In addition to the steel structure of the tower body, the tower crane is mainly composed of four major mechanisms: lifting, slewing, jacking, and luffing. Among them, the slewing mechanism of the tower crane is mainly composed of six parts, namely the electric motor, hydraulic coupling, built-in electromagnetic stopper, planetary gear reducer, driving pinion, and single-row ball slewing ring. In addition, safety devices such as a limit torque limiter, slewing buffer device and slewing limiter are installed in the slewing mechanism as required. In order to prevent the boom from slipping under the action of strong wind, the slewing mechanism is equipped with a stopper. However, the slewing mechanism should allow the boom to rotate freely with the wind in a non-working state.
The working principle of the slewing mechanism of the tower crane is to rely on the rotation of the boom to ensure its working coverage. The slewing motion is produced by installing the upper and lower slewing bearings on the inner and outer rings of the slewing bearing respectively, and the pinion gear is driven by the slewing mechanism, and the pinion gear meshes with the large gear of the slewing bearing, driving the upper slewing bearing to move relative to the lower bearing.
