Abstract:
The invention concerns a combine harvester, with a separating mechanism from which a first crop stream can go optionally to a straw chopper in a chopping operating mode or bypass the straw chopper in a straw deposit mode and be placed as a swath on the ground of a field, a cleaning mechanism, from which a second crop residue stream in the chopping mode and in the straw deposit mode can be taken to the straw chopper, and a guide mechanism that is arranged downstream from the straw chopper and can move optionally between a straw depositing position and a chopping position. It is proposed that the guide mechanism be oriented so that in its straw depositing position it deflects downward a portion of the second crop stream oriented in the direction of the first crop stream being ejected, and in its chopping position it does not significantly deflect the flow of the two crop streams.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention concerns a combine harvester, with a separating mechanism from which a first crop stream can go optionally to a straw chopper in a chopping operating mode or bypass the straw chopper in a straw deposit mode and be placed as a swath on the ground of a field, a cleaning mechanism, from which a second crop residue stream in the chopping mode and in the straw deposit mode can be taken to the straw chopper, and a guide mechanism that is arranged downstream from the straw chopper and can move optionally between a straw depositing position and a chopping position, designed to deflect the second crop residue stream in the straw depositing position so that the second crop residue stream is ejected in a different direction than the first crop residue stream, while in the chopping position, the guide mechanism can be arranged so that both crop streams are distributed jointly over the field, essentially for the width of a crop receiving mechanism.  
       BACKGROUND OF THE INVENTION  
       [0002]     DE 100 64 356 A and DE 102 56 744 A describe combine harvesters that can optionally operate in a straw deposit mode and a chopping mode. In the chopping mode, the straw is guided through the straw chopper, and in straw deposit mode it bypasses its rear end and is deposited on the ground as a swath. In both operating modes, the chaff is passed through the straw chopper. In the straw deposit mode, the straw guide plates are placed in a position in which the chaff is distributed across the working width on either side of the swath, but does not reach the region of the swath. In the chopping mode, the straw guide plates are placed in a different position, in which chaff and straw are distributed across the working width of the field.  
         [0003]     WO 02/34029 A proposes a combine harvester with a chaff distributor and a straw chopper. The chaff distributor can blow the chaff directly against the straw guide plates, arranged downstream from the straw chopper, so that the chopped straw and the chaff are distributed by the guide plates over the working width. In another operating mode, the straw goes above and bypasses the straw chopper and is deposited as a swath on the field, while the chaff is guided by the chaff distributor along the straw guide plates and is deposited in the field across the working width, at either side of the swath. In additional operating modes, the straw is chopped by the straw chopper and distributed across the working width or deposited in a swath, while the chaff is distributed by the chaff distributor across the working width on either side of the swath. Finally, the possibility is provided of also blowing the chaff into the straw swath in the swath depositing mode.  
         [0004]     The brochures “Deutz-Fahr Topliner 8XL,” printer&#39;s mark 91 532 01 Printed in Germany 9906, “Case IH Cross-Flow,” printer&#39;s mark CF80-D-BR-10/99, and “KP 2000 Straw Chopper Attachment with unique Chaff Blower” of the KPAB company, printer&#39;s mark 941523, describe combine harvesters which can likewise be run in a chopping mode and a straw depositing mode. The straw is either delivered through the straw chopper, chopped up, and distributed across the working width (chopping mode), or is taken behind [the chopper] and deposited in a swath in the field (straw mode). In both operating modes, the chaff is delivered to the straw chopper and distributed over the field by the guide plates arranged downstream from the straw chopper.  
         [0005]     In the prior art as described in the brochures of the firms Deutz, Case, and KPAB, the chaff is distributed across the working width of the combine in the straw depositing mode. As a result, a portion of the chaff also gets into the straw, which is undesirable for many application areas, such as horse litter. Furthermore, the air stream provided by the straw chopper blows the straw swath up, so that the straw is distributed over a greater width than is desirable for collection with a baling press. The combine described in WO 02/34029 A does not have these drawbacks, but it requires relatively costly chaff distributors. In the combines of DE 100 64 356 A and DE 102 56 744 A, the straw guide plates have to be adjusted in order to switch between the straw depositing mode and the chopping mode, which proves to be relatively cumbersome.  
