Abstract:
The grain holding bin of a combine harvester can be rapidly unloaded either on-the-go or at a standstill by an inclined unloading conveyor having its intake end at a low point in the bin adjacent the far side of the bin. The unloading conveyor extends gradually upwardly and outwardly in a straight line from its intake end to a point above and beyond the opposite side of the bin to provide a straight, unrestricted run for grain being unloaded without twists, turns and significant breaks in auger flighting. The outer end of the unloading conveyor can be pivoted back into a rearwardly extending transport position about a simple generally upright pivot hinge. The driving connection between inner and outer portions of the interior auger of the unloading conveyor is automatically re-established as the outer section of the unloading conveyor is returned to its unloading position, notwithstanding the fact that the unsupported inner end of the outer auger section drops slightly out of concentricity with its surrounding tubular housing when the outer conveyor section is in its transport position.

Description:
TECHNICAL FIELD  
       [0001]     This invention relates to combine harvesters and, more particularly, to the grain bin unloading systems of such machines.  
       BACKGROUND AND SUMMARY  
       [0002]     It is well known in the art to provide unloading conveyors for the grain holding bins of combine harvesters so as to permit such machines to be unloaded either on-the-go or at a standstill into trucks or other receptacles. As combine harvesters get larger and larger, however, the holding capacity of their bins likewise increases. In order to retain reasonable unload time, the unload rate must increase to keep pace with the increased storage capacity.  
         [0003]     One complicating factor is that most existing combine bin unload systems are of the turret or swivel type which permits an outer portion of the unloading conveyor to be rotated or swung between unloading and transport positions. In such systems, there is an energy loss at the turret or swivel elbow due to the significant gap in auger flights necessitated by abrupt changes in auger directions. This results in restricted flow and increased power requirements, limiting the unloading rate.  
         [0004]     The present invention provides a way of overcoming the drawbacks in conventional systems to achieve increased unloading rates while still permitting the unloading conveyor to be folded out of its unloading position into a compacted position for transport. The invention also provides a way of automatically re-establishing the drive connection between sections of the foldable unloading auger as the out-of-alignment, folded section of the auger is returned from its transport position to its unloading position. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  is a side elevational view of a combine harvester incorporating the principles of the present invention and showing the outer section of the unloading conveyor in its folded back, transport position;  
         [0006]      FIG. 2  is a fragmentary, left, front, top isometric view of the grain bin of the harvester with the outer section of the unloading conveyor in its transport position;  
         [0007]      FIG. 3  is a fragmentary, left, front, top isometric view of the grain bin similar to  FIG. 2  but showing the outer section of the unloading conveyor in its unloading position;  
         [0008]      FIG. 4  is a fragmentary, enlarged, left, rear top view of the unloading bin with the outer section of the unloading conveyor in its unloading position and with the hopper-like bin extensions removed to reveal details of construction;  
         [0009]      FIG. 5  is a fragmentary top plan view of the grain bin showing the outer conveyor section in its unloading position and the bin extensions removed for clarity;  
         [0010]      FIG. 6  is a transverse cross-sectional view through the grain bin taken generally along the fore-and-aft line  6 - 6  of  FIG. 5 ;  
         [0011]      FIG. 7  is a transverse cross-sectional view of the grain bin with the outer section of the unloading conveyor in its unloading position and taken substantially along line  7 - 7  of  FIG. 5 ;  
         [0012]      FIG. 8  is a transverse cross-sectional view through the grain bin similar to  FIG. 7  but taken along line  8 - 8  of  FIG. 5 ;  
         [0013]      FIG. 9  is an enlarged, fragmentary isometric view of the unloading conveyor at its hinge point with the outer section thereof folded back into its transport position and illustrating the releasable drive coupling between inter-engaging ends of auger sections of the unloading conveyor;  
         [0014]      FIG. 10  is an enlarged, fragmentary isometric view of the unloading conveyor at its hinge point illustrating the outer conveyor section in its unloading position;  
         [0015]      FIG. 11  is a fragmentary, exploded isometric view of the unloading conveyor with the outer section thereof in its transport position;  
         [0016]      FIG. 12  is an enlarged, fragmentary top plan view of the unloading conveyor with the outer section thereof in its transport position and portions broken away to reveal internal details of construction;  
         [0017]      FIG. 13  is an enlarged, fragmentary top plan view of the unloading conveyor as the outer section thereof is swung toward its unloading position and the drive coupling between the two auger sections is in the process of being re-established; and  
         [0018]      FIG. 14  is a fragmentary top plan view of the unloading conveyor similar to  FIG. 13  but showing the outer section of the conveyor fully swung to its unloading position wherein the driving relationship between auger sections of the unloading conveyor is re-established. 
