DEVICE FOR HOLE MAKING IN GROUND Russian patent published in 2002 - IPC

FIELD: means of mechanization of civil engineering work. SUBSTANCE: lower part of device shaping body has chambers located one above the other and separated by lateral bulkhead. These chambers are filled with fluid and constantly communicated by means of hole whose diameter is essentially equal to diameter of working end of striking piston. The latter is installed for limited longitudinal motion and periodic entering the lower chamber through said hole, at end of stroke. Upper chamber upper part provided with circular bead on internal side surface, has constantly located movable end of striking mechanism body with through radial windows in side wall. Lower part of striking mechanism body end has circular projection on its external surface. Side surface of circular projection is constantly conjugated with mating internal side surface of upper chamber and its end surfaces are located for alternating contacting with turned to them end surface of lateral bulkhead in extreme lower position and with circular bead in extreme upper position of said body end in upper chamber. In addition, external surface of body on part between through windows and circular bead is made in form of cone and forms circular slot of variable width together with circular bead. Said chamber is constantly communicated with space of shaping body through said circular slot. Device is applicable in making cast-in-place piles in industrial and civil engineering and also in compacting the ground and improvement of ground structure. EFFECT: enhanced efficiency and reliability of device. 1 dwg