针对超声换能器设计上存在的双共振峰或多共振峰等常见问题,提出了一种基于频率灵敏度方法的换能器结构优化设计方法。以芯片键合超声换能器为例,采用模态频率灵敏度的方法,通过最小量地修正变幅杆的直径,实现轴向工作频率与其他非工作频率的分离,有效地抑制了工作频率附近杂散的非工作模态对自身模态的干扰,确保在工作状态下换能器被驱动在单一的工作频率,从而提高了超声能量输出的稳定性。
To the common problems that double resonant peaks or multiple resonant peaks in ultrasonic transducer,a structure optimization method based on frequency sensitivity was introduced in this paper.For an ultrasonic transducer with double peaks used in wire bonding,the modal frequency sensitivity was investigated to control the double peak problems by modifying the minimal diameter of the horn,which can control effectively the disturb from the non-working modal vibration and the transducer can be driven at the resonant frequency,further the stable outputs of the ultrasonic energy will be improved.