| 摘要 |
PROBLEM TO BE SOLVED: To provide a workpiece holding device for repositioning of a punch press, which enables a workpiece to be regripped if only the workpiece is present near the press position and which prevents a hit mark from being caused regardless of the thickness or the material of the workpiece. SOLUTION: The eccentric shaft 20 for vertically moving a punch press ram 22 and the main rotor shaft of a servo motor 30 are integrated, so that the servo motor is designed to directly drive the eccentric shaft. The device is equipped with a repositioning die 2 which is mounted on an arbitrary die station, a contact position detecting means 52 which detects the position where a punching die comes into contact with the upper face of a workpiece on the basis of the current change of the servo motor 30 at the time of punching operation, and a stop command generating means 53 that instructs stoppage of the servo motor 30 when the rotation detecting output of the servo motor 30 from the original position of the ram 22 reaches a value corresponding to the contact position obtained preliminarily from the contact position detecting means 52 at the time of use of the repositioning die 2. COPYRIGHT: (C)2004,JPO
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