Summary of die technology for automobile headlamp decorative frame (main bezel)

The decorative frame of automobile headlamp is one of the most important parts on the lamp. The appearance requirements are strict, and the mold needs electroplating treatment. For the mold of automobile headlamp decorative frame, the following points should be paid attention to in the design:

(1) For electroplated parts, it is first necessary to avoid fusion wiring, because any fusion wiring of electroplated parts will appear, which will affect the appearance of plastic parts. When designing the gating system, it is necessary to avoid fusion wiring. If fusion wiring is inevitable, try to drive it to the non appearance area. Before designing the gating system, it shall be verified through mold flow analysis.

(2) The surface of the decorative frame is generally designed with patterns. When designing the mold, pay attention to the depth of the patterns of the plastic parts, which is generally easy to produce flow patterns.

(3) The molding process range of plastic parts is small, bright spots are easy to occur on the surface of plastic parts, and it is difficult to control. When designing the mold gating system, the runner should be thick and large. The gate adopts fan-shaped gate. The maximum gate width is about 35 ~ 40mm, which is conducive to melt filling.

(4) The plastic parts of the decorative frame are easy to stick to the fixed mold. The preliminary design precautions to solve the problem are generally as follows:

a. The reverse buckle pattern is designed on the inner side of the plastic part which is easy to stick to the mold and has large wrapping force. The depth of the reverse buckle pattern is 0.5 ~ 1mm, and the reverse buckle pattern is designed near the fillet of the plastic part.

b. Where the fixed mold wrapping force of the plastic part is large, the corresponding inner side of the plastic part is designed with stiffeners, and the reverse buckle hook is designed on the push rod. According to the characteristics of this plastic part, stiffeners and boss columns (commonly known as cylinder columns) shall be designed on the side plastic parts in the six LED lamp areas to avoid deformation of the plastic parts.