提出了利用正弦波信号驱动压电双晶片振子,应用惯性冲击力实现机构微小位移的技术方案,建立了机构运动的数学模型。设计了斜面结构,使正弦波作用产生的周期性惯性冲击力形成竖直作用于微位移驱动机构的分量,通过改变正压力调整摩擦阻力的大小,并推导了Qu〈QD〈Fx的微位移机构运动条件。对微位移机构的速度-频率、速度-电压和位移特性进行了试验,结果表明:变摩擦式微位移机构样机能实现较稳定的正向运动,电压一定且频率为30~38Hz时,运动速度随频率的增加而稳定增加;频率一定时,运动速度随电压增加而稳定增加;在35Hz、90V的正弦波激励下,样机平均步长达到2μm,速度达到1mm/s。
By using sine wave to drive the piezoelectric cantilever bimorphs, the micro-displacement of a mechanism was realized by the inertial impact force drived. A mathematical model for the mechanism movement was established and a mechanism with bevel was designed to make the periodical inertial force produce a vertical force onto the micro-displacement mechanism to adjust the friction by changing vertical pressure. The moving condition Qu〈QD〈Fx was deduced. The velocity characteristics under different frequencies and voltages were tested. The results show that micro-displacement mechanism realizes stable and forward direction movement. When the voltage is fixed and the frequency is 30-38 Hz, its velocity increases with the frequency increases. When the frequency is fixed, its velocity increases with the voltage increase. The average step is up to 2 μm and the velocity is up to 1 mm/s when the mechanism is actuated by the 35 Hz and 90 V sine wave.