Abstract: A method for controlling the noise and vibration of machine tools in correspondence with environmental control standards includes determining a first level of noise and vibration generated by the machine tool during its operation, selecting a desired level of noise and vibration generated by said machine tool during its operation, and controlling the operation of said machine tool so that said machine tool operates at a second level of noise and vibration, wherein said second level of noise and vibration is below said desired level of noise and vibration. In a specific embodiment the stroke speed of the stroke section of a plate processing machine is controlled.

Abstract: To eliminate defects such as burr, rollover, sags, scar, etc. from cut-off surfaces of a workpiece in a turret punch press, for instance, a novel height-different punch formed with a lower front edge, an upper rear edge, and an intermediate edge extending between the two edges is used for the punch press. While feeding the workpiece on a horizontal plane in a predetermined direction, the punch is struck by a striker at a first stroke so that the lower front edge thereof cuts off the workpiece partially in cooperation with a die; at the succeeding strokes so that the intermediate edge thereof cuts off the workpiece mincingly and curls refuse within a recess of the die; and at the last stroke so that the upper rear edge thereof cuts curled refuse away from the workpiece to complete a multistroke punching operation.