Method and apparatus for convection brazing of aluminum heat exchangers

A high velocity convection braze furnace assembly for brazing aluminum heat exchanger workparts in a controlled atmosphere, said assembly comprising:

• a substantially sealed housing defining a controlled atmosphere brazing chamber;
• heater means for elevating the atmospheric temperature within said housing;
• conveyer means having a planar workpart support surface for successively conveying workparts through said housing supported horizontally and above said support surface;
• an impeller having a suction inlet and a pressure outlet for convectively circulating the atmosphere at high velocity through the workpart;
• and atmosphere director means disposed within said housing between said pressure outlet of said impeller and said support surface of said conveyer means for directing the circulating atmosphere perpendicularly and downwardly toward said support surface so that the high velocity circulating atmosphere urges the workparts tightly down against said support surface to prevent lateral and torsional movement of the workparts on said support surface while concurrently rapidly heating said workparts.