Abstract:
A crop discharge device for discharging crop from a harvesting machine, comprising a rotatatable rotor mounted in a housing having a movable a bottom. The bottom can be put into a reciprocating motion in order to convey the crop to be discharged to the crop discharge device. Chaff from a cleaning shoe is directed by an oscillating bottom to the bottom. The discharge device may comprise a straw chopper which discharges chaff and straw from the harvesting machine in the chopping mode.

Description:
FIELD OF THE INVENTION 
   The present invention is directed to a discharge device for discharging crops from a harvesting machine. The discharging device comprises a rotatable rotor mounted in a housing having a moving bottom. 
   BACKGROUND OF THE INVENTION 
   In many combines, the chaff is discharged through separate chaff distributors. The chaff distributors are relatively large blowers, which are usually driven hydraulically. Therefore, they are relatively costly and heavy. Thus, it can be advantageous to discharge the chaff through an existing straw chopper. 
   In DE 44 31 802 A it is proposed to feed the chaff through a back and forth moving inlet bottom of a horizontal conveyor screw, which feeds the chaff together with the straw to one or two straw choppers with vertical rotational axes. 
   In the publications DE 102 56 744 A and DE 103 03 503 A published later, it is proposed to convey the chaff by means of an oscillating base from the cleaning section to the inlet of the straw chopper, in DE 103 03 503 A with the simultaneous action of a rotating conveyor. 
   In U.S. Pat. No. 3,669,123 A, a combine is described, for which the chaff is fed by a slide connected to the cleaning shoe to the bottom of a straw chopper housing. The cleaning shoe shakes the slide. The straw chopper is located above the inlet for the chaff. The chaff is discharged by the air stream generated by the straw chopper. 
   According to U.S. Pat. No. 5,232,405 A, a conveyor belt is used for transporting the chaff from the cleaning section into a straw chopper. 
   In EP 0 958 727 A, it is proposed to transport the chaff released by the cleaning section through a cross auger initially outwards transverse to the direction of travel. Two partial streams are produced on both sides of the combine, which are transported backwards through additional augers and fed in the axial direction to a straw chopper with a horizontal rotational axis that is transverse to the direction of travel. 
   The above mentioned references disclose a mechanical feed of the chaff into the straw chopper. The chaff is introduced into the straw stream at the end of the conveyor by the force of gravity (DE 44 31 802 A, U.S. Pat. No. 5,232,405 A, DE 102 56 744 A), by a rotating conveyor (DE 103 03 503 A, EP 0 958 727 A), or by the suction effect of the straw chopper (U.S. Pat. No. 3,669,123 A). Here, transfer problems can occur. 
   In DE 36 20 747 A, a combine with a straw chopper is described. The straw released by the straw shakers slides along a straw guiding plate into the straw chopper. The straw guiding plate is set into a vibrating motion in order to improve conveyance. Here, likewise only one element is set in vibration, which transports the crop residue into the straw chopper, so that conveyance problems can occur with the transfer into the straw chopper. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide an improved discharge device for a harvesting machine, for which the disadvantages mentioned above occur not at all or only to a limited degree. 
   It is proposed to set the bottom of the housing of the discharge device in a vibrating motion. Through this oscillating or vibrating motion, which is preferably oriented tangential to the rotational direction of the rotor of the discharge device (or its circular envelope) and thus corresponds to the supply direction of the discharged goods, the goods are successively fed to the rotor and grasped by it. Because not only the supply device, but also the housing bottom moves, there is no risk of transfer problems at the inlet of the discharge device. 
   The feed of the discharged goods can be improved by a step like shoulder in the bottom, wherein the shoulder moves like a piston and feeds the goods successively to the rotor. 
   The invention is particularly suitable for combines, for which a straw chopper is usually used as a discharge device. However, it is also conceivable to set the bottom of a blower or some other conveyor used for discharge of crops into oscillations in the way according to the invention. For such embodiments, a straw chopper of arbitrary configuration can be arranged in front of or behind the discharge device, e.g., a number of chopping blades interacting with a separating rotor, a conventional straw chopper with a rotor and oscillating blades which interact with counter blades, or rotating arms whose ends are provided with blades. 
