Patent Publication Number: US-2015083834-A1

Title: Reducing twine wrap on bale processor shafts

Description:
This invention is in the field of agricultural bale processors for shredding baled crop material and in particular an apparatus for reducing the occurrence of twine wrapping on sprocket shafts of a bale drive chain in a bale processor. 
     BACKGROUND 
     In the livestock industry, large bales of crop material are formed and tied with twine, and then stored for use. Commonly a bale processor is then used to shred the bales and distribute the shredded material for feed and/or bedding. Such bale processors typically have a disintegrator roller longitudinally mounted for rotation inside a processing chamber. The disintegrator roller is rotated, and flails on the roller extend to engage a bale in the processing chamber, remove and shred material from the bale, and discharge the shredded material out of the processing chamber. 
     As material is removed from the bale, the bale gets smaller and so bale processors must include some mechanism for pushing the bale toward the disintegrator roller such that same continues to engage the flails. In one common type of bale processor, the disintegrator roller extends along one side of the bale chamber, and the bale rests on a chain and slat conveyor that extends the length of the bale chamber and moves laterally across the chamber moving the bale into the flails. Such chain and slat conveyor bale processors are disclosed for example in U.S. Pat. No. 5,368,238 to Bergkamp et al. and in U.S. Pat. No. 5,090,630 to Kopecky et al. 
     The chain and slat conveyor comprises commonly a driven shaft extending along one side of the bale chamber and an idler shaft extending parallel along the opposite side. Either the idler or driven shafts is mounted adjacent to the disintegrator roller, with the other shaft at the opposite side of the bale chamber. One of the shafts is movable to adjust chain tension. The conveyor comprises parallel slats extending the length of the bale chamber and fastened to chains which engage sprockets attached to the driven and idler shafts such that rotating the driven shaft moves the slats, and the bale resting thereon, toward the disintegrator roller. The floor of bale chamber is provided by a chain bed, and the slats and chains move toward the disintegrator roller across the top surface of the chain bed such that the bale is supported on the chain bed, and the return run of the conveyor is under the chain bed 
     Due to the length of the bale chamber and weight of the bale, three chains spaced apart at the front, middle, and rear of the bale chamber are conventionally used to support the slats and prevent bending thereof. Each of the idler and driven shafts thus has corresponding front, middle, and rear sprockets mounted thereon. The idler and driven shafts are supported on front, middle, and rear bearings which are located adjacent to the corresponding front, middle, and rear sprockets. The front and rear bearings are conveniently attached to the front and rear walls of the bale chamber, and the middle bearings are fixed to the chain bed. It is also known to rotatably mount three separate idler sprockets independently on separate front, middle, and rear bearings fixed to the bale chamber walls or the chain bed, such that there is no idler shaft as such. 
     Such chain and slat conveyors provide a simple and economical mechanism for moving the bale against the disintegrator roller, however a problem with the system is that the bales are shredded without removing the twine. Loose twine is thus always present in the bale chamber, and wraps around the driven and idler shafts adjacent to the sprockets and bearings, and between the chain and the sprockets. This twine must be removed periodically to prevent damage. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a chain and slat conveyor apparatus for a bale processor that overcomes problems in the prior art. 
     In a first embodiment the present invention provides a bale processor apparatus comprising a bale chamber, and a chain bed forming a bottom of the bale chamber. A disintegrator roller is rotatably mounted along a length of one side of the bate chamber. A driven shaft extends adjacent to a first side edge of the chain bed and front, middle, and rear drive sprockets are mounted to front, middle, and rear portions of the driven shaft. An idler shaft extends adjacent to a second side edge of the chain bed, and front, middle, and rear idler sprockets are mounted to front, middle, and rear portions of the idler shaft. The driven and idler shafts are supported only at front and rear ends thereof by corresponding front and rear bearings such that the sprockets and shafts rotate unsupported between the front and rear bearings such that twine wrapping on middle portions of the driven and idler shafts is reduced. Front, middle, and rear conveyor chains, each engage corresponding front, middle, and rear drive and idler sprockets such that a top run of each chain extends along a top surface of the chain bed and a return run of each chain extends under the chain bed. A plurality of conveyor slats are oriented substantially parallel to the driven and idler shafts and attached to the front, middle, and rear chains. 
