Hydraulic press for forming metal plates

摘要

A hydraulic press has closed loop feedback control on a slide, a slide pad and bolster cylinders. Hydraulic cylinders actuating various components of the press are controlled according to ideal position estimates to produce consistent and precise pressing action. A closed loop control consists of an ideal position/pressure value generator, a position/pressure detector and an arithmetic unit comparing the ideal and actual position/pressure values. Using the ideal and actual comparison result, the arithmetic unit produces a control signal to drive a cylinder to a desired position/pressure. The hydraulic press is capable of performing several operations on a workpiece in one press cycle, an improvement over presses requiring several operation steps or die changes. The bolster cylinders augment clamping force, reduce shock, and improve die alignment to produce better results with less wear on press components.