Research On Non-backlash Gear Transmission And Controllable Gear Pair

With the development of science and technology, the performance of mechanical equipment is increasingly needed to be high. The transmission mechanism as an important component of the mechanical system, its performance directly affects the performance of the entire mechanical system. Gear transmission is the most widely used in mechanical transmission, thereby increasing the transmission precision, transmission efficiency and transmission smoothness of the gears, reducing or even eliminating transmission noise and vibration, achieving a smooth transmission control, is extremely important.In order to improve transmission performance of the precision gear pair under biaxial loading, backlash of the gear pair is eliminated in this paper. According to the condition, performance and size requirements of the gear pair, the structure to coordinate gap and size parameters are determined. APDL program of finite element software ANSYS is used to establish accurate parametric gear model. Tooth backlash clearance and tooth surface contact stress under different preload are analyzed by contact analysis module of ANSYS. The result with the change of preload is plotted. The preload under constant torque is determined. Influences of central distance deviation, parallelism of the axis plane and vertical plane on contact stress are also analyzed. Modal analysis of the gear pair is carried out by ANSYS modal analysis module. Former ten natural frequencies and modal shapes are obtained. Impact of preload on mode is also analyzed.It is can be founded from the analyzed results that when the gear pair clockwise rotates, a small preload can eliminate the backlash; when the gear pair anticlockwise rotates, a larger preload is needed to eliminate the backlash. Center distance deviation will change the coincidence degree of the gear pair. Positive deviation hardly affects the contact stress, and negative deviation can improve the load distribution between teeth. Parallelism deviation induce bias load between the gear pair, which result in uneven distribution of the contact stress and unstable gear transmission.The contact analysis results can be used to determine the assembly tolerance. Natural frequencies and mode shapes acquired by modal analysis are useful for determining the operating frequency of the gears. All the research results have an important guidance for smooth and controllable gear transmission.