Design And Manufacture Of Burrowing Sand Piezoelectric Micropump

Piezoelectric pump is simple in structure,small in size and easy to be miniaturized.It has been applied in many fields such as biomedicine,chemical engineering,robot and so on.At present,there is little research on the transmission of solid-liquid slurry by piezoelectric pump,especially for the slurry with large solid particles and high concentration.In this paper,we investigated the sediment drilling organisms in nature,mainly studied the behavior of shellfish in sand drilling,and designed and manufactured piezoelectric pump which can drill in sediment environment.This paper attempts to design two kinds of special-shaped pipe structure,a valveless piezoelectric pump with expansion/contraction pipe structure,and piezoelectric pumps with cantilever valve structure and integral open valve structure.It is verified that the designed piezoelectric pump with integral open valve has better sand drilling ability.The piezoelectric vibrator used in this paper is mainly circular bimorph piezoelectric vibrator with simple structure.The metal substrate material is nickel alloy with diameter of Φ20 mm and thickness of0.25 mm.The diameter of ceramic plate is Φ17 mm and the thickness is 0.2 mm.The experimental results show that when the depth of the pump cavity is 0.7 mm,the inner diameter of the inlet and outlet pipe is Φ3.5 mm,under the driving of ±100 V square wave voltage and the frequency of 150 Hz,the pure water flow rate is as high as 168ml/min.at this time,the sand drilling speed is the fastest,the depth of sediment drilling is 63 mm,and the average drilling speed is 0.525 mm/s.The main research contents of this paper are as follows: the characteristics of piezoelectric vibrator are analyzed,including the influence of piezoelectric material,structure of piezoelectric vibrator,support mode of piezoelectric vibrator on the output displacement and output pressure of piezoelectric vibrator,and the relationship between the amplitude of piezoelectric vibrator and driving voltage,waveform,frequency,with or without load is tested by experiment;the design principle of single cavity valve piezoelectric pump is discussed.On the basis of the theory,the working principle and working mode of the piezoelectric pump are analyzed,the properties of the slurry in the actual sediment environment are analyzed,and the structure of the piezoelectric pump which may realize the sand drilling function is designed.The manufacturing process of the double chamber parallel piezoelectric pump is introduced.The pump body adopts3 D printing technology,and different valve structure uses different processing technology.Three kinds of waterproof treatment of the piezoelectric pump are analyzed and compared.The effects of input voltage,voltage waveform,pump chamber height and inlet and outlet pipe diameter on the pure water flow rate of the piezoelectric pump are measured and analyzed,and the variation of sediment depth with time under different frequencies is measured.