| Harmonic Drive has many merits such as small size, light weight, high precision, high rigidity, large transmission ratio, etc., the developed countries have successfully the harmonic gear transmission used in aerospace, radar systems, robotics and other fields, although researchers around the world study on harmonic drive with varying degrees, with the rapid development of aerospace, advanced manufacturing, robotics and other fields and "China wisdom made", "China manufacturing 2025 plan" project was proposed, puts forward higher requirements for the advanced harmonic gear drive. Therefore, analysis and research on the motion law of harmonic gear reducer from the meshing theory, analysis of harmonic reducer core components deformation of flexspline, the contact stress problem is particularly important, the study for the follow-up of harmonic reducer optimization, manufacturing high performance harmonic drive system to provide theoretical support.The harmonic reducer designed with subject was taken for the study. At first, an overview of the theoretical analysis of the structural characteristics and the basic principles of the harmonic reducer, the design of the project required the harmonic reducer followed, three-dimensional model of harmonic reducer was established use SolidWorks, analysis harmonic reducer flexspline deformation rules and inherent characteristics based on Ansys Workbench; and then from the theory, deformation of flexspline and bending stress was analysed and calculation by MATLAB, Finally according to the design of the harmonic reducer processing in kind for the experimental analysis.The main results of the paper are as follows:(1) According to the transmission ratio and size requirements of the design harmonic reducer, check the main parts material, life, wear resistance to achieve the requirements;(2) The calculation formula of the bending stress and deformation of the flexspline of harmonic reducer was presented by using the theory, and then analyze the influence of different parameters. The results show that increasing the mesh of the teeth can reduce the bending stress of the flexspline, and increase the maximum radial deformation leads flexspline bending stress increases; meshing teeth, the wall thickness of the flexspline on a smaller amount of flexspline deformation, maximum radial deformation directly determines the size of the deformed flexspline;(3) By comparing results Ansys Workbench analysis flexspline deformation and contact stress analysis and the theoretical calculation showed that because only considered as neutral layer deformation leads to the results of theoretical calculation is smaller, but flexspline deformation law and stress distribution results are almost identical, and show that the accuracy of the finite element analysis; At the same time the different parameters of flexspline torsional stiffness and fatigue life analysis. The results show that the maximum radial displacement decreases, the wall thickness and ratio of length to diameter decrease can increase the torsional stiffness; and the maximum radial displacement and the wall thickness increase, ratio of length to diameter reduced the flexspline in operation in the process of contact stress increases, eventually leading to reduction of fatigue life of flexspline. After modification of the flexspline should stress distribution is more uniform and the increase of fatigue life of flexspline.(4) The orthogonal test results show that the radial deformation of the flexible wheel has the greatest influence on the torsional stiffness and fatigue life of the flexible wheel, and the wall thickness and the length diameter ratio are the second;(5) Comparison with experimental modal and finite element analysis results, the results of both has a high degree of agreement; design harmonic reducer resonance phenomenon does not occur within the normal operating range; harmonic reducer drive performance tests found reducer has good transmission accuracy and high transmission efficiency. |
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