支承刚度及齿面涂层对斜齿轮副啮合特性的影响研究

Study on the influence of support stiffness and tooth surface coating on the meshing characteristics of helical gear pair

支承刚度对自动变速器齿轮副的啮合质量有着重要影响,研究支承刚度及齿面涂层对斜齿轮副啮合特性的影响具有重要意义。以某七挡双离合自动变速器的一挡斜齿轮副为研究对象,建立了2种不同支承刚度的齿轴系统刚柔耦合模型,分析了不同工况下支承刚度对斜齿轮副啮合特性的影响规律;通过FCL-250H齿轮精测试验台得到有/无磷酸锰转化涂层齿轮的齿形齿向参数,并将其代入有限元模型进行仿真分析;进行齿轮接触疲劳点蚀实验,对比齿面涂层处理前后齿轮的接触疲劳寿命,并从齿轮表面形貌、动力性能及跑合性能等角度进一步揭示了涂层的强化机理。研究结果表明:齿轴跨度增大,支承刚度减小,则齿轮单位长度所受最大载荷和啮合错位量对输入扭矩的变化更为敏感;有涂层齿轮跑合后更有利于啮合,其疲劳寿命得到提高。研究结果为汽车自动变速器齿轮传动系统的结构优化和齿轮疲劳寿命的提高提供了参考。

Support stiffness has an important influence on the meshing quality of the gear pair of automatic transmission. It is of great significance to study the influence of the support stiffness and the tooth surface coating on the meshing characteristics of the helical gear pair. Taking the first helical gear pair of a seven-shift double-clutch automatic transmission as the research object, two rigid-flexible coupling models of the gear shaft system with different support stiffness were established, and the influence of the support stiffness on the meshing characteristics of the helical gear pair under different working conditions was analyzed;the tooth profile and tooth direction parameters of the gear with/without manganese phosphate conversion coating were obtained through the FCL-250H gear precision test bench, and were substituted into the finite element model for simulation analysis;the gear contact fatigue pitting test was carried out to compare the contact fatigue life of the gear before and after the coating treatment, and the strengthening mechanism of the coating was further revealed from the aspects of the gear surface morphology, dynamic performance and running-in performance. The results showed that the support stiffness decreased with the increase of gear shaft span, and the maximum load per unit length of gear and the amount of meshing dislocation were more sensitive to input torque changes;after running-in, the gear with coating was more conducive to meshing, and its fatigue life was improved. The research results provide a reference for the structural optimization of the gear transmission system of automotive automatic transmission and the improvement of the gear fatigue life.