Abstract:
Rotary accelerating apparatus for a crop residue spreader of an agricultural combine, including blades mounted to a rotatable hub for rotation therewith, each of the blades having a surface oriented to face in the direction of rotation, the surface having opposite, spaced axial edges, and a mounting portion disposed intermediate the edges, and arms connected to and extending between the blades and the hub, each of the blades having first and second surface portions disposed primarily for contacting different flows of crop residue emanating from different locations for integrating, accelerating and discharging the flows for dispersal over an agricultural field, the mounting location of the blades, and the relative shapes and sizes of the portions thereof providing advantageous load distribution and transfer characteristics.

Description:
TECHNICAL FIELD 
     This invention relates generally to a crop residue spreader for an agricultural combine, and more particularly, to rotary crop accelerating apparatus for a spreader, the accelerating apparatus including blades which are supported advantageously for optimally distributing loads generated by contact with and acceleration of crop residue such as chaff and straw, and which blades are optimally shaped and located for receiving and accelerating flows of chaff and optionally straw for discharge from the spreader and distribution over an agricultural field. 
     BACKGROUND ART 
     Rotary crop residue spreaders for agricultural combines are well known in the art. Reference in this regard, Clarke U.S. Pat. No. 4,591,102, issued May 22, 1986, which discloses a representative chaff spreader for a combine harvester including rotary crop accelerating apparatus comprising fans having a plurality of radially extending blades, the fans each being rotatable for propelling crop residue outwardly from a housing partially containing the fan. Other known spreaders utilize a rotating disk supporting a plurality of radially extending blades or impellers on one surface thereof for engaging and propelling crop residue or other material in a radially outward direction. Reference in this regard, Scott et al. U.S. Pat. No. 4,892,504, issued Jan. 9, 1990 to Gehl Company. 
     An observed shortcoming, however, of both the known fan type accelerating apparatus and the known disk type accelerating apparatus, is that loads generated by the rotation of the fan blades and from contact with the crop residue are not ideally or optimally transferred to supporting structure such as a central hub or casting in the instance of the fan type apparatus, and to the supporting disk in the instance of the disk type apparatus, such that the blades will typically have a relatively narrow profile and the spreaders will have a less than optimal capacity, operability and durability. Still further, it is desired to provide a crop accelerating apparatus for a spreader which is better capable of handling different or mixed crop residue flows such as straw and chaff. Straw, for the present purposes, typically includes bean and grain stalks and stems, corn cobs, weeds, vines, and the like, is typically relatively heavy, and is delivered to the spreader from above. Chaff, which typically includes more intimately associated aspects of the bean, grain or other crop being harvested, is typically blown or otherwise delivered to the spreader from a more forward direction, comprises small constituent elements compared to the straw flow, and is typically less dense or voluminous compared to the straw flow. 
     Therefore, what is sought is rotary crop residue accelerating apparatus for a spreader of a agricultural combine which overcomes the shortcomings and provides the advantageous properties discussed above. 