   Especially advantageous is the use of the invention in combines, for which a first crop residue stream (straw) is fed to the discharge device from a separating device and a second crop residue stream (chaff) from a cleaning device. The second crop residue stream is fed to the housing bottom, while the first crop residue stream is usually fed in a known way to the rotor from above. 
   For transporting the second crop residue stream, an arbitrary conveyor can be provided, e.g., a belt or bowl conveyor. However, an oscillating bottom conveyor, which is set into an oscillating motion, like the housing bottom, has proven to be especially advantageous. This oscillating motion can be taken from the existing oscillating motion of the cleaning device. 
   The bottom of the discharge device can be connected rigidly to the oscillating bottom. However, because the housing bottom should move as little as possible in the vertical (or radial to the rotor) direction in order to maintain a constant distance between the housing bottom and the rotor for the purpose of optimum conveyance of goods, a relatively small vertical motion, which can lead to a non optimal conveyance, is also produced in the region of the oscillating bottom in the vicinity of the housing bottom. Therefore, it is preferred to connect the housing bottom to the oscillating bottom through a joint or a hinge. Therefore, the latter can move sufficiently in the vertical direction, which improves its conveyance ability. 
   The present invention can be used especially meaningfully on a combine, for which the first crop residue stream (i.e., the straw) is fed to the straw chopper in a chopping mode and led past the straw chopper, usually to the back side of the straw chopper, in a long stalk straw deposition mode. The second crop residue stream is fed to the straw chopper in the chopping mode and distributed together with the first crop residue stream approximately over the width of the cutting apparatus over the field. In the long stalk straw deposition mode, the second crop residue stream is likewise fed to the straw chopper in order to provide it with sufficient velocity to leave the combine without any problems. The second crop residue stream can be deposited in a swath in the long stalk straw deposition mode. It is introduced into the straw swath or laid underneath. Therefore, the chaff can be taken up and used together with the straw. In another (especially selectively feasible) mode, the second crop residue stream is distributed over the field after passage through the straw chopper in the long stalk straw deposition mode, wherein chaff is optionally not included in the area of the straw swath. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic side view of a combine with an axial separator and a straw chopper, which is used for discharging the chaff. 
       FIG. 2  is an enlarged side view of the conveyor device, which transports the chaff into the straw chopper in the combine from  FIG. 1 . 
       FIG. 3  is a side view of another embodiment of the conveyor device from  FIG. 2 . 
       FIG. 4  is a side view of another embodiment of the conveyor device from  FIG. 2 . 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a self propelled combine  10  with a chassis  12 . The chassis  12  is supported by front driving wheels and rear steering wheels  14 . The wheels  14  are driven by means of a drive means, not shown, in order to move the combine  10  over a field to be harvested. The front of the combine  10  is provided with a harvesting assembly in the form of a cutting platform  16  to harvest the crop from the field and to feed it upwards and backwards through a feeder house  18  to threshing and separating assemblies. The threshing and separating assemblies include a transverse threshing cylinder  20  and associated concave  21  to which the harvested crop is first fed. However, it is also conceivable to leave out the transverse threshing cylinder  20  and to use an axial threshing assembly that is integral with an axial separator. Downstream from the threshing cylinder  20  and concave  21  is an axial separator  24 . The axial separator can be arranged as a single axial separator or two (or more) axial separators arranged one next to the other. Also, the use of straw walkers or separating drums arranged downstream of the threshing drum as separating assembly is also conceivable. Together with a supply housing, a stripping roller  23  and a feed beater  22  direct the threshed crops from the threshing cylinder  20  and concave  21  to the axial separator  24 . The axial separator  24  is driven on its rear side by a gear  80 . All indications of direction, such as front, behind, above, and beneath, refer to the direction of forward travel V of the combine  10 . 
   Grain and chaff, which are separated during the threshing process, fall onto at least one screw conveyor  30 , which feeds both to a preparation pan  33 . In contrast, grain and chaff, which are discharged from the axial separator  24 , fall onto a grain pan  32 , which leads the grain and chaff to the preparation pan  33 . The preparation pan  33  leads the grain and chaff to a cleaning shoe  34  having sieves  35 . A blower  36  directs an air blast upwardly through the sieves  35  in order to separate the chaff from the grain. Cleaned grain is fed by means of a clean grain auger  38  to an elevator, not shown, which lifts the cleaned grain into a grain tank  40 . A tailings auger  42  sends non threshed crop portions through another elevator, not shown, back into the threshing process. The chaff is discharged on the rear side of the cleaning shoe  34  onto an oscillating floor  84 , which is described in more detail below. The cleaned grain can be unloaded from the grain tank  40  by an unloading system comprising cross augers  44  and an unloading auger  46 . 
