Structural Design And Optimization Of Key Components Of Harmonic Drive Based On Assembly

Taking the SHF-30-2UH hat-type hollow shaft harmonic reducer as the object,based on the finite element method,orthogonal experiment method and response surface optimization method,the static characteristics of the assembly meshing model including wave generator,flexspline and rigid fear were investigated.The influence degree and law of different structural parameters of wave generator and flexspline on the stress of flexspline were explored.The natural frequency and mode shape of the deformed flexspline were studied.1.The flexspline was simplified as a cylindrical cylinder.Taking the intersection line between the flexspline and the face with long axis and the face with short axis of the wave generator as the breakthrough point,based on the theory of material mechanics,the variation trend of the deflection and bending moment of the flexspline cylinder was explored.The maximum deformation point and the weakness point of the flexspline in the assembly model were qualitatively put forward.And the first strength theory and the fourth strength theory were selected to further study the flexspline.2.Based on the influence of structural parameters of wave generator on the deformation of flexspline,a conic wave generator was proposed.Three-dimensional models of wave generator,flexspline and rigid gear were established respectively.According to the matching relationship of components,the assembly meshing model including flexspline,wave generator and rigid gear was established.Based on the finite element method,the static results of the assembly meshing model were obtained.According to the first strength theory and the fourth strength theory,the stress fields of assembly models with and without rigid gears were compared.The critical path of the flexspline and the deformation of the cylinder were analyzed,and the theoretical analysis was verified.The stress of each part of the flexspline was explored to provide direction for structural optimization.3.Based on the statics results of the assembly meshing model,with the maximum equivalent stress of the flexspline as the optimization objective,the structural parameters of the wave generator were extracted,and the structural parameters of the wave generator were optimized and analyzed by response surface optimization method.Then,for the assembly meshing model including the wave generator with the optimal parameters,the maximum equivalent stress of the flexspline was extracted as the objective,and the structural parameters of the flexspline were extracted.Based on response surface optimization method and orthogonal test method,the optimal structural parameters of flexspline were obtained.4.With the deformed flexspline as the core,the modal characteristics of the simplified flexspline,the complete flexspline and the assembly model were studied.The natural frequencies and mode shapes of the deformed flexspline and the undeformed flexspline were analyzed,and the modal characteristics which were closer to real harmonic drive were studied.