Apparatus for Macerating Plant Material

The present invention relates generally to apparatus for severely conditioning plant material and more particularly to improvements to apparatus for macerating plant material by first crushing the material and then impacting the crushed plant material one or more times. Apparatus of this general nature is also shown in copending U.S. patent application Ser. No. 08/884,277, filed Jun. 27, 1997.

During the process of producing and harvesting hay it is common to condition stalky plant material such as alfalfa, clover, or the like, by crimping the stems. This cracks the stems and thereby reduces the time cut plant material remains in the field by increasing the rate at which moisture escapes. U.S. Pat. No. 4,445,313, issued May 1, 1984 in the name of Thomas Elliott et al, discloses a machine illustrative of the general principle of conditioning by crimping. Another example of prior art showing conditioning by crimping is U.S. Pat. No. 4,862,681, issued Sep. 5, 1989 in the name of Gilbert W. Linde et al, which discloses conditioning rolls that crimp and also reciprocate relative to each other to enhance the conditioning.

In addition to crushing or crimping, it is also well known that plant drying can be further enhanced by subjecting the crushed plants to additional conditioning that causes the plant stems to be severely crushed and/or fiberized. This very severe conditioning is commonly referred to as maceration. The various levels of conditioning to which plant materials are subjected has a direct affect on the drying rate. Another benefit of severe conditioning, i.e., maceration, is that studies have shown that macerated hay enhances digestibility. Maceration is also carried out as a precursor to juice expression from herbage, where industrially valuable products, such as enzymes or nutritional substances are then extracted from the plant juice.

An example of prior art apparatus for macerating plant material, such as forage crops, is shown in U.S. Pat. No. 4,265,076, issued May 5, 1981 in the name of Gary W. Krutz, wherein a self propelled implement is disclosed. The crop material is macerated by a pair of opposing crushing rolls with differential peripheral speeds, after which it is conveyed to a press to form a mat that is discharged rearwardly onto the field over which the implement is being operated.

Another example of prior art apparatus for macerating plant material, also referred to as herbage, is shown in U.S. Pat. No. 5,152,127, issued on Oct. 2, 1992 in the name of Richard G. Koegel et al ( "'127 patent"). This patent, which provides an extensive explanation of background material relating to severe conditioning, discloses an implement for processing herbage, such as forage crop material, by cutting standing crop, feeding the cut crop material to a pair of crushing rollers to initially crack the stems of the plants, and subsequently impacting the crushed forage crop material to provide additional fiberization.

The copending application mentioned above is directed to the method and apparatus for reimpacting plant material after it has been impacted. Applicants know of no other prior art that relates to the reimpaction of plant material that has been impacted.

The present invention contemplates improvements to apparatus that impacts severely conditioned plant material one or more times.

An important object of the present invention is to provide simple and reliable apparatus for impacting plant material one or more times after it has been severely conditioned.

Another important object of the present invention is to provide simple and reliable apparatus having improved spreading attributes for varying the pattern of discharged plant material that has been reimpacted one or more times after it has been severely conditioned.

In pursuance of these and other important objects, the present invention contemplates harvesting apparatus adapted to traverse a field for cutting and processing plant material comprising in combination a forwardly extending header including a cutting assembly for cutting standing plant material, and a conveying assembly for conveying cut plant material rearwardly. The header apparatus further comprises crushing means for receiving the cut plant material from the header, crushing the plant material, and expelling it along a path in a generally rearward direction. Still further the apparatus comprises impaction means for impacting plant material received from the crushing means, and baffle means in the path of the outwardly directed impacted plant material for diverting it inwardly to be reimpacted by the impaction means. More particularly, the impaction means comprise a core member having a cylindrical outer surface, and a plurality of radially extending fins attached in an interrupted spaced array to the outer surface of the core member.

