Design and machining of the epicycloid planet gear of cycloid drives

This paper presents a mathematical model and design procedures to design the epicycloid planet gear of cycloid drives. It is based on coordinate transformation, envelope theory, and theories of conjugate surfaces, from which the equation of meshing is derived, while the path of machining tools is obtained by the equidistant curve principle. In addition, a program is developed to solve the equations of meshing and conjugate surfaces. Therefore, the epicycloid-profile is obtained. Then, these data are used to construct the 2D drawing and solid modeling of the epicycloid-planet-gear using AutoCAD and Pro/E (a CAD software package), respectively. The CAD data is used for machining, in this case by a wire-cutting machine. The manufactured component is presented to demonstrate that the design procedures and manufacturing are feasible. The design approach and machining method are suitable for applying CAD and CAM in industrial fields.

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