     
    
     DETAILED DESCRIPTION  
       [0019]     The present invention is susceptible of embodiment in many different forms. While the drawings illustrate and the specification describes certain preferred embodiments of the invention, it is to be understood that such disclosure is by way of example only. There is no intent to limit the principles of the present invention to the particular disclosed embodiments. References hereinafter made to certain directions, such as, for example, “front”, “rear”, “left” and “right”, are made as viewed from the rear of the harvester looking forwardly.  
         [0020]     The combine harvester  10  in  FIG. 1  has a grain holding bin  12  provided with downwardly converging, hopper-like extensions  14  that provide extra holding capacity for bin  12 . Grain that has been threshed, separated and cleaned by internal mechanism (not shown) of the harvester  10  is elevated and temporarily stored in bin  12  until unloaded either on-the-go or at a standstill into a selected receptacle. On-the-go unloading is directed into a receptable that travels alongside harvester  10  while harvesting operations continue to be carried out. An unloading conveyor broadly denoted by the numeral  16  is utilized for this purpose and includes an outer section  18  that is shown folded back into its transport position in  FIG. 1 .  
         [0021]     With particular reference to  FIGS. 2-8 , it will be seen that in the particular illustrated embodiment bin  12  is open at the top and has a front  20 , a rear  22 , a left side  24 , and a right side  26 . A window  28  in front  20  permits the operator seated in the cab  30  ( FIG. 1 ) to observe the condition of bin  12 .  
         [0022]     Bin  12  has a transverse auger trough  32  in the lower region thereof extending from left side  24  toward right side  26  and terminating a short distance inboard of the latter. A cross auger  34  is disposed within trough  32  and is rotated in such a direction as to feed grain toward right side  26 . Input power for driving cross auger  34  is supplied by a sprocket  36  on the left end of auger  34  which is entrained by a drive chain  38  looped around a smaller sprocket  40  on a jack shaft  42  having a double sheave  44  at its opposite end. Sheave  44  is wrapped by endless belts (not shown) that are operably coupled with a source of driving power from the engine of the harvester  10 . As illustrated particularly in  FIG. 5 , cross auger  34  has an adjustable partial cover  45  along the length thereof that leaves cross auger  34  partially exposed at the top for receiving grain through an elongated, adjustable width opening  47 .  
         [0023]     Bin  12  is provided with a number of inclined surfaces that encourage grain to gravitate downwardly into trough  32  to be acted upon by cross auger  34 . In this regard a rear floor  46  slopes downwardly and forwardly from rear side  22  adjacent the upper extremity thereof to a point just below trough  32  of cross auger  34 . Similarly, a front floor  48 , considerably shorter in length than rear floor  46 , extends downwardly and rearwardly from a point just below window  28  to a rearmost point at the forward extremity of trough  32 . Left side  24  has an uppermost, downwardly and inwardly inclined panel  50  extending from rear side  22  to front side  20 . Panel  50  terminates a short distance inwardly from the upper extremity of left side  24 . Right side  26  has an upright sidewall  52  without sloping portions, while left side  24  likewise has an upright sidewall  54  disposed below sloping panel  50  and recessed inwardly with respect to the outermost extremity of panel  50 . As illustrated only in  FIGS. 2 and 3 , a bin fill auger  56  (removed from the other figures for clarity) is provided within bin  12  for delivering clean grain from lower regions of the harvester  10  up into bin  12  to fill the latter.  
