Heat Exchanger

Abstract

A heat exchanger that performs heat exchange between a refrigerant and outside air includes: a plurality of tubes arranged in parallel; a fin provided between the tubes adjacent to each other. The fin includes: contact portions alternately in contact with one and the other of the adjacent tubes; wall portions each connecting the contact portions adjacent to each other so as to connect the adjacent tubes; an extension portion extending from the contact portions and the wall portions and protruding upstream in a flow direction of the outside air from the tubes; and a plurality of louvers provided on each of the wall portions continuously along the flow direction of the outside air. A downstream end portion of a most upstream louver in the flow direction of the outside air is located upstream of a tip end of each of the tubes in the flow direction of the outside air.

1 . A heat exchanger configured to perform heat exchange between a refrigerant circulating in a refrigeration cycle and outside air, the heat exchanger comprising:
 a plurality of tubes arranged in parallel and configured to allow the refrigerant to flow therethrough;   a fin provided between adjacent tubes and configured to allow the outside air to pass therethrough, wherein the fin includes
 a plurality of contact portions alternately in contact with one and another of the adjacent tubes, 
 a plurality of wall portions each connecting the contact portions adjacent to each other so as to connect the adjacent tubes, 
 an extension portion extending from the contact portions and the wall portions and protruding upstream in a flow direction of the outside air from the tubes, and 
 a plurality of louvers provided in each of the wall portions continuously along the flow direction of the outside air, 
   each of the wall portions includes a flat plate portion formed in a flat plate shape, and arc portions each curved in an arc shape from the flat plate portion toward a corresponding one of the contact portions,   the louvers include a first louver formed most upstream in the flow direction of the outside air in the extension portion, and a second louver formed downstream of the first louver in the flow direction of the outside air on a downstream side of an upstream end portion in the flow direction of the outside air in the tubes,   the first louver and the second louver are formed at a same height throughout a height direction of the flat plate portion, and   a downstream end portion of the first louver is located upstream of a tip end of each of the tubes in the flow direction of the outside air, and is formed at a same cut-and-raised height over a height direction of the downstream end portion.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein the first louver is a single-louver in which only the downstream end portion is cut and raised in one side surface of athe wall portion, and
 the second louver is a double-louver in which the downstream end portion is cut and raised in the one side surface of the wall portion and an upstream end portion is cut and raised in another side surface of the wall portion.   
     
     
         3 . The heat exchanger according to  claim 1 , wherein a length of a plane portion in which the first louver is not provided in the extension portion is shorter than a length of a louver forming portion in which the first louver is provided in the extension portion. 
     
     
         4 . The heat exchanger according to  claim 1 ,
 wherein a number of the downstream end portion of the first louver located upstream of the tip end of a tube at each of the wall portions is one.   
     
     
         5 . The heat exchanger according to  claim 1 ,
 wherein a tube is disposed such that a heat exchange surface thereof in contact with the fin is horizontal.   
     
     
         6 . The heat exchanger according to  claim 1 , wherein a wall portion includes the arc portions each curved in an arc shape toward a corresponding one of the contact portions, and
 the louvers are not formed in the arc portions.