   The mentioned systems are driven by means of an internal combustion engine  48 , which is controlled by an operator from a cab  50 . The different devices for threshing, transporting, cleaning, and separating are located within the chassis  12 . 
   From the axial separator  24 , which is used as a separating device (or one of the other alternative separating devices mentioned above), a first crop residue stream, which essentially consists of threshed crop residue (straw), is discharged downwards through an outlet  64  at the bottom rear end of the axial separator  24 , which is closed at the back. Through the effects of centrifugal force and the force of gravity, the crop residue falls into a vertical discharge shaft, which is limited at the front by a front wall  62 . Beneath the outlet  64  there is a discharge drum  66 , around whose circumference carriers  67  are distributed. Towards the rear, the discharge drum  66  is enclosed by a rear wall  86 . The discharge drum  66  is set in rotation about its longitudinal axis by a drive in a clockwise direction in  FIG. 1 . The discharge drum  66  extends perpendicular to the direction of travel. A straw guiding element  68 , which can pivot about the rotational axis of the discharge drum  66 , contacts the front wall  62 , approximately beneath the rotational axis of the discharge drum  66 . The straw guiding element  68  can pivot about the rotational axis of the discharge drum  66  between the long stalk straw deposition position shown in  FIG. 1  and a chopping position not shown in the figures. 
   Beneath and slightly behind the discharge drum  66  is a straw chopper  70  housed in housing  72 . The straw chopper  70  acts as a discharge device which is set in rotation about a horizontal axis running perpendicular to the direction of travel (in the counterclockwise direction in the figures) by a drive. It includes a cylindrical rotor with chopping blades  73 , which are mounted so that they can pivot on the rotor and which interact with stationary counter blades  75  arranged in the housing  72  to chop the crop residue. The chopped crop residue is distributed by a straw distributor chute  74  arranged downstream from the straw chopper  70 . The straw distributor chute  74  is equipped with straw guiding plates  82 . The straw guiding plates  82  attempt to distribute the crop residue over the cutting width of the combine  10  onto the field. The rotor can also be provided with elements for air agitation. A top part of the housing  72  extends above the rotational axis of the straw chopper  70  from the front end of the straw distributor chute  74  like a circular arc approximately up to a point above the rotational axis of the straw chopper  70 . A front part of the housing  72  runs downwards between the contact point of the straw guiding element  68  to the front wall  62  and the front side of the straw chopper  70  approximately vertical. 
   The straw guiding element  68  is concave like a circular arc and encloses the discharge drum  66  by an angle of approximately 45° concentrically. It is hinged on its outer end in the transverse direction so that it can pivot on the chassis  12  of the combine  10 . The straw guiding element  68  extends from the front wall  62  to approximately over the rotational axis of the straw chopper  70  in the long stalk straw deposition position reproduced in  FIG. 1 . In this position, the straw guiding element  68  acts so that the threshed crop residue, i.e., the first crop stream, is delivered by the discharge drum  66  beyond a discharge chute  76  diagonally backwards and downwards. The discharge chute  76  is provided on its bottom side with straw guiding plates  78  in order to define the width of the swath, in which the crop residue is laid. 
   The straw chopper  70  is set in rotation in the position of the guiding plate  68 , as shown in  FIG. 1 . It exerts a conveyance effect on the chaff and the short straw portion fed to it through the oscillating bottom  84 , which is therefore sufficient to convey the latter along the straw guiding plate  82  and to push it onto the field behind the combine  10 . As indicated in  FIGS. 2–4 , the first crop stream leads into the straw chopper  70 , when the straw guiding element  68  is pivoted backwards. 
   The straw guiding plates  82  of the straw distributor chute  74  are hinged to the straw distributor chute  74  so that they can pivot about axes extending perpendicular to their longitudinal axes and the direction of flow of the goods. In this way, the straw guiding plates  82  can move between a broad deposition position and a swath deposition position. 
