The Influence of the Angular Coordinate of a Fixed Gear Wheel on the Kinematic Error of a Harmonic Drive

When designing harmonic drives, it is important to address the issue of reducing the kinematic error of the drive occurring due to the deformation of the flexible gear, radial oscillations of the cam, manufacturing and installation errors of the gears. Conventionally, this problem is solved by increasing the accuracy class of the gears and the parts where manufacturing errors impact the accuracy of cam installation. A mathematical model is proposed that enables researchers to study the dependency of the kinematic error of the harmonic drive on various factors already at the design stage. Calculation techniques are developed that take into account elastic interaction between the main elements of the drive as well as manufacturing and installation errors. The results of theoretical studies of the influence of the angular position of the flexible and rigid gears on the kinematic error of a harmonic drive with a cam wave generator are presented. The possibility of reducing the kinematic error by turning the fixed gear is proven.

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