     SUMMARY OF THE INVENTION 
     According to one preferred aspect of the present invention, rotary accelerating apparatus for a crop residue spreader of an agricultural combine which overcomes the shortcomings and provides the advantageous properties discussed above, is disclosed. The present rotary accelerating apparatus is particularly will adapted for receiving flows of chaff and straw from different directions and having different densities and other characteristics, and accelerating the flows and discharging them from the spreader together and relatively evenly over an agricultural field. The present apparatus includes a hub mountable on a rotatable member of the spreader, such as a shaft of a hydraulic, electric or other motor, for rotation therewith in a predetermined rotational direction about a rotational axis oriented generally horizontally or at a small acute angle to horizontal. The apparatus includes a plurality of blades disposed at angularly spaced locations around the rotational axis and extending radially outwardly from the axis and the hub. Each of the blades has a surface oriented to face in the rotational direction, the surface having a first axial edge and a second axial edge axially spaced from and opposite of the first axial edge. Each of the blades additionally includes a mounting portion disposed intermediate the first and second axial edges. The apparatus includes a plurality of arms connected to and extending radially outwardly from the hub at angularly spaced locations around the rotational axis and connected to the mounting portion of the blades, respectively, for supporting the blades for rotation with the hub about the axis. The surface of each of the blades includes a first surface portion extending from the first axial edge to about the mounting portion and having a predetermined first axial extent therebetween and a predetermined first radial extent relative to the rotational axis, and a second surface portion extending from about the mounting portion to the second axial edge having a predetermined second axial extent therebetween and a predetermined second radial extent, the first axial extent being substantially greater than the second axial extent and the first radial extent being substantially greater than the second radial extent, and wherein the first and second surface portions of the blade are positioned one relative to the other in relative to the rotational axis such that when the hub is mounted to the rotational member, the first surface portions of the blades will be located primarily in the path of the flow of chaff from the combine and the second surface portions will be located primarily in the path of the flow of straw from the combine such that more desirable load distribution and crop residue handling properties are achieved. For instance, centrifugal forces resulting from the rotation, and applied forces resulting from contact with the crop residue have been found to be better distributed and transferred to the arms, hub and rotatable members, resulting in improved durability. The profile of the blades also have been found to provide better integration of the different crop residue flows, such that there is less rejection of the chaff by the heavier, bulkier straw and less accumulation of the crop residue in the spreader. 
     According to a preferred aspect of the invention, each of the blades of the rotary accelerating apparatus has an axially extending radially outermost edge having a stepped or notched shape including a first edge portion extending along the first surface portion and a second edge portion extending along the second surface portion radially inwardly of the first edge portion, which configuration has been found to favorably affect the load distribution and integration of the crop residue flows, as well as the outflow of the accelerated crop residue. The larger diameter first surface portion of the blades protruding more forwardly facilitates the engagement, acceleration, and distribution of the chaff for a wide and uniform distribution thereof over the field. The smaller diameter more rearward second surface portion of the blades provides an improved means for engaging the straw and containing the straw in the upwardly open inlet region of the spreader, resulting in less rejection, and other adverse effects on the chaff flow along the more forward first surface portions of the blades. As a result, a consolidated advantageous effect on chaff and straw distribution over a field is achieved. As another advantage, the location of the mounting portion of the blades and connection to the supporting arms and hub is not constrained, and can be varied as required to achieve a desired force loading. 
     According to another preferred aspect of the invention, rotary accelerating apparatus for a crop residue spreader of an agricultural combine is disclosed, which includes a hub mountable on a rotatable member of the spreader for rotation therewith in a predetermined rotational direction about a rotational axis, the hub having a first axial end portion and a second axial end portion opposite of and axially spaced from the first axial end portion; a mounting bracket mounted to the first axial end portion of the hub and including a plurality of radially outwardly extending portions at spaced locations around the rotational axis or hub; a plurality of blades mounted to the radially outwardly extending portions, respectively, for rotation therewith about the rotational axis, each of the blades having a first axial edge portion located about axially coincident with the axial end portion of the hub and the radially outwardly extending portions, and a second axial edge portion opposite the first axial edge portion; and a disk mounted to at least some of the second axial edge portions of the blades and for rotation therewith for enclosing an adjacent axial end of spaces between adjacent ones of the blade. 
