| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a machine operation panel capable of conforming to safety regulations on a machine out of the safety regulations without requiring any additional I/O unit or switch as well as requiring no changes in operability of the machine operation panel.SOLUTION: A machine operation panel 40 includes a key switch 42 which has double contacts, and the machine operation panel 40 has two independent communication circuits 44 and 46. The two independent communication circuits 44 and 46 receive signals from the double-contact key switch 42. The two independent communication circuits 44 and 46 transfer the signals to a numerical control unit 10 through a bus 30 capable of transferring safety-related signals. The numerical control unit 10 compares the received signals to monitor the soundness of the safety functions to conform to the safety regulations.</p> |
