Abstract:
A rotary conveyor being disposed above the straw walkers of a combine is provided with a rotating body and disappearing tines. The rotary conveyor is an undershot conveyor and is designed to more aggressively loosen threshed crop material passing over the straw walkers. The tines are eccentrically supported in bearings. The tines can move radially in through tines guides that are located in recessed regions of the rotating body. The recessed regions being parallel to the transverse axis of the rotating body.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
       
     The invention is directed to a rotary tine conveyor having a rotating body having a plurality of tines. The rotating body is provided with a substantially closed outer circumferential surface and recessed regions through which the tines project. The freely rotatable tines are eccentrically supported in bearings. The recessed regions are provided with tine guides through which the tines project. 
     2. Description of the Prior Art 
     Several methods are known for the loosening and distributing a threshed crop mat in a combine. One example comprises grasping the crop and distributing it with a rotary conveyor equipped with rigid fingers. The rotary conveyor being located above the straw walkers of a combine. Known combines employ conveyors equipped with tines that perform undershot conveying or conveyors equipped with toothed rails that perform overshot conveying. DE-OS-41 27 118 proposes a rapidly rotating crop processing arrangement in the form of a conveyor belt equipped with tines that should supplement a following transverse straw walker in tearing apart the mat of threshed crop material. 
     The transverse straw walker can also be replaced by a rotary conveyor with movable tines that are supported eccentrically in bearings, as is known from DE-PS-1 904 406. In all cases the straw is loosened more intensively and for a longer period of time for a thorough separation of the remaining kernels. Due to the tearing apart of the mat of the threshed crop material, heavier crop components such as grain can escape through the gaps thus created. 
     SUMMARY 
     It is an object of the present invention to provide a rotary conveyor which eliminates numerous projections which can carry along the crop, for example, stalks, that can wrap itself around the rotary conveyor which limits the conveying capacity and the crop material is treated very harshly. 
     The rotary conveyor of the present invention comprises a rotating body with at least one tine supported in bearings eccentrically to it which can move radially with respect to the rotating body. The rotating body is provided an outer circumferential surface and recessed regions offset radially towards the interior of the rotating body. These recessed regions extend parallel to the longitudinal centerline of the rotating body. Tine guides are arranged in these recessed regions. The danger of wrapping by the crop is reduced, since the surface of the rotary conveyor exhibits fewer projections. Between the recessed regions the outer circumferential surface of the rotating body is configured with a circular contour being curved and smooth. 
     In the radially inward position of the tines, the free end of the tines is located below the outer circumferential surface defined by the rotating body. That is, the tines are retracted behind the circumferential surface of the rotating body, so that on the side on which the conveyed crop is delivered by the rotary conveyor the crop is not carried along. Thereby the material is treated very gently. The creation of recessed regions offset radially inward eliminates a radially inward extension of the tine guides, which leads to a clear saving of material, if the tine guides must be replaced after severe wear or damage by the crop. 
     The surface of the rotating body is formed by at least one metallic cover that is curved in such a way that it forms the outer circumferential surface and the recessed regions. The edges of the metallic cover extending parallel to the longitudinal centerline are accommodated on the shadow side located in the direction of rotation of the drum conveyor of the recessed regions. This reduces the danger that the crop can snag. If the surface of the rotating body is provided with several metallic covers, only one cover needs to be removeable for maintenance or repair work. 
     The tines are freely supported in bearings on a stationary axle that is coupled to two stub shafts by support arms. One of the stub shafts is supported in bearings in the drive flange of the rotating body. The fastening of the drive flange to one of the end faces of the rotating body automatically centers the stub shaft. 
     The tines are arranged at distances to each other in the direction of the axis of rotation of the rotary conveyor, in particular in such a way that starting with the first tine each three tines form a group and successive tines are offset to each other by 120 degrees. The offset of successive tines may vary depending on the application and may, for example, conform to the width of the straw walkers when used in a combine. 
     The rotary conveyor is installed above the straw walkers in such a way that above each individual straw walker a group of three tines is positioned. 
     The tines are alternately extended and retracted during one rotation of the rotating body about its longitudinal centerline. In this way the tines are able to take up and deliver the crop to be conveyed, for example, performing undershot conveying above the straw walkers of a combine. 
