The Research On Toroidal Drive

This paper focuses on optimum design, meshing error theory, digital simulationand NC manufacturing for toroidal drive. The method of multi-objective optimum design aimed at the minimum volume ofthe reducer and minimum velocity between the meshing surface of the sun-worm andthe planet worm-gear for the toroidal drive is proposed and mathematical model forthe multi-objective optimum design of toroidal drive is developed. By solving theoptimum mathematical model, the optimum parameters for the toroidal drive hasbeen obtained. The mathematical modeling of meshing equations, tooth profile and tooth profilehelix equations of the sun-worm and the stationary internal toroidal gear aredeveloped. The principles and methods for accuracy modeling of the sun-worm andthe stationary internal gear are proposed. In Solidworks system, the 3D modeling andvirtual assemblyof the toroidal drive have been completed. In the Solidworks/DDM system, the kinematical and dynamical simulations of thevirtual prototype of toroidal drive are implemented. By kinematical simulation, theinterference of toroidal drive is verified and the accuracy of the toroidal movement isqualified. By dynamical simulation, the load bearing capacity and movementcharacteristics of the main elements of toroidal drive are obtained. In Solidworks system, based on the dynamical and kinematical simulation, thestresses, strains and displacements of the toroidal drive for the sun-worm, the planetworm-gear, the stationary internal toroidal gear and the spherical rollers areaccomplished by FEA method. The NC machining simulations of the sun-worm and the stationary internaltoroidal gear are implemented which provides approaches for the physical prototypemachining and for the designing of machining cutters. Considering the error exist in manufacturing and assembly of the toriodal drive,the meshing equations for the conjugating between the planet worm-gear and thesun-worm and between the planet worm-gear and the stationary internal toroidal gearare developed, further, the tooth surface equations, contact curve equations, toothprofile equations, helix equations, helix angle equations, two kinds of limit curve　 ＩＩequations and induced normal curvature equations are derived. Based on theabovementioned equations, the characteristics of the contact curves, the helix anglesand the induced normal curvatures have been presented by the impinging on of theseerrors. The NC machining principles of the sun-worm and the stationary internal toroidalgear are proposed. The machining of the sun-worm and the stationary internaltoroidal gear are completed. Finally, the assembly and tested of the physicalprototype are carried out.