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.