Device for removal of gravel and soil from the water filled drill hole, comprising of case, container with back pressure flap at bottom, and vacuum creating piston element

摘要

The container (4) for the removal of gravel and soil from the water filled drill hole is accommodated inside a case (3), which is positioned with its lower end on the bottom of the hole. The bottom of the container (4) is constructed as a back pressure flap (5), letting the material and the liquid enter the container (4) but not return into the hole. A piston element (7) can be moved vertically inside the case (3), but not inside the container (4), creating a vacuum, which results in a flow of material and water into the container (4).