新型车削平面机床运动机理

DYNAMIC MECHANISM OF NEW TYPE OF NC LATHES FOR MACHINING PLANE

探讨了一种新型车削平面运动机床的运动机理,即定轴轮系的旋轮线原理。首先建立了定轴轮系旋轮线的公式,在此过程中先应用坐标变换方法推导出了简单定轴轮系旋轮线的方程,并利用计算机画出了一些典型图形, 研究了旋轮线的性质、形状与传动比、尺度参数和初始角的关系。再根据定轴轮系的传动性质,建立了一般定轴轮系的旋轮线方程。然后利用点的速度合成定理推导出车削平面传动比方程,利用切削过程的对称性得出了一个旋转周期内工件和刀具的转速比。最后,对车削平面传动比方程进行了仿真,绘出切削过程中刀尖在工件上的轨迹和整个周期中刀尖在工件所固结的坐标系中的轨迹,所得结果验证了传动比公式。

The dynamic mechanism of a new type of machine tools for machining plane is discussed, which is the roulettes of the fixed axis gear train. The locus equation of the roulettes of the fixed axis gear train is built, and their application in machining plane is discussed. The locus equation of the roulette of the simple fixed axis gear train is derived by transforming coordinates first, and some typical figures are demonstrated by computer, The relations between characters and forms of the roulettes and the transmission ratios, mechanism parameter and the original phase angles are investigated. Then the equation of the complicated fixed axis gear trains is set up according to the transmission characters of the fixed axis gear trains. Then the equation of transmission ratio for machining plane is deduced by using the referred information, and based on the equation, the equation of transmission ratio for the whole rotating period is deduced by using the symmetrical property of the machining process. At last, an example is given to simulate the machining process, and the knifepoint locus on the workpiece and its locus on the coordinates system fixed on the workpiece is shown. The results testify above transmission ratios equations.