       SUMMARY OF THE INVENTION  
       [0006]     The problem underlying the invention is considered to be the providing of an improved combine harvester, not having the above-mentioned drawbacks of the prior art or having fewer of them.  
         [0007]     The problem is solved according to the teaching of Claim  1 , while the other claims present features which refine the solution in advantageous manner.  
         [0008]     It is proposed to place, downstream from the straw chopper, a guide mechanism which can move between a straw depositing position and a chopping position, which in its straw depositing position deflects downward a portion of the second crop stream (chaff) oriented in the direction of the first crop stream being ejected, while the remaining first crop stream (straw) is not affected. In its chopping position, it does not significantly affect the crop stream consisting of straw and chaff.  
         [0009]     In this way, there is no need to adjust the straw guide plates between the straw depositing mode and the chopping mode. In the straw depositing mode, the middle portion of the second crop residue stream (i.e., the portion of the chaff which is ejected by the straw chopper in such an angle range that it would come to lie beneath the straw swath) cannot get into the swath, since it is deflected downward and deposited directly on the field. Furthermore, the swath is prevented from being blown upwards. Then, in the chopping mode, when the guide mechanism is placed in an inactive position, i.e., one not noticeably deflecting or influencing the flow of the two crop streams, it has no disruptive action on the distribution of the crop streams.  
         [0010]     In one preferred embodiment of the invention, several straw guide plates are arranged side by side downstream from the straw chopper, generally underneath an ejecting hood. The guide mechanism is preferably arranged downstream from the straw guide plates, since sufficient space is available there. The relatively slight distance from the first crop residue stream also prevents particles from the second crop residue stream from being carried by wind into the first crop residue stream.  
         [0011]     The guide mechanism is, in particular, a platelike element, extending roughly vertically in the straw depositing position, so as to deflect downward the middle part of the first crop stream, and in the chopping position it is oriented roughly horizontally, so that the two crop streams can flow undisturbed along its bottom side. Between these positions, the guide mechanism can swivel about an axis extending horizontally and transversely to the forward direction of the combine harvester.  
         [0012]     It has proven to be advantageous to connect the guide mechanism to an adjustment drive, which can move it between its straw depositing position and chopping position. The adjustment drive can be operated manually or by motor, e.g., by an electric or hydraulic motor. When there is a manual or motorized operation, it is advisable to have a coupling to the elements which optionally guide the first crop residue stream to the straw chopper or bypass it. This coupling can be mechanical, or there can be a suitable actuation of the respective motor.  
         [0013]     Preferably, suitable straw guide rakes are used to form the first crop residue stream. These straw guide rakes are not needed in the chopping mode and, because of the danger of injury which they present, they are placed in an inoperative position. It is advisable to couple the drive mechanism of the straw guide rakes with the adjusting drive of the guide mechanism. Then, when the guide mechanism is in the chopping position, the adjusting drive places the straw guide rakes in the inoperative position, and when the guide mechanism is in the straw depositing position the guide rakes are placed in a swath guide position, in which they channel the first crop residue stream to the side.  
         [0014]     For this, the guide mechanism can be connected to a shaft, moved by the adjusting drive, on which holding devices for the straw guide rakes provided with fingers are also secured. The holding devices extend transversely to the shaft. Since the angle range of the shaft to be traversed between the swath guide position and the inoperative position of the straw guide rakes is larger than the angle range for adjusting the drive between its chopping position and its straw depositing position, the guide mechanism can have a stop, which interacts with a suitable element joined torsion-proof to the shaft, so as to provide an angle range of the shaft in which there is no movement of the guide mechanism. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The drawings present one embodiment of the invention, which shall now be described in greater detail. They show:  
         [0016]      FIG. 1 , a schematic side view of a combine harvester with a guide mechanism according to the invention,  
         [0017]      FIG. 2 , a perspective view of the guide mechanism and two straw guide rakes,  
         [0018]      FIG. 3 , a perspective rear view of the rear area of the combine in the chopping mode, and  
         [0019]      FIG. 4 , a perspective rear view of the rear area of the combine in the straw depositing mode. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0020]      FIG. 1  shows a self-propelled combine harvester  10  with a frame  12 , which is supported on the ground by wheels  14  and moved forward by them. The wheels  14  are caused to turn by drive means not shown, in order to move the combine  10  across a field being harvested, for example.  
         [0021]     At the front end region of the combine  10  there is attached a harvesting device  16  in the form of a cutting mechanism, so as to harvest the crop from the field and feed it up and back via a slanted conveyor  18  to threshing and separating means. The threshing and separating means comprise a transversely placed threshing drum  20 , associated with a threshing basket  21 , to which the harvested crop is first taken. But it is also conceivable to omit the threshing drum  20  and use an axial separator, having a threshing segment and a separating segment. One can use a single axial separator or two (or more) axial separators arranged side by side. A plucking roller  23  and a turnover drum  22  along with a feed housing take the threshed crop from the threshing drum  20  and the threshing basket  21  to the separating mechanism  24  in the form of an axial separator. The separating mechanism  24  is driven at its back side by a gear assembly  80 , which connects it to an internal combustion engine  48 . One can also use a straw rocker as the separating mechanism  24 . Hereinafter, all indicated directions, such as forward, backward, above and below shall refer to the direction of forward motion V of the combine harvester  10 .  
         [0022]     Grain and chaff that are separated during the threshing process drop onto at least one auger conveyor  30 , which takes both of them to a preparation deck  33 . Grain and chaff leaving the separating mechanism  24 , on the other hand, drop onto a rocking deck  32 , which takes them to the preparation deck  33  for further routing. The preparation deck  33  passes on the grain and the chaff to a sifting box  34 , associated with a blower  36 , in order to support the separation of the chaff from the grain. Cleaned grain is taken by means of a grain auger  38  to an elevator (not shown), which delivers it to a grain tank  40 . A return auger  42  takes unthreshed pieces of ears back to the threshing process via another elevator (not shown). The chaff can be ejected at the back of the sifting mechanism by a rotating chaff distributor. The cleaned grain can be unloaded from the grain tank  40  by an unloading system with transverse augers  44  and an unloading conveyor  46 .  
         [0023]     The above-mentioned systems are driven by means of an internal combustion engine  48  and controlled and guided by an operator from a driver&#39;s cabin  50 . The various devices for threshing, conveying, cleaning and separating are located inside the frame  12 . Outside of the frame  12  is an outer shell, which for the most part can be folded open.  
         [0024]     From the separating mechanism  24 , unthreshed crop residue (straw) is ejected downward through an outlet  64  at the bottom of the rear end of the housing of the separating mechanism  24 , which is closed at its back. Through centrifugal force and gravity, the crop residue drops into a vertical ejection shaft, which is bounded in front by a front wall  62 . Beneath the outlet  64  there is arranged an ejection drum  66 , about the periphery of which are distributed pusher dogs  67 . The ejection drum  66  is enclosed at the back by a rear wall  86 . The ejection drum  66  is caused to turn, counterclockwise in  FIG. 1 , about its lengthwise axis, which extends horizontally and transversely to the direction of travel V. At roughly half the height of the front wall  62 , a straw guide element  68  lies against it, somewhat below the axis of rotation of the ejection drum  66  and able to swivel as a whole about the axis of rotation of the ejection drum  66 . The straw guide element  68  can swivel about this axis between the straw depositing position shown in  FIGS. 1 and 4  and a chopping position ( FIG. 3 ).  
         [0025]     Underneath and slightly behind the ejection drum  66  there is a conventional straw chopper  70  arranged in a housing  72 , which can be driven in rotation about a horizontal axis running transversely to the direction of travel (counterclockwise in the figure). It comprises a cylindrical body, from which chopping blades are suspended in a floating manner, that cooperates with stationary counterblades arranged in the housing  72  in order to chop up the crop residue and distribute it on the field, roughly across the mowing width of the combine  10 , by means of a straw distributing hood  74  outfitted with straw guide blades  82  on its underside.  
         [0026]     The straw guide element  68  has concave curvature (a circular arc) and concentrically encloses the ejection drum  66  in an angle range of around 45°. At its outer ends in the transverse direction, it is hinged to swivel about the axis of the ejection drum  66 . The straw guide element  68  extends, in the straw depositing position shown in  FIG. 1 , from the front wall  62  to just above the axis of rotation of the straw chopper  70 . In this position, the straw guide element  68  ensures that the threshed crop residue is deposited at a slant downward and backward from the ejection drum  66  beneath an ejection hood  76 , located downstream from the rear wall  86 , and above the straw distributing hood  74 .  
         [0027]     In the chopping position, the straw guide element  68  is swiveled back about the axis of rotation of the ejection drum  66  (clockwise in relation to  FIG. 1 ). In this way, an opening is produced between the front wall  62  and the forward edge of the straw guide element  68 , through which the crop residue reach the straw chopper  70 . The straw guide element  68  in this position prolongs the rear wall  86  downward and forward. In its region below the line against which the straw guide element  68  comes to rest when it is in the straw depositing position, the front wall  62  is likewise provided with guide runners  84  so as to load the straw chopper  70  as uniformly as possible. In the straw chopper  70 , the crop residue is chopped up and ejected backward and downward at a slant. Beneath the straw distributing hood  74  arranged at the ejection of the straw chopper  70 , there are provided the straw guide plates  82 , which dictate the direction in which the crop residue will be deposited on the ground of the field.  
         [0028]     Above the rear end of the straw distributing hood  74  extends a straw guide rake  78 , which serves to steer the straw in the swath depositing position. Beneath the rear end of the straw distributing hood, downstream from the straw guide plates  82 , there is arranged a sheetlike guide mechanism  88 , which is depicted in its straw depositing position in  FIG. 1 , in which it extends roughly vertically downward.  
         [0029]     In  FIG. 2 , the straw guide rake  78  and the guide mechanism  88  are shown in a perspective view. The guide mechanism  88  is a rectangular sheet which is curved so as to produce a hollow channel  90 . The surfaces of the sheet on either side of the channel  90  are joined together by screws  92 . Through the channel  90  there extends a shaft  94 , which is provided with an outwardly projecting element  96  at either end of the channel  90 . The element  96  in the chopping position of the guide mechanism  88  depicted in  FIG. 2  comes to rest against a stop  98 , which is defined by a recess  100  in the guide mechanism  88 , and the crop hitting the stop  98  forces it against the element  96 . The recess  100  is dimensioned in the peripheral direction of the shaft  94  such that the guide mechanism  88  can turn between the positions shown in  FIGS. 3 and 4 .  
         [0030]     The straw guide rakes  78  each have a holding device  102 , extending parallel to each other and transversely to the shaft  94 . The holding device  102  has at its lower end a plate  104  furnished with several holes  106 . Each of the holes  106  is penetrated by a pin  108 , connected to the shaft  94 . The shaft  94  and the holding devices  102  are connected by another pin  110  joined to the shaft  94 , extending inside the holding device  102  and beyond its upper end, and by a spring  114  arranged between the upper end of the holding device  102  and a disk  112  joined to the other pin  110 . In this way, it is possible to lift the holding device  102  off of the shaft  94  against the force of the spring  114 , turn it about the lengthwise axis of the holding device  102 , and set any one of the holes  106  on the pin  108 , so as to adjust the angle of the straw guide rake  78  about the lengthwise axis of the holding device  102  to the particular harvesting conditions, in particular, the volumes of straw.  
         [0031]     Each of the holding devices  102  has six fingers  116 , which extend through openings in adjustment elements  118  at their ends near the holding device  102  and [through] angle pieces  120  rigidly joined to the holding device  102 . The adjustment elements  118  are joined to the angle pieces  120  by screws  122  and after the screws  122  opposite angle pieces  120  are loosened they can be moved along the lengthwise axis of the holding devices  102 , resulting in a change of the angle of the fingers  116  relative to the lengthwise axis of the holding device  102 . The straw guide rakes  78  are described in DE 10 2004 014 306 A, whose disclosure is incorporated by reference into the present documents.  
         [0032]     The mounting of the straw guide rake  78  and the guide mechanism  88  on the rear end of the combine  10  can be seen in  FIGS. 1, 3  and  4 . In  FIGS. 1 and 4 , the combine  10  is in its straw depositing mode and in  FIG. 3  it is in its straw chopping mode. The straw guide element  68  in the straw depositing mode ( FIGS. 1 and 4 ) lets the remaining first crop stream (straw) ejected from the separating mechanism  24  exit at the top of the ejection hood  76  in a swath on the field. The straw guide element  68  in the chopping mode ( FIG. 3 ) causes the remaining first crop stream (straw) ejected from the separating mechanism  24  to enter the straw chopper  70 , which chops it up and delivers it along the straw guide plates  82  underneath the ejection hood  76 , which distribute it on the field across the working width of the combine  10 . The second crop stream (chaff) prepared by the cleaning mechanism  34  is likewise delivered to the straw chopper  70  by a rocking bottom conveyor  124  in both mentioned operating modes and distributed on the field roughly across the working width of the combine  10 .  
         [0033]      FIG. 3  shows how the shaft  94  extends at the rear of the ejection hood  76  transversely to the forward direction of travel of the combine  10 . The shaft  94  is placed manually, by a handle (not shown), into an angular position in which the holding devices  102  of the straw guide rakes  78  extend at a slant forward and upward from the shaft  94 , and are locked in this angular position. The fingers  116  are accordingly in an inactive position, in which they present little risk of injury. The guide mechanism  88  is in its chopping position and extends from the shaft  94  backward and downward at a slant, parallel to the ejection hood  76 , and does not significantly influence the crop streams  126  ejected from the straw chopper  70 .  
         [0034]     In  FIG. 4 , the shaft  94  has been brought by the handle into an angular position in which the holding devices  102  of the straw guide rakes  78  extend backward and upward at a slant from the shaft  94 , and are locked in this angular position. The fingers  116  are accordingly in a swath guiding position, in which they form the second crop residue stream  128  ejected at the upper end of the ejection hood  76  into a swath. The guide mechanism  88  is in its straw depositing position and extends roughly vertically downward from the shaft  94 . In this way, a middle region  130  of the second crop residue stream, which without the guide mechanism  88  could have gotten into the second crop residue stream  128 , goes directly downward onto the ground of the field. Thus, the chaff does not get into the straw to a significant degree. Furthermore, the swath is not blown up by the current of air produced by the straw chopper  70 . The width of the guide mechanism  88  is designed so that the outer regions  132 ,  134  of the second crop residue stream are not deflected or influenced by the guide mechanism  88 .  
         [0035]     The angular range of the guide mechanism  88  is roughly 60° between the straw depositing position and the chopper position, while the straw guide rakes turn through roughly 90° between their swath guide position and their out of operating position. These different angles are made possible by the elements  96  and the stops  98 , which provide for an angular range of the shaft  94  in which the guide mechanism  88  does not move.  
         [0036]     Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.