     In order to further reduce the danger that crop to be conveyed wraps itself around the rotary conveyor, a sheet metal deflector can be positioned on the rotating body. Due to the submergence of the tines it is possible to maintain a very small gap between the sheet metal deflector and the surface of the rotating body, so that crop to be conveyed is deflected efficiently. The sheet metal deflector can extend over the entire length of the side of the rotating body or it may consist of strips that keep the crop away from the surface of the rotating body only between the tines. The sheet metal deflector may also be positioned so close to the drum, that it can also tear off stalks that adhere to the drum. 
     If the sheet metal deflector is supported in bearings so as to pivot on the frame of a harvesting vehicle, it may be folded back by material that possibly nevertheless adheres and actuate a switch which releases a warning signal. 
     The rotary conveyor can be arranged in such a way that it is able to transport crop material both in overshot and in undershot conveying. In overshot conveying, for example, above the mower beam of a combine, the advantages resulting from the elimination of projections, such as the tine guides, become equally apparent as during undershot conveying. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a semi-schematic side view of a combine having the rotary conveyor of the present invention. 
     FIG. 2 is a front cross sectional view of the rotary conveyor of the present invention. 
     FIG. 3 is a side cross sectional view taken along line  3 — 3  in FIG.  2 . 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows a harvesting machine  10  in the form of a combine with front driven and rear steerable wheels  12  or  14  and an operator&#39;s cab  16  from which it can be controlled by an operator. In place of a combine, the present invention could also be used on a stationary threshing machine, a pull combine, or the like. The operator&#39;s cab  16  is followed to the rear by a grain tank  18 , that can deliver crop deposited in it to the outside through a discharge pipe  20 . The grain tank  18  is supported on a frame  22 , in which crop supplied to it is separated into its large and small components in its path over a threshing cylinder drum  24 , a threshing concave  26  and a beater  28 . On the following straw walkers  30 , as well as on a grain pan  32  and sieves  34  further separation of the harvested crop is performed, where finally the threshed out grain is conveyed to the grain tank  18 , the large remaining crop components (straw) are deposited on the ground over the straw walkers  30  and light remaining crop components (chaff) are blown from the sieves  34  by means of a blower  36  out the rear of the combine and onto the ground. The standing crop is first harvested by a platform  40 . The harvested crop is conveyed by feederhouse  38  to the threshing cylinder  24  and concave  26 . 
     A rotary conveyor  42  is arranged above the straw walkers  30 . The rotary conveyor  42  rotates about a transverse axis to the direction of operation of the vehicle. The rotary conveyor  42  is used as supplementary separator and comprises a rotating body  44  and tines  84 . The tines  84  are made of metal or plastic. Next to the rotating body  44  a sheet metal deflector  8  is located. This deflector  8  maybe pivotally attached to the frame  22 . 
     As seen in FIG. 1, the rotary conveyor  42  rotates in the counterclockwise direction, so that undershot conveying is performed. For this purpose drive arrangements, not shown, are provided. For example, a belt pulley or a chain can be used to drive rotating body  44  which transmits a drive from a motor. 
     The rotary conveyor  42  is located preferably, but not absolutely, above the straw walkers  30  approximately halfway down the length of the straw walkers. This position can be varied vertically as well as horizontally by means of a corresponding guides. 
     Alternatively the rotary conveyor  42  could also be provided immediately downstream of the beater  28 . 
     The drive arrangement can be configured in various ways and contain, for example, a gearbox that can be varied in speed and/or direction of rotation, by means of which the rotational speed of the rotary conveyor  42  can be varied and its direction of rotation can be reversed. 
     In this way the rotary conveyor  42  can be driven so as to perform overshot as well as undershot conveying. Where, if necessary, the position of the tines  84  must be adjusted to conform. 
     The preceding description shows that the configuration of the rotary conveyor  42  corresponds essentially to the configuration of the central region of a screw conveyor of a harvesting platform. 
     According to FIG. 3, the rotary conveyor  42  comprises a rotating body  44 , whose surface is composed, in the present case, of three metallic covers  48 . The metallic covers  48  are curved in such a way that they are provided with an outer circumferential surface and recessed regions  46  offset radially inward from the outer circumferential surface. The recessed regions extend parallel to the axis of rotation of the drum-shaped rotary conveyor  42 . Tine guides  50 , consisting of plastic or metal, and corresponding openings  52  are located in regions  46 . The end edges of the metallic covers  48  that extend parallel to the axis of rotation disappear in the regions  46 . 
