在生产中，我们需要加工一批如图 1所示的工件，在钻 18和精镗 35 孔时，需夹持螺纹 M16× 1.5处，这样极易将螺纹卡伤影响使用。用铜皮包裹螺纹处再夹紧，效果也不理想，而且定位精度降低。为此，我们设计了一种螺纹夹紧简易装置。 　　该夹具结构如图 2所示。使用时，将 In the production, we need to process a number of the workpiece as shown in Figure 1, drill hole 和 18 and fine boring  35 holes, the need to hold the thread M16 × 1.5 Department, so easy to use the thread card injury. Copper thread wrapped with copper and then clamped, the effect is not satisfactory, and reduced positioning accuracy. To this end, we designed a simple screw clamping device. The fixture structure shown in Figure 2. When used, will