Patent Publication Number: US-2023157212-A1

Title: Threshing Concave For A Combine Harvester

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This claims priority to DE Application No. 102021128494.5, titled Threshing Concave For A Combine Harvester, filed Nov 2, 2021, which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates generally to a threshing concave for a combine harvester. 
     BACKGROUND 
     Agricultural combine harvesters are large machines which harvest, thresh, separate and clean the agriculturally cultivated, grain-bearing crop. The resulting clean grain is stored in a grain tank arranged on the combine harvester. Usually, tangential threshing devices are used for threshing, which have a threshing concave and a threshing drum conveying the crop tangentially, or axial threshing devices conveying the crop axially with axial threshing rotors, which also cooperate with a threshing concave. The threshing concaves are composed of arcuate and transverse bars which leave gaps between them. The threshing concave surrounds the threshing drum over part of its circumference and with it encloses a gap through which the crop to be threshed is forced. While the crop is conveyed through the gap, the crop components (grain) separate out, fall through the gaps and are supplied to a cleaning device. Depending on the crop composition, the components can be separated out to varying levels, so it is useful to be able to adapt the threshing concaves to the respective crop. 
     Thus, for example, it may be useful to provide at the inlet to the threshing concave, as an additional threshing means, a crop processing device which can be moved, usually rotated, between an active and an inactive position in order to thresh the crop more or less aggressively at the inlet to the threshing concave. Reference is made for example to DE 1 130 641 A, DE 1 130 640 A, U.S. Pat. No. 1,334,910A, EP 2 036 425 A1 and DE 10 2014 224 780 A1. 
     Furthermore, various adjustable elements are proposed which are arranged downstream of the inlet to the threshing concave, such as finger rakes which can be moved between an active position, running approximately tangentially to the threshing drum, and an outwardly pivoted position (U.S. Pat. No. 2,457,259 A, FR 637 181 A, U.S. Pat. No. 4,875,891 A, FR 2 621 216 A1, DE 10 2009 047 287 A1), or de-awning plates which can be brought into a closed position between adjacent threshing bars so that the crop cannot pass between the threshing bars and hence is cleared of awns by the longer action of the threshing drum (DE 1 989 612 U). Usually, a mechanism is provided via which all elements can be moved jointly, either by hand or by means of an externally powered actuator which can be operated from the cab of the combine harvester by an operator or by an automatic system. The crop processing device at the inlet to the threshing drum is adjusted similarly, usually by hand or via an actuator. 
     For threshing concaves provided with both a deactivatable crop processing device arranged at the inlet, and also adjustable elements (arranged downstream of the inlet to the threshing concave), two actuation elements are required in the form of manually operable levers or similar, or in the form of actuators in the case of automatic or remote control, which entails a relatively great complexity. 
     SUMMARY 
     The disclosure concerns a threshing concave for a combine harvester, having a crop processing device which is arranged on the threshing concave and can be adjusted between an active and an inactive position, adjustable elements which are arranged downstream of the inlet to the threshing concave and can be adjusted between an active and an inactive position, and an adjustment mechanism for separate adjustment of the crop processing device and the adjustable elements. 
     The object on which the disclosure is based is to provide a threshing concave of the type cited initially for a combine harvester in which said problems do not arise or only arise to a reduced extent. 
     A threshing concave for a combine harvester is provided with a crop processing device which is arranged on the threshing concave and can be adjusted between an active and an inactive position, adjustable elements which are arranged downstream of the inlet to the threshing concave and can be adjusted between an active and an inactive position, and an adjustment mechanism for separate adjustment of the crop processing device and the adjustable elements. The adjustment mechanism comprises a movable adjustment element which is coupled to the crop processing device and to the adjustable elements. 
     In this way, by manual or actuator-induced adjustment only of the adjustment element, either by hand or via an actuator, both the crop processing device and also the adjustable elements can each be moved independently of one another between an active and an inactive position. Therefore, only a single actuating element is required. 
     It should be pointed out that the crop processing device and/or the adjustable element can be moved by the movable element of the adjustment mechanism not only between an active position and an inactive position, but in one possible embodiment can also be moved into one or more or any number of intermediate positions between the active and inactive position. Thus, the degree of effect of the adjustable element and/or the crop processing device may be varied in more than one step or steplessly, in each case independently of one another. Furthermore, the movable element of the adjustment mechanism could also move any arbitrary third, fourth etc. adjustable device of the threshing concave. 
