US Patent 7722013 Combination double bottom block

The invention relates to a combination double bottom hook block in which two pulley blocks (2, 3) each with a plurality of pulleys are connected to one another by means of a rocker (1), a load hook being mounted in a pivotable manner on the rocker. If use is made here of two lifting cables, each of these lifting cables is led over a pulley block (2, 3) and, in order to achieve the same loading capability if use is made of just one lifting cable, the latter is led, in addition, over a floating pulley (2) which is mounted between the two pulley blocks (2, 3), the two pulley blocks (2, 3) also being secured against tilting.