微小型静电泵的设计(2)

Design of micro and small electrostatic pumps(2)

推导出作用于激励膜片上的静电抽压力与微型静电泵极板间所加电场强度、电压及泵的半径、上腔高度的关系公式,并绘制出相应图、表以便选用。因为泵的静电抽压力与上腔高度有关,因此针对膜鼓起时,膜与泵顶距离增加导致静电抽力存在偏差,对静电抽力进行了修正,提出了有效上腔高度的概念,把膜鼓起后增加的体积迭加到基础上腔体积上,然后把它看成是一个以泵底面,有效上腔高度为高的整体圆柱体,再来近似计算圆柱体极板间静电抽压力,并举例介绍了修正计算过程。

A formula is derived out to show the relationship between the electrostatic pressure acting on the excitation membrane with the electric field intensity or voltage between two polar plates of pump, the radius of pump, or the height of upper chamber. Then the corresponding graphs and data tables are presented fbr application selection. With the membrane bulging up, the distance between the top of pump and the excitation membrane increases, which leads to the electrostatic pumping pressure reduced greatly because the electrostatic pumping pressure is related with the height of upper chamber. So electrostatic pumping pressure needs correcting properly and then a concept of effective height of the upper chamber is put forward. The increased volume due to the membrane bulging down is added to the basic upper chamber volume, and the sum is treated as a cylinder with the bottom of pump as bottom and the effective height as the high. Then the electrostatic pumping pressure between polar plates of the circular is calculated approximately. Correction calculation process is introduced with examples too.