Automobile headlights are mainly used for lighting, which can be said to be eyes of car. Headlights are a general term for all automotive lighting systems. Appearance requirements of automotive headlights are high. Several important parts are transparent parts, electroplated parts, etc. It can be said that parts with the highest requirements for appearance of car are headlights, so requirements for mold design and manufacturing are extremely high.

 

Generally, main lighting parts of a car are the front and rear headlights. Different car series have different configurations of headlights, same car series also has different configurations based on high and low configurations. Main parts that make up front and rear lights of a car are: left and right lenses, left and right decorative frames, left and right lamp shells, left and right reflectors, etc. Appearance requirements of automotive headlights are extremely strict.

 

Headlight distribution

 

Headlight construction

 

Headlight product display

 

MOLDFLOW analysis

 

Car headlight lens mold structure case
Car headlight lens (also known as light distribution mirror) is the outermost transparent part of car headlight. Generally, headlights of a car are white and transparent, rear combination lights are red (or multi-color) and transparent. Surface of automobile headlight lens plastic part is a Class A curved surface (i.e. gap between adjacent curved surfaces is between 0.001 and 0.005 mm, curvature change is less than 0.005 degrees, and shear rate change is less than 0.16 degrees.), with a super-hard coating on the outer surface. Transparency requirements of inner and outer surfaces are extremely high, and it is the most important automotive exterior part.

 

 

Temperature control system on fixed mold side of mold consists of 4 cooling water channels, 4 in and 4 out. Temperature control system on movable mold side consists of 5 cooling water channels, 5 in and 5 out, as shown in figure below. In order to reduce molding cycle and improve quality of plastic parts, distance from each branch water pipe to cavity surface and length of each branch water pipe must be roughly equal, so that temperature at each part of mold cavity can be roughly balanced.
For this reason, cooling water channel adopts a combination of "vertical water pipe + inclined water pipe + spacer water well". This cooling system first uses vertical water pipes, followed by inclined water pipes, and only uses spacer water wells as a last resort. This combination of cooling water channels is evenly arranged and close to cavity, which is suitable for injection molds with large batches and high precision of molded plastic parts. Its disadvantage is that processing of cooling water pipes is more troublesome.

 

Analysis of product requirements for light distribution mirror
Light distribution mirror represents appearance of the entire front and rear lights, and appearance requirements are much higher than lamp body. Therefore, light distribution mirror must be beautiful, without silver light, welding marks, and shrinkage. If there are defects that cannot be avoided due to injection molding or mold structure, defects must be minimized or driven to non-important parts of light distribution mirror.

 

Hot-scaling ribs
Hot-scaling ribs are used to seal with rear lamp body! It uses thermal friction method to contact cloth glue groove of lamp body. Its thickness and shape must be paid attention to. If thickness is too large or too small or shape does not meet requirements, it may lead to poor sealing during assembly process with lamp body!

 

Supersonic ribs, hot-scaling screw holes
Supersonic ribs and hot-scaling screw holes are used to assemble light distribution mirror and lamp body, and play a role in tightening! It has very strict requirements on size.

 

As name suggests, light distribution mirror is decorated inside lamp body, directly decorated on decorative ring, and is used to adjust light quality of individual bulbs! Its coordination with decorative ring mainly depends on buckles!