Basic structure of injection mold

<p>The structure of the <a href="https://www.tozhiyuan2.com/plastic-molding" rel="noopener noreferrer" target="_blank">plastic injection molding</a> is determined by factors such as the form of the injection machine and the complexity of the part. Regardless of its complexity, all plastic injection molding can be divided into two parts: a movable mold and a fixed mold. The fixed mold is installed on the fixed template of the injection machine, and the movable mold is installed on the movable template of the injection machine. The moving and fixed molds close the molding cavity and pouring system during injection, and the moving and fixed molds are separated when the mold is opened, and the plastic parts are taken out.</p><p><br></p><p>According to the role played by each part on the mold, it can be subdivided into the following parts:</p><p>(1) Molded parts</p><p>Molded parts are parts that make up the cavity in the designated and movable mold part. It is usually composed of punch (or core), die, insert, etc.</p><p><br></p><p>(2) Pouring system</p><p>The pouring system is the channel through which the molten plastic flows from the nozzle of the injection molding machine into the mold cavity. It consists of a main runner, a runner, a gate and a cold material cavity.</p><p><br></p><p>(3) Guiding mechanism</p><p>The guide mechanism is divided into two types: the guide mechanism between the movable mold and the fixed mold and the guide mechanism of the ejection mechanism. The former is to ensure that the movable mold and the fixed mold are accurately aligned when the mold is closed to ensure the accuracy of the shape and size of the plastic part.</p><p><br></p><p>(4) Demoulding mechanism</p><p>The device used to eject the plastic part from the mold when the mold is opened, also known as the ejection mechanism. There are many structural forms, such as ejector ejection mechanism, push plate ejection mechanism and push tube ejection mechanism.</p><p><br></p><p>(5) Lateral parting and core pulling mechanism</p><p>When there are concave-convex-shaped holes or bosses on the side of the plastic part, a lateral convex mold or core is needed for molding. Before the mold is opened and the plastic part is pushed out, the lateral punch or the lateral core must be pulled out or withdrawn from the plastic part, so that the plastic part can be demolded smoothly. The mechanism that moves the lateral punch or the lateral core is called the lateral core pulling mechanism.</p><p><br></p><p>(6) Heating and cooling system</p><p>In order to meet the temperature requirements of the injection molding process, the mold temperature must be controlled. Therefore, the mold is often equipped with a cooling system and heating elements are installed inside or around the mold. The cooling system generally opens a cooling channel on the mold.</p><p><br></p><p>(7) Exhaust system</p><p>In the injection molding process, in order to exhaust the air in the cavity, it is often necessary to set up an exhaust system, usually by setting up a number of grooves on the parting surface, or using the push rod of the mold or the core and the template. Exhaust through the matching gap between. The exhaust volume of small plastic parts is not large, so the parting surface can be directly used for exhausting, and there is no need to set up an exhaust groove.</p><p><br></p><p>( Other parts</p><p>&nbsp;For example, it is used to fix and support molded parts or parts that play a role of positioning and limiting.</p>