Patent attributes
To provide a harmonic drive gearing with high degree of freedom in terms of layout. A harmonic drive gearing 10 includes a circular spline 1′, having outer teeth formed on an outer peripheral surface; an flexible spline 2, positioned at the outside of the circular spline 1′, and having inner teeth, which are engageable with the outer teeth of the circular spline 1′, formed on an inner peripheral surface; and a rotor 16 which is disposed at outside of the flexible spline 2 and serves as a wave generator, wherein the rotor 16 deflects the flexible spline 2 by minor axis portions of the inner peripheral surface of the flexible spline 2 and engages the inner teeth of the flex spline with the outer teeth of the circular spline 1′ and thereby the engagement position between the inner teeth and the outer teeth is adapted to move in a circumferential direction.
