Abstract:
A large round baler includes a tensioning arm to which is mounted two cylindrical rolls between which extend a loop of each of a plurality of side-by-side, bale-forming belts. Two belt support pulleys are located in an upper region of the baling chamber above the tensioning arm, and alternate loops respectively of the plurality of bale-forming belts are respectively engaged about one and another of said two support pulleys, so as to form gaps between adjacent loops through which material entrapped in a given loop may exit.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention relates to a round bale press having a belt-tensioning device, cylindrical rolls rotatably mounted on the tensioning device, at least one belt pulley, and belts for a baling chamber which belts extend in at least one loop between said rolls and over the pulley.  
       BACKGROUND OF THE INVENTION  
       [0002]     Known large round balers (DE 199 41 604) include a variable baling chamber including a vertically swingable tensioning arm with two rolls, wherewith bale-forming belts can pass between the rolls and can be passed around a fixed belt pulley. Depending on the positioning of the tensioning arm, the size of the baling chamber can be varied.  
         [0003]     A problem which is associated with the known large baler is that the loop can collect some of the crop material which is being baled, and this can lead to jamming and the like.  
       SUMMARY OF THE INVENTION  
       [0004]     According to the present invention, there is provided an improved variable sized, baling chamber arrangement.  
         [0005]     An object of the invention is to provide a baling chamber arrangement including a tensioning arm carrying at least two cylindrical rolls, and at least two belt pulleys, and wherein a plurality of bale-forming belts are mounted in side-by-side relationship, with each belt extending in at least one loop between the two rolls and over one of the belt pulleys.  
         [0006]     In the described solution, a plurality of mutually displaced belt loops are provided, so that material which has become entrapped can exit laterally; instead of leading to jamming. The belt tensioning device can have any of a wide range of configurations. For example, it may comprise translationally movable rolls or the like. It is conceivable that two belts may be guided differently, i.e., each having a different guide path; however, it is also possible for the belts to be combined in groups, with one group passing around one roll and another group passing around the other roll.  
         [0007]     A swingable tensioning device, which, for example, has an arm disposed on each side of the baling chamber, which rotatably bears the ends of the rolls, is particularly advantageous, because its swinging movement causes the loops to be moved with respect to each other, and thereby the loop openings are caused to be periodically enlarged.  
         [0008]     The risk of jamming can also be reduced as a result of an arrangement wherein the gap between the rolls is changeable during the pressing process; e.g., if the rolls are swingably mounted on the tensioning device and their position can be adjusted by a lever system, a cable, a motor, or the like (see DE 42 15 308 C2).  
         [0009]     On the other hand, a single prescribed separation distance which is not changeable during operation can be brought to a minimum value and maintained, so that the risk of winding of spurious material is minimized due to a minimal gap in the baling chamber.  
         [0010]     Additional open spaces for lateral escape of entrapped crop material and/or for alternative configuration of the paths of the belts can be provided if a roll and/or a pulley extends over the width of only a few of the belts. This can be achieved, e.g., by employing rolls or pulleys which are mounted at only one end to the tensioning device or the chassis 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     In the drawings, an exemplary embodiment of the invention is illustrated, which is described in more detail below.  
         [0012]      FIG. 1  is a schematic right side view of a round baler having belts supported in a configuration in accordance with the invention.  
         [0013]      FIG. 2  is a perspective view of the belts shown in  FIG. 1 . 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0014]     A large round baler  10 , illustrated in  FIG. 1 , has a chassis  12  and a feed device  14  which conveys the crop materials which are to be baled, into a baling chamber  16  of variable size. The baling chamber  16 , which initially has an essentially triangular shape, is penetrated in the forward lower region by a so-called starter roll  18 , which assists in causing the accumulated material to be baled to rotate. In other embodiments of round balers, one may dispense with the starter roll  18 . The chassis  12  is supported by wheels  20  which can travel over the ground, and has side walls  22 , which laterally delimit the baling chamber  16 . At the forward side of the chassis  12 , a tow bar  24  is provided by which the round baler  10  can be connected to a towing vehicle. The feed device  14  is comprised of a tined reel  26  which picks up the crop materials from the ground and conveys them upward and rearward to a feeder device  27 , which introduces the crop material into the baling chamber  16 . The baling chamber  16  is surrounded on its periphery by a plurality of belts  28  which extend mutually parallel and each of which is relatively narrow. The belts  28  act upon and form the crop materials into a cylindrical bale. The belts  28  are guided over a plurality of pulleys  30 , which extend between, and have opposite ends mounted on, the side walls  22 . Two of the pulleys, namely pulleys  30 ′ and  30 ″ are of particular importance and will be described in more detail later. The belts  28  are moved by rotational driving of at least one of the pulleys  30 ,  30 ′ or  30 ″. A drive shaft  32  is provided for this purpose, which shaft can be connected to the towing vehicle. In addition, a tensioning device  34  is provided which in principle is essentially; known.  