     A principle advantage of this embodiment is the support of the disk by the blades as opposed to the reverse, that is, the support of the blades by the disk, it having been found that loads resulting from the rotation and contact with the crop residue being more favorably distributed by the present arrangement. This arrangement also demonstrates the variability of the location of the attachment of the blades to the arms. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a fragmentary simplified side view of an agricultural combine including a crop residue spreader including crop residue accelerating apparatus according to the present invention; 
     FIG. 2 is an enlarged perspective view of the spreader of FIG. 1; 
     FIG. 3 is an enlarged side view of the accelerating apparatus of the spreader of FIG. 1; 
     FIG. 4 is a rear perspective view of the accelerating apparatus of FIG. 3; 
     FIG. 5 is a fragmentary sectional view of the spreader of FIG. 1, showing chaff and straw flows in relation to accelerating apparatus thereof; 
     FIG. 6 is a sectional view of the spreader of FIG. 1, illustrating rotation of accelerator apparatus thereof and acceleration of crop residue thereby; 
     FIG. 7 is a simplified fragmentary side view of an agricultural combine including another crop residue spreader including crop residue accelerating apparatus of the invention; 
     FIG. 8 is a perspective view of the spreader of FIG. 7; and 
     FIG. 9 is a perspective view of the accelerating apparatus of FIGS.  7  and  8 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, wherein preferred embodiments of the present invention are shown, in FIG. 1, a rear end  10  of a typical self-propelled agricultural combine  12  is shown, including a rotary crop residue spreader  14  including rotary crop residue accelerating apparatus  16  constructed and operable according to the teachings of the present invention. Briefly, combine  12  includes a threshing mechanism  18  which separates straw, including stalks, cobs, stems, weeds and other larger plant matter, from the harvested crop, and feeds that material to a rotating straw walker or beater mechanism  20  which carries or propels a flow  22  of the straw rearwardly, denoted by arrows A through an internal duct of combine  12  and against a deflector plate  24 , which helps deflect the flow  22  downwardly, denoted by arrows B, into spreader  14 . At the same time, cleaning apparatus  26  of combine  12  separates chaff, such as seed pods and husks, from the threshed grain, and directs or blows a flow of the chaff, denoted by arrows C, rearwardly into spreader  14 . 
     Referring also to FIG. 2, wherein only spreader  14  is shown, spreader  14  includes a housing  28  having a rear wall  30  and side walls  32  and  34 , defining and partially enclosing a pair of side-by-side spaces  36 , each including a crop residue accelerating apparatus  16  for rotation therein in a predetermined rotational direction, as denoted by arrows D. Housing  28  defines an upwardly and forwardly open inlet region  38  positioned to receive the generally downwardly extending flow of straw, denoted by arrows B, and a forwardly and upwardly open region  40  positioned for receiving the flow of chaff, denoted by arrows C, such that rotation of crop residue accelerating apparatus  16  in the rotational directions D will accelerate and discharge the flows through opposite sidewardly facing openings  42 , as denoted by arrows E. Each crop residue accelerating apparatus  16  is mounted on a rotational shaft  44  for rotation therewith, each shaft  44  extending through an opening in rear wall  30  and being drivingly connected to a motor  46 , which can be, for instance, an electric motor, fluid motor, or the like (FIG.  1 ), operable for rotating shaft  44  and crop residue accelerating apparatus  16  for accelerating and propelling or discharging the crop residue, as denoted by arrows E, a desired distance from spreader  14 . 
     Referring also to FIGS. 3 and 4, which show one of the crop residue accelerating apparatus  16  representative of the other apparatus  16 , each apparatus  16  includes a central hub  48  which mounts on shaft  44  for rotation therewith in the rotational direction D (FIG.  2 ), about a rotational axis  50  of shaft  44 . Hub  48  is preferably a tubular or hollow cylindrical or similar shape member including a first axial end portion  52 , a second axial end portion  54  axially spaced from and opposite axial end portion  52 , and an axial hole  56  at least partially through hub  48  for receiving shaft  54 . First axial end portion  52  preferably includes a radially outwardly extending annular flange  58  therearound, supported by a plurality of axially extending ribs  60  connected to flange  58  and hub  48  at angularly spaced locations therearound. A generally planar or flat blade support member  62 , preferably of unitary construction, is mounted to flange of first axial end portion  52  of hub  48  in a suitable manner such as by a plurality of bolts  64  which pass through holes in flange  58  and member  62 , and which are secured by nuts  66 , for rotation with hub  48  about rotational axis  50 . Member  62  preferably extends at least substantially around hub  48  and includes a plurality of arms  68  located at angularly spaced locations around axis  50  and extending radially outwardly relative to hub  48 . Each arm  68  preferably has a generally radially outwardly extending leading edge portion  70 , and a trailing edge portion  72  which is angularly related to leading edge portion  70 . Each leading edge portion  70  includes an elongate tab  74  oriented so as to have a surface facing the rotational direction. 
