| 摘要 |
PURPOSE:To increase joint strength and to obtain a heat exchanger which does not clatter by upsetting the upper and lower positions of an assembly interposed with a flux in the midway of a stage for drying the flux interposed between the parts of the heat exchanger. CONSTITUTION:The assembly 3 formed by assembling Al corrugated fins 2 to an extruded flat perforated tube 1 made of Al is immersed into the flux contg. zinc halide; thereafter, the assembly 3 is taken out of the flux. Such assembly 3 is put into a furnace and the drying is started. The upper and lower positions of the assembly 3 are upset while the flux still retains flowability before its solidification. This state is then maintained for the same time as the time before the upsetting until the flux is dried and solidified. The atmosphere in the furnace is substituted with an inert gaseous atmosphere after the drying and the in-furnace temp. is maintained at a prescribed temp. to effect the reaction soldering for the prescribed time. Zinc is thereby deposited to the joint parts between the perforated tube 1 and the fins 1, etc., by which the tube 1 and the fins 2 are brazed. Such assembly is rinsed and the heat exchanger is obtd. |
