Refrigerant evaporator

Abstract

In a refrigerant evaporator, a core has tubes that are arranged in a core width direction and at least in two rows including a first row and a second row. The first row is disposed downstream of the second row with respect to a flow direction of an external fluid. The tubes of the first row provide a refrigerant upward path and a refrigerant downward path. The core has a thickness equal to or less than 50 mm with respect to the flow direction of the external fluid, and a width equal to or greater than 220 mm with respect to the core width direction. The upward path is further than the downward path with respect to a refrigerant inlet disposed at an end of a first header tank, and has a width equal to or less than 95 mm with respect to the core width direction.

1 . A refrigerant evaporator for performing heat exchange between a refrigerant and an external fluid, the refrigerant evaporator comprising:
 a core including a plurality of tubes, the tubes arranged in a core width direction and at least in two rows including a first row and a second row, the first row being located downstream of the second row with respect to a flow direction of the external fluid;   a first header tank including a first upper tank portion and a first lower tank portion, the first upper tank portion being in communication with upper ends of the tubes of the first row, the first lower tank portion being in communication with lower ends of the tubes of the first row;   a second header tank including a second upper tank portion and a second lower tank portion, the second upper tank portion being in communication with upper ends of the tubes of the second row, the second lower tank portion being in communication with lower ends of the tubes of the second row;   a refrigerant inlet disposed at an end of the first header tank;   a refrigerant outlet disposed at an end of the second header tank, the end of the second header tank and the end of the first header tank being on a same side with respect to the core width direction;   a first separation member disposed in the first header tank such that a first upward path through which the refrigerant flows in an upward direction and a first downward path through which the refrigerant flows in a downward direction are provided by the tubes of the first row, the first upward path and the first downward path being adjacent to each other with respect to the core width direction; and   a second separation member disposed in the second header tank such that a second upward path through which the refrigerant flows in the upward direction and a second downward path through which the refrigerant flows in the downward direction are provided by the tubes of the second row, the second upward path and the second downward path being adjacent to each other with respect to the core width direction, wherein   a thickness of the core with respect to the flow direction of the external fluid is equal to or less than 50 mm,   a width of the core with respect to the core width direction is equal to or greater than 220 mm,   the first upward path is located further than the first downward path with respect to the refrigerant inlet, and   a width of the first upward path with respect to the core width direction is equal to or less than 95 mm.   
   
   
       2 . The refrigerant evaporator according to  claim 1 , wherein
 the second upward path is located further than the second downward path with respect to the refrigerant outlet,   the first upper tank portion includes a first upper chamber that is in communication with the first upward path,   the first lower tank portion includes a first lower chamber that is in communication with the first upward path,   the second upper tank portion includes a second upper chamber that is in communication with the second upward path, and   the second lower tank portion includes a second lower chamber that is in communication with the second upward path,   the refrigerant evaporator further comprising:   a first communication portion configured to allow communication between the first upper chamber and the second upper chamber; and   a second communication portion configured to allow communication between the first lower chamber and the second lower chamber.   
   
   
       3 . The refrigerant evaporator according to  claim 2 , wherein
 the tubes are arranged only in the first row and the second row,   the width of the core is at least 220 mm and at most 350 mm, and   the width of the first upward path is at least 50 mm and at most 95 mm.   
   
   
       4 . The refrigerant evaporator according to  claim 3 , wherein
 the first communication portion is provided by a first communication member defining a first communication passage therein, and   the second communication portion is provided by a second communication member defining a second communication passage therein.   
   
   
       5 . The refrigerant evaporator according to  claim 3 , wherein
 the first upper tank portion and the second upper tank portion are disposed adjacent to each other with respect to the flow direction of the external fluid,   the first lower tank portion and the second lower tank portion are disposed adjacent to each other with respect to the flow direction of the external fluid,   the first communication portion defines a first communication opening between the first upper tank portion and the second upper tank portion, and   the second communication portion defines a second communication opening between the first lower tank portion and the second lower tank portion.   
   
