Abstract:
A compost windrow turning machine disintegrates an existing windrow of compost material, conveys the disintegrated material rearwardly, aerates the rearwardly conveyed material with a positive displacement of air into the rearwardly conveyed compost material, and re-forms a new windrow of remixed and aerated compost material rearwardly of the machine in line with the original windrow. The disintegration of the original compost windrow is accomplished with a rotor having segmented teeth arranged in a spiral to shred the original compost material and convey the disintegrated material to a central chain and slat conveyor positioned behind the rotor. A positive displacement of air is injected into the compost material on the central conveyor by a pair of laterally disposed fans mounting in conduits angled inwardly toward the central conveyor. The discharge of material off the central conveyor is passed through a set of windrow-forming shields to create a new windrow.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to a machine for turning windrows of compost material, and, more particularly, to an apparatus that injects air into the compost windrow as the compost is being conveyed through the machine. 
       BACKGROUND OF THE INVENTION 
       [0002]    Composting is well recognized as an environmentally sound and economical means of recycling a variety of organic, biodegradable materials. Various composting technologies are available, including static pile composting, windrow composting, aerated-windrow composting, and in-vessel composting employing, for example, circular reactors, horizontal agitated bay or bin reactors and vertical reactors. 
         [0003]    Biodegradable materials can be composted on a mass production basis by arranging the biodegradable material being composted into long stacks, or windrows that are placed within shelters to keep moisture off of the windrows. Generally, the windrows of compost can have a width of ten to fifteen feet, a height of six to eight feet and a length of hundreds of feet with the top surface being generally rounded. Periodically, at least twice each week, it is necessary to turn, or more accurately re-mix, the windrow of biodegradable material being turned into compost. This re-mixing of the windrow serves to incorporate air into the windrow to facilitate the aerobic process that is taking place to convert the biodegradable materials into compost. In addition, the re-mixing of the compost materials serves to redistribute the microbiological agents, and break up the partially decomposed materials into smaller particles to further facilitate the aerobic process that biologically degrades the material into compost. Improved aeration of the windrow of compost material will hasten the aerobic process. 
         [0004]    Known compost turning machines engage the long windrow of compost material and elevate the material before reforming the windrow usually within the line of the windrow being remixed. Examples of such machines can be found in U.S. Pat. No. 5,387,036, issued to Daniel Hagen, et al on Feb. 7, 1995; in U.S. Pat. No. 5,395,417, issued to Thomas Thomas, et al on Mar. 7, 1995; and in U.S. Pat. No. 5,459,071, issued to Larry Finn on Oct. 17, 1995. Each of these machines are very large and expensive devices that engage the elongated windrow of compost material with a rotor or an auger that breaks up the windrowed compost material and conveys the compost material into another pile. In each of these large windrow turning machines, the remixed windrow of compost is re-deposited in line in the same line as the windrow before being engaged by the machine, although spaced by the operating width of the machine. 
         [0005]    In U.S. Pat. No. 4,478,520, granted on Oct. 23, 1984, to Herbert Cobey, the compost turning machine is formed with a pair of stub augers mounted to the opposing sides of a central and rearwardly disposed rotor formed with segmented teeth to break up the compost material in the windrow and convey the material rearwardly. A different self-propelled machine configuration is found in U.S. Pat. No. 5,191,754, granted on Mar. 9, 1993, to Norval Morey. In the Morey apparatus, a header formed of a pair of fixed augers that convey the compost material into a blower that blows the disintegrated compost material rearwardly through a spout positioned over the top of the machine. While the Morey apparatus can achieve significant re-mixing and aeration due to being blown rearwardly through the spout, the Morey apparatus would be prone to plugging and would not have a positive control over the material being discharged from the spout. 
         [0006]    Pull-type compost turning machines have also been developed, as is represented in U.S. Pat. No. 3,982,772, granted to Werner Scherer on Sep. 28, 1976, in which an auger header engages a small windrow of compost material and conveys the material rearwardly with sufficient velocity to engage a pair of windrow forming shields to re-form the windrow behind the machine. The pull-type machine in U.S. Pat. No. 4,932,196, issued on Jun. 12, 1990, to Bradley Schnittjer, is formed with three chain and slat conveyors that engage the windrow of compost to elevate the material and convey the material rearwardly. A pair of lateral conveyors serves to consolidate the material being conveyed by the outside chain and slat conveyors to form a new windrow behind the central conveyor. 
         [0007]    All of these known prior art machines attempt to aerate the compost material as part of the re-mixing process by disintegrating the existing pile of compost material and elevating the material to be dropped, or blown, into a new pile rearwardly of the machine. None of these machines provide a positive air displacement into the compost material between being disintegrated at the original pile and being re-deposited into the new pile. One known pull-type machine found in U.S. Pat. No. 5,309,703, granted to William Brinton on May 10, 1994, does attempt to insert a flow of air into the compost material as the material is being conveyed to the newly formed pile. The Brinton apparatus incorporates a series of conduits over the conveying mechanism to discharge air or oxygen through holes formed in the conduits into the compost material in an attempt to aerate the compost material before being re-deposited into a new pile. 
         [0008]    It would be desirable to provide a machine that would be effective in the re-mixing of the compost material from an original pile into a newly formed pile to maximize the effective aeration of the compost material, but also to provide a machine that would provide a positive displacement of air into the material being conveyed rearwardly to form the new windrow of remixed compost material. 
       SUMMARY OF THE INVENTION 
       [0009]    It is an object of this invention to provide a machine to remix and aerate a windrow of compost material. 
         [0010]    It is a feature of this machine that a positive displacement of air is moved into the flow of compost material being conveyed rearwardly for re-forming into a new windrow of compost material. 
         [0011]    It is an advantage of this invention that the positive displacement of air provides a significant forced aeration of the compost material. 
         [0012]    It is another advantage of this invention that the positive displacement of air into the remixing of the compost material speeds the composting process. 
         [0013]    It is another feature of this invention that the shredding header that engages the original windrow of compost material aggressively shreds the compost material into a substantially uniform flow of disintegrated compost material to be re-formed into a new windrow. 
         [0014]    It is still another feature of this invention that the machine for turning compost windrows is self-propelled with an enclosed, environmentally sealed operator&#39;s cab. 
         [0015]    It yet another feature of this invention that a positive displacement of air is injected into the flow of disintegrated compost material being conveyed rearwardly by a pair of fans drawing ambient air into conduits directing the forced air flow into the rearward conveyor. 
         [0016]    It is still another advantage of this invention that the windrow engaging header is formed with segmented teeth to effectively shred the original windrow of compost material to be conveyed rearwardly by a central conveyor. 
         [0017]    It is another feature of this invention that the individually mounted teeth are oriented at an angle to the axis of rotation of the rotor so that the compost is displaced toward the centerline of the machine when conveyed rearwardly by the operation of the rotor. 
         [0018]    It is still another feature of this invention that the individual teeth are mounted on the rotor in a spiral configuration that is mirrored about the center of the rotor. 
         [0019]    It is another advantage of this invention that the inward direction of the compost material conveyed by the operation of the rotor helps to affect a mixing of the compost material before being re-deposited into a new windrow behind the machine by the central conveyor. 
         [0020]    It is still another feature of this invention that the header is mounted on the forward end of the central conveyor. 
         [0021]    It is yet another advantage of this invention that the vertical movement of the header to engage the windrow of compost material will move the forward end of the central conveyor vertically in conjunction with the vertical movement of the header. 
         [0022]    It is a further advantage of this invention that the spatial relationship between the rotor and the forward end of the central convey remains constant irrespective of the vertical position of the header. 
         [0023]    It is another feature of this invention that the machine engages the compost material in front of the machine and deposits the mixed and aerated windrow immediately behind the machine. 
         [0024]    It is still a further advantage of this invention that spacing between windrows of compost material in an enclosed shelter can be minimized as the machine does not require space between the windrows of compost material to operate. 
         [0025]    It is a further feature of this invention that the rearward end of the central conveyor discharges the disintegrated compost material through winnowing shields to direct the flow of compost material being discharged off the central conveyor into a re-formed windrow. 
         [0026]    It is another object of this invention to provide a compost windrow turning and aeration machine that is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use. 
         [0027]    These and other objects, features and advantages are accomplished according to the instant invention by providing a compost windrow turning machine that moves into an existing windrow of compost material to disintegrate the original pile of compost material, convey the disintegrated material rearwardly, aerate the rearwardly conveyed material with a positive displacement of air into the flow of compost material, and re-form a new windrow of remixed and aerated compost material rearwardly of the machine in line with the original windrow. The disintegration of the original compost windrow is accomplished with a rotor having segmented teeth arranged in a spiral to shred the original compost material and convey the disintegrated material to a central chain and slat conveyor positioned behind the rotor. A positive displacement of air is injected into the compost material on the central conveyor by a pair of fans mounting in conduits angled inwardly toward the central conveyor. The discharge of material off the central conveyor is passed through a set of windrow-forming shields to create a new windrow. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    The foregoing and other objects, features, and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description that follows. 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. 
           [0029]      FIG. 1  is a right, front perspective view of the compost turning and aerating machine incorporating the principles of the instant invention, with the header in a lowered position for engaging an elongated pile of compost material; 
           [0030]      FIG. 2  is a left, front perspective view of the compost turning machine depicted in  FIG. 1 ; 
           [0031]      FIG. 3  is a right side elevational view of the compost turning machine; 
           [0032]      FIG. 4  is a front elevational view of the compost turning machine; 
           [0033]      FIG. 5  is a left side elevational view of the compost turning machine; 
           [0034]      FIG. 6  is a rear elevational view of the compost turning machine; 
           [0035]      FIG. 7  is a top plan view of the compost turning machine; 
           [0036]      FIG. 8  is a cross-sectional view through the right side of the compost turning machine corresponding to lines  8 - 8  of  FIG. 6  to show the support link for the rear of the central conveyor and the mounting of the header on the front end of the central conveyor; 
           [0037]      FIG. 9  is a cross-sectional view through the right side of the compost turning machine corresponding to lines  9 - 9  of  FIG. 7  to show the relationship between the header and the central conveyor; 
           [0038]      FIG. 10  is a perspective cross-sectional view through the right side of the compost turning machine corresponding to lines  10 - 10  in  FIG. 1 ; and 
           [0039]      FIG. 11  is a cross-sectional view taken along a horizontal plane corresponding to lines  11 - 11  in  FIG. 3  to show the relationship of the air inlet ducts to the central conveyor. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0040]    Referring to  FIGS. 1-7 , a compost turning and aerating machine incorporating the principles of the instant invention can best be seen. Any left, right, front and rear references are used as a matter of convenience and are determined by standing at the rear of the machine where the elevated central conveyor discharges material from the machine and facing forwardly toward the header at the front of the machine, which is the normal forward direction of travel of the machine during operation thereof. The machine  10  is preferably a self-propelled machine having a main frame  11  supported on tracks  12  for the mobile support of the machine  10  over the surface of the ground. One skilled in the art will recognize that while the tracks  12  are preferable for support and movement of the machine  10 , other devices, such as conventional wheels and tires, can also provide mobile support of the machine. 
         [0041]    An engine  13  is mounted on the frame, preferably beneath the rear of an elevated central conveyor  20  described in greater detail below. The engine  13  is connected to a coolant radiator  14  located in an elevated position above the central conveyor  20  to minimize the effect of dust from the operation of the machine. Charge air for the operation of the engine is provided through the main air filter  17 , best seen in  FIG. 2 , to provide a source of combustion air to the engine through an engine turbocharger (not shown). Air into the operator&#39;s cab  15  located forwardly on the frame  11  above the header  30  and the front end of the central conveyor  20  is provided through a roof mounted air conditioner  18  and associated filtration apparatus (not shown). The machine  10  is provided with conventional power transmission apparatus operatively interconnecting the engine  13  and the tracks  12  to transmit operative power thereto, and to the operable components of the machine  10 , including the central conveyor  20 , the header  30 , and the air input apparatus  45 . Preferably, this power transmission apparatus will include a hydraulic system  16  that provides a source of hydraulic fluid under pressure to the hydraulic power components described in greater detail below. 
         [0042]    As a matter of general operation of the machine  10 , the header  30  is positioned to engage an elongated pile of compost material in need of remixing and aerating. The header  30  disintegrates the pile of compost material by breaking any clumped material into component pieces and conveys the disintegrated compost material rearwardly into a central conveyor  20  that elevates the collected material for discharge from the rear of the conveyor  20 , which is elevated above the header  30 , to redeposit the compost material into a remixed pile behind the machine  10 . While the compost material is being elevated on the central conveyor  20 , the air input apparatus  45  directs a flow of air onto the central conveyor  20  so that the air will mix with the compost material being conveyed and discharged off the rearward end of the conveyor  20  to aerate the compost material as the compost material is being remixed. 
         [0043]    The central conveyor is best seen in  FIGS. 1-5  and  8 - 11  and is formed of a chain and slat conveyor mechanism positioned between the tracks  12 . The central conveyor  20  is oriented such that the conveyor elevates the compost material placed thereon from the front of the conveyor to the discharge end at the rear of the machine  10 . Preferably, the compost material is discharged off the rear of the conveyor  20  into a windrow-forming device  50  having a plurality of shields  52  fixed on a transverse support shaft  53 . The shields  52  are oriented so as to be angled toward the longitudinal centerline of the machine  10 , which will serve to deflect the discharged compost material into a centralized pile rearwardly of the machine  10 . 
         [0044]    The chain and slat conveyor  20  is entrained around a drive sprocket assembly  21  at the rear of the conveyor  20  and a driven sprocket assembly  22  at the front of the conveyor  20 . The drive sprocket assembly  21  is powered by a hydraulic motor  23 , shown in  FIGS. 2 and 6  as being on the left side of the machine  10 , operatively connected to the hydraulic system  16 . As seen best in  FIG. 9 , the sprocket assemblies  21  and  22  are mounted on side frame members  24 , the drive sprocket assembly  21  being positionally adjustable to maintain proper tension in the chain and slat conveyor  20 . The side frame members  24  support a central floor member  25  over which the rearwardly moving run of the chain and slat conveyor  20  moves to convey the compost material rearwardly. The front of the conveyor  20  cooperates with a curved member  19  so that the slats  20   a  will scoop material conveyed rearwardly by the header  30  and move the compost material rearwardly over the floor  25 . 
         [0045]    The rearward portion of the central conveyor  20  is supported from a pair of laterally spaced vertical support links  27  pivotally connected at the upper end by a pivot  28  to the respective side frame members  24  and at the lower end by a transverse pivot shaft  29  that passes beneath the conveyor  20 . The front portion of the central conveyor  20  mounts the header  30 , as will be described in greater detail below, and is vertically movable with the header  30  to allow the header  30  to engage the pile of compost material. As the header  30  and the front end of the conveyor  20  move vertically, the side frame members  24  pivot about the pivot connection  28 . However, the lift mechanism  35  for the header  30  operates to move the header  30  in a substantially straight vertical line. As a result, the rearward end of the conveyor  20  must move longitudinally to accommodate this induced movement of the header  30 . The pivotal movement of the support links  27  about the transverse pivot shaft  29  allows the rearward end of the conveyor  20  to shift slightly rearwardly as the front end of the conveyor  20  moves vertically. 
         [0046]    The header  30  is formed with a header frame  31  that rotatably supports a transverse rotor  40 . The frame  31  defines a box-like structure with a central discharge opening  32  in register with the central conveyor  20 . As is best seen  FIG. 4 , the back wall of the header frame is sloped to direct the flow of disintegrated compost material toward the central discharge opening  32 . As is shown in  FIG. 8 , the header frame  31  is mounted to the front end of the central conveyor  20  with the axis of rotation of the driven sprocket assembly  22  being secured within a mounting flange  33  so that the header frame  31  and the front end of the conveyor  20  will move together. Referring now to  FIGS. 1-3  and  5 , the header  30  is secured to the frame  11  of machine  10  by a lift mechanism  35  on each opposing side of the header  30 . A mounting bracket  36  is affixed to the frame  11  to support each lift mechanism  35  which includes a four-bar linkage  37  on opposing sides of the header  30 , interconnecting the header frame  31  and the mounting bracket  36  that induces a vertical movement of the header frame  31  along a substantially straight vertical line. A hydraulic cylinder  39  is anchored on each mounting bracket  36  and is connected to the header frame  31  so that the extension of the hydraulic cylinders  39  pushes the header  30  vertically, taking the front end of the conveyor  20  with the header  30 . 
         [0047]    In operation, the operator moves the header  30  vertically, as needed, to engage the pile of compost material. Since the axis of the driven sprocket assembly  22  is supported on the mounting flange  33  of the header, the vertical movement of the header  30  caused by the expansion and contraction of the hydraulic cylinders  39  also moves the front end of the conveyor  20  with the header  30 . The mounting of the side frame members  24  on the support links  27 , as described above, allows the conveyor  20  to pivot vertically about the pivot connections  28  and to swing longitudinally by virtue of the pivotal mounting of the support links  27  on the transverse pivot shaft  29 . 
         [0048]    The rotor  40  can be a cylindrical tubular member, but is preferably fabricated into an octagonally-shaped cylinder  41  to facilitate the mounting of segmented teeth  42  onto the flat surfaces of the cylinder  41 . The opposing ends of the rotor  40  are drivingly connected to hydraulic motors  44  operably associated with the hydraulic system  16  to power the rotation of the rotor  40  in a manner to drive the segmented teeth  42  into the pile of compost material to be disintegrated. The teeth  42  are mounted on the rotor cylinder  41  at an angle to the axis of rotation of the rotor  40  and the teeth  42  are arranged in a spiral configuration around the cylinder  41 , similar to that of a segmented auger flighting. With this configuration, the rotation of the rotor  40  will cut the segmented teeth  42  into the pile of compost material to disintegrate the compost material from the pile and convey the disintegrated material rearwardly and inwardly toward the center of the rotor. Thus, the rotor  40  operates to convey the disintegrated compost material through the central discharge opening  32  into engagement with the central conveyor  20 . 
         [0049]    Referring now to  FIGS. 8 and 9 , the header frame  31  is formed with a curved member  34  cooperable with the segmented teeth  42  to permit the teeth  42  to elevate the disintegrated compost material for discharge from the header  30  through the central opening  32  into the conveyor  20 . 
         [0050]    To enhance the aeration of the compost material as the material is being remixed and re-deposited onto a new pile rearwardly of the machine  10 , the machine  10  is provided with a pair of laterally spaced air input devices  45 . The air input devices  45  include a generally cylindrical duct  46  that is oriented inwardly from an inlet opening located above the front portion of the central conveyor  20 . A fan  48  is mounted at the inlet opening to draw air from outside of the machine  10  into the duct  46  which directs the flow of air onto the top of the central conveyor  20  between the respective lateral edges of the conveyor  20  and the longitudinal centerline thereof, as is best seen in the cross-sectional view of  FIG. 11 . The flow of air induced by the rotating fans  48  will carry rearwardly with the compost material on the conveyor  20 , contained by the shielding  26  around the conveyor  20  to the rear discharge end of the conveyor  20  to be mixed with the compost material being re-deposited into a windrow by the windrow-forming apparatus  50 . 
         [0051]    The invention of this application has been described above both generically and with regard to specific embodiments. Although the invention has been set forth in what is believed to be the preferred embodiments, a wide variety of alternatives known to those of skill in the art can be selected within the generic disclosure. The invention is not otherwise limited, except for the recitation of the claims set forth below.