Independently powered trolleys

摘要

A trolley control system for a gantry crane having a multiple trolley arrangement such as a first and second trolley. The control system including a trolley beam connected to the gantry crane with a first and second drive device connected to the trolley beam. The first drive device is powered by a first drive system while the second drive device can be powered by either the first drive system or the second drive system. A first trolley is connected to the first drive device while a second trolley is connected to the second drive device.