Car lights are indispensable important safety protection devices and decorative parts in automobiles. Because it works in high-temperature environment and has the function of reflection and concentration, it needs to be injection molded with thermosetting plastics with almost zero shrinkage, heat resistance, flame retardancy and strong creep resistance.
1. Structural requirements of plastic parts for injection mold design:
The appearance requirements of automotive lamps are extremely high, and no material marks and gate marks are allowed on the appearance, let alone defects such as sink marks, weld marks and flash edges.
he shape of the plastic parts is complex, and the surface requires a high degree of finish. The plastic parts have no inner and outer buckles, and there is no need to laterally pull the core. The plastic parts are left and right mirrored parts.
This product is an electroplated part, with aluminum plating on the appearance, and has strict light distribution requirements. The draft angle design of the outer surface should be reasonable.
In addition, the material of the car headlight is BMC, which is a thermosetting plastic. This material is a special hard material with almost zero shrinkage, which does not need to be added in the injection mold design. Since BMC is a special hard plastic, it has high dimensional accuracy and good processing performance, but poor fluidity.
2. The structure of injection mold tooling
The car headlights are left and right mirrored parts, so the number of cavities is selected as 1+1, and a cold runner gating system is adopted. Moreover, the inner and outer sides of the plastic part are not buckled, so there is no need to provide a lateral core pulling mechanism.
3. Molding process of injection mold tooling
The BMC material is added to the barrel of the injection molding machine, and shear heat is generated by the rotation of the screw to melt it at a lower temperature, and then the thick gelatinous material is injected into the preheated injection mold tooling under high pressure. Under the action of high temperature, a chemical reaction is carried out, and it is cured and formed after being kept under pressure, and the molded plastic part is obtained by opening the mold and taking it out.
The above content introduces the injection mold design and manufacturing analysis of automobile headlights in detail. If you want to know more about it, you can pay attention to Zhongde. As one of the best injection molding manufacturers in China, our company provides high-quality, low-cost plastic and rubber injection molding parts to global customers.
Zhongde’s scientific injection molding process helps you reduce design risks, with the support of many senior project managers and engineering experts, communicate in all project stages from design to production, and cut the costs to the bone, if you need injection molding services, welcome to consult Zhongde.
