The injection molding machine (vertical injection molding machine) can be decomposed into several stages such as mold clamping, injection/holding, feeding, cooling, mold opening, ejection, etc. from the standard actions. Each stage needs to provide different and appropriate pressure and flow For the oil pump motor, the molding process of the injection molding machine is a changing load state. In the hydraulic system of the fixed pump, the motor continuously provides a constant flow rate at a constant speed. Although the proportional pressure and flow proportional valve (EFBG) can achieve the results of the required pressure and flow rate configuration at each stage, the hydraulic pressure outside the control is required. The oil must still be drained back to the tank. For the injection molding machine, the power consumption caused by the output power consumption is continuous, that is to say, if the injection molding machine is in the standby state, the quantitative pump still continuously provides a constant flow rate and directly discharges it back to the tank, forming a considerable and unnecessary power Costly.
The control technology of the servo system can improve the above-mentioned shortcomings of the quantitative pump hydraulic system. The servo motor transmits the signal to the drive through the encoder for precise rotation control, so that the flow demand of the controlled hydraulic oil is directly output through the oil pump, that is to say, the size of the output flow is obtained by the increase and decrease control of the precise speed. In terms of hydraulic oil pressure control, the pressure signal is connected in series to the oil pump, and the pressure signal result is fed back to the drive end for continuous closed-loop control to achieve the purpose of precise pressure control. In this way, the servo control system can accurately provide The pressure and flow required in each stage of injection molding, compared with the fixed pump system, can greatly reduce the power consumption of the output.