     A blade  76  is suitably mounted to each arm  68  so as to extend radially outwardly relative to hub  48 , preferably by a plurality of bolts  64  which pass through holes in tabs  74  and are secured by nuts  66 . Each blade  76  has a surface  78  oriented to face in the rotational direction (arrows D in FIG. 2) and including a first axial edge  80 , and a second axial edge  82  opposite edge  80 , edges  80  and  82  extending generally radially outwardly relative to rotational axis  50 , and each blade  76  including an intermediate or mounting portion  84  preferably located intermediate or in spaced relation between edges  80  and  82 . 
     Referring also to FIGS. 5 and 6, surface  78  of each blade  76  includes a first surface portion  86  extending from first axial edge  80  generally or about to mounting portion  84 , and a second surface portion  88  extending generally or about from mounting portion  84  to second axial edge  82 , first surface portion  86  being positioned generally or primarily in the path of the flow of chaff denoted by arrows C, and second surface portion  88  being positioned primarily in the path of the flow of straw, denoted by arrows B, such that the chaff and straw flows will be compressed by the rotation of blades  76  in the rotational direction, denoted by arrows D, and expelled or discharged at a greater velocity through sidewardly facing openings  42  of spreader  14  as denoted by arrows E, and distributed or spread over the agricultural field (not shown). Referring in particular to FIG. 5 first surface portion  86  of each blade  76  has an outward radial extent from rotational axis  50  to a radial outer edge portion  90  thereof which is substantially greater than the radial outward extent of second surface portion  88  to a radial outer edge portion  92  thereof, such that edge portions  90  and  92  together have a stepped or notched shape, and a central region  94  of first surface portion  86  will h)e offset radially outwardly of a central region  96  of second surface portion  88 . 
     The greater axial and radial outward extents of first surface portions  86  of blades  76  compared to second surface portions  88  thereof which provides the stepped or notched shape, and the different positioning of surface portions  86  and  88  relative to the straw and chaff flows as denoted by arrows B and C, respectively, is important and desirable as it provides a larger surface area for receiving and contacting the chaff and accelerating the chaff outwardly from spreader  14  in a relatively wide discharge pattern for distributing the chaff over a desirably large area of a field, and it provides a favorable resultant force loading on blades  76  and distribution or transfer of the force loads to arms  68 . More particularly in this latter regard, blades  76  are shaped and sized, and mounting portions  84  thereof are located, such that the flow of straw denoted by arrows B, which is relatively heavy, is directed more to and contacted by the stronger and better supported region of each blade  76  which primarily includes second surface portion  88  and mounting portion  84 , whereas the lighter flow of chaff denoted by arrows C is directed more to and contacted primarily by first surface portion  86  and mounting portion  84 . In this regard, it should be observed in FIG. 5 that arms  68  are generally aligned with about the center of the path of the flow of straw, and that central region  96  of second surface portion  88  of each blade  76  is backed up and supported by tab  74  of arm  68  so as to advantageously strengthen central region  96  and better transfer resulting loads thereon to arm  68 . It should also be noted that rear wall  30  of housing  28  includes an optional deflector plate  98  positioned for deflecting or guiding more rearwardly located portions of the flow of straw B forwardly toward blades  76 . 
     Second axial edges  82  of blades  76  is positioned in sufficiently close axially spaced relation to deflector plate  98  and rear wall  30  such that apparatus  16  is able to contact and carry the straw into space  36  such that the straw has less of a tendency to build up in the rear regions of spreader  14 . Still further, it should be noted that the extent of blade support members  62  between adjacent ones of blades  76  provides at least a partial barrier to keep longer plant material from wrapping around blades  76  and hub  48 . 
