Cold storage heat exchanger

Abstract

A cold storage heat exchanger for exchanging heat with air flowing therearound includes a refrigerant passage in which refrigerant flows, and a cold storage container that accommodates therein cold storage materials which exchanges heat with the refrigerant flowing through the refrigerant passage and retains the amount of heat from the refrigerant. The cold storage materials having different melting points are accommodated in the cold storage container.

What is claimed is: 
     
         1 . A cold storage heat exchanger for exchanging heat with air flowing therearound, the cold storage heat exchanger comprising:
 a refrigerant passages in which refrigerant flows; and   a cold storage container that accommodates therein a plurality of cold storage materials which exchange heat with the refrigerant flowing through the refrigerant passage and which retain an amount of heat from the refrigerant, wherein the plurality of cold storage materials having different melting points are accommodated in the cold storage container.   
     
     
         2 . The cold storage heat exchanger according to  claim 1 , wherein:
 the plurality of cold storage materials include a cold storage material having a high melting point, and a cold storage material having a low melting point; and   the cold storage material having the high melting point is provided on an upstream side of the cold storage material having the low melting point in a flow direction of air.   
     
     
         3 . The cold storage heat exchanger according to  claim 1 , wherein:
 the cold storage container is one of a plurality of cold storage containers;   one type of cold storage material of the plurality of cold storage materials is accommodated in each of the plurality of cold storage containers; and   a cold storage material of the plurality of cold storage materials that is accommodated in at least a part of the plurality of cold storage containers has a different melting point from that of a cold storage material of the plurality of cold storage materials that is accommodated in another one of the plurality of cold storage containers.   
     
     
         4 . The cold storage heat exchanger according to  claim 1 , wherein:
 the plurality of cold storage materials are two cold storage materials having different melting points;   a melting point of a cold storage material of the two cold storage materials that has a high melting point ranges from 5° C. to 25° C.;   a melting point of a cold storage material of the two cold storage materials that has a low melting point ranges from 0° C. to 15° C.; and   when the melting point of the cold storage material having the high melting point ranges from 5° C. to 15° C., the melting point of the cold storage material having the low melting point is 0° C. or higher, and is lower than the melting point of the cold storage material having the high melting point.   
     
     
         5 . The cold storage heat exchanger according to  claim 1 , further comprising a refrigerant pipe that is disposed on a least one surface of the cold storage container, wherein the refrigerant pipe includes the refrigerant passages. 
     
     
         6 . The cold storage heat exchanger according to  claim 2 , wherein:
 the cold storage container includes a plurality of cases independent of each other;   the plurality of cases are arranged to be different between on an upstream side and on a downstream side in the flow direction of air; and   each of the plurality of cold storage materials having different melting points is accommodated in a corresponding one of the plurality of cases.   
     
     
         7 . The cold storage heat exchanger according to  claim 6 , wherein each of the plurality of cases includes at least one sealing port through which its corresponding one of the plurality of cold storage materials is sealed. 
     
     
         8 . The cold storage heat exchanger according to  claim 1 , further comprising a partition that divides inside of the cold storage container, wherein each of the plurality of cold storage materials having different melting points is accommodated in a corresponding one of a plurality of spaces divided by the partition. 
     
     
         9 . The cold storage heat exchanger according to  claim 8 , wherein the cold storage container includes at least one sealing port through which the plurality of cold storage materials are sealed. 
     
     
         10 . The cold storage heat exchanger according to  claim 7 , wherein the at least one sealing port is provided at an outer periphery of the cold storage container or its corresponding one of the plurality of cases on an upstream side or on a downstream side in the flow direction of air. 
     
     
         11 . The cold storage heat exchanger according to  claim 1 , wherein the plurality of cold storage materials include paraffin or hydrate as their main component. 
     
     
         12 . The cold storage heat exchanger according to  claim 4 , wherein:
 a carbon number of paraffin used for the cold storage material having the high melting point is 16 or 15;   a carbon number of paraffin used for the cold storage material having the low melting point is 15 or 14;   when the carbon number of paraffin for the cold storage material having the high melting point is 16, the carbon number of paraffin for the cold storage material having the low melting point is 15 or 14; and   when the carbon number of paraffin for the cold storage material having the high melting point is 15, the carbon number of paraffin for the cold storage material having the low melting point is 14.   
     
     
         13 . The cold storage heat exchanger according to  claim 9 , wherein the at least one sealing port is provided at an outer periphery of the cold storage container or its corresponding one of the plurality of cases on an upstream side or on a downstream side in the flow direction of air.