Abstract:
A combine comprising a separating assembly providing a first crop residue stream, the first crop residue stream is directed to a straw guide element having a chopping mode position for directing the first crop residue stream to a straw chopper for chopping the first crop residue stream and a swath forming mode position for conveying the first crop residue stream around the straw chopper laying the first crop residue stream in a swath. The combine also comprises a cleaning assembly providing a second crop residue stream that engages a conveying assembly which mechanically conveys the second crop residue stream from the cleaning assembly to the straw chopper.

Description:
FIELD OF THE INVENTION 
   The present invention is directed to a combine having a separating assembly providing a first crop residue stream that can be fed to a straw chopper or conveyed around the straw chopper. The combine also comprises a cleaning assembly providing a second crop residue stream that can be fed by a mechanical conveying assembly to the straw chopper. 
   BACKGROUND OF THE INVENTION 
   EP 0 727 135 A describes a combine, in which the straw is laid down on the ground in a swath by straw walkers via a guide plate in a swath laying mode or fed to a straw chopper in a chopping mode, in which the straw is chopped and distributed on the field. The guide plate can be moved into a third position, in which the straw as well as the chaff can be conveyed through the straw chopper. The chaff is pneumatically conveyed into the straw chopper by means of blowers of the cleaning assembly. 
   WO 01/01754 A describes a combine with a straw chopper and a chaff spreader. The chaff spreader is able to throw the chaff into the straw upstream of the straw chopper such that it moves through the straw chopper together with the straw and is distributed on the field approximately over the operating width of the cutting mechanism. It is also possible to distribute the chaff over the operating width by means of the chaff spreader. In this case, the chaff is not moved through the straw chopper while the straw is chopped in the straw chopper and distributed on the field. If the straw is not chopped but rather conveyed around the front side of the straw chopper by a pivoted straw guide plate and laid down on the field, the chaff can be distributed on the field over the operating width of the cutting mechanism or blown into the straw swath. 
   WO 02/34029 A proposes a different chaff spreader arrangement. This chaff spreader is able to blow the chaff directly against straw guide plates arranged downstream of the straw chopper such that the chopped straw and the chaff are distributed over the operating width via the guide plates. In another operating mode, the straw is conveyed around the rear of the straw chopper and laid down on the field in the form of a swath, wherein the chaff is conveyed along the straw guide plates by the chaff spreader and distributed on the field over the operating width to both sides of the swath. In other operating modes, the straw is chopped by the straw chopper and distributed over the operating width or laid down in the form of a swath while the chaff is distributed by the chaff spreader over the operating width to both sides of the swath. In this arrangement, it is also possible to blow the chaff into the straw swath in the swath laying mode. 
   DE 100 64 356 A proposes to always convey the chaff through the straw chopper while the straw is either conveyed through the straw chopper in the chopping mode or around the rear side of the straw chopper in the swath laying mode and laid down on a field in the form of a swath. In the swath laying mode, the straw guide plates are moved into a position, in which the chaff is distributed over the operating width to both sides of the swath. In the swath laying mode, the chaff and the straw are distributed on the field over the operating width. In this case, the chaff is conveyed into the straw chopper by the blower of the cleaning assembly and the suction effect of the straw chopper. 
   Similar arrangements are known from the prospectuses “Deutz-Fahr Topliner 8XL,” Imprint 91 532 01 Printed in Germany 9906, “Case IH Cross-Flow,” Imprint CF80-D-BR-10/99, and New Holland CX Mähdrescher, Imprint Printed in Italy——01/09—Satiz Srl (Turin)—Cod. N. 12003/BR/D00. In these arrangements, the straw is either conveyed through the straw chopper, chopped and distributed over the operating width or conveyed around the rear side of the straw chopper and laid down on the field in the form of swaths. The chaff is conveyed into the straw chopper by the blowers of the chaff spreaders (Deutz-Fahr), impeller blower chaff spreaders (Case IH) or hydraulically driven radial blowers (New Holland). Since the straw chopper also operates in the swath laying mode, the chaff is distributed over the operating width and the straw can be harvested without a chaff fraction. 
