Share The Design Summary Of Auto Lamp Cover Plastic Injection Moulds

The decorative frame of the car headlight is one of the important parts of the car light. The appearance requirements are strict, and the mold needs to be electroplated. For the automotive headlight decorative frame mold, the following points should be paid attention to when designing:

(1) Electroplating parts should first avoid weld lines because any weld lines on electroplated parts will appear and affect the appearance of plastic parts. Weld lines should be avoided when designing the pouring system. If weld lines are inevitable, try to drive them out In the non-appearance area, the mold flow analysis must be verified before the gating system is designed.

(2) The surface of the decorative frame is generally designed with patterns. When designing the mold, attention should be paid to the depth of the pattern on the plastic part, which is generally prone to flow marks.

(3) The molding process range of the plastic part material is small, and the surface of the plastic part is easy to produce bright spots and is difficult to control. When designing the mold gating system, the flow channel should be thick and large, and the gate should be a fan gate, with a gate width of about 35~40mm, which is conducive to melt filling.

(4) Auto bumper plastic injection moulds are prone to sticking molds. The early design prevention of plastic parts sticking molds is generally:

a. Design undercuts on the inner side of the plastic parts that are easy to stick to the mold and have a large tightening force. The depth of the undercuts is 0.5~1mm, and the undercuts are designed near the rounded corners of the plastic parts.

b. Design reinforcing ribs on the inner side of the corresponding plastic part where the fixed mold wrapping force of the plastic part is large, and design an undercut hook on the push rod. According to the characteristics of this plastic part, reinforcement ribs and boss columns (commonly known as boss columns) should be designed on the plastic parts inside the 6 LED lamp areas to avoid deformation of the plastic parts.

In this mold design, the area with a high gripping force of the plastic part is more than 5 degrees, and a 0.5mm deep undercut pattern is designed on the side of the movable mold, so the ejection and de-molding of the mold are smooth, and the movement of each mechanism is smooth. The mold is safe, stable, and reliable, and the mold does not have the phenomenon of sticking to the mold, successfully solving the problem of such plastic parts sticking to the mold. After the mold trial production of this model, the loading effect is good and the size is stable. The remodeled car lights have been recognized and praised by customers in the auto show, and have created certain economic benefits for customers.

Auto lamp cover plastic injection moluds technology summary

For auto lamp cover plastic injection moulds, the main design points are:

(1) Special injection molding process equipment is required, and an injection molding machine dedicated to the production of BMC plastics is required. The requirements for injection molding process equipment are very strict.

(2) The BMC material is an extra-hard plastic. In mold design, it is necessary to design a heating system and a parting surface design discharge system. The molded parts must be quenched to improve wear resistance and mold life.

(3) The reflector plastic part is a device to prevent direct light on the car lights, reflect the light, and avoid direct light, and the light distribution requirements are strict. Plastic parts are important exterior parts of automobiles, and there are many patterns on the surface of plastic parts for decorative purposes.

(4) The ejection system of the mold design for BMC materials should be balanced, and the specifications of the push rods should be designed as large as possible, and the number should be as large as possible, otherwise it will cause difficulty in molding the plastic parts.

(5) Since the demoulding slope of the high-gloss plating part is too small, it will cause difficulty in de-molding, so the side wall of the mirror plastic part should be designed as large as possible, and it is generally recommended to be 5°~10°. Of course, the premise is that the function and shape of the plastic parts cannot be affected.

(6) Plastic parts cannot have sharp corners and sharp edges, and all corners need to be designed as rounded corners because the formed parts of the mold are prone to stress cracking after quenching.

(7) Note that the lamp head hole of the left and right reflectors and the pattern on the surface of the plastic part are shifted left and right, and cannot be designed to be mirror-symmetrical, because the bulb and the lamp holder will not be separated from the left and right, and the rest of the features are mirror-symmetrical.