PURPOSE: To improve commercally required characteristics such as sealing performance and strength increasd beautifulness of the appearance by providing a groove on the outside circumference of the mating part of aluminum castings of torque converters and by plasma-welding said part.
CONSTITUTION: A groove is provided on the outside circumference of the mating part of the case of a torque converter using aluminum castings. Thence, the said groove part is welded by a conventional plasma welding method, wherein the direction of an electrode is so determined as to scatter electrons from the welded works to the electrode side. In this manner, the oxide films produced in the welding zone at high temperature are broken; therefore, the strength and sealing performance improve and the beads are finished to a smooth and beautiful appearance.
HIRANO TOSHIYUKI
KAZUTA HISASHI