   One disadvantage of the combine proposed in EP 0 727 135 A can be seen in the fact that a broad distribution of the chaff is not possible in the swath laying mode. Although the embodiments disclosed in the two above-cited WO publications are able to operate in several modes due to the utilization of separate chaff spreaders, the chaff spreaders are relatively expensive and heavy. In the embodiment according to DE 100 64 356 A and the cited prospectuses, chaff spreaders are not required because this function is fulfilled by the straw chopper. However, problems in conveying the chaff can be expected in the embodiment according to DE 100 64 356 A because the chaff is exclusively conveyed into the straw chopper by the blower of the cleaning assembly and the suction effect of the straw chopper. In the embodiments proposed in the aforementioned prospectuses and in EP 0 727 135 A, the chaff is conveyed by blowers that usually operate with a relatively low degree of efficiency. The embodiments according to DE 100 64 356 A and the aforementioned prospectuses only allow a broad distribution of the chaff. However, it is also desirable to incorporate the chaff into the straw swath in certain applications. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention of providing an improved conveying assembly for conveying chaff to a straw chopper. 
   In contrast to the pneumatic conveying assemblies used in the state of the art, the invention proposes to utilize a conveying assembly that mechanically feeds the second crop residue stream from the cleaning assembly to the straw chopper. The surface of the conveying assembly mechanically acts upon the particles of the crop residue stream. 
   This makes it possible to reliably and easily convey the second crop residue stream into the straw chopper in an energy-saving fashion. 
   The conveying assembly preferably extends between the outlet side of the cleaning assembly and the inlet of the straw chopper. 
   For example, the conveying assembly may consist of a vibrating bottom plate that carries out an oscillating back and forward movement under the influence of a suitable drive, e.g., as is common practice in the return bottom plates of combines. The surface of the vibrating bottom plate may be smooth, roughened or provided with steps or sawtooth-like elevations. It would also be conceivable to utilize any other continuous mechanical conveyor that does not operate pneumatically, e.g., a bucket conveyor, a paddle conveyor, a chain conveyor, a belt conveyor, a roll-type conveyor and/or a screw conveyor. 
   The laying down of the second crop residue stream may be controlled with several straw guide plates that are arranged laterally adjacent to one another and situated downstream of the straw chopper outlet. They are able to lay down the crop residues from the straw chopper in a swath or to distribute the crop residues over approximately the operating width of the cutting mechanism of the combine. In a swath laying mode, they are also able to deflect the second crop residue stream outward to such a degree that it is laid down laterally adjacent to the swath. Consequently, the straw can be received in a baling press or the like without a chaff fraction and then conveyed to further processing. 
   As already described in subsequently published DE 102 49 257 A, the disclosure of which is incorporated into the present application by reference, an ejecting drum may be provided between the outlet of the separating assembly and the inlet of the straw chopper in order to improve the transport of the first crop residue stream. 
   The aforementioned publication also proposes a movable straw guide element that makes it possible to easily change over between the swath laying mode and the chopping mode. In the swath laying mode, the first crop residue stream preferably is conveyed along the rear side of the straw chopper. However, it would also be conceivable to convey this first crop residue stream laterally along the straw chopper. It is also possible to utilize the movable straw guide elements proposed in DE 102 19 895 A, the disclosure of which is incorporated into the present application by reference, in order to change over between the swath laying mode and the chopping mode. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a semi-schematic side view of a combine having a transversely extending straw chopper. 
       FIG. 2  is a side view of the vibrating bottom plate that conveys the chaff into the straw chopper in the combine illustrated in  FIG. 1 . 
       FIGS. 3   a  and  3   b  are schematic side and top views of the combine in a swath laying mode, wherein straw is laid down in a swath while the chaff is distributed over the operating width by means of the straw chopper. 
       FIGS. 4   a  and  4   b  are schematic side and top views of the combine in a swath laying mode, wherein the straw is laid down in a swath while the chaff is incorporated into the straw swath by the straw chopper. 
       FIGS. 5   a  and  5   b  are schematic side and top views of the combine in a straw chopping mode, wherein the straw and the chaff pass through the straw chopper and are distributed over the operating width. 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a self-propelled combine  10  with a supporting frame  12  that is supported on the ground and moved by means of driven front wheels and steerable rear wheels  14 . The wheels  14  are set in rotation by a not-shown driving means in order to move the combine  10  over a field to be harvested. A harvesting assembly in the form of a cutting mechanism  16  is connected to the front end region of the combine  10  in order to harvest the crop standing in a field and to upwardly and rearwardly feed the crop to threshing and separating means via a feeder house  18 . The threshing and separating means comprise a transversely arranged threshing cylinder  20  and a concave  21  associated therewith. The harvested crop is initially fed to the threshing cylinder and concave. However, it would also be conceivable to omit the transversely arranged threshing assembly  20  and  21  and utilize a rotary threshing and separating assembly that is axially arranged. In this respect, it is possible to use only one axial separator or two (or more) axial separators arranged adjacent to one another. The separating assembly could also consist of straw walkers or separating drums that are arranged downstream of a threshing assembly  20  and  21 . In the illustrated combine  10 , a stripping roll  23  and a fed beater  22  cooperate with a feed housing to feed the threshed crop from the threshing assembly  20  and  21  to an axial separator  24 . The axial separator  24  is driven on its rear side by a gear  80 . In the following description, all directions such as front, rear, above and underneath refer to the forward driving direction V of the combine  10 . 
