Patent ID: 6081292
Filing Date: 2000-06-27
Classification: B66C

Abstract:
A gantry crane having frame and a vertically movable grappler supported by the frame, the grappler being operable to engage and lift a container, the grappler having a plurality of twistlocks positioned to engage locking holes in a container, the gantry crane also having a grappler positioning system including:at least two video devices mounted to the grappler at respective corners of the grappler near the twistlocks;at least one monitor operable to display a video image from at least one of the video devices;a plurality of alignment sensors, each alignment sensor being mounted near a respective side of the grappler between two of the twistlocks for sensing a relative position of a respective side of a container vertically below; andan indicator actuatable by a respective one of the alignment sensors to indicate when the respective side of the grappler is aligned vertically over the side of the container.