     In particular, the adjustment element may be coupled to the crop processing device and the adjustable elements such that in a first position of the adjustment element, the crop processing device and the adjustable elements are in the active position, in a second position of the adjustment element, the adjustable elements are in the inactive position and the crop processing device is in the active position (or vice versa), and in a third position of the adjustment element, the crop processing device and the adjustable elements are in the inactive position. 
     The crop processing device may be a rotatable body arranged at the inlet to the threshing concave, with threshing elements in the form of protrusions arranged thereon. The adjustable elements could be de-awning plates or finger bars. 
     The adjustment element may be a rotatable disk provided with two curves which are each coupled via cams and coupling elements to the adjustable elements and the crop processing device. 
     The threshing concave may cooperate with a tangentially conveying threshing drum or an axially conveying axial threshing rotor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       An exemplary embodiment of the disclosure is explained with reference to the drawings. The drawings show: 
         FIG.  1   , a partially cut-away, side view of a combine harvester with a threshing concave, 
         FIG.  2   , a perspective view of the front region of the threshing concave from  FIG.  1    from below, 
         FIG.  3   , a view similar to  FIG.  2    with adjustment element in a first position, 
         FIG.  4   , a view similar to  FIG.  2    with adjustment element in a second position, and 
         FIG.  5   , a view similar to  FIG.  2    with adjustment element in a third position. 
     
    
    
     DETAILED DESCRIPTION 
       FIG.  1    shows a self-propelled combine harvester  10  with a frame  12  which rests on the ground via driven front and steerable rear wheels  14 ,  16  and is advanced thereby. The wheels  14  are set in rotation by drive means (not shown) in order to move the combine harvester  10  for example over a field to be harvested. 
     A crop processing device  18  in the form of a cutting unit is removably mounted in the front end region of the combine harvester  10 , in order during harvesting to harvest the crop in the form of cereals or other threshable grains from the field, and deliver it upward and rearward via a feeder house  20  to a multi-drum threshing gear which comprises a threshing drum  22 , a stripping drum  24 , an overshoot conveying drum  26 , a separating drum  28  and a discharge conveyor  30 , which are arranged one behind the other in the direction of travel V. Downstream of the discharge conveyor  30  is a straw walker  32 . The threshing drum  22  is surrounded by a threshing concave  34  in its lower and rear regions. A cover  35 , which is either closed or provided with openings, is arranged below the conveying drum  26 , while a fixed cover is provided above the conveying drum  26 , and a separating cage  36  with adjustable finger elements is arranged below the separating drum  28 . A separating grating  38  is arranged below the undershoot discharge conveyor  30 . 
     A front conveyor floor  40  is provided below the multi-drum threshing gear. A rear conveyor floor  42  is arranged below the straw walker  32 . The conveyor floors  40 ,  42  transport the mixture of grain, short straw and chaff from the threshing concave  34 , the separating cage  46 , the separating grating  38  and the straw walker  32 , to a cleaning device  46 . The grain cleaned by the cleaning device  46  is supplied by means of a grain auger  48  to an elevator (not shown) which conveys it to a grain tank  50 . A returns auger  52  returns unthreshed ears via a further elevator (not shown) to the threshing process. The chaff may be ejected at the rear of the sieve device by a rotating chaff distributor or is discharged via a straw chopper (not shown) arranged downstream of the straw walker  32 . The cleaned cereal from the grain tank  50  may be discharged via a discharge system with transverse augers  54  and an output conveyor  56 . 
     Said systems are driven by means of an internal combustion engine  58  and are controlled and operated by an operator from a driver&#39;s cab  60 . The various devices for threshing, conveying, cleaning and separating are situated inside the frame  12 . Outside the frame  12  is an outer shell which can be largely opened. In another embodiment, the threshing gear may also comprise only the threshing drum  22 , the stripping drum  24  and the discharge conveyor  30 , i.e., be designed as a conventional tangential threshing system without separating drum  28  and without conveying drum  26 , in which the discharge conveyor  30  directly follows the threshing drum  22 . All directional indications below, such as front, back, above and below, relate to the forward travel direction V of the combine harvester  10 . 
