| 摘要 |
PURPOSE:To reliably detect movement of a swing anchor, by a method wherein, in a dredger which performs a dredging work through swing of a ship hull, a difference in speed between swing wires on the winding side and the unwinding side is detected. CONSTITUTION:The numbers of revolutions of swing winches 7 and 8 are detected by detectors 20 and 21 for the number of revolutions of a swing winch to input the result to a number of revolutions comparator 22. In the number of revolutions comparator 22, the total sum of the number (a positive number) of revolutions of a swing winch on the winding side and the number (a negative number) of revolutions of a swing winch on the unwinding side, and the resultant value is inputted to a number of revolutions deciding device 23. When swing anchors 11 are 12 are not moved, i.e., during usual swing, the total sum is zero, but when either the swing anchors 11 or 12 is displaced, the total sum becomes away from 0. Further, when the total sum exceeds a given value, the number of revolutions deciding device 23 actuates an alarming device 24 to report movement of the swing anchors 11 and 12. |
