Crane to operate with a screwdriver mechanism has a platform, a tie-bar, a crane trolley, a bogie truck and a tower made up of assembled elements with a toothed guide rail

摘要

A tower (1) with elements (11) contracting with a pulling mechanism (24) with a chain made up of pistons (25) and hinged links (23) can pull in onto a drum (26) to transport a crane. A gripper (27) links the drum to an upper element. A platform (4) moves downwards. The drum rotates and moves along its axis. The pulling mechanism turns out and the chain becomes slack.