Heat exchanger of aluminum

Claim 1

A heat exchanger made of aluminum, wherein a plurality of first plates of an aluminum-alloy and a plurality of second plates of an aluminum-alloy are stacked alternately in the direction along the thickness thereof and integrally brazed to each other, said heat exchanger comprising: a plurality of first plate members each having a three-layer structure as said first plates, each of said first plate members including a first core member of an aluminum-alloy, a first sacrificing material layer clad on one end surface of said first core member and having a lower corrosion resistance than said first core member, and a first brazing material layer clad on the other end surface of said first core member and having a lower melting point than said first core member; and a plurality of second plate members having a three-layer structure as said second plates, each of said second plate members including a second core member of an aluminum-alloy, a second brazing material layer clad on one end surface of said second core member and having a lower melting point than said second core member, and a second sacrificing material layer clad on the other end surface of said second core member and having a lower corrosion resistance than said second core member; said first plate members and said second plate members being arranged alternately with each other in the direction along the thickness thereof in such a manner that said first sacrificing material layer and said second sacrificing material layer are arranged in opposed relation to each other with a first fluid path interposed therebetween, and said brazing material layer and said second brazing material layer are arranged in opposed relation to each other with a second fluid path interposed therebetween; said first plate members each including a flat defining portion for defining said first fluid path and said second fluid path, a vertical wall portion located nearer to an outer periphery than said defining portion and bent in the direction orthogonal to the direction along the surface of said defining portion, and an outer edge portion bent in the direction along the surface of said defining portion from a forward end of said vertical wall portion, the surface of said outer edge portion being in contact with the joint between first plate member and said second plate member at least through said first brazing material layer, said vertical wall portion having a length longer than the distance between said defining portion and said second plate member.