| abstract |
Air passages 18 are formed between surfaces of a plurality of heat transfer plates 12 laid together. A plurality of rib sections 14 extending orthogonal to the air flowing direction A are formed on a surface of the heat transfer plate 12 and projected into the air passage 18. By shifting the positions of the rib sections 14 to each other in the air flow direction, coolant passages 15, 16 are formed inside the plurality of rib sections 14. Between the plurality of rib sections 14, fin sections 17 are formed integral with the heat transfer plate 12 and projected from the plate surface. The fin section 17 has a protruded shape formed by pressing and having a cut portion partially cut a plate thickness of the heat transfer plate 2. |