DEVICE FOR DESTRUCTION OF OVERSIZED ROCKS Russian patent published in 2007 - IPC F42D3/04 

FIELD: drilling and blasting operations, applicable for destruction of big rock lumps (oversizes) separated from the rock mass both in open pits and in the underground conditions.

SUBSTANCE: the device has an explosive in a shell in the form of an elongated shaped charge with a metal foil located in the shaped recess of the shaped charge, and a fuse of an initiating explosive in the form of a cartridge, and a U-shaped body with air pockets located in the vertical walls and coupled to the chamber of the body by openings, piston installed inside the chamber, the piston is made with a recess and of two parts separated by a damping spacer. The upper surface of the piston is provided with vertical guides and damping springs. The U-shaped body is made of two parts: the upper and lower ones fixed by locks and provided with a damping spacer made on the whole inner surface of the body chamber. Two pairs of double-link catches are fastened on the outer lateral surfaces of the upper part of the body: two on each side located symmetrically relative to the longitudinal axis of the rock oversized lump, opposite each other, for pressing the device to the rock lump. Each double-link catch is made of a longer and shorter links and base located on the upper part of the body and linked to the longer link by an axle. The shorter link has a gripper with a rubber cup at the end, guide, yoke, hinge with a spring. Two lateral recesses for fixing of the locks are made on the outer surface of the body lower part, and a rubber sealing collar is fastened around the edges of the base of the body lower part.

EFFECT: enhanced efficiency of destruction at a lower quantity of the explosive due to fixation of the device directly on the oversized lump; pressing of the device directly to the oversized lump reinforces the action of the cumulative knife, and the gases directed towards the knife act on the oversized lump by enhanced pressure and destruct it.

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