US Patent 7905299 Articulation assembly for moving a drill mast

A jib assembly for use with a drill rig includes a jib boom having a first end and a second end. The jib boom is to rotate about the first end and the second end is configured to be coupled to a mast assembly mount. The jib assembly also includes an articulation assembly having at least one variable length link having a first end and a second end. The first end of the variable length link is offset from the jib boom and the second end is configured to be pivotingly coupled to the mast assembly mount.