提出了一种新型模态转换压电钻。该压电钻将钻头斜向安装在定子基体上,形成一个纵弯模态转换器。利用压电陶瓷的逆压电效应使定子基体产生纵向振动并通过纵弯模态转换器将该纵向振动转换成钻头部分的局部弯振,从而在钻头端部合成为椭圆运动,为切削及钻孔提供动力。利用有限元分析软件ANSYS对压电钻进行结构设计,仿真了钻头在设计工作频率下的切削轨迹。根据仿真结果试制了一台样机,对该样机进行了激光扫频实验,结果表明,样机工作频率为56kHz,切削频率可达336×104次/min,切削幅度则可控制在微米级。实验表明该样机配上普通牙钻,可在普通打印纸、硬纸板、铝板、钢板上进行切削、钻孔等操作。
A new type of mode convert piezoelectric drill was presented.The drill was fixed on the base of the stator with an angle to form a longitudinal-bending vibration converter.By using the converse piezoelectric effect to exciting the longitudinal vibration of the stator base,the converter would convert the longitudinal vibration to bending the vibration partially.These two vibrations would be composed to form an elliptical motion.This provided the power for cutting or drilling.The finite element analysis software ANSYS was used to design the structure of the piezoelectric drill.The cutting locus of the drill under the working frequency has been simulated.A prototype was manufactured according to the simulation,the laser scanning experiment on the prototype showed that the working frequency of the drill was 56 kHz,namely the cutting motion could reach to 336×104 times/min and the cutting amplitude could be limited to the micron level.The experiment showed that when the common dental drill was fixed on the prototype,the cutting and drilling can be performed on the common print paper,hardboard,aluminum plate,steel plate and so on.