| 摘要 |
<p> The invention relates to a layered heat exchanger, for example, for use as a layered heat exchanger for motor vehicle coolers. To provide a turn portion in the heat exchanger for changing the direction of flow of a fluid which flows zigzag through a fluid circuit, a metal plate for fabricating the exchanger is provided at the upper end or the lower end of a partition ridge with a fluid flow direction changing passage forming caved portion having a bottom wall of circular-arc cross section. Front and rear upper tank portions of a flat tube portion or front and rear lower tank portions thereof are held in communication with each other through a fluid flow direction changing passage having an approximately circular cross section and formed by the caved portions which are opposed to each other. The turn portion is diminished in the concentration of stress thereon due to the fluid internal pressure and given an increased resistance to pressure to effectively prevent tank side walls from breaking, consequently making it possible to decrease the thickness of the metal plates for fabricating the heat exchanger, to achieve a cost reduction by the decreased thickness of plates and to assure an improved heat exchange efficiency.</p> |
