To provide an inexpensive heat exchanger with high reliability with respect to coolant leakage to be used in a cooling apparatus using a coolant.
In a heat transfer tube 2, one tube body is meanderingly formed by bending wherein a straight tube part and bent tube parts position in both ends of the straight tube part are continuous. The bent tube parts are bent in the same direction in respective end parts, and obliquely in opposite directions with respect to mutually facing end parts. Through holes 3A provided in a tabular fin 3 are formed like long holes pierced by the bent tube part, and they are provided obliquely to be the same angle as the slanting of the bent tube part using a rim of the tabular fin 3 as a base line in a vertical or horizontal row state. By composing a coolant flowing portion of the heat exchanger 1 by the heat transfer tubes 2 obliquely arranged over two rows at a certain pitch with respect to a fin rim direction without seams, the heat exchanger 1 is inexpensive, and reliability is high with respect to coolant leakage.
Hiroki Naito
Daisuke Nagano