According to the US Patent and Trademark Office: “The invention concerns a suspension for load hooks, especially for lower blocks of cable controls, with a shaft mounted in a recess of a carrier body and able to turn about a vertical axis, which is mounted in a continuous bore of a support element and thrusts against the carrier body by means of at least one axial bearing.”

An abstract of the invention, released by the Patent Office, said: “In order to create a short and simple construction of a suspension for a load hook, the invention proposes that the shaft of the load hook is mounted in the carrier body by a bearing arrangement consisting of the support element, at least one axial bearing, and the retaining ring surrounding the shaft, and the bearing arrangement is secured by a fastening element, especially a snap-ring, in the carrier body.”

The inventors were issued US Patent Number 7,219,937 on May 22 2007.

The patent has been assigned to Demag Cranes & Components GmbH, Wetter.

The original application was filed on March 3 2004.