| 摘要 |
PROBLEM TO BE SOLVED: To provide a flat heat exchange tube which is composed to be tube-expandable despite the tube brazing a corrugated inner fin, tightly contacts a PTC heater or the like and can improve a heat transfer coefficient by reducing a contact thermal resistance, and to provide a heat medium heating device and an air conditioner for vehicle using the device.SOLUTION: A flat heat exchange tube comprises a flat tube 22 comprising a pair of molding plates 22A and 22B, and the corrugated inner fins 23A and 23B which are inserted between the molding plates 22A and 22B and in which the protruding apexes 23C and 23D are brazed on the inner faces of one side and the other side of the pair of molding plates 22A and 22B, respectively. The corrugated inner fins 23A and 23B are provided with the tube expansion-allowable part 23E which allow the wall faces between both apexes 23C and 23D to deform in a direction in which the distance between the apexes 23C and 23D extends. Thereby, a flat heat exchange tube 14 is made to be expandable through the tube expansion-allowable part 23E in such a state that each of the apexes 23C and 23D ia brazed between the pair of molding plates 22A and 22B. |