     In a second embodiment the present invention provides a method of reducing the wrapping of twine on a chain and slat conveyor in a bale processor, the bale processor comprising a bale chamber; a chain bed forming a bottom of the bale chamber; a disintegrator roller rotatably mounted along a length of one side of the bale chamber; a driven shaft extending adjacent to a first side edge of the chain bed; front, middle, and rear drive sprockets mounted to front, middle, and rear portions of the driven shaft; an idler shaft extending adjacent to a second side edge of the chain bed; front, middle, and rear idler sprockets mounted to front, middle, and rear portions of the idler shaft; front, middle, and rear conveyor chains, each chain engaging corresponding front, middle, and rear drive and idler sprockets such that a top run of each chain extends along a top surface of the chain bed and a return run of each chain extends under the chain bed; and a plurality of conveyor slats oriented substantially parallel to the driven and idler shafts and attached to the front, middle, and rear chains. The method comprises supporting the driven and idler shafts only at front and rear ends thereof with corresponding front and rear bearings such that the sprockets and shafts rotate unsupported between the front and rear bearings and twine wrapping on middle portions of the driven and idler shafts is reduced. 
     Scraper devices can be mounted adjacent o front and rear sprockets to prevent he build-up of twine on the shafts. 
     The apparatus and method of the present invention thus reduce wrapping of twine on the chain and slat conveyor of a bale processor. Time and effort needed to remove twine is reduced, and the risk of damage from wrapped twine is reduced as well. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numbers, and where: 
         FIG. 1  is a schematic top view of an embodiment of a bale processor apparatus of the present invention, with the chains and slats removed to more clearly show the apparatus; 
         FIG. 2  is a schematic top view of the embodiment of Fig. with the chains and slats installed; 
         FIG. 3  is a schematic op view of an idler shaft of the prior art; 
         FIG. 4  is a schematic detail top view of the front end of e idler shaft of the embodiment of  FIG. 1 ; 
         FIG. 5  is a schematic detail front view of the front end of an alternate configuration of the front end of an idler shaft that could be used in the embodiment of  FIG. 1 ; 
         FIG. 6  is a schematic sectional end view of the idler shaft of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
       FIGS. 1 and 2  schematically illustrate an embodiment of a bale processor apparatus  1  of the present invention. The apparatus  1  comprises a bale chamber  3 , and a chain bed  5  forming a bottom of the bale chamber  3 . The bale chamber  3  is typically mounted on wheels for movement along the ground in an operating travel direction T. A disintegrator roller  9  is rotatably mounted along a length of one side of the bale chamber  3 . The disintegrator roller  9  is illustrated on the left side but could also be on the right side. The front and rear ends of the chain bed  5  are attached to front and rear walls  7 F,  7 R of the bale chamber  3  such that an open space is created under the chain bed  5  for passage of a chain and slat conveyor that continuously moves a bale of crop material toward the disintegrator roller  9 . 
     The chain and slat conveyor comprises a driven shaft  11  extending adjacent to a first side edge  13 A of the chain bed  5 , and front, middle, and rear drive sprockets  15 F,  15 M,  15 R mounted to front, middle, and rear portions of the driven shaft  11 . The drive shaft is driven by a hydraulic motor  17 , or like drive mechanism. 
     An idler shaft  19  extends adjacent to a second side edge  13 B of the chain bed  5 , and front, middle, and rear idler sprockets  21 F,  21 M,  21 R are mounted to front, middle, and rear portions of the idler shaft  19 . The driven and idler shafts  11 ,  19  are supported only at front and rear ends thereof by corresponding front and rear bearings  23 F,  23 R such that the sprockets  15 ,  17  and shafts  11 ,  19  rotate unsupported between the front and rear bearings  23 F,  23 R such that twine wrapping on middle portions of the driven and idler shafts  11 ,  19  is reduced. 
