Abstract: A fairlead mechanism for guiding a dragline drag rope includes a support on the chassis of the dragline and a guide mechanism mounted on the support. The guide mechanism includes at least one pair of guide sheaves each having an annular groove. The guide sheaves are rotatably mounted on the support to present the grooves in facing relation to define between the sheaves a guide path through which the drag rope passes in primary frictional contact with at least one of the guide sheaves to cause the contacted guide sheave to start-stop cycle between rotating and nonrotating modes as the drag rope reciprocates during operation of the machine. The fairlead mechanism further comprises a synchronizing mechanism utilizing gears or belts for causing the pair of guide sheaves to simultaneously stop or counterrotate in unison in response to rope contact with either one of the guide sheaves to minimize wear that would be induced by scrubbing between the rope and the guide sheaves.

Abstract: A dragline comprises a main chassis, a mechanism for moving the main chassis over the ground, a boom mounted on the main chassis, a sheave rotatably mounted on the boom, a dragline bucket, a hoist rope reeved over the sheave and having an end connected to the bucket to raise and lower the bucket, a drag rope connected to the bucket to pull the bucket toward the main chassis and to allow the bucket to move away from the main chassis, and an operator station on the main chassis, the operator station including a control lever apparatus for permitting an operator to control one of the mechanism, the hoist rope and the drag rope.

Abstract: The invention relates to a machine having a driven gear, service access to which is partially obstructed. An aspect of the invention involves an aperture permitting access to the driven gear through a spatial area away from the obstructed region. The driven gear includes a plurality of arc-like segments mounted on a spider for removal individually and the dimensions of at least one segment and the aperture are cooperatively selected to permit a segment to be removed through the aperture to the spatial area. Segments of the driven gear may thereby be removed for service while yet avoiding removal of the driving gear or other substantial disassembly. A method for replacing the driven gear includes forming the aperture, detaching a segment and removing the segment through the aperture to the spatial area.

Abstract: The invention involves a machine, e.g., a walking dragline having a drive gear, a driven member which loads (and wears) gear teeth unequally and an interconnecting shaft. The quill-mounted gear is separately supported by bearings. The shaft can be moved axially and when so repositioned, it is also separately supported by other bearings. When the gear needs to be "indexed," (due to unequal tooth wear) the shaft is moved axially out of connection with the gear but remains connected to the eccentric. The gear can then be indexed using its drive motor and the shaft can be re-engaged with the quill without the necessity of auxiliary lifting equipment and without disengaging the shaft from the eccentric.