Hoist rope for a hoist system

Abstract

A hoist system is provided for an industrial machine. The hoist system includes a hoist rope having an end secured to a hoist drum, and an end termination for securing the hoist rope to the hoist drum. The hoist rope is configured to be coupled to a digging attachment of the industrial machine. The hoist rope includes a first portion proximate the end termination and a second portion that is positioned between the first portion and the digging attachment. The first portion has a coefficient of friction that is higher than the second portion.

What is claimed is: 
     
         1 . A hoist system for an industrial machine including a digging attachment, the hoist system comprising:
 a hoist drum;   a hoist rope including an end secured to the hoist drum, the hoist rope configured to be coupled to the digging attachment; and   an end termination for securing the end of the hoist rope to the hoist drum,   wherein the hoist rope includes a first portion proximate the end termination and a second portion that is positioned between the first portion and the digging attachment, the first portion having a coefficient of friction that is higher than the second portion.   
     
     
         2 . The hoist system of  claim 1 , wherein the hoist drum includes one or more grooves configured to receive the hoist rope. 
     
     
         3 . The hoist system of  claim 1 , wherein the end termination includes a fitting secured to the end of the hoist rope and a ferrule attached to the hoist drum and configured to receive the fitting, wherein the fitting has a recessed portion for engaging a retainer. 
     
     
         4 . The hoist system of  claim 3 , wherein the ferrule has a tapered opening for receiving the fitting. 
     
     
         5 . The hoist system of  claim 3 , wherein the fitting has a tapered end configured to be received in the ferrule. 
     
     
         6 . The hoist system of  claim 1 , wherein a portion of the hoist rope is wrapped around the hoist drum in a first rotational direction, wherein the hoist drum includes a peg, wherein another portion of the hoist rope spaced apart from the end termination is wrapped around the peg to reverse the wrap direction to a second rotational direction that is substantially opposite the first rotational direction. 
     
     
         7 . The hoist system of  claim 1 , wherein the first portion of the hoist rope includes a cover extending around an inner portion of the hoist rope, the cover having a higher coefficient of friction than the inner portion. 
     
     
         8 . The hoist system of  claim 1 , wherein a surface of the hoist drum engaging the first portion of the hoist rope includes one of a thin polymer treatment, a flame-spray material deposit, and a coating (e.g., an oxide or other material) to increase a coefficient of friction of the hoist drum. 
     
     
         9 . The hoist system of  claim 1 , wherein a surface of the hoist drum engaging the first portion of the hoist rope includes a shot peen or media to increase a coefficient of friction of the surface and minimize sharp edges. 
     
     
         10 . The hoist system of  claim 1 , wherein the first portion of the hoist rope includes a diameter that is smaller than a diameter of the second portion of the hoist rope. 
     
     
         11 . The hoist system of  claim 1 , wherein a roller is positioned adjacent an outer surface of the hoist drum, the roller configured to inhibit the hoist rope from coming off of the hoist drum. 
     
     
         12 . A rope shovel including the hoist system of  claim 1 , the rope shovel including a boom and a handle supported on the boom, the handle supporting the digging attachment. 
     
     
         13 . A hoist system for an industrial machine including a digging attachment and a hoist drum, the hoist system comprising:
 a hoist rope including an end configured to be secured to the hoist drum, the hoist rope configured to be coupled to the digging attachment;   an end termination positioned at the end of the hoist rope; and   a ferrule coupled to the hoist drum, the ferrule engaging the end termination to secure the end of the hoist rope relative to the hoist drum,   wherein the hoist rope includes a first portion proximate the end termination and a second portion that is positioned between the first portion and the digging attachment, the first portion having a first rope diameter that is smaller than a second rope diameter of the second portion.   
     
     
         14 . The hoist system of  claim 13 , wherein a portion of the hoist rope is configured to be wrapped around the hoist drum in a first rotational direction, the hoist system further comprising a peg positioned on the hoist drum, wherein another portion of the hoist rope spaced apart from the end termination is wrapped around the peg to reverse the wrap direction to a second rotational direction that is substantially opposite the first rotational direction. 
     
     
         15 . The hoist system of  claim 13 , wherein the end termination is configured to engage a first portion of a surface of the hoist drum having a higher coefficient of friction than a second portion of the surface of the hoist drum that is spaced apart from the end termination of the hoist rope. 
     
     
         16 . A hoist rope configured for use with a hoist system including a hoist drum, the hoist rope comprising:
 a synthetic core configured to transmit a tensile load;   an outer jacket encasing the synthetic core;   an end termination including a fitting secured to an end of the hoist rope, the fitting configured to be secured to a ferrule attached to the hoist drum; and   a recessed portion positioned on an outer surface of the fitting, the recessed portion configured to engage a retainer for securing the fitting to the ferrule.   
     
     
         17 . The hoist system of  claim 16 , wherein a portion of the fitting has a cylindrical shape, wherein the end of the hoist rope is secured within an interior of the cylindrical shape. 
     
     
         18 . The hoist system of  claim 16 , wherein the fitting has a tapered end configured to be received in the ferrule. 
     
     
         19 . The hoist rope of  claim 16 , wherein a portion of the outer jacket proximate the end termination has a higher coefficient of friction than another portion of the outer jacket that is spaced from the end termination. 
     
     
         20 . The hoist system of  claim 16 , wherein the hoist rope includes a first portion proximate the end termination and a second portion that spaced from the end termination, the first portion having a first rope diameter that is smaller than a second rope diameter of the second portion. 
     
     
         21 . A hoist system for an industrial machine including a digging attachment, the hoist system comprising:
 a hoist drum;   a hoist rope including an end secured to the hoist drum, the hoist rope configured to be coupled to the digging attachment; and   an end termination for securing the end of the hoist rope to the hoist drum,   wherein the hoist rope includes a first portion proximate the end termination and a second portion that is positioned between the first portion and the digging attachment;   wherein a surface of the hoist drum has an original coefficient of friction, and wherein a modified portion of the surface of the hoist drum has a modified coefficient of friction that is higher than the original coefficient of friction.   
     
     
         22 . The hoist system of  claim 21 , wherein the modified portion of the surface of the hoist drum engages the first portion of the hoist rope. 
     
     
         23 . The hoist system of  claim 21 , wherein the modified coefficient of friction is 0.15 or higher. 
     
     
         24 . The hoist system of  claim 21 , wherein the modified portion of the surface of the hoist drum includes one of a thin polymer treatment, a flame-spray material deposit, and a coating (e.g., an oxide or other material) to increase the modified coefficient of friction. 
     
     
         25 . The hoist system of  claim 21 , wherein the modified portion of the surface of the hoist drum includes a shot peen or media to increase the modified coefficient of friction and minimize sharp edges.