     Front, middle, and rear conveyor chains  25 F,  25 M,  25 R each engage corresponding front, middle, and rear drive and idler sprockets  15 ,  21  such that a top run of each chain  25 , visible in  FIG. 2 , extends along a top surface of the chain bed  5  and a return run of each chain extends under the chain bed  5 . A plurality of conveyor slats  27  are oriented substantially parallel to the driven and idler shafts  11 ,  19  and are attached to the front, middle, and rear chains  25 F,  25 M,  25 R as is known in the art. The chains  25  and slats  27  are shown in  FIG. 2  but have been deleted from  FIG. 1  to more clearly show the apparatus  1 . 
     An idler shaft  19 ′ of the prior art is schematically illustrated in  FIG. 3  with front, middle, and rear idler sprockets  21 F′,  21 M′,  21 R′ mounted to front, middle, and rear portions of the idler shaft  19 ′. The prior art idler shaft  19 ′ is supported at front and rear ends thereof in front and rear bearings  23 F′,  23 R′ and in addition is supported at a mid-point near the middle idler sprocket  21 M′ by a middle bearing  23 M shown mounted on a bracket  29  fixed to the chain bed  5 ′. Twine being carried over the rotating middle idler sprocket  21 M′ contacts the middle bearing, the bracket  29 , and protrusions thereon such as bolt heads, etc. and tends to catch and wrap around the idler shaft as the shaft continues rotating while the twine is held stationary by the fixed bracket  29  and bearing  21 M′. The driven shafts of the prior art are similarly supported by a middle bearing. 
     In contrast in the apparatus  1  of the present invention, there is nothing stationary in the middle of the driven or idler shafts  11 ,  19  that can obstruct twine and cause same to wrap. Twine being carried over the rotating middle idler sprocket  21 M just keeps going, and the occurrence of twine wrapping around the middle portion of the shafts  11 ,  19  is significantly reduced. 
     In the prior art the middle bearing is required to support the driven and idler shafts and prevent them from bending under the tension of the middle chain of the chain and slat conveyor. In the present invention such bending is prevented by increasing the size and strength of the shafts instead. 
     Thus in the apparatus  1  of the present invention, the driven and idler shafts  11 ,  19  are cylindrical and have a larger first diameter on main portions  11 A,  19 A thereof extending substantially from inner surfaces  31  of the front sprockets  15 F,  21 F to inner surfaces  31  of the rear sprockets  15 R,  21 R mounted thereon, and have a second smaller diameter on end portions  11 B,  19 B thereof that extend substantially from outer surfaces  33  of the front and rear sprockets  15 F,  21 F  15 R,  21 R into the front and rear bearings  23 F,  23 R. 
     Wrapping of twine about the middle portions of the shafts  11 ,  19  is reduced as described above by removing the stationary bearing  23 M and bracket  29 . At the ends of the shafts  11 ,  19  however the walls  7 F,  7 R and bearings  23 F,  23 R are of course stationary. The front and rear bearings  23 F,  23 R are mounted on the outside surface of corresponding front and rear walls  7 F,  7 R of the bale chamber  3  outside the bale chamber  3  to reduce Obstructions on the inner surfaces of the walls  7 F,  7 R. The end portions  11 B,  19 B of the driven and idler shafts  11 ,  19  extend through holes in the front and rear walls  7 F,  7 R and into the front and rear bearings  23 F,  23 R. 
