PLASTIC DEFORMATION MECHANISM OF HYPOID GEARS

抄録

Hypoid gears are used as the final reduction gear of vehicles to transmit and change direction torque. Plastic deformation of a hypoid gear tooth flank occurs when a load exceeding the yield stress acts on the tooth surface. This study analyzed the plastic deformation mechanism of hypoid gears. First, the relationship between plastic deformation and these stresses was identified by finite element analysis of approximated tooth contact. The results of this analysis found that local plastic deformation of the tooth flank is caused by Hertzian stress under the line of contact. Second, a plastic deformation index which was defined to simulate plastic deformation consists of three elements: 1) yield stress considering the hardness of a case-hardened gear, 2) Hertzian stress under the line of contact, and 3) a correction coefficient at the contact point. The correlation between the plastic deformation index and plastic deformation was confirmed by a deformation test.