图1为袖珍手枪式环形槽内径测量仪。使用时,应预先用分厘卡调整到零件最小尺寸,并使千分表针对准零位。使用时,按压扳机5,不动爪2与动爪3彼此併拢,进入工件的沟槽内后,动爪与百分表的测量头接触。松开扳机时,动爪便在弹簧的作用下与被测工件表 Figure 1 pocket pistol ring groove diameter measuring instrument. When used, should be used in advance to adjust the minimum size card parts, and make the dial indicator aimed at zero. In use, the trigger 5 is pressed so that the claw 2 and the claw 3 are in close contact with each other. After entering the groove of the work piece, the claw is contacted with the measuring head of the dial indicator. When the trigger is released, the claw moves under the action of the spring and the workpiece under test