Working principle of automatic zipper puller
The working principle of the automatic zipper puller is similar to the syringe used for injection. It uses the thrust of the screw (or plunger) to inject the plasticized plastic in the molten state (that is, the viscous flow state) into the closed mold cavity Inside, the process of obtaining the product after the curing and shaping process inside the automatic zipper head machine.
The working principle of the injection molding of the automatic zipper puller is a cyclic process, and each cycle mainly includes: quantitative feeding-melting and plasticizing-pressure injection-mold filling and cooling-mold opening and drawing. After the plastic part is pulled out, the mold is closed again for the next cycle.
The operation items of the automatic zipper puller include three aspects: control keyboard operation, electrical control system operation and hydraulic system operation. Carry out the injection process action, feeding action, injection pressure, injection speed, ejection type selection, temperature monitoring of each section of the barrel, injection pressure and back pressure adjustment, etc.
Generally, the molding process of the screw type automatic zipper head machine is as follows: first, the granular or powdered plastic is added into the barrel, and the plastic is melted by the rotation of the screw and the heating of the outer wall of the barrel.
Then the automatic zipper puller machine closes the mold and moves the injection seat forward, so that the nozzle is close to the gate of the mold, and then pressurized oil is passed into the injection cylinder to push the screw forward, so that the high pressure and faster Speed injects the melt into a closed mold with a lower temperature.
After a certain period of time and pressure holding by the automatic zipper puller machine (also known as pressure holding), and cooling to make it solidify and shape, the mold can be opened and the product can be taken out. The purpose of the automatic zipper puller machine to maintain pressure is to prevent melting in the mold cavity. The backflow of material will replenish the material in the cavity and ensure that the product has a certain density and dimensional tolerance.
The basic requirements of the working steps of the automatic zipper puller injection molding machine are plasticization, injection and molding. Plasticization is the prerequisite for realizing and ensuring the quality of molded products. In order to meet the molding requirements, the automatic zipper puller machine must ensure sufficient pressure and speed during injection molding.
At the same time, due to the high injection pressure of the automatic zipper puller injection molding machine, a correspondingly high pressure is generated in the mold cavity (the average pressure in the mold cavity is generally between 20 and 45 MPa), so there must be a sufficiently large joint Mould force. It can be seen that the injection device and the clamping device are the key components of the injection molding process of the automatic zipper puller machine.