TOWER CRANE Russian patent published in 2014 - IPC B66C13/10 

FIELD: transport.

SUBSTANCE: tower crane includes chassis, support-rotary device, rotary platform, tower, counterweight, jib, bracket-strut with guiding blocks and air screw installed at the end of beam, oriented in vertical plane and provided with adjustable drive with control system. The bracket-strut is provided with additional horizontal bracket at the end of which the second air screw is installed being oriented in vertical plane, provided with reverse adjustable drive connected with control system of the first screw and working in contrarotation with it, and air floe power of each screw is inversely proportional to distance from its rotation axis to pivotal axis of rotary platform.

EFFECT: optimised load at crane mechanisms and elements in jib turn.

1 dwg