螺旋线形阀压电泵的理论与试验研究*

有阀压电泵在精细化工、MEMS、生物医学工程等领域具有重大应用前景。为了克服有阀压电泵结构复杂、跟从与截止性差、成本高等缺点，设计一种异形拟悬臂梁结构的螺旋线形弹性固支阀，其螺旋臂长是简单悬臂梁阀的数倍，工作时开启度大，且因其螺旋线形弹性结构，阀体不仅可以上下回位，左右也具有对中功能，并把这种阀安装在有阀压电泵的泵腔内形成螺旋线形阀压电泵。在深入分析有阀压电泵优缺点的基础上分析螺旋线形阀压电泵的工作原理，依照泵内部能量传递的路径建立压电驱动(电压、频率)为输入与泵流动(流量、压差)为输出之间的关系式，加工试验样机，并进行性能测试试验，螺旋线形阀压电泵具有泵功能，证明了其有效性和理论分析的正确性。试验结果表明：随着驱动电压的增大，泵的输出流量和压差呈上升趋势，这个结果与Matlab数值仿真计算结果趋势一致。在电压为220 V、频率为30 Hz时，得到仿真流量41.26 mL/min，实际试验流量为10.2 mL/min，误差75.3%;在电压为220 V、频率为20 Hz时，得到仿真流量27.51 mL/min，实际试验流量为22.8 mL/min，误差17.2%。

Theoretical and Experimental Research on the Piezoelectric Pump with Helical Linear Shaped Valve

The piezoelectric pump with valve can potentially be applied in many fields such as fine chemicals, MEMS and the biomedical engineering, etc. In order to overcome the shortcomings like complicated structure, low following up, poor cutoff and high cost of valve piezoelectric pump, a new type of valve with elastic fastened helical linear support that has special-shaped cantilever beam structure is designed. The length of spiral arm of the new design is several times longer than the simple cantilever valve. The opening size is bigger than the pump with traditional valve in operation. In addition, because of the helical linear elastic structure, the valve body can not only be returned from both up and down but also be centered from both left and right. It can be installed in the pump cavity piezoelectric pump with valve. The operating principal of the piezoelectric pump with valve of helical linear shape is developed based on extensive analysis of its advantages and shortcomings. The relationship between piezoelectric driving (voltage, frequency) and the pump flow (flow rate, pressure difference) is established considering the energy delivering route in the pump. Finally the sample machine is built with performance testing carried out. The testing results of pump function for the piezoelectric pump with valve of helical linear shape is consistent with theoretical analysis. The testing result shows that as the driving voltage increases, the output flow and the differential pressure tend to rise. The results are in agreement with the trend of numerical simulation calculation in Matlab. At 220 V voltage 30 Hz, the simulation flow is 41.26 mL/min while and the field testing flow is 10.2 mL/min. The deviation is 75.3%. At 220 V voltage 20 Hz, the simulation flow is 27.51 mL/min while the field testing flow is 22.8 mL/min. The deviation is 17.2%.