摘要 |
<p>A punch press having a die formed with a diehole and mounted on a die holder and a punch set provided with a punch mounted on a punch holder for performing a punching process on a workpiece in cooperation with the die. The punch set is formed with a fluid discharge orifice for discharging a fluid into the diehole, and the punch is formed with a communication orifice communicating with the fluid discharge orifice. A ram for striking the punch is formed with a fluid supply orifice for freely communicating with the communicating orifice. A connecting pipe connects the fluid supply orifice with a fluid source; a shut-off valve is provided for opening or shutting of the connecting pipe, with a stroke position detector for detecting the stroke of the ram. A shut-off valve control is provided for controlling the opening or shutting of the shut-off valve according to the values detected by the stroke position detector.</p> |