The development trend of automotive molds is to replace metal bumpers with plastic bumpers. Currently, the design of plastic bumper molds in China mainly adopts two structures

1. External fractal

2. Internal fractal

The first structure is relatively simple compared to mold design, while the second structure is much more complex compared to mold structure, mold strength, etc.

But due to the increasing demand from consumers for the appearance of cars, the internal fractal structure, which was originally only used for high-end car bumpers, has gradually replaced the first structure. Due to the confidentiality of the company, I will briefly discuss the internal fractal:

Due to the setting of the parting line on the B-side, if a conventional inclined plane is used for pushing, the pushing mechanism will interfere with the inclined pushing block at the fixed mold barb after mold opening, causing mold damage. Therefore, avoiding the collision between the inclined roof and the fixed mold has become a key design point

Generally, the following points are used to solve the problem

1. During mold opening, the inclined top block is synchronously pushed out, which means using hydraulic pressure to push the push plate (also known as a nitrogen spring) to maintain the relative position between the push plate and the fixed mold.

2. Utilizing the deformability of the product, pull the end of the part inward through the horizontal slider inside the inclined top block, and control the stroke through the guide rail at the end of the horizontal slider to make the end of the part detach from the fixed mold barb

3. Open the mold to separate the product from the fixed mold.

4. Continue to eject and control the lateral sliding outward movement through the guide rail at the end of the lateral slider to deform and reset the product

5. Finally, continue pushing upwards until the product is removed