Ship loading boom installation having loading and suspension tackles and automatic guide blocks for positioning the suspension tackle by the load tackle

Claim 1

Ship loading installation of the type wherein a boom having a boomhead is pivotably arranged on a ship''s deck between two side posts fixed to the deck, for loading operations on either side of a vertical center plane which passes through the side posts, and suspension tackle extends between the boomhead and each side post, while load tackle passes from one side post to upper and lower load blocks suspended from the boomhead and then to the other side post; said installation comprising: a pair of rigid arms symmetrically extending a short distance from the boomhead, generally toward the side posts; a pair of first swivel bearings, one on each side arm, each bearing extending across the arms along the boom and having an extension piece at a free end of the bearing; a suspension block on each of these extension pieces, each block being pivoted to the extension piece for swinging in a plane which includes the swivel bearing, and each block having pulleys, for the suspension tackle; a pair of second swivel bearings, one on each suspension block, extending generally in the direction of the suspension tackle; a guide block on each suspension block, pivoted to the last mentioned swivel bearing of the block and having a guide pulley, in a plane parallel to the suspension tackle and to the load tackle portion extending to the side post; whereby the load tackle can be brought from the side posts over the guide pulleys to the load blocks, so that the load tackle, through the several swivel bearings, keeps the suspension blocks in such positions that the suspension tackle will not be twisted when the boom is swung through the center plane by the load tackle.