Influence of tooth flank modification on tooth surface damage of conical involute gears

The conical involute gears have been applied to automotive parts such as 4WD transfer. The conical gear pair has characteristic large ease-off and this is equivalent to meshing of cylindrical gears which has large crowning for lead direction. Consequently, the trochoidal interference is thought to be caused because of tooth stiffness reduction. In this study, to clarify the influence of the tooth flank modification on the tooth surface damage, tooth surface endurance test with several tooth flank modification forms is experimented. As a result, the gear pair with crowning for tooth profile direction and reverse crowning for lead direction can extend the pitting fatigue life because of the edge load reduction of tip or root.