陀螺框架轴承摩擦力矩分析

Analysis of Friction Moment of Gyroscope Frame Bearing

针对陀螺框架轴承要求启动摩擦力矩小而稳定的苛刻要求,建立轴承摩擦力矩分析模型,在已有的球与内外圈弹性滞后、差动、自旋、润滑影响因素引起的摩擦力矩分析基础上,重点考虑浪形及冠型保持架引起的摩擦力矩。求得的轴承启动、动态摩擦力矩与YZC-II测试仪测试结果吻合较好。分析表明,浪形保持架整体优于冠型保持架,保持架与球作用引起的摩擦力矩比例随轴向载荷减小而增大,该比重在启动过程中较大,在动态过程明显降低;通过对4种型号框架轴承不同转速的摩擦力矩分析,当转速低于2 r/min时,轴承摩擦力矩受转速影响不大,随着速度增大,启动速度对轴承启动摩擦力矩值、动态摩擦力矩波动范围影响突显出来。

For the applications of demanding small and stable friction moment of gyroscope frame bearings, the model of bearing＇s friction moment is built. Based on the existing analyses that include the friction moments caused by elastic hysteresis, sliding due to the contact race curvature, pivoting between the ball and the inner/outer race and lubrication, the friction moment caused by ribbon or crown cage are mainly introduced. Through comparing the calculated bearing＇s starting and kinematic friction moment to the experimental results measured by YZC-II tester, an acceptable consistent is achieved. The analyses show that the proportion of friction moment caused by cage increases with the decreasing loads. This proportion is larger in the bearing＇s starting friction moment and smaller in the kinematic friction moment. According to the calculated results of 4 kinds of frame bearings at different speeds, the speed has little influence on the friction moment when the bearings work at lower 2 r/min, but when the speed increases, it will have a big influence on the value of starting friction moment and the fluctuation range of kinematic friction moment.