         [0024]     In a preferred form of the invention, unloading conveyor  16  comprises a hinging auger assembly having an inner portion disposed within bin  12  and an outer portion disposed outside of bin  12 . The auger assembly as a whole includes a two-part unloading auger  56  housed within a surrounding, hinged auger tube  58 . A downturned discharge spout  60  is provided at the outermost end of tube  58 . At the lower, intake end of unloading conveyor  16 , auger tube  58  terminates short of the proximal end of auger  56  so as to expose an intake portion  56   a  of auger  56  as illustrated particularly in  FIGS. 4, 5  and  8 . A sump  62  at the intersection of inclined rear floor  46  and cross auger trough  32  generally adjacent right side  26  presents a low point within bin  12  that receives the intake end  56   a  of auger  56 . Sump  62  is disposed immediately beside the delivery end of cross auger  34  in open communication therewith for receiving grain from cross auger  34 .  
         [0025]     As illustrated in  FIG. 7 , sump  62  is defined in part by a downwardly and inwardly inclined wall  64  serving as an extension of sidewall  52  in that area. A stub shaft  66  of auger  56  projects through sump wall  64  and carries a sprocket  68  that is drivingly connected by a chain  69  with a sprocket  70  drivingly coupled with the outer end of cross auger  34  as illustrated in  FIG. 8 .  
         [0026]     The two-part unloading conveyor  16  includes foldable outer conveyor section  18  as previously described, as well as a fixed inner conveyor section  72 . Inner conveyor section  72  includes an inner section  74  of auger tube  58 , as well as an inner section  76  of auger  56 . Similarly, outer conveyor section  18  includes an outer section  78  of auger tube  58  and an outer section  80  of auger  56 . Inner and outer auger sections  76 ,  80  are operably interconnected by a releasable drive coupling  82 , the details of which will subsequently be described.  
         [0027]     Outer conveyor section  18  is rendered foldable relative to inner conveyor section  72  by a generally upright, but slightly inwardly and rearwardly inclined pivot hinge  84 . Hinge  84  thus allows outer conveyor section  18  to be swung (folded) between an unloading position in which it is axially aligned with inner conveyor section  72  as illustrated in  FIGS. 3, 4 ,  5  and  7 , for example, and a transport position wherein outer section  18  extends transversely of inner section  72  and is disposed in a folded-back orientation as illustrated, for example, in  FIGS. 1 and 2 . A double-acting hydraulic cylinder  86  is operably coupled between left side  24  and outer conveyor section  18  for effecting such swinging motion of outer section  18  between its unloading and transport positions and for retaining outer section  18  in such positions. A door  88  is swingably attached to left side  24  in front of outer conveyor section  18  and is operated by a link  90  coupled with outer conveyor section  18  for swinging between an open position as illustrated, for example in  FIGS. 3 and 4  when outer section  18  is in its unloading position, and a closed position as illustrated in  FIGS. 1 and 2  when outer section  18  is in its transport position so as to visually cover the otherwise exposed open end of inner conveyor section  72 . A safety interlock system (not shown) may be provided that is responsive to the position of outer conveyor section  18  so as to permit unloading auger  56  to be activated only when outer conveyor section  18  is in its unloading position.  
         [0028]      FIGS. 9 and 10  are enlarged views of the hinge area of the unloading conveyor  16  showing the outer conveyor section  18  in its transport and unloading positions respectively. As illustrated particularly in those views, a first hinge plate  92  is rigidly affixed to left side  24  of bin  12  and fixedly receives the outer end of inner tube section  74 . A central, generally upright cylinder  94  of pivot hinge  84  is fixedly secured to plate  92 , while a pair of upper and lower, shorter hinge cylinders  96  and  98  are fixedly secured to another hinge plate  100  on the proximal end of outer tube section  84 . A hinge pin  102  is received by the aligned cylinders  94 ,  96  and  98  to maintain such cylinders in pivoting relationship with one another. A pair of internal bushings (not shown) within intermediate cylinder  94  receive hinge pin  102  to facilitate rotation of pin  102  with upper and lower cylinders  96 ,  98  during opening and closing of outer conveyor section  18 . A sealing ring  106  on the interior face of plate  100  ( FIG. 9 ) is slightly larger in diameter than the annular end  104  of inner tube section  74  that projects slightly beyond the interior face of plate  92  such that, when plates  92  and  100  are face-to-face when outer conveyor section  18  is closed as in  FIG. 10 , ring  106  and tube end  104  cooperate to form a labyrinth seal that prevents the escape of grain at the hinge point of the unloading conveyor  16 .  
         [0029]     With reference also now to  FIGS. 11-14 , the details of construction of drive coupling  82  will be explained. Dealing first with inner conveyor section  72 , it will be seen that inner auger section  76  has an axially extending bore  108  in the outer end of its tubular shaft  110  which receives a drive shaft  112  that is held in place by a pair of transverse bolts  114 . Drive shaft  112  projects outwardly beyond the end of auger shaft  110  and is journaled for rotation by bearings  116  that are supported by a hanger bracket  118  fixed to the inside surface of inner tube section  74  of inner conveyor section  72 . Hanger bracket  118  thus supports the outer end of inner auger section  76  concentrically within inner tube section  74  so that flighting  120  on auger shaft  110  does not engage the interior surface of inner tube section  74 . The opposite end of auger shaft  110  is rotatably supported by bearings associated with the inclined sump wall  64 .  
         [0030]     The outer end of drive shaft  112  is splined so as to matingly receive an internally splined, generally spherical drive component  122  of drive coupling  82  (hereinafter referred to as “drive ball”  122 ). Drive ball  122  is secured to drive shaft  112  by suitable means such as an axially extending screw  124  ( FIGS. 12, 13  and  14 ). The annular end face  126  of drive ball  122  is provided with drive structure in the form of a set of undercut teeth (hardened for wear resistance) that matingly engage with drive structure in the form of undercut teeth on the other major component of drive coupling  82  on outer conveyor section  18  as hereinafter described. Although drive ball  122  is herein described as being spherical, it will be seen that such component may take other shapes, such as for example, parabolic, within the concepts of the present invention. It is important, in any event, that drive ball  122  be provided with a suitably arcuate outer surface that can serve as piloting means during re-engagement of the drive between inner and outer auger sections as hereinafter explained.  
         [0031]     Outer auger section  80  is rotatably supported at its outer end in a concentric relationship by means not illustrated, but the inner end of outer auger section  80  is not supported concentrically unless outer section  80  is engaged drivingly with inner auger section  76 . Thus, when outer conveyor section  18  is in its transport position, the inner end of outer auger section  80  lies against the interior surface of outer tube section  78 . Flighting  128  around the outside of tubular auger shaft  130  bears against the interior surface of outer tube section  78  at such time. It is to be noted that flighting  128  extends for a distance beyond the inner end of outer auger section  80  so as to leave only a small discontinuity in flighting along the entire length of auger  56  (in the area of hanger bracket  118 ) when outer conveyor section  18  is in its unloading position.  
         [0032]     The inner end of outer auger shaft  130  is configured to present a socket  132  having an outturned lip  134 . Socket  132  defines an interior chamber  136  that slidably and axially receives a second drive component  138  of drive coupling  82 . Drive component  138  is recessed within chamber  136  and is retained against escape therefrom by a snap ring  140  installed in the inside wall surfaces of socket  132 . An annular dust seal  141  surrounds drive component  138  generally outboard of snap ring  140 .  
         [0033]     Drive component  138  is generally annular in configuration and is internally, axially splined so as to be axially received upon the splined outer end of a drive shaft  142  within a bore  144  ( FIGS. 12, 13  and  14 ) within the end of outer auger shaft  130 . A set of compression springs  146  are contained within counterbores in socket  132  and bear against the inboard face of drive component  138  so as to yieldably bias drive component  138  outwardly toward and against snap ring  140 . Drive shaft  142  is fixedly secured to auger tube  130  by transverse bolts  150 .  
         [0034]     The annular outermost face  152  of drive component  138  has driving structure in the form of a series of undercut teeth thereon configured to complementally engage with the teeth of face of  126  of drive ball  122  when outer conveyor section  18  is in its unloading position as illustrated in  FIG. 14 . When drive components  122  and  138  are operably engaged as illustrated in  FIG. 14 , drive component  138  is preferably slightly depressed away from snap ring  140  against the force of compression springs  146 .  
         [0035]     Drive coupling  82  also includes an annular, hardened guide  154  disposed at the open outer end of socket  132  in concentric relationship therewith. A flange  156  of guide  154  overlies and is secured to lip  134  by suitable fasteners not shown, while an annular wall  158  of guide  154  projects for a distance into the mouth of socket  136  and bears against the internal annular surface thereof. Guide  154  has an annular bevel  160  at the intersection of flange  156  and wall  158 .  
         [0000]     Operation  
         [0036]     When the unloading conveyor  16  is in its unloading position, grain entering the intake end of conveyor  16  at the intake portion of  56   a  of auger  56  travels up a gentle slope and in a straight line from a low point near right side  26  to the discharge spout  60  without encountering elbows, bends, corners, vertical climbs, or significant breaks in auger flighting. Consequently, grain can be unloaded at a significantly higher rate of speed than conventional turret and swivel type unloaders wherein significant speed and power losses occur at various points in the unloading path of travel. In one preferred embodiment, the rise of the unloading conveyor  16  is approximately thirteen degrees.  
         [0037]     It will be appreciated that during unloading operations, grain in bin  12  is directed to the sump  62  where it encounters the exposed intake portion  56   a  of auger  56 . Some of the grain gravitates naturally toward sump  62  as a result of the various inclined, interior surfaces of bin  12  such as rear floor  46 , front floor  48  and panel  50 . In addition, cross auger  34  moves grain that has entered trough  32  through opening  47  toward the right end of trough  32  where it crosses into sump  62  and is picked up by the intake end of auger  56 . This action results in a highly efficient and rapid unloading of bin  12 .  
         [0038]     During unloading operations, outer unloading section  18  is held in its unloading position by hydraulic cylinder  86 . The components of drive coupling  82  are maintained in driving engagement with one another as illustrated in  FIG. 14 . As cylinder  86  is retracted to swing outer conveyor section  18  back to its transport position about pivot hinge  84 , drive components  122  and  138  of drive coupling  82  become disconnected as illustrated in  FIG. 12 . During such cracking or opening of unloading conveyor  16 , any leftover grain in the vicinity of drive coupling  82  can gravitate into a catch basin  162  ( FIG. 8 ) which opens downwardly into the cross auger trough  32  for handling by cross auger  34  when unloading operations are next commenced. Once drive components  122  and  138  have been disconnected from one another, the inboard end of outer auger section  80  drops slightly within outer tube section  78  until flighting  128  comes to rest on the interior surface of outer tube section  78 . Such drop of the inboard end of inner auger section  76  is on the order of ¼ inch in one preferred embodiment.  
         [0039]     Consequently, when swing cylinder  86  is thereafter extended to return outer conveyor section  18  to its unloading position, the inboard end of outer auger section  80  will be out of alignment with inner auger section  76 , which has been maintained in its concentric relationship within tube  58  by the hanger bracket  118  and its bearing supports at sump wall  64 . Such mismatch is overcome, however, by the interaction of the arcuate outer cam surface of drive ball  122  and guide  154  as outer conveyor section approaches its unloading position.  FIG. 13  generally illustrates this action, although the misalignment of the inboard end of outer auger section  80  is not noticeable due to the overhead viewing angle in  FIG. 13 . As drive ball  122  enters guide  154 , the inboard end of outer auger section  80  is cammed into axial alignment until such alignment is again achieved as illustrated in  FIG. 14 .  
         [0040]     As noted earlier, it is desirable for the dimensional relationships of inner and outer auger sections  76 ,  80  to be such that springs  146  are slightly compressed when the teeth on face  126  of drive ball  122  are fully meshed with the teeth on face  152  of drive component  138 . In the event that such teeth are not perfectly enmeshed by the time unloading auger  16  is turned on, such meshing relationship will be quickly established when drive ball  122  rotates slightly relative to drive component  138 . Once the proper rotative relationship is achieved, springs  146  snap drive component  138  outwardly into driving relationship with drive ball  122 .  
         [0041]     The inventor(s) hereby state(s) his/their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of his/their invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims.