Cooling apparatus

Abstract

A cooling apparatus that cools a cooling target object while causing the cooling target object generate internal heat by an electromagnetic wave and that is capable of efficiently producing a subcooling state of the cooling target object is provided. The cooling apparatus includes a refrigeration machine which cools the cooling target object, an electromagnetic wave irradiation device which irradiates the cooling target object with an electromagnetic wave so as to cause the internal heat generation in the cooling target object and has a variable frequency of the irradiating electromagnetic wave, and a controller which controls operations of the refrigeration machine and the electromagnetic wave irradiation device and which performs a subcooling operation of cooling the cooling target object using the refrigeration machine while irradiating the cooling target object with an electromagnetic wave. The controller performs a preliminary operation of controlling the electromagnetic wave irradiation device such that the electromagnetic wave irradiation device irradiates the cooling target object with the electromagnetic waves of various frequencies by changing the frequency of the electromagnetic wave to be irradiated to determine a subcooling operation frequency which is a frequency of the electromagnetic wave to be irradiated to the cooling target object by the electromagnetic wave irradiation device in the subcooling operation. The controller controls the electromagnetic wave irradiation device so that the electromagnetic wave irradiation device irradiates the electromagnetic wave of the subcooling operation frequency determined in the preliminary operation in the subcooling operation.

1 . A cooling apparatus ( 100 ) comprising:
 a refrigeration machine ( 200 ) configured to cool a cooling target object (M);   an electromagnetic wave irradiation device ( 300 ) configured to irradiate the cooling target object with an electromagnetic wave so as to cause internal heat generation in the cooling target object, a frequency of the electromagnetic wave to be irradiated being variable; and   a controller ( 400 ) configured to control operations of the refrigeration machine and the electromagnetic wave irradiation device and perform a cooling operation of cooling the cooling target object by using the refrigeration machine while irradiating the electromagnetic wave to the cooling target object, wherein   the controller
 is configured to perform a preliminary operation of controlling the electromagnetic wave irradiation device such that the electromagnetic wave irradiation device irradiates the cooling target object with the electromagnetic wave of various frequencies by changing the frequency of the electromagnetic wave to be irradiated to determine a cooling operation frequency (f 1 ) which is a frequency of the electromagnetic wave to be irradiated to the cooling target object by the electromagnetic wave irradiation device in the cooling operation, and 
 is configured to control the electromagnetic wave irradiation device so that the electromagnetic wave irradiation device irradiates the electromagnetic wave of the cooling operation frequency determined in the preliminary operation in the cooling operation. 
   
     
     
         2 . The cooling apparatus according to  claim 1 , further comprising:
 a temperature sensor ( 500 ) configured to measure a temperature of the cooling target object, wherein   the controller is configured to determine, in the preliminary operation, the cooling operation frequency in accordance with the temperature measured by the temperature sensor at a time of irradiation with the electromagnetic waves of each of the various frequencies.   
     
     
         3 . The cooling apparatus according to  claim 2 , wherein
 the controller is configured to determine, in the preliminary operation, the cooling operation frequency in accordance with a change rate of the temperature measured by the temperature sensor at the time of irradiation with the electromagnetic waves of each of the various frequencies.   
     
     
         4 . The cooling apparatus according to  claim 2 , wherein
 the controller is configured to perform the preliminary operation when the temperature detected by the temperature sensor is higher than an upper limit value of a maximum ice crystal production zone and a freezing point of the cooling target object.   
     
     
         5 . The cooling apparatus according to  claim 4 , wherein
 the controller is configured to perform the cooling operation after the preliminary operation so as to cool the cooling target object to a temperature lower than the upper limit value of the maximum ice crystal production zone.   
     
     
         6 . The cooling apparatus according to  claim 2 , wherein
 an output of the electromagnetic wave irradiated by the electromagnetic wave irradiation device is variable, and   the controller is configured to control, in the cooling operation, an output of the electromagnetic wave to be irradiated from the electromagnetic wave irradiation device in accordance with the temperature detected by the temperature sensor.   
     
     
         7 . The cooling apparatus according to  claim 2 , wherein
 in the cooling operation, the controller is configured to stop irradiation with the electromagnetic wave to the cooling target object performed by the electromagnetic wave irradiation device while continuing cooling with the refrigeration machine after the cooling target object is cooled such that the temperature detected by the temperature sensor is lowered to a predetermined temperature (T 2 ) which is lower than a lower limit value of the maximum ice crystal production zone.   
     
     
         8 . The cooling apparatus according to  claim 1 , wherein
 a frequency of the electromagnetic wave to be irradiated to the cooling target object in the cooling operation is determined in one of frequency bands of a medium wave, a short wave, a ultrashort wave, a microwave, and a centimetric wave.