①The working cycle program of the flat screen flat screen printing machine takes the flat screen platform type monochrome semi-automatic hand surface screen printing machine as an example. One of its working cycles is: feeding → positioning → setting down → lowering to the ink plate, Raise the ink plate → scrape stroke → raise to the ink plate → lower the ink plate → lift the plate → ink return stroke → release positioning → receive.

In the continuous cycle action, as long as the function can be realized, the time occupied by each action should be as short as possible to shorten the period of each work cycle and improve work efficiency.

③ Embossing line. In the printing process, the ink and the screen printing plate are squeezed to the ink plate to form a contact line between the screen printing plate and the substrate, which is called the impression line. This line is at the edge of the squeegee, and countless embossing lines form the printing surface. Realizing the ideal impression line is very difficult, because the printing stroke is a dynamic process.

③Working principle of screen printing machine. Taking the commonly used hand-shaped screen printing machine as an example, the working principle of the screen printing machine can be described as follows: the power is transmitted through the transmission mechanism, so that the squeegee squeezes the ink and the screen printing plate in motion to make the screen The printing plate and the substrate form an impression line. Because the screen has tension N1 and N2, it generates force F2 on the squeegee. The resilience makes the screen printing plate not contact the substrate except the impression line. Under the action of the squeezing force F1 of the squeegee, the printing is leaked from the moving impression line onto the substrate through the mesh.

During the printing process, the screen printing plate and the squeegee move relative to each other, and the squeezing force F1 and the resilience F2 also move accordingly. Under the action of the resilience, the screen returns in time to disengage from the substrate to avoid The blot is dirty. That is, the screen is constantly deformed and rebounded during the printing process.

The squeegee is separated from the substrate together with the screen printing plate after the one-way printing is completed, and at the same time, it returns to the ink to complete a printing cycle. The distance between the upper surface of the substrate and the reverse side of the screen printing plate after the ink is returned is called the same page distance or screen distance, which should generally be 2 to 5 mm. In manual printing, the technique and proficiency of the operator directly affect the formation of the impression line. In practice, screen printing workers have accumulated a lot of valuable experience, which can be summarized into six points, namely, to ensure the linearity, uniform velocity, equiangularity, pressure equalization, centering and vertical edge in the movement of the squeegee.

In other words, when printing, the squeegee should move in a straight line without shaking from side to side; it cannot be slow in the front and fast in the back, slow in the front and slow in the back or abruptly and quickly; the inclination angle to the ink board should remain unchanged, and special attention should be paid to overcome the inclination angle The common problem of gradual increase; the printing pressure should be kept uniform; the distance between the squeegee and the inner sides of the screen frame should be kept equal; the ink plate should be perpendicular to the frame.