Hydraulic servopress works without valves: Valveless hydraulic drive converts standard press into servopress

摘要

A hydraulic drive without conventional control valves? That's how the PSH press drive is described by officials at Voith Turbo H+L Hydraulic, Rutesheim, Germany. Instead of using conventional servo or proportional valves to control flow and pressure in a hydraulic press drive, the PSH drive controls the rotational speed and torque of an electric servomotor that drives a hydraulic pump. Providing closed-loop control of motor speed and torque, in turn, controls flow rate and pressure of the press's hydraulic system.