     End face walls  54  and  56  of the rotating body  44  are formed by disks  58  and  60 , one of which is provided with a bearing flange  62  that is fastened at six hexagonal disposed locations to the disk  58  by means of screws  64 . The disks  58  and  60  are spotwelded to the inner side of two metallic covers  48  of the rotating body  44  and contain depressions on the side facing the interior of the rotating body  44 . The rotating body  44  is supported on stub shafts  68 . The right stub shaft  68  is connected to the bearing flange  62  and is provided with a keyway  70  for a gear. 
     The rotating body  44  contains a bearing arrangement that is arranged eccentrically and parallel to the axis of rotation of the rotating body  44  and that contains two stationary stub shafts  74 , two support arms  76  and  78 , and an axle  80 . On the axle  80  two-piece clamps  82  are fastened at intervals which can pivot about the axle. 
     The tines  84  are configured as straight-line, massive and equally long rods having a circular cross section. They are provided with a breaking point  86 . The tines  84  maybe arranged as trailing tines, that is trailing the direction of rotation, and, in principle, need not be as massive. The footings of the tines  84  are so configured that they fit into corresponding recesses in the clamps  82  and can be retained therein. 
     The tines  84  are arranged along the axle  80  in such a way that they offset at a fixed angle to each other, for example, 120 degrees and extend through the tine guides  50 . The tines  84  extend to differing lengths through the openings  52  and the tine guides  50  in the rotating body  44  beyond it to the outside. 
     The axle  80  is rigidly connected by means of the support arms  76  and  78  with the stub shafts  74 . The right stub shaft  74  is supported in bearings and free to rotate, in the bearing flange  62 . The left stub shaft  74  is rigidly fastened outside the rotating body  44 . Two roller bearings  4  and  6  allow for rotation of the rotating body  44  in a plane perpendicular to the longitudinal centerline  88 , the disks  58  and  60  rotate about the stationary stub shafts  74 . The axle  80  retains its position and the tines  84  are retracted and extended during a rotation of the rotating body  44  through the tine guides  50  that are laterally centered and located in the recessed regions  46 . If a tine  84  is in its radially inward position, then its free end is retracted below the outer circumferential surface of the region defined by the rotating body  44  that is not recessed. The path described by the free ends of the tines  84  is shown in FIG. 3 in dashed lines. 
     The tine guides  50  are arranged in the recessed regions  46  and are screwed or riveted to the metallic covers  48  in two places in the direction transverse to the longitudinal centerline  88  to either side of the openings  52 . The metallic covers  48  are connected to each other by screws  90  alongside each tine guide  50 . Two of the three metallic covers  48  are rigidly welded to the disks  58  and  60 . The third metallic cover  48  can be completely disassembled by removing the screws  90 . The screws  90  are accommodated on the shadow side that lies in the direction of rotation of the rotating body  44  in the recessed regions  46 . 
     In addition, to the creation of recessed regions for the tine guides  50  and the screws, the employment of several metallic covers  48  according to FIGS. 2 and 3 has the advantage that it considerably simplifies the accessibility for assembly and maintenance. In order to make possible, for example, to access the clamps  82 . It is only necessary to remove the screws of the metallic covers  48  which are not welded to the disks  58  and  60  in the recess in which the tine guide  50  is located. As is shown in FIG. 3 on the basis of two positions the metallic cover  48  is then spaced away from the circumferential surface. 
     Corresponding to FIG. 1 a sheet metal deflector  8  may be positioned on the rotating body  44  that is oriented in such a way that upon rotation of the rotating body  44  crop to be conveyed that has adhered to the rotating body  44  can be stripped off. 
     In an application of the rotary conveyor  42  in a combine the tines  84  may be arranged in such a way that they are located in groups of three tines  84  above an individual straw walker  30 , that is, in a five-straw walker machine fifteen tines are applied and in a six-straw walker machine eighteen tines  84  are applied as is shown in FIG.  2 . The three tines  84  located in each case ahead of the end face disks  54  and  56  of the rotating body  44  are spaced, in this example, at a smaller distance to each other than the remaining tines  84 . 
     The invention should not be limited by the above described embodiment, but should be limited solely by the claims that follow.