     Reference is now made to  FIGS.  2 - 5   . The threshing concave  34  itself is of conventional design and comprises two arcuate side cheeks  62  adapted to the radius of the threshing drum  22 , between which threshing bars  68  extend (in the front region of the threshing concave  34 ). Following the threshing bars  68  in the circumferential direction of the threshing drum  22  (i.e., in a rear region), the threshing concave  34  comprises further arcuate bars  64 , between which cage wires  76  are arranged which extend in the circumferential direction. Further cage wires  78  are also arranged between the threshing bars  68 . These are thinner than the cage wires  76  arranged in the rear region of the threshing concave  34 , but present in a greater number. 
     A crop processing device  84  is arranged in front of the threshing concave  34  in the flow direction of the crop. The crop processing device  84  comprises a body  66  extending between the side cheeks  62 , where it is mounted so as to be rotatable about its longitudinal axis. On the body  66 , threshing elements  80  are arranged which can be moved, by rotation of the body  66  about its longitudinal axis, between an active position (see  FIGS.  2 ,  3  and  4   ) in which they are in engagement with the crop and provide a certain threshing effect, and an inactive position ( FIG.  5   ) in which they are spaced from the crop. In particular, the crop processing device  84  may be configured in accordance with EP 2 036 425 A1 or DE 10 2014 224 780 A1, the disclosure of which is included by reference in the present documents. 
     Furthermore, in the front region of the threshing concave  34  in which the threshing bars  68  are present (said region being formed as an insert which is removable by means of a suitable mechanism  132 , cf. DE 10 2015 205 992 A1, the disclosure of which is included by reference in the present documents), adjustable elements  86  are provided which, in the exemplary embodiment illustrated, are configured as so-called de-awning plates  82 . The adjustable elements  86  (as evident in  FIGS.  3 - 5   ) are movable between an open position (shown in f  FIGS.  2 ,  4  and  5   ) and a closed position (shown in  FIG.  3   ). In the closed position, the de-awning plates  82  serve to prevent the passage of crop components (in particular grain) between the threshing bars  68 , so that the crop is processed more intensively in the front region of the threshing concave than when the de-awning plates  82  are opened and can only drop down between the cage wires  74  at the earliest in the rear region of the threshing concave  34 . The de-awning plates  82  are known in themselves (see DE 1 989 612 U) and in another embodiment could be replaced by adjustable finger bars as adjustable elements. 
     Accordingly, the threshing concave  34  comprises an adjustable crop processing device  84  and the adjustable elements  86 , which can be adjusted independently of one another between an active and an inactive position. As discussed above, the crop processing device  84  and the adjustable elements  86  have separate actuating means in the form of manually operated levers or actuators for adjustment. The present disclosure deals with an adjustment mechanism  92  which allows movement of both the crop processing device  84  and the adjustable elements  86  between an active and an inactive position, independently of one another, by means of a single adjustment element  88 . 
     The adjustment element  88 , configured as a cam disc  90 , is rotationally fixedly connected to a shaft  96  which extends orthogonally to the plane of the side cheeks  62 , is arranged centrally on the cam disc  90  and is mounted rotatably on a downwardly extended portion  94  of one of the side cheeks  62 . The shaft  96  and hence the adjustment element  88  can themselves be rotated about their longitudinal and rotational axis via said actuating means between two end positions, one of which is shown in  FIG.  3    and one in  FIG.  5   , while  FIG.  4    shows an intermediate position. 
     The cam disc  90  comprises two curved tracks  98 ,  100  configured as curved slots. 
