The injection molding machine is divided into plunger injection molding machine and screw injection molding machine according to the plasticization method. According to the transmission mode of the machine, it can be divided into hydraulic type, mechanical type and hydraulic-mechanical (link) type. Automatic, semi-automatic, manual injection molding machine.
(1) Horizontal injection molding machine: This is the most common type. The mold clamping part and the injection part are on the same horizontal center line, and the mold is opened in the horizontal direction. Its features are: short body, easy to operate and maintain; low center of gravity of the machine, relatively stable installation; the product can be automatically dropped by gravity after ejection, easy to achieve fully automatic operation. At present, most injection molding machines on the market use this type.
(2) Vertical injection molding machine: its clamping part and injection part are on the same vertical center line, and the mold is opened in the vertical direction. Therefore, the floor space is small, the inserts are easy to install, and the molds are convenient to load and unload, and the materials falling from the hopper can be uniformly plasticized. However, after the product is ejected, it is not easy to fall automatically. It must be removed by hand, and it is not easy to realize automatic operation. Vertical injection molding machines are suitable for small injection molding machines. Generally, injection molding machines below 60 tons (60 tons refers to clamping force) are used more, and large and medium-sized machines are not suitable.
(3) Angle injection molding machine: its injection direction and the mold interface are on the same side, it is especially suitable for flat products where gate marks are not allowed in the machining center part. It occupies a smaller area than a horizontal injection molding machine, but the insert placed in the mold is easy to fall down. This type of injection molding machine is suitable for small machines.
(4) Multi-mold turntable injection molding machine: It is a special injection molding machine with multi-station operation, which is characterized in that the mold clamping device adopts a turntable structure, and the mold rotates around the rotation axis. This type of injection molding machine makes full use of the plasticizing ability of the injection device, which can shorten the production cycle and improve the production capacity of the machine. Therefore, it is especially suitable for large-volume products with long cooling and setting time or requiring more auxiliary time due to the placement of inserts Production. However, due to the large and complicated clamping system, and the clamping force of the clamping device is often small, this injection molding machine is used more in the production of plastic shoe soles and other products.
General injection molding machines include injection devices, mold clamping devices, hydraulic systems and electrical control systems.
The basic requirements of injection molding are plasticization, injection and molding. Plasticization is a prerequisite for achieving and guaranteeing the quality of molded products. To meet the requirements of molding, injection must ensure sufficient pressure and speed. At the same time, due to the high injection pressure, a high pressure is generated in the mold cavity (the average pressure in the mold cavity is generally between 20 ~ 45MPA), so the mold clamping force must be sufficient.