Strain wave gearing with involute positive deflection tooth profile taking rim thickness into consideration

摘要

In the strain wave gearing, an involute positive deflection tooth profile of a low pressure angle of less than 20° is used as the basic tooth profile for the rigid internal spur gear and the flexible external spur gear in order to increase the effective tooth depth. Continuous meshing of the two gears in the tooth trace direction is made possible by shifting the external teeth so that the linear parts of the rack tooth profiles coincide when viewed along the tooth trace direction. The root rim thickness of the front end of the external teeth of the flexible external spur gear is set to an optimal thickness and the root rim thicknesses at various positions other than the front end of the external teeth in the tooth trace direction are set to appropriate values.