| 摘要 |
PURPOSE:To detect a breakage of a punch in real time and to eliminate the waste of a workpiece by providing an air supply tube on a receiving hole side wall of a die, whereby a breakage of the punch is detected according to the air condition when the punch is intruded into the tube. CONSTITUTION:A green sheet 3 is transferred to a designated position, and in timing to the transfer, a punch driving signal for a selected punch 1 is output, whereby the corresponding punch 1 is driven to conduct punching machining. When the punch select driving signal is sent to a detecting portion 12, the detecting portion 12 makes reference to an air pressure signal sent out from a corresponding sensor 6 at that time or after the lapse of designated time, to discriminate in such a manner that if there is a fluctuation, the punch 1 is normal, and if not, the punch is broken. In the case where there is a breakage, a warning is given, and when a punch breakage detecting signal and a punch number are informed as breakage information to a control portion 11, the control portion 11 stops transfer of the green sheet 3 and the whole driving control for the punch 1. |