The present invention also contemplates apparatus for processing plant material comprising a first rotatable crushing roller having an outer generally cylindrical surface, a second rotatable crushing roller having an outer generally cylindrical surface positioned in close proximity to the outer surface of the first roller, the first and second rollers being adapted to rotate in opposite directions to crush plant material as it is passed between the rollers and urged downstream under conditions where the rollers are rotating. A rotatable impact rotor having a plurality of outwardly extending projections is mounted to rotate about a generally transverse axis downstream from and generally aligned with the first and second rotatable crushing rollers. The impact rotor is in the path of crushed plant material that has passed between the rollers, whereupon said crushed material is impacted by the outwardly extending projections to macerate the crushed plant material. Baffle means are mounted outwardly of the rotor to divert the macerated plant material back into the impact rotor for reimpaction of macerated plant material by the outwardly extending projections of the impact rotor. The baffle means comprise a hood having an inwardly facing surface mounted above the impact rotor. More particularly, the invention contemplates an auxiliary hood adjustably mounted on the hood to vary the exit trajectory of the reimpacted plant material.

The foregoing and other objects, features and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description which follows, in conjunction with the accompanying sheets of drawings wherein one principal embodiment of the invention is illustrated by way of example, along with other alternative embodiments. It is to be expressly understood, however, that the drawings are for illustrative purposes and are not to be construed as defining the limits of the invention.

FIG. 1 is a diagrammatical perspective view of self propelled harvesting apparatus in which the improvements of the present invention are incorporated.

FIG. 2 is an elevational view illustrating in further detail key elements of the present invention.

FIG. 2A is a view taken in the direction of arrows 2A--2A in FIG. 2.

FIG. 2B is a view taken in the direction of arrows 2B--2B in FIG. 2A.

FIG. 3 is a partial diagrammatical elevational view similar to FIG. 2 showing key elements of another embodiment of apparatus in which the improved rotor of the present invention is incorporated.

FIG. 4 is a partial diagrammatical elevational view also similar to FIG. 2 showing key elements of yet another embodiment of apparatus in which the improved rotor of the present invention is incorporated.

Referring now to the drawings for a more detailed description of the present invention, FIG. 1 diagrammatically shows a self propelled implement, generally designated by reference numeral 10, having a forwardly extending header 11 suspended from a frame in a conventional manner. The header includes a forwardly positioned transverse cutterbar 12 disposed in close proximity to the ground to sever standing plant material, a reel 13 for engaging the severed plant material and conveying it rearwardly over a floor 14, and a transverse auger 15 that consolidates the rearwardly conveyed plant material and discharges it through an opening (not shown) in a wall 16 extending upwardly from floor 14. The structure and function of header 11 is well known in the art, an example of which is shown and described in U.S. Pat. No. 5,327,709, issued Jul. 12, 1994 in the name of Bryant Webb, hereby incorporated by reference. The prior art elements of header 11 are depicted in a cut-away fashion to facilitate understanding.

In the embodiment depicted in FIG. 1 and shown in further detail in FIG. 2, crushing rolls 17, 18 are rotatably mounted on header 11 behind wall 16 in general transverse alignment with auger 15. The rotational direction of crushing rolls 17, 18 is illustrated by directional arrows a and b in FIG. 2. Crushing rolls 17, 18 are journalled in bearing assemblies mounted on sides walls 20, 21 of header 11 and driven by conventional means, such as chains, belts, gears, hydraulics, or a combination thereof. To accommodate varying thicknesses of plant material being crushed, rolls 17, 18 can be spaced and/or spring loaded toward each other in a conventional manner. The outer surfaces of crushing rolls 17, 18 are aggressive to improve feeding characteristics.

As depicted in FIG. 1, side wall 21 is shown in phantom to illustrate its position and thereby provide an unobstructed view of the elements of harvester 10, some of which elements are cutaway, as noted above. Cross beam member 22, which provides structural support and strength to header 11, extends between sidewalls 20, 21. Rear wall 16, mounted to cross beam member 22, extends from side to side between auger 15 and crushing rolls 17, 18, and is provided with the discharge opening mentioned above for appropriate unimpeded ingress of material to crushing rolls 17, 18.

