Crane load swinging damping drive mechanism - reduces travel or slewing speed with increasing load

摘要

The drive mechanism is for use with slewing and gantry cranes with rope hoist mechanisms, to damp out load swinging. Above a predetermined capacity of the drive to the slewing or gantry crab travel mechanism and with increasing load, the speed of this mechanism is automatically reduced, and with decreasing load it is raised. Where the crane is hydraulically driven, the two main pipes (20, 21: via a two-way valve (23). As the system can be connected to a regulator (24) via a two-way valve (23). As the working pressure rises, this automatically reduces the output of the variable delivery pump (21). Alternatively, an electric Ward Leonard drive RTM can be used, a voltage being derived from one of the cables proportional to the current value. This acts via a rectifier on a regulator, weakening the field of the dc generator as current increases.