Heat exchanger

Abstract

A heat exchanger to be used as a heater core includes a pair of header tanks spaced apart from each other, a plurality of flat heat exchange tubes which are disposed between the two header tanks at predetermined intervals along a longitudinal direction of the header tanks with their width direction coinciding with an air flow direction and whose opposite end portions are connected to the header tanks, and a plurality of corrugate fins each disposed between the adjacent heat exchange tubes. Each heat exchange tube has an inner height Ht of 0.7 mm to 1.2 mm and a width of 24 mm to 30 mm as measured in the air flow direction. Each corrugate fin has a fin height Hf of 5.5 mm to 8.5 mm. This heat exchanger exhibits excellent heat radiation performance and low resistance to air flow and water flow.

1 . A heat exchanger comprising: 
 a pair of header tanks spaced apart from each other;    a plurality of flat heat exchange tubes which are disposed between the two header tanks at predetermined intervals along a longitudinal direction of the header tanks with their width direction coinciding with an air flow direction and whose opposite end portions are connected to the corresponding header tanks; and    a plurality of corrugate fins each comprising wave crest portions, wave trough portions, and flat connection portions connecting together the corresponding wave crest portions and wave trough portions, and each disposed between the adjacent heat exchange tubes;    wherein each heat exchange tube has an inner height of 0.7 mm to 1.2 mm and a width of 24 mm to 30 mm as measured in the air flow direction, and each corrugate fin has a fin height of 5.5 mm to 8.5 mm, the fin height being the direct distance between the wave crest portion and the wave trough portion.    
   
   
       2 . A heat exchanger according to  claim 1 , wherein the inner height of each heat exchange tube is 0.8 mm to 1.0 mm.  
   
   
       3 . A heat exchanger according to  claim 1 , wherein the fin height of each corrugate fin is 6.2 mm to 7.5 mm.  
   
   
       4 . A heat exchanger according to  claim 1 , wherein each heat exchange tube comprises a pair of flat walls facing each other, two side walls extending between opposite side ends of the two flat walls, and a reinforcement wall extending between widthwise intermediate portions of the two flat walls; 
 one of the two flat walls comprises a first flat-wall-forming portion;    the other flat wall comprises two second flat-wall-forming portions which are formed integrally with the corresponding opposite side ends of the first flat-wall-forming portion via the side walls and whose side ends located opposite the corresponding side walls butt against each other;    the reinforcement wall comprises two reinforcement-wall-forming portions which are formed integrally with the corresponding butting side ends of the two second flat-wall-forming portions and in such a manner as to project toward the first flat-wall-forming portion and whose projecting end portions abut the first flat-wall-forming portion; and    two bend portions are formed integrally with corresponding projecting ends of the two reinforcement-wall-forming portions and in such a manner as to extend toward the corresponding side walls, and are joined to the first flat-wall-forming portion.    
   
   
       5 . A heat exchanger according to  claim 4 , wherein the inner height of each heat exchange tube is the direct distance between an inner surface of the first flat-wall-forming portion and an inner surface of the second flat-wall-forming portion.