In our daily lives, we are constantly exposed to bottle caps. There is significance to bottle cap mould in the water bottles, drug containers, and divestment sectors. In order to enjoy the best performance and excellence of bottle cap moulds, it is paramount to know the details of the manufacturing process that enters into the manufacture of different bottle caps.
Shampoo bottle cap mould design
Overview
After our understanding of the bottle cap molds, a customer reached out to Go4Mould to find out how we could help them put together a solution that would ensure the smooth demoulding of the plastic parts, as well as ensure the quality of their products. It was after doing extensive research on their product that this company proposed a solution in hopes that it would be the answer to the problem they faced.
Problem:
To ensure the smooth demoulding of the shampoo bottle caps, it is necessary to design the corresponding arc core pulling mechanism and automatic unthreading mechanism. At the same time, in order to ensure the quality of plastic parts of the bottle cap moulds, certain requirements are also put forward for the casting system of the mold.
Shampoo bottle cap mould design solution:
Bottle cap mould structure design
Design of gating system
Figure 1: Gating system
Considering that the bottle cap requires a smooth surface, the mold is easy to demold, and the overall structure of the mold. Go4mould designed a latent gate, which is selected on the outer cylindrical surface of the bottle cap, as shown in Figure 2.This can not only ensure the surface quality of plastic parts but also facilitate automated production. The diameter at the entrance of the main runner is 3mm, and the demoulding slope is 1.5°; the cross-sectional shape of the cross runner is U, and the radius is 4mm. The diameter of the inlet of the runner is 3.5mm, and the demoulding slope is 1°. The diameter at the entrance of the latent gate is 0.8 mm.
Design of automatic unthreading mechanism
To form the external thread of the bottle cap, an automatic unthreading mechanism is built into the mold. According to the preset hydraulic pressure, the hydraulic motor drives the chain to drive the sprocket, transferring the movement to the gear shaft. As a result of meshing the gear shaft with the teeth of the threaded ring, the bottle cap is automatically unthreaded. When the automatic unthreading process is complete, the mold will perform arc core pulling by facets on both the fixed core and the small core bottom cylinder.
Figure 2: Automatic unthreading mechanism
Design of the arc core-pulling mechanism
The nozzle of the plastic part is an arc structure. In order to realize its forming, an arc core pulling mechanism is designed.
Schematic diagram of the arc core-pulling mechanism
4 Arc core pulling mechanism
As the mold moving die moves, the wedge block attached to the fixed part is separated from the arc side core. The arc push block pulls the arc side through its arc groove. As the moving die moves back, the circular pin on the arc side core pushes the block in the arc. This process makes the arc side core move along the arc guide block, finally opening the mold.
Schematic diagram of the internal structure of the arc core-pulling
How the shampoo bottle cap mould works
Assemble the injection mold for the plastic part of the shampoo bottle cap
1: Completion of automatic demoulding. Hydraulic pressure drives the chain after injection, pressure holding, cooling, and other processes. Gear shafts are threaded by the sprocket connected to them. As the gear teeth engage, the threaded ring retreats, automatically demolding the external thread.
Mould assembly drawing
2: Complete the arc core pulling. After the external thread is demolded, the movable mold part continues to move backwards, under the action of the fixed-distance pulling plate, at this time, the locking block and the arc side core pulling are separated, forming a circular shape.
Arc core pull ready. As the moving die continues to retreat, the arc push block pulls the arc side core through its arc groove, so that the circular pin on the arc side core moves along with it.
As the die moves back, it moves along the guide groove in the arc push block, and finally the arc side core moves along the guide groove in the arc guide block until the positioning screw moves to the lower limit position and the arc completes the core pulling.
3: Complete the demoulding of plastic parts. The moving mold continues to retreat, and the positioning screw moves to the lower limit position to drive the push plate, so that the plastic part and the pouring system condensate are separated from the core, thereby realizing the demoulding of the plastic part.
4: Complete the mold reset. The mold starts the mold clamping process, the threaded core is reset under the action of the chain and the gear shaft, and the push plate is reset by the fixed plate. So far, the mold has completed the complete motion cycle process.
Shampoo bottle cap mould design-Result
Go4mould designed a four-cavity automatic offline mold according to the structural characteristics of shampoo bottle caps and product molding requirements.
In order to ensure the surface quality of plastic parts, a gating system with a balanced layout is designed and a latent gate is used.
In order to realize the formation of the arc part of the bottle cap, designed a circular arc core pulling mechanism.
In order to facilitate the forming of the external thread of the bottle cap, an automatic unthreading mechanism was designed.
In order to realize the smooth demoulding of the product, a push plate pushing mechanism was designed.
After the shampoo bottle cap moulds are produced, it runs smoothly, and the molded plastic parts meet the process requirements. The practice has proved that the injection mold has a reasonable structure and can provide a reference for similar mold designs.
