中文摘要：

介绍了2种四点接触球轴承的摩擦力矩理论计算模型，采用不同模型计算同型号的轴承，对比分析可知，造成计算值差异的关键因素在于是否考虑轴承内部的几何结构参数。在考虑几何结构参数的计算模型中，影响最突出的是轴承实际接触角。还分析了加工精度对四点接触球轴承的实际接触角及其摩擦力矩的影响，并通过试验进行了验证。

英文摘要：

Two theoretical computing models for friction torque of four- point contact ball bearings are introduced. A specific four - point contact ball bearing is involved in the calculation according to different calculation methods and dif- ferent calculation values are obtained. The difference caused by different calculation methods lies in if geometrical pa- rameters are involved in calculation or not. In the model considering geometrical parameters, the most important factor that influences the calculation value of is actual contact angel. The influence of machining accuracy on actual contact angel and then on friction torque is analyzed. An additional friction torque model is established and specific test is de- signed to prove the theoretical analysis.