   
       6 . The refrigerant evaporator according to  claim 5 , wherein
 each of the first communication opening and the second communication opening has an equivalent diameter that is at least 0.55 mm and at most 3 mm.   
   
   
       7 . The refrigerant evaporator according to  claim 3 , wherein
 the first communication portion provides a passage area greater than that of the second communication portion.   
   
   
       8 . The refrigerant evaporator according to  claim 3 , wherein
 the first communication portion provides a passage area smaller than that of the second communication portion.   
   
   
       9 . The refrigerant evaporator according to  claim 3 , wherein
 the second upward path has a width that is equal to or greater than the width of the first upward path with respect to the core width direction.   
   
   
       10 . The refrigerant evaporator according to  claim 3 , wherein
 the second upward path has a width that is equal to or less than the width of the first upward path with respect to the core width direction.   
   
   
       11 . The refrigerant evaporator according to  claim 3 , wherein
 the second separation member is disposed in the second header tank such that the tubes of the second row provide the second upward path, the second downward path and a third upward path through which the refrigerant flows in the upstream direction, and   the third upward path is located adjacent to the refrigerant outlet, the second upward path is located furthest from the refrigerant outlet and the second downward path is located between the second upward path and the third upward path.   
   
   
       12 . The refrigerant evaporator according to  claim 11 , wherein
 when the width of the first upward path is defined as L 1 , a width of the second upward path with respect to the core width direction is defined as L 2 , and the width of the core is defined as W, a sum of the width of the first upward path and the width of the second upward path satisfy a relationship of 0.24×W≦L 1 +L 2 ≦0.36×W.   
   
   
       13 . The refrigerant evaporator according to  claim 11 , wherein
 the core further includes outer fins between the adjacent tubes,   a dimension of each fin with respect to the core width direction is at least 3 mm and at most 7 mm, and   a dimension of each tube with respect to the core width direction is at least 1.1 mm and at most 2.3 mm.   
   
   
       14 . The refrigerant evaporator according to  claim 1  for being employed in a refrigerant cycle apparatus having a compressor whose operation is controlled based on a temperature of an outer surface of the core, wherein the thickness of the core is at least 12 mm and at most 50 mm. 
   
   
       15 . The refrigerant evaporator according to  claim 1  for being employed in a refrigerant cycle apparatus having a compressor whose operation is controlled based on a temperature of an outer surface of the core, wherein the thickness of the core is at least 20 mm and at most 50 mm. 
   
   
       16 . The refrigerant evaporator according to  claim 1  for being employed in a refrigerant cycle apparatus having a compressor whose operation is controlled based on a temperature of an outer surface of the core, wherein the thickness of the core is at least 37 mm and at most 50 mm. 
   
   
       17 . The refrigerant evaporator according to  claim 1  for being employed in a refrigerant cycle apparatus having a compressor whose operation is controlled based on a temperature of air downstream of the core, wherein the thickness of the core is at least 22 mm and at most 50 mm. 
   
   
       18 . The refrigerant evaporator according to  claim 1  for being employed in a refrigerant cycle apparatus having a compressor whose operation is controlled based on a temperature of air downstream of the core, wherein the thickness of the core is at least 31 mm and at most 50 mm. 
   
   
       19 . The refrigerant evaporator according to  claim 1 , wherein a total passage area of the first upward path is smaller than a passage area of the first lower tank portion. 
   
   
       20 . The refrigerant evaporator according to  claim 1 , wherein a total passage area of the first upward path is greater than a passage area of the first lower tank portion. 
   
   
       21 . The refrigerant evaporator according to  claim 1 , wherein the core is a finless-type without having outer fins between the tubes. 
   
   
       22 . The refrigerant evaporator according to  claim 1 , wherein the core includes fins between the adjacent tubes, and each of the fins is in contact with one of the adjacent tubes.