Valveless piezoelectric micro pump

Abstract

The invention discloses a valveless piezoelectric micro pump comprising a vibrating plate, a pump body (8) and an upper cover plate (1) connected on the pump body (8) through a bolt (6); a cavity is formed between the upper cover plate (1) and the pump body (8); a vibrating plate is arranged between the upper cover plate (1) and the pump body (8); the cavity is divided into a liquid inlet negative pressure cavity and a liquid outlet negative pressure cavity by the vibrating plate; a vibrating diaphragm (2) and an annular piezoelectric ceramic chip (3) are coaxially adhered to form the vibrating plate; cone holes are distributed on the middle circular area and the peripheral annular area where the annular piezoelectric ceramic chip (3), the upper cover plate(1) and the pump body (8) do not contact with in the vibrating diaphragm (2); the bigger ends of the cone holes face towards the liquid inlet negative cavity; and the smaller ends of the cone holes face towards the liquid outlet negative pressure cavity. The valveless piezoelectric micro pump is simple in structure, light in weight, big in power capacity, easy to assemble for whole machine manufacturing and low in production cost.

Description

technical field [0001] The invention relates to a microfluid mechanical device utilizing the inverse piezoelectric effect of a piezoelectric ceramic material, in particular to a valveless piezoelectric micropump. Background technique [0002] Piezoelectric micropump is an important direction in the field of MEMS research. As the driving source of microfluidic system, it is an important symbol of the development level of microfluidic system. Piezoelectric micropumps have been widely used in micro-delivery of drugs, bioengineering, microchemical analysis, printer inkjet arrays, micro-volume liquid or gas distribution, fuel micro-injection, molecular recognition, cell separation, disease diagnosis, drug screening, environmental monitoring, integration Cooling of electronic components, lubrication of micro-components, propulsion of micro-satellites and other scientific and technological fields. [0003] According to whether the piezoelectric micropump has a valve or not, it can...

AI Technical Summary

Problems solved by technology

[0003] According to whether the piezoelectric micropump has a valve or not, it can be divided into a valved micropump and a valveless micropump. Although the working principle of the valved micropump is relatively simple, easy to control, and the manufacturing process is relatively mature, the whole pump There are mechanical movable parts such as valves in the body. Due to the constraints of processing technology and machining accuracy, there are still some problems in the actual production and application of micropumps with valves: frequent switching of the valves is easy to fatigue and damage, resulting in low reliability of the micropump. , short service life; easy to block some liquids; the silicon film of the micropump is fragile, and the yield is low; the production of the whole machine is difficult and the processing cost is high

[0004] In order to overcome the deficiencies of the valved micropump above, the patent document with the publication number CN201246300 discloses a "V" tube valveless piezoelectric pump. The valveless piezoelectric pump is installed on the inlet pipe and outlet pipe of the pump body respectively The V-shaped tube and the inverted V-shaped tube realize the one-way flow control of the liquid medium, simplify the structure of the valveless piezoelectric pump, and improve the reliability of the micro piezoelectric pump, but the valveless piezoelectric pump also has some problems. Disadvantages: The V-shaped tube of the valveless piezoelectric pump is difficult to manufacture and install, and the production cost is high; the average area ratio of the inlet and outlet tubes per unit area is small, and the flow adjustment range is small

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