A Calculating Model Study For The Elastohydro-dynamic Lubrication Of The Transmission Of The Gear In Mesh

During the transmission of the involute gear in mesh, the gear engagement stiffness, the load, the sliding velocity and the curvature are varying with the meshing line of the gear teeth. At the same time , because there are some manufacturing and install error and the like ,so the dynamic load inevitably produced .So we can say the transmission of a gear is a representative dynamic process, but the contact strength design which are used now are only applicable to the steady condition of the contact Hertz theory. Therefore, preceding the research of the elastohydro-dynamic lubrication of wheel gear for a perfect strength designing theories has the certain theories meaning. This study is based on a comprehensive method whichapplies dynamics and tribology to the analyses of the gear transmission system. The rotation and traverse vibration of six parts in the gear transmission system are studied in this paper. And then the author bring forward the elstohydro-dynamic lubrication theory match with the dynamic load of the gear, and at the last, developing a calculating model for the elastohydro-dynamic lubrication of the transmission of the gear in mesh. The establishment of the model is doubtless a stability base for the continuing research. Analysis, summarizing the textual main work, can induce as follows:1. The equivalent kinetics model and the dynamic equations of the rotation and traverse vibration of six parts in the gear transmission system are established in this paper. Calculates the static and dynamic gear engagement stiffness, analysis the influence of the tooth profile and pitch errors of gear to the gear engagement stiffness; and give out the distribution of the gear engagement stiffness and the dynamic loads of the gear along the meshing line of the gear teeth;2. Especially using the Simulink tool in the Matlabdeduces the systemic kinetic equations are features of the thesis. In the paper , adoption equivalent gear teeth form method analyzed the round flection of the gear teeth, in it conclude the bending and cutting distortion of rectangle and trapezoid two parts , the gear teeth and contact distortion come frome the slants of the gear teeth body, and so on .moreover give out the correspond distortion graph.3. Coupling the calculation results of the gear dynamic loads and the elastohydro-dynamic lubrication can form the gear wheel unsteady elastohydro-dynamic lubrication calculating formula. In this formula not only consider the heat effect of the lubricant but also the non-Newtonian effect, and also the changing of the loads, velocity and curvature with the time and the space. Applying this formula can calculate the stress distribution of gear teeth in meshing, the thickness of the film, distribution of the temperature and the coefficient of the friction, etc.4. The author put forward a calculating method for unsteady elastohydro-dynamic lubrication in gear transmissionsystem. Because the multi-grid method have a good numerical value stability and have a quick convergence, so these years many researchers interests on it, and so in this paper the author put forward the idea how to using the method for the calculating and the numerical value method. Because the restrict of time, I cannot get the numerical value results, this is just a pity of this paper. Carries out the numerical simulations of tooth profile and pitch errors of gear. This paper demonstrates that gear engagement stiffness has a primary influence; tooth errors mentioned above have a secondary influence on the vibration of the gear transmission system.