Overhead travelling crane running on cables - uses cables to support beam of crane which is moved by tractor cable and has moving counterweight in beam

摘要

The bridge of an overhead travelling crane is supported on cables rather than rigid rails with their associated support structures, removing limitations on height and terrain which arise with the fixed rail type crane. The crane has a travelling beam (1) fitted at each end with multiple pulleys (2). The pulley sets run on support cables (3), one at each end of the beam. The cables are fixed at their ends to buttresses. The crane is moved along the support cables by a tractor cable (4) with its ends fixed by yokes (5) to opposite sides of the beam, and passing over a fixed pulley (8) at one end of the crane traverse and over a pulley (6) driven by an electric motor (7) at the other end of the traverse. The hoist mechanism runs traversely across the beam and is cable connected to a counterweight which moves in the opposite sense. .