Impact rotor 23, also mounted on header 11, is similarly journalled in opposing bearing assemblies mounted on side walls 20, 21 adjacent crushing rolls 17, 18. Conventional drive means rotate impact rotor 23 in the direction of arrow c, i.e., in a clockwise direction when viewed from the right side of the apparatus shown in FIGS. 1 and 2, about transverse axis 24. The position of axis 24 is adjustable vertically and horizontally to modify the spacing and vertical relationship between crushing rolls 17, 18, and impact rotor 23.

More specifically, impact rotor 23 comprises a plurality of outwardly extending rigid fins 25 (see FIGS. 2A and 2B) equidistantly spaced along the outer surface of a cylindrical core 26. Each fin 25 includes a radially extending transverse strut 27 welded to core 26. An impact element 28 is affixed by conventional means to each strut 27, which elements also extend in a generally radial direction and have a rounded leading edge. Referring to FIGS. 2A and 2B, in the preferred embodiment impact elements 28 are removably affixed to struts 27, which are affixed to core 26 in a staggered and segmented manner, along a general spiral path. Among others things, this segmented array provides for economical routine servicing, as well as field repair of rotor 23. Replacement of separate segments due to wear or damage greatly reduces the time, effort and expense involved. Further, by staggering the segments from row to row along a spiral path, the adjacent staggered segments engage the crop in a sequential manner similar to a continuous spiral element. This distributes loading which gives more uniform torque characteristics without the disadvantage of using a costly spiral element that spans the entire width.

A deflector hood assembly 30, mounted between side walls 20, 21, comprises an inwardly facing arcuate surface 31, 31' to which a plurality of guide elements 32, 33, 34 are secured. More specifically, guide element 32 is triangularly shaped in cross section with a flat impact surface 35 in the downstream path of plant material that has been crushed by rolls 17, 18, impacted by rotor 23, and then impelled in a general upward direction. Surface 35 extends from side to side with its rear portion terminating in the vicinity of the cylindrical path of the tips of impact elements 28. Guide elements 33, 34, similar in configuration to each other, are angularly shaped and selectively attached along surface 31, 31'. Rearmost element 34 is radially adjustable relative to the cylindrical path of the tips of impact elements 28 by virtue of moveable segment 36 of inwardly facing wall 31, the innermost position of which is shown in phantom outline.

An auxiliary hood 37 comprises a flat inwardly facing deflection element 38 pivotally mounted to deflector hood assembly 30 at pivot assembly 40 for adjustment between an inner position 41 shown in phantom outline, and an outer position shown in solid lines. Deflection element 38 includes generally triangular ribs 29 secured to pivot assembly 40 via wing nuts in slots 39 that register with like slots in two or more vertically disposed flanges 42. The surface of deflector element 38 is continuous from side to side with its forward edge contiguous with the rearward edge of inwardly facing surface 31'. By varying the position of auxiliary hood 37 the discharge path of processed plant material can be selectively positioned on a conveyor 43, generally shown in FIG. 1 and partly shown in FIG. 2. Conveyor 43 is operatively mounted downstream from impact rotor 23 for conveying processed crop rearwardly in a uniform manner regardless of crop quantity and density. By selectively positioning the surface of deflection element 38 the apparatus can be preadjusted to maximize throughput, based on anticipated type of plant material and crop conditions in the field being harvested.

Intermediate frame assembly 44 is disposed between sidewalls 20, 21 to provide structural integrity via intermediate brackets 45 (one shown) affixed between deflector hood 30 and assembly 43 by bolts 46, or other suitable holding means. Attached to frame assembly 43 is scrapper 47 with an edge in operative relationship with the surface of crushing roll 17 for functioning in a well known manner.

