摆式飞剪是剪切机的一种,它用以剪切运行着的金属材料。它由具二活动度的平面连杆机构组成。本文用单位矢量法对其进行运动分析。在不同工作条件下,根据该机主轴曲柄与后轴曲柄在不同相位角时,通过计算机的计算,作出了相应的剪刃的速度线图。由图可以了解该机剪刃的速度变化规律,并能更好地了解该机构的工作特性。本文所采用的单位矢量分析法,亦适用于其它具二活动度的平面连杆机构的运动分析。 Pendulum flying shear is a kind of shear, it is used to shear the running metal material. It consists of a plane linkage with two degrees of freedom. This article uses the unit vector method to carry on the movement analysis to it. Under different working conditions, according to the machine crankshaft and rear axle crank at different phase angles, through the calculation of the computer, made the corresponding blade speed line graph. From the map you can understand the speed of the blade cutting edge of the law, and to better understand the working characteristics of the agency. The unit vector analysis method used in this paper is also suitable for the motion analysis of other planar linkage mechanisms with two degrees of freedom.