     A first control cam  102 , which engages in and hence cooperates with the first curved track  98 , is attached to a first lever  104  which rests via a first bearing  106  on the lower region of the portion  94 . The angled first lever  104  is rotatably connected at its second end to a first push-rod  108  which in turn is rotatably coupled at its rear end to a forwardly extending first bracket  110 . The front ends of the adjustable elements  86  (de-awning plates  82 ) are rotatably hinge-mounted at the first bracket  110  and supported by their rear ends on transverse rods  112 . When the cam disc  90  is turned by the shaft  96 , accordingly the first lever  104  rotates about the first bearing  106  and moves the first push-rod  108  forward or backward, the movement of which is transferred to the first bracket  110  which moves the front ends of the adjustable elements  86  forward and upward or backward and downward, while the rear ends of the adjustable elements  86  rotate about the transverse rods  112 . Thus, the first curved track  98 , via the first control cam  102 , the first push-rod  108  and the first bracket  110 , moves the adjustable elements  86  between an active and an inactive position. The first curved track  98  is dimensioned such that the adjustable elements  86  are in the active (closed) position in the left end position of the adjustment element  88  (see  FIG.  3   ), while they are in the inactive (open) position in the middle position ( FIG.  4   ) and in the right end position. It is pointed out that the adjustable elements  86  could be also arranged in the middle region of the threshing concave  34  or are coupled to the threshing concave  34  via suitable coupling elements. For this, the adjustable elements  86  are connected rotationally fixedly to the respective transverse rods  112 , which in turn are mounted on the threshing concave  34  so as to be rotatable about their longitudinal axes. 
     A second control cam  116 , engaging in the second curved track  100 , is connected to a second lever  118 , which is rotatably supported via a second bearing  120  on the lower end of the portion  94 . The angled second lever  118  is rotatably connected at its other end to a second push-rod  122 , which in turn is coupled via a rotary bearing to a second bracket  124  attached to the body  66  of the crop processing device  84 . When the cam disc  90  is turned by the shaft  96 , accordingly the second lever  118  rotates about the second bearing  120  and moves the second push-rod  122  upward or downward, the movement of which is transmitted to the second bracket  124  which turns the body  66 . Thus, the curved track  100 , via the second control cam  116 , the second push-rod  118  and the second bracket  124 , moves the crop processing device  84  between an active and an inactive position. The curved track  100  is dimensioned such that the threshing elements  80  of the crop processing device  84  are in the active position in the left end position of the adjustment element  88  (see  FIG.  3   ) and in the middle position ( FIG.  4   ), while they are in the inactive position in the right end position. 
     As shown in  FIG.  3   , the shaft  96  is connected to a (single) actuating element  128  outside a side wall  126  of the frame  12  against which the side cheek  62  lies, said element comprising an actuator  130  which may be configured as an electric or hydraulic motor and allows rotation of the shaft  96  between the three rotary positions described (see  FIGS.  3 - 5   ). The shaft  96  thus extends through an opening in the side wall  126 . The actuator  130  may be actuated by means of an operator interface arranged in the driver&#39;s cab  60 , or by means of an automatic system which can operate the actuator  130  automatically according to properties of the crop detected by sensor(s). In another embodiment, the actuating element  128  is designed as a lever via which the shaft  96  can be turned manually between the described positions. In any case, the adjustment mechanism  92  according to the disclosure avoids the need for a second opening in the side wall  126  which would be required for passage of a second shaft for separate actuation of the adjustable elements  86  and the crop processing device  84 . The manual or actuator-controlled adjustment takes place outside the side wall  126 , which improves accessibility and accelerates any necessary manual adjustment. Also, the actuator  130  may be arranged outside the crop flow. 
     If the threshing concave  34  is arranged with adjustable spacing relative to the threshing drum  22  (see DE 10 2014 209 219 A1), the opening in the side wall  126  through which the shaft  96  extends may be configured as an oblong hole or slot, and the actuating element  128  may also be adjusted via a corresponding coupling to the threshing concave  34 . 
     The adjustment mechanism  92  described provides a first position of the adjustment element  88  (left end position shown in  FIG.  3   ) in which the crop processing device  84  and the adjustable elements  86  are in the active position, a second position of the adjustment element  88  (middle position shown in  FIG.  4   ) in which the adjustable elements  86  are in the inactive position and the crop processing device  84  is in the active position, and a third position of the adjustment element  88  (right end position shown in  FIG.  5   ) in which the crop processing device  84  and the adjustable elements  86  are in the inactive position. These three positions have proved suitable in practice since an active position of the adjustable elements  86  with an inactive crop processing device  84  is not required in practice. If this should nevertheless be the case, a modified form of the curved tracks  98 ,  100  could also allow this fourth position.