Due to the common plastic machinery, and the control of relatively simple machine is mostly by single operation, mechanical reliability level of control system, the plastic machinery and the reliability of the requirements of the development of embedded products using so dedicated controller can satisfy user's requirements, the overwhelming majority of great price, and widely used in industry, especially in the injection molding machine is widely applied in moulding equipment, application of higher proportion. In extrusion equipment, due to the high reliability PLC, short development cycle and application of PLC application mature, the dominant position. Currently in use of industry, Omron PLC Siemens brand, Mitsubishi, NAIS, LG, etc. Siemens provides a series of plastic machinery based on PLC controller.
Along with the development of technology of plastic machinery, the controller is not simple action control, but including melt temperature, injection pressure, velocity and pressure of time, cooling process and hydraulic windings of comprehensive control. Most USES open-loop control, and is currently developing direction to the closed-loop control. The new equipment for the controller and response speed control ability has further requirements, the traditional based on embedded products to meet the demands of the controller, thus in the new equipment and large equipment with PLC. This PLC in high-end and large equipment used, special controller in the use of low-end equipment in the next three years in plastic machinery industry will not change. Competitive price is into the largest number of general plastics machinery controller. Market,
Plastic machinery manufacturing process characteristics with great potential energy, for example, injection molding machines are generally classified into process of clamping, rubber, plastic, pressure, cooling, mould etc. Several stages, stages need different pressure and flow. For oil pump motor, injection molding process is a change in the load, the hydraulic system of quantitative pumps, pump motor with constant speed unsteady flow, provide extra hydraulic oil through the relief valve, this process is called pressure backflow, this will cause throttle backflow of energy losses. The inverter used to solve this problem, by adjusting the rotational speed pump, oil pump in different stages of the production of injection pressure, provide appropriate to the greatest extent of reducing energy loss.