constant value by the pressure control valve 28 enabling to controll the board to press at a constant pressure further the pressing cylinder 5 is lifted up or lowered together with the metal mold attaching plate 4 by the punching cylinder 2 even when the pressing cylinder 5 moves in a small stroke an entire stroke can be increased therefore the board 15 can be readily attached to or detached from the dies more specifically even after the board is punched out the punching tool 26 may be moved upward and downward in reciprocation so that the inner surface of the hole can be finely finished punching residue is discharged from the die hole 25 although in the above stated embodiment shown in fig4 vibrating and punching operations are carried out two times however it is to be understood that they may be more repeated depending on the shape of a hole or the material of a board as illustrated in fig5 after one cycle vibrating and punching operation punching operations a reciprocating movement of the punching cylinder 2 may be repeated without applying a vibration while the board 15 is pressed by the pressing members 22 this method is more effective for the purpose of reducing the swelling parts on the inner surface of the hole rather than for the purpose of finishing the inner surface of the hole alternately in place of the pressing cylinder 5 as.