Apparatus for converting a wheeled vehicle to a tracked vehicle

Abstract

The invention relates to track systems that may be used to convert steerable, all-wheel drive construction equipment to steerable, multi-track construction vehicles. The track system may include a frame having a reinforcing enclosure, a plurality of track engaging rollers, a sprocket, and an endless track operatively connected to the frame. Tension on the endless track is maintained with two tensioning members operatively connected to the forwardmost roller. The track system preferably includes a limiting apparatus that is configured to restrict the rotational movement “r” of the frame relative to a vehicle axle to which it is attached. The limiting apparatus has a first component, which is associated with the vehicle axle, is configured and arranged to interact with a second component, which is associated with the frame of the track system. Preferably, the limiting apparatus is adjustable such that the range of rotational movement “r” can be varied.

What is claimed is: 
     
         1 . A track system comprising:
 a frame having a first end and a second end, the frame having first and second frame assemblies that extend between the first and second ends of the frame;   a drive sprocket mounted between the first and second frame assemblies, the drive sprocket being rotatable relative to the frame about an axis of rotation, the first frame assembly being inboard of the drive sprocket and the second frame assembly being outboard of the drive sprocket, the second frame assembly including two spaced-apart generally vertical plates;   a first end roller mounted at the first end of the frame;   a second end roller mounted at the second end of the frame;   a track routed in a generally triangular path about the drive sprocket and the first and second end rollers, the track being driven by the drive sprocket about the generally triangular path when the drive sprocket is rotated about the axis of rotation;   first and second tensioning members for moving the first end roller relative to the frame to tighten the track, the first tensioning member being operatively connected to the first frame assembly and the second tensioning member being operatively connected to the second frame assembly, at least a portion of the second tensioning member positioned between the spaced-apart plates;   the generally triangular path of the track having an apex, and the drive sprocket engaging the track adjacent the apex to drive the track about the generally triangular path;   the track defining a bottom side of the generally triangular path that extends between the first and second end rollers, the generally triangular path defining a height that extends from the bottom side of the generally triangular path to the apex of the generally triangular path, the drive sprocket having a diameter that extends a majority of the height defined by the generally triangular path;   a track hub connected to the frame, the track hub being configured to allow the drive sprocket to rotate relative to the frame, the track hub including a sprocket mounting flange.   
     
     
         2 . The track system of  claim 1 , wherein each tensioning mechanism is a fluid cylinder. 
     
     
         3 . The track system of  claim 1 , wherein the tensioning mechanism moves the first roller along a linear path relative to the frame to tighten the track. 
     
     
         4 . The track system of  claim 1 , wherein at least a portion of the first roller is positioned between the first and second frame assemblies, and where the first roller is mounted on a shaft supported by the first and second frame assemblies. 
     
     
         5 . The track system of  claim 4 , wherein the tensioning mechanism is operatively connected to the shaft on which the first end roller is mounted. 
     
     
         6 . The track system of  claim 1 , wherein the drive sprocket has a split configuration including at least first and second separate sprocket sections that are fastened to the sprocket mounting flange of the track hub, and wherein the first and second sprocket sections are hemispherical. 
     
     
         7 . The track system of  claim 6 , wherein each of the first and second sprocket sections include outwardly extending teeth, and wherein the first and second sprocket sections define fastener openings for receiving fasteners used to fasten the first and second sprocket sections to the sprocket mounting flange. 
     
     
         8 . The track system of  claim 1 , wherein the track system further includes first, second, third, and fourth intermediate rollers for supporting the track along the bottom side of the generally triangular path, and wherein:
 the intermediate rollers are positioned between the first and second frame assemblies;   each of the first, second, third, and fourth intermediate rollers are respectively mounted on first, second, third, and fourth cantilevered shafts;   the first and third cantilevered shafts are supported by the first frame assembly;   the drive sprocket passes between the first and second intermediate rollers and between the third and fourth intermediate rollers as the sprocket rotates about the axis of rotation.   
     
     
         9 . The track system of  claim 8 , wherein the respective first and second cantilevered shafts and the third and fourth cantilevered shafts are coaxially aligned. 
     
     
         10 . The track system of  claim 9 , wherein the first and second end rollers are positioned between the first and second frame assemblies and are mounted on end roller shafts each supported by the first and second frame assemblies. 
     
     
         11 . The track system of  claim 10 , wherein the first and second end rollers each include first and second flanges, and wherein the drive sprocket passes between the first and second flanges of the first and second end rollers as the drive sprocket rotates about the axis of rotation. 
     
