Abstract:
A crop residue spreader for a combine harvester is pivotally mounted to the combine for rotation about a transverse axis. The spreader has a spreading position in which crop residue is spread over a wide area at the rear of the combine. The spreader is rotatable about the transverse axis to a raised windrowing position to allow the residue to fall to the ground in a windrow for later collection. The disks of the spreader are covered by shrouds above and to the sides to reduce the upward dispersal of the residue. Gas assist cylinders are provided to lift the spreader to the windrow position after which a latch is engaged to hold the spreader there. A hold down latch operates to hold the spreader in the spreading position in opposition to the gas assist cylinders.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a crop residue spreader for a combine and in particular to a spreader that is pivotally mounted to the combine for movement between a spreading position and a windrowing position. 
     2. Description of the Related Art 
     Management of crop residue, i.e. straw and chaff, at the time of harvesting is becoming of greater importance with the increased use of reduced tillage or no-tillage farming practices. By widely dispersing the crop residue, as opposed to dropping the residue in a narrow width row immediately behind the combine, the residue is more evenly distributed across the ground. This produces benefits during the spring planting season including greater uniformity in soil temperature and greater uniformity in ground conditions for operation of seeding equipment. It is known to spread the residue at the rear of the combine with one or two rotating disks. The rotating disks disperse the residue over a wide area behind the combine. Such spreaders work well as long as the operator desires to spread the residue. If the operator wishes to windrow the residue for later collection, it is often necessary to remove the spreader to provide a clear path for the crop residue to fall to the ground. This is a time consuming process. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a spreader that is movably mounted to the combine for movement between a spreading position in which the crop residue is dispersed and an inoperative windrowing position in which the crop residue is dropped from the combine in a narrow width windrow. 
     The spreader of the present invention has one, or preferably two, rotating disks mounted to a frame at the rear of the combine. The disks have raised radial ribs to engage and disperse the crop residue as they rotate. The rotating disks also act as a fan, creating airflow to further propel the residue. The frame is rotatably mounted to the combine for rotation about a transverse pivot axis. The frame and disks are pivoted to a raised position in which the crop residue is able to drop from the combine in front of the spreader. A top shroud is carried by the frame and spaced above the disks to prevent upward dispersal of the residue. In addition, side shrouds extend laterally outward from the top shroud, beyond the combine side sheets to control the distribution of the residue. Front shrouds are mounted to the combine forward of the side shrouds and outboard of the side sheets. 
     Gas assist cylinders are provided to urge the spreader to the raised, windrowing position. A hold down latch acts in opposition to the gas assist cylinders to retain the spreader in the spreading position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a semi-schematic side elevation of a combine having the residue spreader of the present invention. 
     FIG. 2 is a downward looking perspective view of the spreader of the present invention in the spreading position. 
     FIG. 3 is an upward looking perspective view of the spreader of the present invention in the spreading position. 
     FIG. 4 is a perspective view of the spreader of the present invention in the windrowing position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An agricultural combine  10  is shown in FIG.  1 . The combine  10  includes, among other things, a supporting structure formed by a pair of upright side sheets  12 , only one of which is shown in FIG.  1 . The combine also includes ground engaging wheels  14 . A harvesting platform  16  is used to harvest a crop and direct it to a feederhouse  18 . The harvested crop is directed by the feederhouse to a beater  20 . The beater directs the crop upwardly, through the inlet transition section  22  to a rotary crop-processing unit  24 . A rock trap  25  is positioned between the feederhouse and the beater  20 . 
     The rotary crop-processing unit  24  threshes and separates the harvested crop material. It comprises a rotor or rotating member  26  radially surrounded by a casing  28 . The rotor and the casing together define an inlet section  30 , a threshing section  32  and a separating section  34 . The rotor  26  comprises a hollow cylindrical drum having a plurality of crop-processing elements that engage the crop and rotate it in the casing  28 . The bottom of the casing has a concave  36  under the threshing section  32  and a separating grate  38  under the separating section  34 . 
     Grain and chaff falling through the concave  36  and the separating grate  38  are directed to a cleaning system  40 . The cleaning system  40  includes a fan, a sieve and a chaffer in a known manner. The air blast from the fan blows through the sieve and the chaffer, blowing the chaff upward and rearward while the grain is allowed to fall through the sieve and chaffer to a clean grain elevator (not shown). The clean grain elevator deposits the clean grain in a grain tank  48 . The clean grain in the tank  48  can be unloaded into a grain cart or truck by unloading auger  50 . The operation of the combine is controlled from the operator&#39;s cab  56 . 
     Threshed and separated crop residue is discharged from the rotary crop-processing unit  24  through outlet  52  to a discharge beater  54 . The discharge beater in turn propels the residue out of the combine, through a lower rear opening  60  rearward of the cleaning system  40 . A spreader  62  is mounted to the side sheets at the opening  60 . When the spreader is in the spreading position, it receives the crop residue and distributes it over a wide area behind the combine. While the spreader  62  is shown in connection with a combine having a rotary separator, the spreader of the present invention can be used with combines having other types of separators, including straw walkers. 
     The combine structure includes two outer side panels  66  and  68  and an upright front panel  70  joined to the combine side sheets  12  as shown in FIG. 3. A spreader frame  74  is attached to the side panels  66 ,  68  at pivots  76 , one at each side of the spreader. The frame  74  includes two inner side panels  78  and  80  and a lower panel  82 . The two pivots  76  couple the inner panels of the frame  74  to the outer side panels  66 ,  68  and define a transverse pivot axis  84 . 
