Servo hydraulic presses are generally driven by a plunger pump to supply oil to the hydraulic cylinder to achieve slider movement. In order to realize the fixed-range and constant-pressure process of the hydraulic press slider, the oil flow in the input cylinder must be precisely controlled.
The basic working principle of the servo-hydraulic press is introduced as follows:
The internal meshing pump driven by two groups of AC servo motors is directly connected to the upper and lower chambers of the master cylinder, and a safety module is connected between the pump and the cylinder. The pump outlet, the safety module, and the upper and lower chambers of the master cylinder are respectively connected with pressure sensors to detect the pressure of the system, and the input control system is used to servo control the speed of the AC servo motor.
When the servo hydraulic press system overpressures, the cartridge valve spool of the safety module opens to release the pressure into the oil tank. The outlet of the pump is equipped with a safety device, which also releases pressure to the tank in case of overpressure.
The control valve group of the servo-hydraulic press adopts proportional servo constant pressure control technology, which is conducive to improving the reaction speed of the filling valve. The pressure sensor is used to detect the pressure, and the input control system is used to control the proportional servo valve for the pressure supplement.