     Referring to FIGS. 7,  8  and  9 , in FIG. 7, rear end  10  of agricultural combine  12  is shown including a rotary crop residue spreader  100  including rotary crop accelerating apparatus  102  constructed and operable according to the teachings of the present invention, like parts of spreader  100 , accelerating apparatus  102  and spreader  14  and apparatus  16  being identified by like numbers. Spreader  100  differs from previously discussed spreader  14  in a number of important respects, including in that spreader  100  is oriented more horizontally compared to the more vertical orientation of spreader  14 , and includes a housing  104  comprising a partial upper wall  106  and opposing side walls  108  partially enclosing spaces  110  containing a pair of accelerating apparatus  102 . Each space  110  includes an upwardly open inlet region  112  through which a flow of chaff denoted by arrows C, and possibly some of a flow of straw D, is received, for acceleration by accelerating apparatus  102  and discharge through sidewardly facing discharge openings  114  for distribution over an agricultural field. 
     Referring more particularly to FIGS. 8 and 9, each crop residue accelerating apparatus  102  includes a central hub  48  which mounts on a shaft of a motor  46  (FIG. 7) which can be, for instance, an electric motor, fluid motor, or the like, operable for rotating the shaft and crop residue accelerating apparatus  102  in a rotational direction, denoted by arrows D (FIG. 8) for accelerating and propelling or discharging the crop residue a desired distance from spreader  100  as denoted by arrows E (FIG.  8 ). Hub  48 , again, is preferably a tubular or hollow cylindrical or similar shape member including a first axial end portion  52 , a second axial end portion  54  axially spaced from an opposite axial end portion  52 , and an axial hole (not shown) for receiving the shaft of motor  46 . Also as before, first axial end portion  52  of hub  48  includes a radially outwardly extending annular flange  58  therearound, supported by a plurality of axially extending ribs  60  connected to flange  58  and hub  48  at angularly spaced locations therearound. A generally planar or flat blade support member  62  is mounted to flange  58 , again in a suitable manner, such as by a plurality of bolts for a rotation with hub  48  about a rotational axis  50 . Member  62  preferably extends at least substantially around hub  48 , and includes a plurality of arms  68  located at angularly spaced locations around axis  50  and extending radially outwardly relative to hub  48 . Each arm  68  preferably has a generally radially outwardly extending leading edge portion  70 , and a trailing edge portion  72  which is angularly related to leading edge portion  70 . Each leading edge portion  70  includes an elongate tab  74  oriented so as to have a surface facing the rotational direction. Referring more particularly to FIG. 9, a blade  116  is mounted to each arm  68  so as to extend radially outwardly relative to hub  48 , preferably by a plurality of bolts  64  secured by nuts or the like. Each blade  116  has a surface  118  oriented to face in the rotational direction and including a first axial edge  120 , and a second axial edge  122  opposite edge  120 , edges  120  and  122  extending generally radially outwardly relative to rotational axis  50 , and edge  120  being oriented to extend also in the direction of rotation. A generally circular disk  124  is suitably mounted to second axial edges  122  of blades  116  in concentric relation therewith, by a plurality of bolts or the like, so as to be supported by blades  116  and enclose the axial end of spaces between adjacent ones of blades  116 . An important advantage of this construction is that because blades  116  are supported by blade support member  62  and in turn support disk  124 , instead of disk  124  supporting blades  116 , disk  124  can be of a lighter weight construction, if desired. This construction demonstrates the versatility of the present mounting arrangement utilizing blade support members  62  and central hub  48 , it being evident that this arrangement can be utilized to support blades at any desired axial location therealong. As another advantage of the mounting and support of blades  116  adjacent first axial edge  120  thereof, edges  120  of the blades can be oriented so as to extend at least partially into the direction of rotation of the accelerating apparatus, as shown here, to provide more aggressive gathering of chaff into the spreader. 
     It will be understood that changes in the details, materials, steps, and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates several preferred embodiments of the invention and methods of operation of the same; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown.