circuit transmitting the hot heat of said warm head via the refrigerant to an outer wall surface of the box to prevent condensation, wherein    said control means is adapted to    maximize the quantity of air supplied by said heat radiation fan in response to the event that the detected temperature of said temperature detection means has exceeded said reference temperature, and    thereafter, maximize the quantity of the refrigerant circulated in said refrigerant circulation circuit when the detected temperature of said temperature detection means does not become lower than said reference temperature even after a lapse of a first predetermined time, and    further, reduce an output of said Stirling refrigerating machine when the detected temperature of said temperature detection means does not become lower than said reference temperature even after a lapse of a second predetermined time.    
   
   
       5 . The cooling box according to  claim 1 , further comprising: 
 a heat radiator receiving hot heat from the warm head of said Stirling refrigerating machine via a refrigerant and performing heat radiation to an environment outside the box;    a heat radiation fan promoting the heat radiation of said heat radiator; and    a refrigerant circulation circuit transmitting the hot heat of said warm head via the refrigerant to an outer wall surface of the box to prevent condensation, wherein    said control means is adapted to    maximize the quantity of the refrigerant circulated in said refrigerant circulation circuit in response to the event that the detected temperature of said temperature detection means has exceeded said reference temperature, and    thereafter, maximize the quantity of air supplied by said heat radiation fan when the detected temperature of said temperature detection means does not become lower than said reference temperature even after a lapse of a first predetermined time, and    further, reduce an output of said Stirling refrigerating machine when the detected temperature of said temperature detection means does not become lower than said reference temperature even after a lapse of a second predetermined time.    
   
   
       6 . The cooling box according to  claim 1 , wherein said control means reduces the output of said Stirling refrigerating machine in a stepwise manner.