   The grain and the chaff separated during the threshing process fall onto at least one screw conveyor  30  that feeds the grain and the chaff to a preparation bottom plate  33 . However, the grain and chaff emerging from the axial separator  24  fall onto a vibrating bottom plate  32  that conveys the grain and the chaff onto the preparation plate  33 . The preparation plate  33  conveys the grain and the chaff to a cleaning assembly  34  having sieves arranged therein, wherein a blower  36  is assigned to the cleaning assembly in order to promote the separation of the chaff from the grain. The clean grain is fed to a not-shown elevator by means of a clean grain auger  38 , and the elevator transports the grain into a grain tank  40 . A tailings auger  42  returns non-threshed crop parts to the threshing process by means of another not-shown elevator. The chaff is ejected on the rear side of the sieves onto a vibrating bottom plate  84  that carries out an oscillating movement. The cleaned grain can be unloaded from the grain tank  40  by means of an unloading system with transverse screw augers  44  and an unloading auger  46 . 
   The aforementioned systems are driven by an internal combustion engine  48  that is controlled by an operator from a driver cab  50 . The different threshing, conveying, cleaning and separating assemblies are situated within the supporting frame  12 . 
   A first crop residue stream that essentially comprises threshed crop residues (straw) is downwardly ejected from the axial separator  24  that serves as the separating assembly (or one of the other alternative separating assemblies mentioned above), through an outlet  64  on the underside of the rear end of the rearwardly closed axial separator  24 . The crop residues fall into a vertical ejection shaft, the front of which is defined by a front wall  62 . An ejection drum  66  with drivers  67  distributed over its circumference is arranged beneath the outlet  64 . The rear of the ejection drum  66  is enclosed by a rear wall  86 . The ejection drum  66  is set in rotation about its longitudinal axis that extends transverse to the driving direction by an assigned drive, namely in the counterclockwise direction in  FIG. 1 . A straw guide element  68  that can be pivoted in its entirety about the axis of rotation of the ejection drum  66  adjoins the front wall  62  at approximately half its height, namely underneath the axis of rotation of the ejection drum  66 . The straw guide element  68  can be pivoted about this axis between the swath laying position illustrated in  FIGS. 1 ,  3   a  and  4   a  and the chopping position illustrated in  FIG. 5   a.    
   A generally known straw chopper  70  is arranged in a housing  72  beneath and slightly to the rear of the ejection drum  66 . This straw chopper can be set in rotation (in the counterclockwise direction in the figures) about a horizontal axis that extends transverse to the driving direction by means of a suitable drive and said chopper comprises a cylindrical body with chopping knives suspended thereon in a pendulum fashion. These chopping knives cooperate with stationary knives arranged in the housing  72  in order to chop and distribute the crop residues on the field over approximately the cutting width of the cutting mechanism  16  by means of a straw distributing shroud  74  that is equipped with straw guide plates  82 . One part of the housing  72  extends above the straw chopper  70  in the form of a circular arc, namely from the front end of the straw distributing shroud  74  to a point that approximately lies above the axis of rotation of the straw chopper  70  as shown in  FIGS. 1 ,  3   a ,  4   a  and  5   a.    
   The straw guide element  68  is curved in a concave fashion (and in the shape of a circular arc) and concentrically surrounds the ejection drum  66  for an angle of approximately 45 degrees. The straw guide element is coupled to the supporting frame  12  of the combine  10  in a pivoted fashion on its outer ends in the transverse direction. In the swath laying position shown and  FIGS. 1 ,  3   a  and  4   a , the straw guide element  68  extends from the front wall  62  to a point that approximately lies above the axis of rotation of the straw chopper  70 . In this position, the straw guide element  68  conveys the threshed crop residues from the ejection drum  66  transversely rearward and downward beneath the ejection shroud  76 . The underside of the ejection shroud  76  is, just like the straw distributing shroud  74 , provided with straw guide plates  78  in order to define the width of the swath of crop residues being laid down. 