     To further reduce wrapping of twine around the shafts  11 ,  19 , in the apparatus  1  of the present invention a scraper device  35  is mounted at each end of the shafts  11 ,  19 .  FIG. 4  schematically illustrates the scraper device  35  at the front end of the idler shaft  19  which is configured and mounted such that an outer scraping projection  37  thereof extends between the inside surface of the front wall  7 F and the outer surface  33  of the adjacent front idler sprocket  21 F such that an end edge of the outer scraping projection  37  is in proximity to the end portion  19 B of the shaft  19  carrying the sprocket  21 F, and side edges of the outer scraping projection  37  are in proximity to the inside surface of the front wall and the outer surface  33  of the sprocket  21 F. 
     In the illustrated apparatus  1  the diameter of the idler shaft  19  is reduced adjacent to the inner surface  33  of the sprocket  21 F such a that a recess  39  is formed. The scraper device  35  also has an inner scraping projection  41  separated from the outer scraping projection  37  by a gap  43  configured to allow the sprocket  21 F to rotate in the gap  43 . The inner scraping projection  41  extends into the recess  39  with edges thereof in proximity to the inner surface  31  of the sprocket  21 F and the shaft  19 . 
     Thus as the shaft  19  rotates, twine may begin to gather adjacent to the stationary walls  7  however the outer and inner scraping projections  37 ,  41  prevent same from building up, and thus reduce twine wrapping. 
     In the illustrated apparatus  1 , the idler shaft  19  and associated front and rear bearings  23 F,  23 R are mounted in slots through the front and rear walls  7 F,  7 R so that the shaft and bearings can be moved to adjust chain tension. The scraper devices  35  related to the movable idler shaft  19  are therefore also adjustable, for example as shown attached by bolts through slots in the walls  7  as well such that the close relationship between the outer and inner scraping projections  37 ,  41  and the sprocket  21 F and shaft  19  can be maintained. The driven shaft  11  is fixed, and so the scraper devices  35  related thereto can be attached to the fixed chain bed 
       FIGS. 5 and 6  schematically illustrate front and side views of an alternate configuration of the end of the idler shaft  19 ′ where the end portions  19 B′ have the same increased diameter as the main portion  19 A′. In the configuration of  FIGS. 5 and 6 , the distance D between the bottom of the links of the chain  25 ′ that is engaged on sprocket  21 ′ and the outer surface of the shaft  19 B is reduced, leaving less space for twine to gather. A scraper device  35 ′ is shown attached to the wall  7 . 
     The invention thus provides a method of reducing the wrapping of twine on a chain and slat conveyor in a bale processor by supporting the driven and idler shafts  11 ,  19  only at front and rear ends thereof with corresponding front and rear bearings  23 F,  23 R such that the sprockets  15 ,  21  and shafts  11 ,  19  rotate unsupported between the front and rear bearings. To prevent bending of the shafts  11 ,  19  the cross-sectional area of at least the main portion  11 A,  19 A of the driven and idler shafts is increased to increase the bending resistance thereof. Alternately the entire length of the shafts can be increased as schematically illustrated in  FIG. 5 . 
     The method further comprises mounting a scraper device  35  such that an outer scraping projection  37  thereof extends between an inside surface of one of the front and rear walls  7  and the outer surface  33  of an adjacent sprocket  15 ,  21  such that an end edge of the outer scraping projection  37  is in proximity to the shaft  11 ,  19  carrying the sprocket. The side edges of the outer scraping projection  37  are in proximity to the inside surface of the wall  7  and the outer surface  33  of the adjacent sprocket. 
     An inner scraping projection  41  is also provided on the scraper device  35  separated from the outer scraping projection  37  by a gap  43  configured to allow the adjacent sprocket  15 ,  21  to rotate in the gap. An end edge of the inner scraping projection  41  is in proximity to the shaft carrying the adjacent sprocket and a side edge of the inner scraping projection  41  is in proximity to the inner surface  31  of the adjacent sprocket. 
     The apparatus and method of the present invention thus reduce wrapping of twine on the chain and slat conveyor of a bale processor. Time and effort needed to remove twine is reduced, and the risk of damage from wrapped twine is reduced as well. 
     The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all such suitable changes or modifications in structure or operation which may be resorted to are intended to fall within the scope of the claimed invention.