     Hydraulic motors  86  are mounted to the frame lower panel  82 . Each motor has an output shaft  90  that extends downward from the motor below the lower panel  82 . A disk  92  is coupled to each output shaft  90  for rotation therewith. The disks  92  are formed with raised radial ribs  94 . The disks  92  counter-rotate as shown by the arrows  96  in FIG.  2 . Optional blades  100  may be mounted to the radial ribs  94  with fasteners  102  extending through the apertures  98  in the ribs. The blades may be mounted on some or all of the ribs  94 , as long as the disk remains balanced. The crop residue exiting the combine through the opening  60  is engaged by the ribs and blades of the rotating disks  92  to propel the residue over a wide width behind the combine. The blades function as a fan to draw air from the combine and create airflow to the rear and to the side to assist in the dispersal of the residue. 
     Shrouding is provided over and around the disks  92  to help direct the crop residue as it is distributed. The shrouding includes a top shroud  104  over each of the disks  92 , rearward of the shafts  90 . Each top shroud  104  is coupled to the lower panel  82  by a plurality of nut and bolt fasteners  106 . The top shrouds  104  are generally formed of three sections, a shroud center section  110 , a shroud inner section  116  and a shroud outer section  120 . The three sections are all generally triangular in shape. The top shrouds  104  are preferably each formed as a single piece of stamped sheet metal having a fold  112  between the center section  110  and the inner section  116  and a fold  114  between the center section  110  and the outer section  120 . The sections could be made as separate components bolted together. The shroud center section  110  has a front edge  111  that is fastened to the lower panel  82 . 
     The three shroud sections slope downwardly from the front edge  111 . The inner sections  116  also slope toward an inner lower corner  122  while the outer sections  120  slope toward outer lower corners  124 . The inner sections  116  and the outer sections  120  have a greater downward slope than does the center section  110 . The inner lower comers  122  are slightly lower than the outer lower corners  124 . 
     A divider  130  between the two top shrouds  104  extends downwardly from the center and inner shroud sections  110 ,  116  toward the disks  92  as best seen in FIG.  4 . The divider  130  serves to separate the flow of the crop residue between the two disks  92 . 
     Side shrouds  134  are fastened along outer edges  136  of the top shrouds  104 . The side shrouds  134  first extend upward and then project outward from the outer edges  136 . Additional front shrouds  140  (FIG. 3) are provided forward of the side shrouds  134 . The front shrouds  140  are fastened to the combine side sheets and extend outwardly beyond the side sheets. A skirt  138  may be added to and depend from the front shrouds  140 . The top shrouds  104 , side shrouds  134  and front shrouds  140  operate to keep the residue from being dispersed upward. 
     A bottom panel  154 , FIG. 3, extends downward at the rear of the cleaning system  40 , in front of the disks  92 . The bottom panel has an upper metal portion  156  and a lower depending skirt  158 . The skirt gives the panel flexibility in accessing areas of the combine in front of the panel. The bottom panel  154  helps to prevent forward dispersal of the crop residue. 
     The spreader frame  74  has a spreading position shown in FIGS. 1-3 in which the shafts  90  are oriented generally vertically and the disks generally horizontally. This is an operative spreading position in which crop residue from the combine is received by the disks  92  and distributed thereby. In this position, the shrouding around the disks and the bottom panel  154  of the combine behind the cleaner  40  enable the rotating disks  92  to draw air from the combine cleaning system  40 . 
     The frame  74  is rotatable about the pivot axis  84  to a rearwardly raised position shown in FIG.  3 . This is a windrowing position in which the disks  92  are not rotated. The crop residue is allowed to fall from the combine through the opening  60  directly to the ground, without being dispersed over a wide area. This leaves the residue in a windrow for subsequent collection. Gas assist cylinders  142  are provided at each side of the spreader to facilitate lifting of the spreader to the windrowing position. The cylinders  142  extend between the frame  74  and the panel  70  of the combine structure. The gas assist cylinders provide a biasing force on the frame  74  to urge the frame to the windrowing position. Other biasing mechanisms may be used such as a spring. Furthermore, a powered lift mechanism such as a hydraulic cylinder or a motor driven lift linkage may also be used. 
     A hold down latch  146  extends between the combine frame above the spreader and the top shrouds  104 . The hold down latch retains the spreader in the spreading position in opposition to the gas assist cylinders  142 . The hold down latch  146  is manually released to enable the spreader to rotate to the windrowing position. 
     An upper latch  150  (FIG. 3) on the combine frame insures that the spreader remains in the windrowing position and that the weight of the spreader and vibration forces are not resisted solely by the gas assist cylinders  142 . The upper latch  150  couples to a striker bar  152  on the hold down latch  146  to retain the frame  74  in the windrowing position. The latch  150  is manually released to lower the spreader to the spreading position. Once released, the operator manually pushes down on the top shrouds  104 , in opposition to the gas assist cylinders  142 , to return the spreader to the spreading position. The hold down latch  146  is then manually engaged to retain the spreader in the spreading position. One person can easily reposition the spreader from the spreading position to the windrowing position or vice versa in a matter of seconds. 
     The spreader of the present invention functions to effectively and evenly spread crop residue over a wide area at the rear of the combine. In addition, the spreader can easily be moved to a windrowing position without entirely removing the spreader from the combine. This avoids the difficult and time consuming process often required when it is desired to windrow the crop residue. 
     While the spreader has been shown and described as having a pair of disks, the invention can be used with a single disk. The invention should not be limited to the above-described embodiment, but should be limited solely by the claims that follow.