Abstract
To reduce the starting torque, an internal-spherical precession motion rotor type of orthogonal output type precession motion ball reducer is developed. In this report, the motion loci of balls on that internal-spherical rotor are analyzed. This rotor generates the precession motion which is similar to the conventional one. And using the evaluation method of a pressure angle, it is confirmed that rotor drives the driven rotor by over two balls. Also, the balls on this rotor which are assigned on the input fixed rotor side can be assigned on the arbitrary positions.