In FIG. 3, an alternative embodiment is illustrated wherein similar crushing rolls are used in conjunction with impact rotor 23 and a deflector hood assembly 48, pivotally adjustable about transverse axis 50. Arcuate guide surfaces 51, 52 are affixed to the inner surface 53 of hood assembly 48 via intermediate retaining elements 54, 55. Plant material is engaged by surfaces 51, 52 in a manner similar to guide elements 32, 33 of the FIG. 2 embodiment, i.e., as it is being conveyed along a generally circumferential path after initial impaction. Guide surface 51 redirects the material back against impact elements 28 of impact rotor 23 whereupon reimpaction takes place that in turn redirects the material away from impact rotor 23 and into guide surface 52, which again redirects the material back toward impact elements 28 for another reimpaction to further macerate the plant material prior to being discharged from hood assembly 48 onto a rearwardly transporting conveyor 43 of the type depicted in FIGS. 1 and 2. In this embodiment the discharge path of the macerated material can be varied by pivoting hood assembly 48 about transverse axis 50, which varies the relationship of guide surfaces 51, 52 with respect to the path of the tips of fins 25.

In FIG. 4, another alternative embodiment is illustrated wherein similar crushing rolls are used in conjunction with impact rotor 23 and a deflector hood assembly 56, pivotally adjustable about transverse axis 57. In a manner similar to the FIG. 2 embodiment, guide elements 58, 60 are affixed to the inner surface of deflector hood 56 to engage plant material as it is being conveyed along its generally circumferential path. Guide element 58 is angularly shaped with a transverse flange 61 for receiving a plurality of bolts 62 (one shown) for securing it to the inner surface 63 of hood 56. In a like manner guide element 60 is angularly shaped and includes inwardly turned flanges 64, 65 for securement to the hood. Leading surface 66 of element 58 redirects material back against impact elements 28 whereupon reimpaction takes place that in turn redirects the material away from impact rotor 23 and into transverse leading surface 67 of element 60, which in turn again redirects the material against impact elements 28 of rotor 23 for additional reimpaction to further macerate the plant material prior to being discharged from the hood onto a rearwardly transporting conveyor. In this embodiment, as in the FIG. 3 embodiment, the rearward discharge path of the macerated plant material can be varied by pivoting hood assembly 56 about transverse axis 57.

In operation, each of the above discussed configurations provides for crushing, impaction and reimpaction of plant material being processed. In each embodiment the impact rotor impacts the crushed material as it rotates upwardly, but regardless of direction of rotation all configurations accomplish the unique function of reimpaction of plant material, e.g., forage crop material, that has been crushed and impacted. The invention contemplates in general an impact rotor mounted downstream from a crushing assembly and adjacent a hood. Material crushed by the crushing assembly is thrust against the fins of the impact rotor, which is rotating at a relatively high rate of speed. For example, with the crushing rolls rotating at 800 RPM, a typical speed for the impact rotor would be in a range of 1000 RPM to 3000 RPM, depending on the type and maturity of the crop being processed. The crushed material is macerated by the impact of the fins and deflected one or more times back to an area adjacent the rotor where it engages a deflector which guides it along a generally circumferential path to a conveyor assembly, conveyed rearwardly, and subsequently deposited on the surface of the field as depicted in FIG. 1. A pressing assembly (not shown) can also be employed rearwardly of the deflector hood, in which case the material is pressed into a mat prior to being deposited on the field.

Of the many implicit and explicit advantages of the present invention one of the most important is the provision of apparatus that allows the extent of maceration of plant material to be selected within a wide range. This extends the application of the maceration apparatus from moderate conditioning for accelerated field drying to very severe maceration where it is desired to express juice from the herbage as a source of value added products. Examples of potentially significant valuable value added products are livestock and/or food-grade protein concentrates, pigmenting agents for the poultry industry, and industrially valuable enzymes. If While preferred structure in which the principles of the present invention are shown and described in the embodiments above, it is to be understood that the invention is not limited to such preferred structure, but that, in fact, widely different means of varying scope and configuration may be employed in the practice of the invention. Further, while the unique apparatus and method of the present invention is discussed above, in some instances, as being adaptable to handle forage crop material, it is not intended that it be limited to that type of herbage.