Study On Optimization Design Of Meshing Parameters And Transmission Error For Involute Harmonic Gear Transmission

Harmonic gear transmission has been developed with the space technology. Compared with a normal gear transmission, there are many advantages for the harmonic gear transmission, such as high transmission accuracy, large transmission ratio, small volume, light weight, high load carry capacity and so on. And now, the harmonic gear transmission has been widely used in space flight, robots, radars, machine tools, instruments, ship crafts, automobiles, weapons, medical apparatus etc. The thesis is based on the project of "Study on precise gear transmission device with super miniature volume". The project is requested to develop a harmonic gear transmission device with super miniature volume and high load carry capacity.However, for the domestic harmonic gear transmission devices, the process is backward, the kinematic accuracy and backlash are all greater than 6', the gear accuracy is 6～7 grade, the reliability is low also. So they can't satisfy the needs. The foreign technology is more mature, and the kinematic accuracy and return difference of the transmission device are less than 3', and the gear accuracy is 2～5 grade, reliability is high. But the advanced technology is blockaded and the products are expensive. So it is important that we develop our own high performance harmonic gear transmission devices.For domestic harmonic gear transmission devices, problems above are studied, the main contents are as follows.(1) Based on previous achievements, the tooth profile equation of flexspline and circular spline in all the meshing position, and the backlash formula of an involute harmonic gear are deduced.(2) The optimization design scheme aimed to acquire the optimal backlash is presented. The characters of the involute harmonic gear transmission with standard ellipse cam wave generator are analyzed and a mathematical model is established. Using the complex method, the solution of the mathematical model is got, and results have verified the feasibility of the scheme by examples.(3) The harmonic gear transmission errors are studied. Error source of causing errors and the mechanics of all the transmission errors are analyzed. The distribution of all the errors from the view of statistics is studied and the statistical expressions are deduced. At last, the transmission error formulas of thinking about the influence of malt-meshing are derived.(4) The experiment is carried out to get the performance parameters of the manufactured harmonic gear transmission devices; the parameters include transmission error and return difference. Contrasting the experiment results with the requests of the project, results indicate that the study of the theory is correct and rational.