Heat exchanger

Abstract

A heat exchange tube 4 is formed by using a sheet member not clad with a brazing material layer, with bonding margins 4 d at which ends of the sheet member are overlapped and brazed by using a brazing material. This structure reduces the extent to which the brazing material becomes dispersed while the heat exchange tube is brazed and the likelihood of dissolution due to erosion, which makes it possible to assure the desired product quality such as corrosion resistance even when a tube material with a smaller wall thickness is used.

1 - 6 . (canceled)  
   
   
       7 . A heat exchanger having: 
 heat exchange tubes each formed by rolling sheet material; and    a pair of tanks to which ends of said heat exchange tubes on two sides along the lengthwise direction inserted therein are bonded,    wherein said heat exchange tubes are constituted with sheet material not clad with a brazing material layer; and    wherein bonding margins at which sheet material ends are made to overlap are brazed by using a brazing material.    
   
   
       8 . A heat exchanger according to  claim 7 , 
 wherein said heat exchange tubes are constituted with sheet material not clad with a brazing material layer, which includes a sacrificial corrosion layer applied onto an outer side of a core material.    
   
   
       9 . A heat exchanger according to  claim 8 , 
 wherein said bonding margins at which said sheet material ends are made to overlap are brazed by supplying a brazing material that has been supplied to tube insertion hole formation surfaces of said tanks, further to said bonding margins through capillary action.    
   
   
       10 . A heat exchanger according to  claim 9 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to tube insertion hole formation surfaces of said tanks by attaching brazing sheets to, at least, side surfaces of said tanks where said tanks are conjoined with said tubes.    
   
   
       11 . A heat exchanger according to  claim 9 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to side surfaces of said tanks at which said tanks are conjoined with said tubes, by spraying said brazing material at least onto tube insertion hole formation surfaces.    
   
   
       12 . A heat exchanger according to  claim 8 , 
 wherein said heat exchange tubes are stacked so as to alternate with outer fins; and    wherein said outer fins and edges of contact surfaces of said tube bonding margins are not in contact with each other.    
   
   
       13 . A heat exchanger according to  claim 8 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to tube insertion hole formation surfaces of said tanks by attaching brazing sheets to, at least, side surfaces of said tanks where said tanks are conjoined with said tubes.    
   
   
       14 . A heat exchanger according to  claim 8 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to side surfaces of said tanks at which said tanks are conjoined with said tubes, by spraying said brazing material at least onto tube insertion hole formation surfaces.    
   
   
       15 . A heat exchanger according to  claim 7 , 
 wherein said bonding margins at which said sheet material ends are made to overlap are brazed by supplying a brazing material that has been supplied to tube insertion hole formation surfaces of said tanks, further to said bonding margins through capillary action.    
   
   
       16 . A heat exchanger according to  claim 15 , 
 wherein said heat exchange tubes are stacked so as to alternate with outer fins; and    wherein said outer fins and edges of contact surfaces of said tube bonding margins are not in contact with each other.    
   
   
       17 . A heat exchanger according to  claim 15 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to tube insertion hole formation surfaces of said tanks by attaching brazing sheets to, at least, side surfaces of said tanks where said tanks are conjoined with said tubes.    
   
   
       18 . A heat exchanger according to  claim 15 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to side surfaces of said tanks at which said tanks are conjoined with said tubes, by spraying said brazing material at least onto tube insertion hole formation surfaces.    
   
   
       19 . A heat exchanger according to  claim 7 , 
 wherein said heat exchange tubes are stacked so as to alternate with outer fins; and    wherein said outer fins and edges of contact surfaces of said tube bonding margins are not in contact with each other.    
   
   
       20 . A heat exchanger according to  claim 7 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to tube insertion hole formation surfaces of said tanks by attaching brazing sheets to, at least, side surfaces of said tanks where said tanks are conjoined with said tubes.    
   
   
       21 . A heat exchanger according to  claim 7 , 
 wherein said tanks are formed through extrusion molding; and    wherein said brazing material is supplied to side surfaces of said tanks at which said tanks are conjoined with said tubes, by spraying said brazing material at least onto tube insertion hole formation surfaces.