........................ 22 3.2.3 伺服电机的选择.................................................................................................... 25 3.2.4 振动攻丝机滚珠丝杆副的预紧方式.................................................................... 27 4攻丝机的基本控制设计........................................................................................................... 29 结论............................................................................................................................................... 32 致谢............................................................................................................................................... 33 参考文献....................................................................................................................................... 34