| 摘要 |
PURPOSE:To increase the mechanical connecting strength between a flat tube and a core plate by expanding the end of the flat tube of a heat exchanger in a tapered form. CONSTITUTION:With the lower core plate 1 engaged with a stopper 10a of a mount 10, pressing the upper end of a tube 2 downward by a press block 17 will cause a pipe expansion member 15 to protrude out of a through-hole 14 and the tip of the pipe expansion member 15 enters into the flat tube 2. After attaching one end of the flat tube 2 to a cylindrical projection 1a of the core plate 1 by expanding the tube, the core 6 is removed from the tube expansion device. Then, the core 6 is overturned and set on the tube expansion device to expand the other end of the flat tube 2. The core 6 which completed the tube expansion is heated in a vacuum oven in order to braze the flat tube 2, corrugated fin 2 and core plate 1. After the brazing is completed, a seal ring 22 is disposed around the core plate 1 and a tank member 5 is calked by the core plate 1 to connect the tank member 5 to the core 6 in a watertight manner to complete the radiator assembly. |
