Fairlead mechanism with synchronized sheaves

摘要

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.