     
         12 . The track system of  claim 11 , wherein:
 the first and second frame assemblies are interconnected at a first interconnection location positioned above the first end roller;   the first and second frame assemblies are interconnected at a second interconnection location positioned above the second end roller;   the first and second frame assemblies are interconnected at a third location positioned between the first and roller and the first and second intermediate rollers;   the first and second frame assemblies are interconnected at a fourth interconnection location positioned between the second end roller and the third and fourth intermediate rollers; and   the first and second interconnection locations include struts extending between the first and second frame assemblies.   
     
     
         13 . The track system of  claim 1 , wherein the track hub further includes a shaft that rotates with the sprocket mounting flange, the shaft being supported by a bearing which allows rotation of the shaft, the bearing being mounted within a housing connected to the second frame assembly. 
     
     
         14 . A track system comprising:
 a frame having a first end and a second end, the frame having first and second frame assemblies that extend between the first and second ends of the frame;   a drive sprocket mounted between the first and second frame assemblies, the drive sprocket being rotatable relative to the frame about an axis of rotation, the first frame assembly being inboard of the drive sprocket and the second frame assembly being outboard of the drive sprocket;   a first end roller mounted at the first end of the frame;   a second end roller mounted at the second end of the frame;   a track routed in a generally triangular path about the drive sprocket and the first and second end rollers, the track being driven by the drive sprocket about the generally triangular path when the drive sprocket is rotated about the axis of rotation; and   a tensioning mechanism for tightening the track;   wherein:
 the generally triangular path of the track has an apex, and the drive sprocket engages the track adjacent the apex to drive the track about the generally triangular path; and 
 the track defines a bottom side of the generally triangular path that extends between the first and second end rollers, the generally triangular path defining a height that extends from the bottom side of the generally triangular path to the apex of the generally triangular path, the drive sprocket having a diameter that extends a majority of the height defined by the generally triangular path. 
   
     
     
         15 . The track system of  claim 14 , wherein the tensioning mechanism comprises first and second tensioning members for moving the first end roller relative to the frame to tighten the track, the first tensioning member being mounted to the first frame assembly and the second tensioning member being mounted to the second frame assembly. 
     
     
         16 . The track system of  claim 15 , wherein the track assembly includes two spaced-apart generally vertical plates, and wherein at least a portion of the second tensioning member is positioned between the spaced apart plates. 
     
     
         17 . The track system of  claim 16 , wherein the tensioning members are fluid cylinders. 
     
     
         18 . The track system of  claim 14 , wherein:
 the drive sprocket has a split configuration including at least first and second separate sprocket sections;   each of the first and second sprocket sections include outwardly extending teeth; and the   first and second sprocket sections define fastener openings.   
     
     
         19 . A track system comprising:
 a frame having a first end and a second end, the frame having first and second frame assemblies that extend between the first and second ends of the frame;   a drive sprocket mounted between the first and second frame assemblies, the drive sprocket being rotatable relative to the frame about an axis of rotation, the first frame assembly being inboard of the drive sprocket and the second frame assembly being outboard of the drive sprocket, the second frame assembly including two spaced-apart plates;   a first end roller mounted at the first end of the frame;   a second end roller mounted at the second end of the frame;   a track routed in a generally triangular path about the drive sprocket and the first and second end rollers, the track being driven by the drive sprocket about the generally triangular path when the drive sprocket is rotated about the axis of rotation;   first and second force exerting members members for moving the first end roller relative to the frame to tighten the track, the first force exerting member being operatively connected to the first frame assembly and the second force exerting member being operatively connected to the second frame assembly, at least a portion of the second force exerting member positioned between the spaced-apart plates;   the generally triangular path of the track having an apex, and the drive sprocket engaging the track adjacent the apex to drive the track about the generally triangular path;   the track defining a bottom side of the generally triangular path that extends between the first and second end rollers, the generally triangular path defining a height that extends from the bottom side of the generally triangular path to the apex of the generally triangular path, the drive sprocket having a diameter that extends a majority of the height defined by the generally triangular path;   a track hub connected to the frame, the track hub being configured to allow the drive sprocket to rotate relative to the frame, the track hub including a sprocket mounting flange; and   a plurality of intermediate rollers for supporting the track along the bottom of the side of the generally triangular path, wherein the intermediate rollers are positioned between the first and second frame assemblies and are respectively mounted to cantilevered shafts supported by the first frame assembly or the second frame assembly, and wherein the drive sprocket passes through the intermediate rollers as the sprocket rotates about the axis of rotation.   
     
     
         20 . The track assembly of  claim 19 , wherein the force exerting members are fluid cylinders.