Overhead crane with lifting beam provided with C-shaped claws

Claim 1

In an overhead crane with a lifting beam provided with C-shaped claws, said crane having a load trolley on top of which there is a small load crab provided with a load hoisting unit and being rotatable about a vertical axis, the load hoisting unit having a tilting unit, the improvement which comprises: means for lifting and loading the lifting beam, such means comprising a plurality of pairs of wire ropes having runs inclined with respect to each other, the starting ends of such ropes being secured to the load crab, and a balance system comprising first pulleys mounted on the lifting beam and additional second guiding pulleys being mounted on said load crab, and winding drums mounted on said load crab, the wire ropes being driven by said winding drums, the ropes after being entrained over said first pulleys of the balance system and being guided about said second guiding pulleys being wound upon the driven drums, and means selectively to correlate the tilting and rising movements of the lifting beam, said last-named means comprising a further pair of wire ropes having runs inclined with respect to each other, such further pair of wire ropes having their starting ends attached to the winding drums and guided by being entrained over pairs of third guiding pulleys mounted on said load crab, the opposite ends of the further wire ropes being entrained over fourth pulleys, the center of rotation of said fourth pulleys being located on one side of and at a distance from the longitudinal center line of the lifting beam, the fourth pulleys being located as near as possible to the horizontal plane passing through the centers of rotation of the first pulleys of the balance system on the lifting beam, a tilting mechanism having a driven rope winding drum, the further ropes after leaving the fourth pulleys being wound round the driven ropes winding drum of the tilting mechanism said fourth pulleys being used for both lifting and tilting and being pivotally connected by an attachment member to the C-shaped claws, the point of attachment of said attachment member of the C-shaped claws being located spaced from the longitudinal center line of the lifting beam on one side thereof.