Heat exchanger

Abstract

A heat exchanger includes plural laminated tubes through which a coolant from a fuel cell flows, fins arranged between the tubes and at outermost sides in a lamination direction of the tubes, core plates connected to longitudinal end portions of the tubes, and tank members attached to the core plates to form tank spaces. The tubes are made of a first insulating material, and the fins and the core plates are bonded to the tubes by using metal parts provided separately from each other on surfaces of the tubes. In addition, a coating portion is coated with a second insulating material on surfaces of the core plates at least at an exposed position of the core plates and at positions around brazing portions of the core plate bonded to the tubes. Accordingly, the heat exchanger can be insulated from the fuel cell without using an electrical insulating liquid.

What is claimed is:  
     
         1 . A heat exchanger comprising: 
 a plurality of tubes through which a coolant from a fuel cell flows to perform heat exchange, the tubes being laminated in a lamination direction and made of a first insulating material;    a plurality of fins arranged between adjacent the tubes and outermost sides of the tubes in the lamination direction to be bonded to the tubes;    a core plate connected to one longitudinal end portion of each tube; and    a tank member made of resin, the tank member being attached to the core plate at a side opposite to the tubes with respect to the core plate, wherein the tank member and the core plate are attached to form a tank space communicating with the tubes, wherein:    the tubes have a plurality of metal parts separated from each other on outer surfaces of the tubes; and    the fins and the core plate are bonded by brazing to the outer surfaces of the tubes at the metal parts.    
     
     
         2 . The heat exchanger according to  claim 1 , further comprising a coating portion coated by a second insulating material on one surface of the core plate opposite to the tank space wherein: 
 the core plate has an exposed portion exposed to outside from the tubes, and brazing portions brazed to the tubes; and    the coating portion is provided at least on the exposed portion and at positions around the brazing portions of the core plate.    
     
     
         3 . The heat exchanger according to  claim 2 , further comprising 
 first and second side plates arranged at the outermost fins in the lamination direction for reinforcing to extend in a longitudinal direction of the tubes, wherein:    at least one longitudinal end portion of each side plate is made of the first insulating material;    the one longitudinal end portion of each side plate has a brazing portion brazed to the core plate through a metal part provided on a surface of the longitudinal end portion of each side plate; and    the coating portion is provided on the core plate at a position around the brazing portion of each side plate.    
     
     
         4 . The heat exchanger according to  claim 1 , further comprising 
 first and second side plates arranged at the outermost fins in the lamination direction for reinforcing to extend in a longitudinal direction of the tubes, wherein:    at least one longitudinal end portion of each side plate is made of the first insulating material;    the one longitudinal end portion of each side plate has a brazing portion brazed to the core plate through a metal part provided on a surface of the longitudinal end portion of each side plate; and    the brazing portion of the longitudinal end portion of each side plate is separated from positions where the tubes are brazed to the core plate.    
     
     
         5 . The heat exchanger according to  claim 1 , further comprising 
 first and second side plates arranged at the outermost fins in the lamination direction for reinforcing to extend in a longitudinal direction of the tubes, wherein:    all the side plates are made of the first insulating material; and    each of the side plates further has a first metal part provided on its surface to be bonded to the outermost fin, and a second metal part provided separately from the first metal part on its surface to be bonded to the core plate.    
     
     
         6 . A heat exchanger comprising: 
 a plurality of tubes through which a coolant from a fuel cell flows to perform heat exchange, the tubes being laminated in a lamination direction and made of a first insulating material;    a plurality of fins arranged between adjacent the tubes and outermost sides of the tubes in the lamination direction to be bonded to the tubes;    a core plate connected to one longitudinal end portion of each tube;    a tank member made of resin, the tank member being attached to the core plate at a side opposite to the tubes with respect to the core plate, wherein the tank member and the core plate are attached to form a tank space communicating with the tubes;    a plurality of first metal parts provided on outer surfaces of the tubes to be bonded to the fins; and    a plurality of second metal parts provided on the outer surfaces of the tubes to be bonded to the core plate, wherein the second metal parts are provided on the outer surfaces of the tubes to be separated from the first metal parts.    
     
     
         7 . The heat exchanger according to  claim 6 , wherein: 
 the first metal parts are provided on the outer surfaces of the tubes to be separated from each other; and    the second metal parts are provided on the outer surfaces of the tubes to be separated from each other.    
     
     
         8 . The heat exchanger according to  claim 6 , wherein the first metal part and the second metal part are provided on the surface of each tube to cover a part of the outer surface of each tube and to have an uncovered part between the second metal part and the first metal part.  
     
     
         9 . A heat exchanger comprising: 
 a plurality of tubes through which a coolant from a fuel cell flows to perform heat exchange, the tubes being laminated in a lamination direction and made of a first insulating material;    a plurality of fins arranged between adjacent the tubes and outermost sides of the tubes in the lamination direction to be bonded to the tubes;    a core plate connected to one longitudinal end portion of each tube;    a tank member made of resin, the tank member being attached to the core plate at a side opposite to the tubes with respect to the core plate, wherein the tank member and the core plate are attached to form a tank space communicating with the tubes;    a first metal part provided on an outer surface of each tube to be bonded to the fins; and    a second metal part provided on the outer surface of each tube to be bonded to the core plate to have an uncovered part on the surface of each tube between the second metal part and the first metal part.    
     
     
         10 . The heat exchanger according to  claim 1 , wherein the first insulating material is a ceramic material.  
     
     
         11 . The heat exchanger according to  claim 1 , wherein the core plate and the fins are made of a metal material.  
     
     
         12 . The heat exchanger according to  claim 1 , wherein the tank member and the core plate are arranged at both the longitudinal end portions of each tube to form the tank space at two longitudinal sides of the tubes.