| 摘要 |
A die (13, 213, 313) is supported in a die holder (381) such as a frame or an adapter (18, 518) supported in a frame such that it is operational use in a material deforming operation. One or both of the die and the die holder have at least one gas passage which is substantially closed by at least part of the die. Gas such as pressurized air is directed into an end of the gas passage opposite the die via a hose (42, 542) connected to a gas source. If the die is broken or loose leak paths are available for the escape of gas past the die to or from atmosphere. A pressure sensor (41) connected to the hose detects the change in pressure of the gas and the magnitude of that pressure is used to determine the die condition. Alternatively a flow rate sensor is used to detect a change in the flow rate of the gas in order to determine the condition of the die. |
