Stop mechanism for a bending press, plate shear or the like machines

Claim 1

A stop mechanism for a bending press, plate shearing press or like machine in combination with a work-table and with a work-piece stop which is horizontally adjustable along the work-table thereby defining the position of the work-piece relative to the bending or shearing machine comprising: an adjustable position-preselector serving as a position control-unit coupled with said work-piece stop to determine the momentary difference between the actual position and the value set by the preselector; an indicator of the momentary position of the workpiece stop which is mounted on said position control-unit; programming means for programming said position control-unit in a desired position; a hydraulic piston-cylinder unit having hydraulic drive means; said piston-cylinder unit having one cylinder with a chamber on each side of said piston which can be displaced in two opposite directions, the displacement of said piston in one of said directions displacing said stop in that direction and the displacement of said piston in the other direction displacing said stop in the other direction; said hydraulic drive means comprising a pump and separate pipes from said pump to each of the chambers on each side of the piston so that the driving of said pump is controlled by said position control unit coupled with said work-piece stop under a slight over pressure of the hydraulic fluid.