| 摘要 |
PURPOSE:To check an undesirable automatic start by making a tool to be detected at a work place long enough to invalidate the output signal of the 2nd detector by the output signal of the 1st detector. CONSTITUTION:A tool 3 which is to be detected by the 1st detector 4 at a work place A is long, and a tool 3' to be detected at a stop position before a branch point is short. When the short tool 3' is detected by the detector 4, a stop commanding device operates to stop a dolly 2, but the detector 4 passes through the tool 3' because of the movement of the dolly 2 from the detection point to the stop point in time. Therefore, when the 2nd detector 6 detects a trailing dolly, a start commanding device is operated for an automatic start. On the other hand, when the long tool 3 is detected by the detector 4, the dolly 2 stops, but tool 3 is longer than the movement distance of the dolly 2 within the time from the detection to the stopping point, so the tool 3 is held in a detection operation state continuously by the detector 4 even when the dolly is stopping. Consequently, even when the detector 6 detects the trailing dolly, the dolly 2 is still stopping. |
