What is a mold? What is its structure?

A mold is a "model" used to inject resin in a molten state into it. The molds used in injection molding are often compared to the "taiyaki model". Just like making taiyaki, the upper and lower dies are fastened, and the inner cavity of the buckle is filled with material to make the shape of the product. Resin processing is basically made of metal, so it is called a mold. The material of the mold is mostly alloy steel or stainless steel, which is pre-hardened steel. The basic manufacturing method of molds is to engrave and cut metal blocks with NC machines, etc. Depending on the cost strategy or shape, the mold may be divided into multiple parts and processed separately, or the mold after engraving processing may be treated with heat treatment such as quenching.

Molds are basically set of 2 molds. The purpose is to close two molds, fill them with resin material, and then open the mold to remove the molded resin product. The mold that completes the front forming of the part is called the cavity, and the mold that completes the inner molding is called the core. In most cases, the mold is opened horizontally on the left and right, the cavity is fixed, and the core performs the reciprocating motion of opening and closing. Most of the cavity side molding is the surface part of the part, and in order to ensure the aesthetics of the part surface, it is generally not necessary to configure too many parts on the cavity. Sometimes, in order to make the style of the part beautiful, embossing processing is used. ON THE OTHER HAND, ON THE CORE SIDE, THERE ARE USUALLY MANY COMPONENTS SUCH AS EJECTOR PINS THAT ARE USED TO DETACH THE PARTS FROM THE MOLD. Depending on the structure of the mold and the shape of the corresponding resin injection site (gate), there is also a type of three-plate mold that is divided into three parts.