Study On Kinematics Of Internal Parallel Moving Gears Transmission

Internal parallel moving gears transmission is a special kind of planetary gear train with a small tooth difference, the mechanism was developed on the basis of the principle of parallel crank and the theory of planetary transmission. Comparing with gear transmission with axis fixed and planetary transmission, the mechanism has a lot of merits, such as compact structure, large transmission ratio, and large transmission capacity within unit weight and so on. It can be widely applied in many fields, such as vehicle engineering, heavy equipment, aerospace and military equipment. Therefore, internal parallel moving gears transmission has a good application prospects. But the study of the transmission form is just beginning, and hasn't been developed a sound design method, especially the option of working pressure angle and modification coefficient is always a big problem which lays restraints on the theory research and application promotion of internal parallel moving gears. The problem is so urgent that it must be solved immediately.Regarding internal parallel moving gears transmission device as the target of study, and the field of research is kinematics of internal parallel moving gears transmission. The design formulas of kinematics and geometric parameter constrains, and optimal option of geometric parameter, etc. are studied in depth. Taking advantage of the technology of virtual assembling and kinematics simulation, and combing a design instance, the interference check method is developed. After cooperation and analysis, the DIN formula is selected as the design formula of internal parallel moving gears transmission, and solved the problem that the design formulas are inconsistent and arbitrary. In the premise of no interference, by means of software MATLAB, the feasible region of geometer parameter is proposed and the relationships of main geometer parameters are analyzed, which provides theoretical basis for improving of kinematics design. In order to enhance the engaging efficiency and load capacity, the optimization model of minimum working pressure angle and minimum modification coefficient are built with the help of mechanical optimization method, and the solve method of optimization model is developed on the basis of software LINGO. According to the characters of internal parallel moving transmission that the path of contact is variable and more than one tooth contacts, the calculation method of contact ratio and continuous transmission conditions are researched in the aspects of line contact ratio and angle contact ration. Combing a practical design instance and the formulas and optimization model provided in this paper, a set of optimized parameters are obtained, with the parameters the solid model and assemble model are built on the basis of software PRO/ENGINEER, and actual linkage relationships and contact pairs are built. In addition, with the help of kinemics simulation technology, the virtual movement of assemble model is simulated, and static and dynamic interference are checked. This method can verify whether the design is reasonable, which puts forward a way to estimate the design results.The graphics and formulas that illustrates the relationships of geometer parameter, and optimization models and relevant optimization programs, and the technology of virtual assemble and kinematics simulation, have great practical and instructive significance, which can improve design quality and shorten design cycle.