| 摘要 |
PROBLEM TO BE SOLVED: To solve following problems that in conventional pump dredges and clamshell buckets, not only target objects but also objects around the target objects are sucked or held by them, and in screw conveyors, only water is sucked therefore earth is blocked or large stones stop the screw therefore conveyance operation is interrupted.SOLUTION: By adjusting a ballast tank according to depth of deposits, the water serve boat is subjected to sink-and-float, and a diver injects only target objects by using an air gun, and the objects are sucked and conveyed by an air lift. |
