顶置凸轮-圆弧底摇臂混合润滑特性与磨损分析

通过对一种常用顶置凸轮摇臂机构运动学和动力学的分析，运用弹性流体动力润滑理论计算出该机构凸轮表面最小油膜厚度的分布状况，分析了凸轮－摇臂摩擦副的润滑特性。结合摩擦学理论给出了该机构凸轮表面磨损速率公式，计算结果与磨损试验数据进行比较，取得了较好的一致性。分析表明：处于混合润滑状态的顶置凸轮磨损速率主要与发动机缸头热负荷、凸轮表面工作应力、摩擦表面滑移量有关。工程设计中，提高摩擦表面粗糙度是改善磨损状况最简便的途径之一。

Overhead Camshaft-Circular Base Rock Arm Mixed Lubrication Properties and Wear Analysis

Based on the kinematic and kinetic analysis of a normal kind of OHC (overhead camshaft),the oil film minimal thickness distribution on the surface of camshaft is calculated and lubrication property is analyzed according to the EHL (elasto hydrodynamic lubrication) theory in this paper.The friction wear equation on the above mentioned camshaft surface is acquired on the basis of friction theory,comparison of the calculation results with the experimental data shows that the agreement is considerably satisfactory.It is concluded that engine head thermal load,camshaft surface working stress,friction face sliding length are the three most important elements to the friction wear in mixed lubrication.In engineering design,roughness improving is one of the most easy ways to reform the wear condition.