Study on New Profile High Speed Roller Chain Sprocket
|Course||Mechanical Manufacturing and Automation|
|Keywords||Roller Chain Sprocket wheel Short Epicycloid Multi-body dynamics|
Roller chain is an important machine parts, widely used in automobile engines, petrochemical, auto assembly line machinery, especially in heavy, large center distance conditions, many industries have become the preferred form of transmission . However, with the continuous improvement of the transmission speed, the traditional roller chain sprocket tooth is difficult to adapt to high-speed, low noise, and other conditions of the transmission, the lack of the necessary theoretical support and technical support, the current domestic demand for new types of sprockets Toothed research is still in its infancy, has been dependent on foreign imports of high-priced chains. Therefore, the urgent need to study the new roller chain sprocket to improve transmission performance organization. Firstly, the paper analyzes the chain drive polygon mesh impact effect and the formation mechanism. To reduce the amount of fluctuation in the chain, reducing the chain drive mechanism at high speed when the chain and sprocket meshing impact and improve the smoothness of the chain drive, engaging the sprocket tooth profile design of the new study. Since short Epicycloid no singular point, there is no point of intersection with the base circle and the transition is smooth, so use short Epicycloid as a new sprocket tooth. Secondly, based on the short Epicycloid formation mechanism, short Epicycloid deduced equations, and use parametric equations seek offset curves were obtained for short Epicycloid sprocket tooth profile equation. Three-dimensional modeling techniques, the establishment of short Epicycloid sprockets, involute sprockets, sprocket and Epicycloid two standard sprocket (DIN8196 and GB1244-85) three-dimensional model, and use MATLAB calculated for each sprocket tooth profile data. Finally, the use of multi-body dynamics simulation software, based on the actual working conditions, the establishment of a timing chain drive mechanism multibody dynamics model for dynamic simulation, and the results were analyzed. The calculation of each tooth MATLAB data (involute, short Epicycloid tooth, tooth and standard tooth Epicycloid) entered into the model, in 1000-8000r/min different speeds of several Toothed simulation experiment. Comparative analysis of involute sprockets, short Epicycloid sprocket, standard sprocket Epicycloid sprocket and chain at different speeds fluctuations in the amount of friction between the chain and transmission parts, chain tension, sprocket and roll Son meshing impact and the speed of the driven wheel uneven coefficient. Simulation results show that, compared to involute sprocket sprocket and Epicycloid short Epicycloid sprocket sprocket angular velocity fluctuations can be reduced, the chain and the chain tension peaks as well as friction between the peak transmission parts; relative to the standard sprockets, sprocket short Epicycloid in a variety of speeds has more superior performance, can effectively improve the smoothness of the chain drive and dynamic performance.