０　引　言气门芯等小型轴类零件的生产批量很大，其外圆等工序的加工是在车床上用两头顶来加工，零件的两头顶依靠车头和尾架两处顶尖来实现。普通尾架在卸下工件时，先松开锁紧手柄，转动尾架后手轮，卸下工件；装上工件时，转动尾架后手轮顶紧工件，再拧紧锁紧手柄。这种装 0 Introduction Valve core and other small shaft parts production volume is large, the processing of its cylindrical and other processes are used in the lathe with two top processing, parts of the two top rely on the front and tailstock two top to achieve. Ordinary tailstock in the removal of the workpiece, the first release of the lock handle, turn the tailstock after the hand wheel, remove the workpiece; mounted on the workpiece, turn the tailstock after the wheel handle the top tight workpiece, and then tighten the lock handle. This equipment