Transmission Design And Characteristic Analysis Of Helical Curve-face Gear

The helical curve-face gear is put forward based on the straight curve-face. It is a kind of new non-standard gear by changing the tooth profile of straight curve-face gear. The helical curve-face gear combines the characteristics of the curve-face gear and the helical gear. It can be able to transfer the variable power and motion under the conditions of low speed and the overloaded, and it has the characteristics of simpler structure and lighter weight. Therefore, it has potential applications in the fields of engineering machinery, agricultural textile machinery, hydraulic machinery and automotive. This issue comes from the Natural Science Foundation of China “Design theory and manufacturing technology of fluctuating gear ratio face gear”(NO.5125537), the detailed research contents are listed as follow.According to the spatial meshing theory and differential geometry theory, the meshing transmission model of helical curve-face gear was established, and the equation of coordinate conversion, the pitch curve, addendum line and dedendum line were deduced. The trajectory of the shape cutter was studied, and the generation of helical curve-face gear can be built. According to the theory of tooth conjugate, the meshing equation and the tooth surface equation of helical curve-face gear were obtained. At the same time, the range of tooth width of the helical curve-face gear with no undercutting and tip-cutting conditions were analyzed. As well as the calculation method of pressure angle of the helical curve-face gear was studied.In accordance with the mathematical model of the helical curve-face gear pair, the influence law of the pressure angle, output speed and output angular acceleration affected by the parameters(such as the helix angle, the order of helical non-circular gear, the eccentricity and the order of helical curve-face gear) wear analyzed. Meanwhile, the calculation method of the contact ratio was proposed and the influence law of the contact ratio was obtained.Based on the theory of numerical solution, the numerical calculation of tooth profile of helical curve-face gear was put forward. Thereby, the equations of parameters of arbitrary curve were deduced. And the normal equidistant curves of the pitch curve of helical curve-face gear were established. Furthermore, through the comparative analysis between the theoretical calculations and the actual measurements, the correctness of numerical calculation was demonstrated. And the numerical calculation of tooth profile was programed by the VB and Matlab.On the basis of the modern processing techniques and testing methods, the manufacture of the helical curve-face gear pair was analyzed. Thereby, the measurements experiment and rolling test were studied. Then the tooth relative error and the meshing situation were obtained. By building the transmission test platform, the transmission ratio curve and output speed curve were proved. So the correctness of design methods and principles of helical curve-face gear were confirmed. It not only lays the theoretical foundation for the subsequent study, but also provides experimental data for the practical application of engineering.