压电式振动辅助攻丝装置

在攻丝过程中，丝锥所受的扭矩会随着丝锥的进给而增加．扭矩过大会导致丝锥的断裂．为了解决丝锥的断裂问题，设计了一种辅助攻丝装置．该装置由一个弹性变形框架和一个压电元件组成．它能将压电元件的直线往复运动转化成丝锥的螺旋往复运动，模仿手工攻丝过程中的前妙后退交替运动，只是往复运动的频率很高．该辅助攻丝装置被装夹到一台立式铣床上进行了攻丝实验．实验结果显示，使用辅助攻丝装置能够明显降低攻丝扭矩．文中对攻丝扭矩进行了理论探讨并对扭矩与攻丝过程参数的相互关系进行了分析研究．辅助攻丝装置还能够用于其他加工过程，例如钻削、铣削等，可减小加工力，提高加工效率．

Vibration-Assisted Tapping with Piezoelectric Actuation

In a tapping process, as tap engagement increases, tapping torque increases accordingly, which may cause breakage to the tap. To solve this problem, a unique tapping device is designed that can actuate the tap in screw-type vibration during tapping. The device consists of a flexural frame and a piezoelectric actuator. The frame converts the linear motion of the actuator into screw-type motion of the tap to mimic the hand-tapping operation-forward/backward motions. The tapping device is used on a vertical milling machine for tapping experiments. Meanwhile, theoretical analysis is carried out to predict tapping torque for the tapping process assisted with screw-type actuation. A discussion is provided on how the tapping process parameters affect tapping torques. The results show that with the unique tapping device, tapping torque reduction is significant. The device can potentially be applied to other operations, such as drilling and milling, for machining force reduction and productivity enhancement.