Design principle of ejection mechanism of injection mold


1. The movement direction of the ejection mechanism sho […]

1. The movement direction of the ejection mechanism should be accurate and reliable; there should be no jamming during the movement. It must have sufficient strength and rigidity to withstand the role of demolding resistance.
2. It is necessary to ensure that the plastic parts do not deform during the launch process, which is the basic requirement for the ejection mechanism. During the design, the release force should be distributed as close to the core as possible, and the effective area should be as large as possible to prevent the plastic parts from being deformed or damaged. Generally, the demolding resistance can be applied to places that are not easily deformed such as reinforcing ribs, flanges, and thick walls. When considering the demolding force, the size and distribution of the adhesion force of the plastic part to the injection mold, as well as the shape and surface roughness of the plastic part must be considered.
3.In general, the design of the injection mold should ensure that the plastic part remains on the side of the movable mold after opening the mold, because this can simplify the ejection mechanism.
4. If the ejection part needs to be set on the use or assembly reference surface of the plastic part, in order not to affect the size and use of the plastic part, the contact part of the push rod and the plastic part should generally be recessed a little. And the end face of the push rod should be higher than the reference surface, otherwise the surface of the plastic part will be raised, affecting the flatness and appearance of the reference surface.