Research On Electro-hydraulic Control System For High Speed Turret Punch Press

Press formation is one of the most advanced sheet metal processing methods in modern manufacture. Rapid NC turret punch press was used as advanced press process equipment. For the time being, the high speed hydraulic control system, as the key component still relies on importation, which is not suit for our economic situation because of shortcoming of high cost.Punch press driver system with electro-hydraulic servo valve employed has good characters of fast respond, high control precision. On the other hand, it has disadvantages of high cost, the huge energy waste and sensitive to oil pollution. High speed on/off solenoid valve is inexpensive, simple in structure and not sensitive to oil pollution compare with servo valve, although it has shortcoming of small flow rate. Cartridge valve use 2 way single directional components as main valve and use pilot control and plug in connection, which has advantages of small leakiness, small flow resistance, fast respond, mass flow rate, easy to control by pilot valve and easy to integrate. These features compensate shortcoming of high speed on/off solenoid valve.The complex 4 way 12 port valves which used in this project take on/off solenoid valve as pilot valve and cartridge valve as main valve, which have priority of low cost, high output speed and simple in circuit.4 functional ports of complex valve were employed in punch press circuit. A new way in field of turret punch press hydraulic control was found by this way and no related report found on this kind of complex valve using in rapid turret punch press to update.The static analysis and two schemes on system are presented first, then the system model is built and simulation is completed by using Simulink tools of Matlab. As a result, system position curve, velocity curve, and pressure curve are gotten.The last part of this article analysis the simulation results and gave explanation for features of every stage in a punch cycle. Then related design and parameter decision roles are given from the key factors which affect the punch speed. At the end, by referencing well used system, improve advices were given for the system.