On-demand micro liquid drop generation method based on pneumatic and electrohydrodynamic hybrid driving

Abstract

The invention discloses an on-demand micro liquid drop generation method based on pneumatic and electrohydrodynamic hybrid driving. The device for realizing the method is supplied by a high-pressure gas source, a pressure regulating valve is used for controlling the air pressure at the front end of a high-speed electromagnetic valve, and a single-chip microcomputer controls the opening time of thehigh-speed electromagnetic valve. After the high-pressure gas enters a liquid storage cavity, helmholtz oscillation is generated, and the high-pressure gas is stable after being attenuated by severalperiods. An industrial camera and an LED lamp are used for monitoring the production process of the micro liquid drops and adjusting the system in an auxiliary mode. The high-speed electromagnetic valve and the pressure regulating valve are reasonably adjusted according to the air pressure waveform detected by an air pressure sensor. The air pressure waveform is controlled by adjusting the high-speed electromagnetic valve and the pressure regulating valve, the volume and shape of the micro liquids extruded from a nozzle can be adjusted, so that the size of the micro liquid drops is regulated.Compared with a high-voltage pulse power supply micro liquid drop generating device, the cost is greatly reduced.

Description

technical field [0001] The invention relates to a micro-droplet generation device driven by a mixture of pneumatic and electrohydrodynamics, and realizes the control technology of generating micro-droplets on demand and adjusting its size by adjusting the opening time, air pressure and voltage level of the electromagnetic valve in the device , mainly used in the application of micro-liquid samples, and can be used in printing electronics, drug development, biomedical material printing and other fields. Background technique [0002] As conventional inkjet printing technologies, including piezo-actuated jetting and thermal bubble-actuated jetting, have expanded to other reference areas, more unconventional inkjet printing technologies have also made great progress. These unconventional injection methods mainly include pneumatically driven injection, electrohydrodynamic (EHD) injection, etc. They are used in a wide range of fields including biomedical printing. Among them, th...

AI Technical Summary

Problems solved by technology

However, EHD micro-droplet ejection technology also needs to face many difficulties

Since the liquid generation is affected by the continuous electric field force and the flow rate of the liquid supply system, although the frequency of droplet generation is controlled by voltage, it is difficult to maintain stability, and it is impossible to achieve on-demand injection

Using a high-voltage pulse power supply can overcome the above-mentioned problem of unstable injection frequency to a certain extent, but on-demand injection is still difficult to achieve

At the same time, the price of high-voltage pulse power supply is much higher than that of high-voltage constant voltage power supply, which greatly increases the system cost

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