   The vibrating bottom plate  84  extends rearward and upward from the lower rear end of the cleaning assembly  34  to a chopper inlet  88  that is in the form of an opening between the lower end of the front wall  62  of the ejection shaft and the upper end of the housing  72  of the straw chopper  70 , wherein said opening extends over the width of the ejection shaft and the straw chopper  70 . According to  FIG. 2 , the vibrating bottom plate  84  is connected to a suitable drive, such as a cam, so that it carries out an oscillating back and forward movement along its longitudinal direction similar to the vibrating preparation plate  32 . This is indicated by the arrows  92 . The vibrating bottom plate  84  is provided with sawtooth-shaped steps  90  as shown in  FIG. 2  or another suitable surface structure. This causes the chaff and other chopped straw fractions which are delivered onto the vibrating bottom plate  84  from the rear end of the cleaning assembly  34  under the influence of the blower  36  and through gravitational force in the form of a second crop residue stream to travel rearward and upward on the vibrating bottom plate  84  until they are conveyed through the opening  88  and into the straw chopper  70 . 
   The straw chopper  70  also operates in the position of the guide plate  68  illustrated in  FIGS. 1 ,  3   a  and  4   a . In this case, the straw chopper conveys the chaff and the chopped straw fractions, wherein the conveying effect suffices for conveying the chaff and the chopped straw fractions along the straw guide plates  82  and for ejecting them behind the combine  10  onto the field. 
   The straw guide plates  82  of the straw distributing shroud  74  are coupled to the straw distributing shroud  74  such that they can be pivoted about axles  94  that extend transverse to their longitudinal axis and the crop conveying direction. The pivoting axles are approximately situated on the rear ends of the straw guide plates in the embodiment shown. The straw guide plates  82  can be adjusted manually or in a remote-controlled fashion from the driver cab  50 , namely by means of suitable actuators in the form of electric or hydraulic motors that, in particular, are controlled by suitable sensors that automatically ensure the desired width of distribution. The straw guide plates  82  can be moved in this fashion between the broad laying position shown in  FIG. 3   b  and the swath laying position shown in  FIG. 4   b.    
   In the broad laying position ( FIG. 3   b ), the rear ends of the straw guide plates  82  point outward and the two central straw guide plates  82  contact one another on their front ends such that the chaff is prevented from being conveyed into the swath and the chaff is distributed on both sides and outside the swath of straw laid down in the swath laying mode, namely over approximately the width of the cutting mechanism  16 . The arrows in  FIG. 3   b  indicate that the straw can be harvested without a chaff fraction. 
   In the swath laying position ( FIG. 4 ), the straw guide plates  82  extend in the forward driving direction V of the combine  10 . The chaff is blown into the straw swath in the form of a swath, the width of which approximately corresponds to the width of the straw swath, such that a swath consisting of a straw/chaff mixture is laid down as indicated in  FIGS. 4   a  and  4   b . The chaff could also be laid down beneath the straw swath by manually or mechanically pivoting the straw distributing shroud  74  downward about the horizontal axle that extends transverse to the forward driving direction V at its coupling point on the housing  72  of the straw chopper  70 . 
   In the swath laying mode, it would also be conceivable to move the straw guide plates  82  into a position, in which the chaff is distributed over the field. In this case, part of the chaff also is laid down underneath the straw swath analogous to the position illustrated in  FIG. 5   b.    
   In the chopping position, the straw guide element  68  is pivoted rearward (in the clockwise direction referred to  FIG. 1 ) about the axis of rotation of the ejector drum  66  as shown in  FIG. 5   a . This causes an opening to be formed between the front wall  62  and the front edge of the straw guide element  68 , wherein the crop residues are introduced into the straw chopper  70  through this opening. In this position, the straw guide element  68  extends the rear wall  86  downward and forward. If the straw guide element is in the swath laying position, the front wall  62 , in its region below the line at which the straw guide element  68  adjoins, could also be provided with guide skids  84  in order to introduce the crop residues into the straw chopper  70  in the most uniform fashion possible. The straw and the chaff are chopped in the straw chopper  70  and ejected transversely rearward and downward such that they are distributed on the field over the operating width of the cutting mechanism  16  as indicated by the arrows in  FIG. 5   b.    
   The straw guide element  68  can be moved between the swath laying position and the chopping position by means of a manually actuated mechanism or suitable motors that are preferably remote-controlled from the driver cabin  50 . It would be conceivable to provide buttons or menus that make it possible to simultaneously adjust the straw guide element  68  and the straw guide plates  82  such that any of the operating positions of the straw guide element  68  and the straw guide plates  82  which are illustrated in  FIGS. 3 ,  4  and  5  can be selected by pressing only one button or selecting only one operating mode on a screen. 
   Having described the illustrated 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.