Studying the backlash of wave gears with external wave generators

Wave gears with external wave generators represent a particular type of wave gears providing high-precision electromechanical drives. Kinematic errors in such wave gears are minimal due to multi-zone and multi-pair tooth engagement and a specific form of gaps between the teeth before and after engaging. This study evaluates the influence of the geometric parameters of tooth engagement, that is, the radial deformation of the flexible wheel along the minor axis of the deformation curve w0, engagement angle aw, and contact angle b on the backlash. The results of research improve the knowledge about the benefits of these wave gears over those with internal deformation and make it possible to design high-precision wave gears. Formulas for calculating the backlash are presented. The initial and final engagement angles are determined.

References

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