| 摘要 |
PROBLEM TO BE SOLVED: To synchronize a plurality of devices which are synchronized with common synchronizing signals, and perform synchronization processing at a processing cycle which is longer than a cycle of the synchronizing signal.SOLUTION: One safety drive unit 3A out of a plurality of safety drive units has a master safety device 3A-3, and the other safety drive units 3B, 3C have slave safety devices. The master safety device and the slave safety devices are synchronized with synchronizing signals &phgr; outputted by a controller 1, respectively, and cyclically perform safety control at a processing cycle of k-times (k is an integer of 2 or more) of a cycle of the synchronizing signal. The master safety device transmits a multi-cast signal MC indicating the generation timing of the synchronizing signal which is synchronized with the processing cycle of the device, and the slave safety device synchronizes the cycle of the device to the synchronization signal &phgr; which is generated together with the multi-cast signal MC. |
