Punch press and method of punching plate-type workpiece by the press

A punch press comprising:

• a frame;
• upper and lower turrets rotatably supported on the frame;
• a punch holder rotatably supported on the upper turret, for supporting a plurality of punch tools;
• a die holder rotatably supported on the lower turret, for supporting a plurality of die tools;
• each of the punch tools cooperating with one of the die tools in order to process a workpiece;
• a vertically movable ram mounted on the frame;
• and
• a striker mounted on the ram so as to be horizontally movable relative to the ram, wherein the striker is adapted to be movable to any position above the punch and die tools mounted on the punch and die holders when the punch and die holders are located substantially beneath the ram by rotation of the turrets;
• wherein the punch holder and die holder are rotatable at least 90 degrees relative to the upper and lower turrets, and a two-dimensional area in which the striker is movable covers every position to which at least one of the punch tools mounted on the punch holder is movable and to which a die corresponding to the at least one punch is movable when the punch and die holders are rotated 90 degrees.

A punch press comprising:

• tool holder supporting portions;
• a punch holder and a die holder each rotatably mounted on the supporting portions, said punch holder carrying a plurality of punch tools, said die holder carrying a plurality of die tools, and each of the die tools cooperating with one of the punch tools in order to punch a workpiece;
• a vertically movable ram mounted on a punch press frame;
• a revolving body mounted on a lower end of the ram so as to be rotatable about a vertical axis of the ram;
• a first striker mounted on the lower end of the revolving body, the first striker being located at a position in a peripheral region of the revolving body;
• wherein the striker located at a position in a peripheral region is a first striker and the punch press further comprises a second striker mounted on the lower end of the revolving body, the second striker located at the center of the revolving body;
• and
• wherein the punch holder and die holder are rotatable at least 90 degrees relative to the tool holder supporting portions, and an area in which the striker is movable covers every position to which at least one of the punch tools mounted on the punch holder is movable and to which a die corresponding to at least one punch is movable when the punch and die holders rotate 90 degrees.