GRAB Russian patent published in 1997 - IPC

FIELD: load-handling operations. SUBSTANCE: the grab uses a frame, control hydraulic cylinders, jaws and links in the form of two connecting rods installed symmetrically to frame longitudinal axis and whose lower ends are hinge-joined to upper ends of levers, two cranks whose lower ends are hinge-joined to frame, and two tie-rods whose lower ends are hinge-joined to free ends of levers, and upper ends, to cranks. The latter are hinge-joined to connecting rods in the point dividing connecting rod into two equal parts each part is equal to the part of crank between its hinge on frame and hinge between crank and connecting rod. Jaws are linked to levers for their joint movement along a straight line perpendicular to the frame longitudinal axis. Grab is furnished with two bars, one end of each bar is hinge-joined to upper end of the connecting rod, and the other end, to the crank located on opposite side of the frame forming with respective crank the like sides of symmetric parallelograms supported as cantilevers on connecting rods in their lower part by brackets; hinge-joined between free ends of the connecting rods and free ends of cranks are rods and barrels of control hydraulic cylinders installed for movement along frame longitudinal axis by a slide and pushers, whose one ends are hinge-mounted on slide, and the others, on cranks. EFFECT: enhanced efficiency. 2 cl, 4 dwg