Three-dimensional (3D) printing is a technology being researched and developed in many different areas such as architectural, medical, aeronautical, as well as in mechanical. With 3D printers, digital models can be fabricated quickly.
The goal of this research was to design a jetting valve system actuated by coil motor. After designing the structural components and describing the principle of operation of the valve system, a reliable and speedy control system was presented to provide consistent quality for printed parts.
In order to verify the practicality of the dispenser, experiments were conducted on the jetting valve system actuated by a coil motor in which the thrust force of coil motor depends on the size of copper wire and current applied. A valve nozzle was designed with a needle head of 1 mm and a nozzle angle 102.8°, and a nozzle diameter was 0.5 mm. Glycerol glue with the viscosity 1200 cP was used as the dispensed fluid. Tests about effects of the working temperature, backpressure, frequency, stroke of coil motor, and the distance between the nozzle and substrate on droplet diameter were conducted through the jetting valve system. The valve system can dispense droplets uniformly and steadily. The maximum frequency value the dispenser can reach is 80 Hz without backpressure and 100 Hz with supporting backpressure with dots diameter around 1 mm by a steel nozzle of 0.5 mm diameter.

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