         [0015]     The tensioning device  34  includes a respective tensioning arm  36  disposed on each side wall  22  and further includes a tensioning member  38  and rolls  40  and  42 .  
         [0016]     Whereas in this exemplary embodiment two tensioning arms  36  are provided, in other embodiments a single tensioning arm may suffice. Each tensioning arm  36  extends parallel to the side walls  22 . Normally, but not mandated, the tensioning arms  36  are disposed between the side walls  22 . In a forward end region of each tensioning arm  36 , the arm is swingably mounted on a forward, approximately mid-height region of the chassis  12 , or side walls  22 , by a bearing  48 . Each tensioning arm  36  extends horizontally to the rear to a point past the midpoint of the baling chamber  16 . Each tensioning arm  36  is provided with a connection  50  for the tensioning device  38 .  
         [0017]     In the exemplary embodiment shown, the tensioning device  38  is comprised of a spring  52  and tensile means  54 , and has the task of constantly urging the tensioning arm  36  into its lowermost position, in which the belts  28  are under minimum tension, with the tension increasing as the arm  36  moves upward toward the pulleys  30 ′ and  30 ″.  
         [0018]     The spring  52 , shown in  FIG. 1 , is a mechanical helical tension spring, but it may comprise hydraulic or pneumatic means, realized via, e.g., pressure reservoirs, valves, and the like. It is per se known in multifarious forms. The spring  52  is fixed in its upper end region in a bearing or support  56  on the corresponding side wall  22  of the chassis  12 .  
         [0019]     The tensile means  54  may be a chain or cable, one end of which is fixed to the lower end region of the spring  52 , and the other end of which is fixed to the connection  50 . The tensile means  54  between its ends is passed around a guide pulley  58  on the side walls  22 , whereby an upwardly directed movement of the tensioning arm  36  causes upward movement of the connection point  50  of the tensile means  54 , which, in turn, results in extension of the helical tension spring  52 .  
         [0020]     The rolls  40  and  42  are rotatably mounted on the end region of the tensioning arm  36 , which end region occupies the center of the baling chamber  16 , and said rolls extend over the entire width of the baling chamber  16 . They are mutually parallel and are spaced a small distance apart. The rolls  40  and  42  form a combination, and serve to keep the size of the baling chamber small, to provide high density in the bales being formed from the pressed crop. A roll  46  is somewhat distant from the other rolls and serves as a lower direction-change point for the belt  28  which comes from above and departs generally upwardly.  
         [0021]     The tensioning device  34  may have additional features which are per se known, and will not be described in detail. For example, these features may include a connection between the two tensioning arms  36  to cause them to move simultaneously, control means for causing the formation of soft centered bales, control means for the belt tension during expulsion of a bale from the baling chamber  16 , etc.  
         [0022]     The pulleys  30 ′ and  30 ″ are disposed generally above the set of rolls  40  and  42 , namely in the upper end region of the side walls  22  in the vicinity of a support which joins the walls  22 . The individual pulleys  30 ′ and  30 ″ serve as a direction change point for the belt  28  which comes from below and departs downwardly, wherewith the belt forms a loop around a given one of these pulleys. The two pulleys  30 ′ and  30 ″ are mutually parallel, and are separated by a small distance in the exemplary embodiment shown (in other embodiments, the separation between the pulleys  30 ′ and  30 ″ may be larger).  
         [0023]     Reference is now made to  FIG. 2 , from which one may see the course of the belts  28  over and between the rolls  40  and  42 , and over the pulleys  30 ′ and  30 ″. All other parts have been eliminated from this view, for the purposes of clear illustration.  
         [0024]     The principle of the invention is that, in contrast to the state of the art, not all of the belts pass over a single common pulley  30 , but rather, alternate belts pass over the individual pulleys  30 ′ and  30 ″, which leads to the displacement of the laterally neighboring belt elements.  
         [0025]     In a preferred exemplary embodiment, proceeding from right to left in  FIG. 2 , a first one of the endless belts  28  is passed between the rolls  40  and  42  and over the pulley  30 ′, and a sequentially next belt  28  is passed between the rolls  40  and  42  and over the pulley  30 ″. Then, the first path is availed, and then the second, and so on.  
         [0026]     As seen in particular from  FIG. 2 , there is in the opening between the rolls  40  and  42 , a gap which extends over the entire width of the baling chamber  16 . Beyond this gap, the individual loops diverge, whereby any crop material which may have been captured can escape or can be removed, or can be reduced in size, i.e., broken up, between the belts  28 , whereby the hazard of winding such material around the pulleys and rolls of the belt driving and guiding system is substantially reduced.  
         [0027]     In the exemplary embodiments which have been illustrated and described, it is assumed that the pulleys  30 ′ and  30 ″, and the rolls  40  and  42  extend over the entire width of the baling chamber  16 . This is not a mandatory requirement. Rather, pulleys and rolls supported at only one end may be used, and these pulleys and rolls may extend over only some but not all of the belts  28 .  
         [0028]     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.