   In the chopping position, the straw guiding element  68  pivots backwards about the rotational axis of the discharge drum  66  (in the counterclockwise direction with reference to  FIG. 1 ). Therefore, an opening is unblocked between the front wall  62  and the front edge of the straw guiding element  68 , through which the first crop residue stream is led into the straw chopper  70 . In the straw chopper  70 , the straw is chopped and discharged together with the chaff diagonally backwards and downwards and distributed over the working width of the cutting apparatus  16  over the field. 
   The oscillating bottom  84  extends from the rear, lower end of the cleaning shoe  34  diagonally backwards and slightly downwards up to beneath the straw chopper  70 . There, it joins a bottom  94  of the housing  72  of the straw chopper  70 . The oscillating bottom  84  is coupled mechanically to the cleaning shoe  34 . The latter is set into a shaking motion with horizontal and vertical components through suitable drives, e.g., cams, similar to the grain pan  32 , in a known way. The oscillating bottom  84  driven by the cleaning shoe  34  and moving with this device thus forms a bottom  94  of the housing  72  of the straw chopper  70 , which bottom oscillates in the vertical and horizontal direction, wherein the bottom  94  can be produced as one part with the oscillating bottom  84  or as a separate element. 
   The arrangement and support of the oscillating bottom  84  are shown in more detail in  FIG. 2 . Near its front end, it is supported on the frame  12  of the combine  10  by an oscillating rocker  88  inclined slightly forward, but essentially vertical. Underneath the straw chopper  70 , it is attached to the frame of the combine  10  by a second oscillating rocker  90 . The oscillating rockers  90  are each supported on the frame  12  and the oscillating bottom  84  so that they can pivot on axes running horizontal and perpendicular to the direction of forward travel. 
   Because the oscillating bottom  84  is provided on its top side with saw tooth like steps  92  or another suitable surface structure and completes an oscillating motion, the chaff and other short stalk straw portions, which are discharged as the second crop residue stream from the cleaning shoe  34  to its rear end through the effect of the blower  36  and through the force of gravity on the oscillating bottom  84 , travel backwards on the oscillating bottom  84 . 
   The steps  92  end shortly before the straw chopper  70 . The bottom  94  of the housing  72  of the straw chopper  70  may be rigidly connected to the oscillating bottom  84  and moving back and forth with this bottom creates a successive feeding of the second crop residue stream to the straw chopper. Because the bottom  94  should move as little as possible in the vertical direction, and because otherwise the distance between the circular envelope of the chopping blades  73  and the bottom  94  would change, the second oscillating rocker  90  is arranged as vertical as possible. 
   In  FIG. 3 , a second embodiment of the invention is shown. It comprises the oscillating bottom  84 , which is provided with saw tooth like steps  92  and is supported on a first oscillating rocker  88  and a second oscillating rocker  90 , and ends before the straw chopper  70 . The bottom  94  of the housing  72  of the straw chopper  70  is configured as a separate element and is connected by a joint  96  in the form of a hinge with a pivoting axis oriented horizontal and perpendicular to the direction of forward travel to the oscillating bottom  84 . In the vicinity of its rear end, the bottom is connected by a third oscillating rocker  98  to the frame  12 . The vertical arrangement of the third oscillating rocker  98  and the joint  96  enable a nearly exclusively horizontal motion of the bottom  94  and a constant distance to the circular envelope of the straw chopper  70 . One advantage of this embodiment is that the second oscillating rocker  90  does not have to be arranged exactly vertical, so that the oscillating bottom  84  can also exhibit a vertical motion component over its entire length, which improves its conveyance effect. 
   The embodiment illustrated in  FIG. 4  differs from the previously illustrated embodiments essentially in that the top side of the bottom  94  is not smooth. It is provided in the front, upstream region with smaller steps  102 , which correspond to the steps  92  of the shaking bottom  84 . Directly in front of the contact point with the circular envelope of the chopping blades  73 , on the bottom  94  there is a larger shoulder  100 , which is inclined backwards, has a bevel facing the straw chopper  20  [sic;  70 ], whose shape is approximately adapted to this circular envelope. While the steps  102  simplify the transport of the second crop residue stream, the step  100  acts like a piston, which presses the material successively into the active region of the straw chopper  70 . Therefore, one achieves an active and improved conveyance of the crop stream into the straw chopper  70 . 
   Having described the illustrated embodiments, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.