| 摘要 |
PURPOSE:To raise the efficiency of dredging work by a method in which paired right and left-handed sub-ladders which can be turned are provided to the tip portion of the main ladder, and cutters turnable to opposite directions are provided to the tip portions of the sub-ladders. CONSTITUTION:When driving a motor 14, a rotary cutters C and C' are turned to mutually opposite directions through a cutter reduction gear 15, a cutter drive shaft 16, an universal joint 18, and a spline shaft coupler 22. In the excavating work of right-side swing mode, excavation is made by cutting the ground from below to above by the left-directed rotary cutter 20 in the first place, and then by dredging the ground from above to below by the right-directed rotary cutter 19. Also, in the excavating work of left-side swing mode, excavation is made by cutting the ground upwardly by the cutter 19 in the first place and then by dredging the ground by the cutter 20. Even in either case of right and left-side swing modes, upward-cutting excavation work is made possible to enable dredging excavation work to be performed only by one-time operation. |
