Abstract: A metal sheet processing apparatus for replacing dies with one another and for positioning a plate material in longitudinal directions. The metal sheet processing apparatus includes left and right side frames (3L, 3R), upper (5) and lower (7) tables supported by the side frames, one of the upper and lower tables serving as a vertically movable ram, and dies (17,19) disposed in a processing zone between the upper and lower tables (5, 7), for processing a plate material (W). A back gauge unit (41) is moved and positioned in longitudinal directions to position in the longitudinal directions the metal sheet (W) to be processed by the dies (17, 19). A die storage section (37) is defined behind the upper table (5). Part of the back gauge unit (41) is vertically movable and capable of supporting and replacing the dies (17, 19) between the die storage section (37) and the processing zone.

Abstract: A process a plate workpiece with high precision at high speed, the plate processing machine comprises a workpiece side surface positioning device (SPD) provided with magnet rollers (MR); a workpiece trimming device (TD) provided with a tool actuating switch (SW); and a workpiece positioning device (PD) provided with an optical sensor (SE). The magnet rollers guide a workpiece forward in magnetic rotatable contact engagement with the side surface of the workpiece. The tool actuating switch is actuated before the workpiece is located at a trimming position for automatic trimming operation. The optical sensor generates a feed speed deceleration signal so that a fed workpiece will not apply shock to the stop member of the positioning device by adjusting the sensor position relative to the stop surface according to the workpiece length to be cut.