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The electro hydraulics servo tape leaf spring mill is  a special equipment used to manufacture automobile  tape leaf spring. The structure of main body of mill  is  adopted four-column type. The roll gap of mill is  driven by the servo hydraulics cylinder. The type of  two degree computer control system, composed by  microcomputer and PLC, has been adopted in this mill. The movement control requirement of the mill for  manufacturing tape leaf spring has been analyzed The  structure characteristic and forming principle of the  electro hydraulics servo control system of the mill  has  been introduced. The control programs for rolling  leaf  spring and digital PID had been designed for having  accomplished the automatic control of roll gap for  tape  leaf spring and precision indemnity. The precision  and  efficiency requirement of all type of leaf spring at  home and abroad to the mil has been satisfied.
Development of Control System of Electro Hydraulics Servo Leaf Spring Mill