MECHANICAL-HYDRAULIC MACHINE FOR THE DREDGING OF HARBOURS, RIVERS, CANALS, SWAMPS, LAKES AND BEACHES, AT GREAT DEPTHS

摘要

The invention relates to a dredging machine which is based on a traditional backhoe excavator, but without a scoop. According to the invention, the free end of the working beam is provided with a set of movable pulleys serving as guides for the passage of cables that can be used to support tools such as hydraulic tools, grabs and clamshell buckets, such that very great depths of 50 metres and more can be reached. The cables extending through the above-mentioned movable pulleys are supplied by capstans provided with drums and located at the rear end of the working beam, said capstans being actuated from controls in the cab of the machine. In addition, the main rocker arm of the machine includes reels that supply hydraulic hoses having a length corresponding to that of the above-mentioned cables, which hoses are moved together with the cables and which, like the cables, terminate in the working tool. In this way, the tool does not close under the force of gravity and, consequently, with minimum closing pressure, as normally happens, but instead closes in a pressurised manner, using controls provided in the cab of the machine, synchronised by means of solenoid valves calibrated to the required pressures, such that the effectiveness of the tool is considerably improved.