Abstract
There is a great need of a gear with a heavy load carrying capacity in order to size down an automobile transmission. For this need, conventional methods, which are improvement of a gear material and/or a heat treatment, have already achieved to the limit of development. Recently, a shot peening process, which can improve the bending fatigue strength of the tooth root, has been applied to some gears. However, as a result, the shot peening process applied to a gear surface has relatively decreased the surface durability, and the improvement of surface roughness become to require. Then, the author proposed to utilize a barreling process for improvement of the surface roughness. It was clarified that the shot peening and barreling processes are very superior ones to improve the load carrying capacity of a gear.
