Form Rolling of Helical Gear with Small Number of Teeth and Large Helix Angle Effect of die penetration rate on tooth trace deviation

摘要

Form rolling of helical gears having two teeth and large helix angles was performed in order for applications in automobiles. However, large form deviations were observed in these gears. In the present paper, the generation mechanism of the form deviations was discussed. At first, the pitch surface of the form rolled gear was assumed to be a circular cone, which has a height equal to the axial pitch of the form rolled gear. Generated gear flanks were geometrically analyzed to investigate the effect of die penetration rate on tooth trace deviations, in which periodical fluctuations were recognized. Experiments were also performed to verify the calculated results. As a result we found that the die penetration rate can effect the tooth trace deviations.