Abstract:
A baler is formed with a bale chamber for compressing agricultural crop into bales, at least one knotter for knotting twine wrapped around a finished bale and a twine store having at least one magazine in which the twine rolls for supplying the knotter are accommodated with axes lying on a common line.

Description:
CROSS-REFERENCE TO A RELATED APPLICATION 
     The invention described and claimed hereinbelow is also described in German Patent Application DE 10 2012 002796.6, filed on Feb. 15, 2012. This German Patent Application, subject matter of which is incorporated herein by reference, provides the basis for a claim of priority of invention under 35 U.S.C. 119(a)-(d). 
     BACKGROUND OF THE INVENTION 
     The invention relates to a baler for compressing agricultural crop into bales. Balers are commonly found in substantially two designs, i.e., round balers and block balers. In round balers, continuously supplied crop is rolled up in a bale chamber to form a cylindrical bale and is compressed by the pressure of externally circulating belts. Block balers comprise a bale chamber in the form of an elongated channel, in which a baling ram is moved back and forth in order to press crop (which is fed in batches), onto a cuboid bale being formed. In both types of balers, once the bale has reached a desired target size, the bale must be stabilized by being wrapped with binding material (which is usually twine), in order to prevent the bale from falling apart after ejection from the bale chamber. 
     To ensure that harvesting proceeds rapidly and cost-effectively, all the twine required for a harvesting operation should be carried with the baler as the stockpile. Document WO 2007/136410 A2 makes known a block baler that carries the twine stockpile thereof in magazines disposed next to the pressing channel. The magazines each comprise a bottom plate, on which the twine rolls are located. The bottom plate is folded in the manner of an accordion in the longitudinal direction of the press and slanting downward to a side wall adjoining the pressing channel. The axes of the twine rolls each extend parallel to the folds of the bottom plate, in the transverse direction of the pressing channel. In this manner, the twine rolls are secured against sliding or rolling away during the harvesting operation. 
     To permit uninterrupted operation, the twine rolls must be connected to one another so that, as soon as one roll has been used up, the beginning of the next roll is drawn into the pressing channel. Errors that occur in the interconnection of the twine rolls can cause the twine to become stuck, and an operator must access the twine magazine and eliminate a knot that formed there before the harvesting operation can continue. 
     WO 2007/136410 A2 shows, in FIG. 4, a twine store having 15 twine rolls in three magazines. The twine rolls are interconnected across magazines via two or three rolls each to form six strands. Since a mirror-image, second twine store is provided on the other side of the baler, it is assumed that the twelve twine strands in all are provided to be tied around each bale in pairs, forming six loops. If the twine is not used up completely in a harvesting operation, twelve partially-used twine rolls remain, which the user must relocate in order to reload the device and connect the twine rolls in the pattern shown in FIG. 4. Alternatively, the user must refill the emptied compartments and connect the beginnings of the twine rolls loaded there to the ends of the partially-used twine rolls. The resultant criss-crossing paths of the twine strands to the knotters of the pressing channel, however, considerably increase the risk that the twine strands will become tangled in the storage area and that the supply of twine to the knotters will become disrupted. 
     The number of partially-used twine rolls that remains after a harvesting operation could be reduced by replacing the use of a double knotter. A double knotter connects two separately fed twine strands to form a loop, with the use of a single knotter, which is described in DE 10 2007 018 560 A1. The single knotter knots a single twine strand wrapped around the bale to form a loop. In order to supply such a single knotter, however, more than the two or three twine rolls shown in the aforementioned FIG. 4 would have to be interconnected. Hence, the problem remains that, during reloading, the twine rolls that are still present must be relocated, or the possibility of tangling occurring must be accepted. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the shortcomings of known arts, such as those mentioned above. 
     In an embodiment, the invention provides a baler that can be reloaded easily and safely, even if the twine supply was not used up completely in a previous harvesting operation. 
     The baler comprises a bale chamber for compressing agricultural crop into bales, at least one knotter for knotting twine wrapped around a finished bale and a twine store. The twine store accommodates twine rolls for supplying the knotter. In more detail, the twine store comprises at least one magazine, in which the twine rolls are accommodated with axes lying on a common line. These twine rolls can be easily interconnected, wherein the risk of connecting errors occurring (which could result in the twine becoming tangled) is minimized by interconnecting the rolls one after the other in the magazine. 
     The baler is preferably a block baler having an elongated pressing channel. 
     In such a block baler, the axis of the twine rolls preferably extends in the longitudinal direction of the pressing channel, thereby saving space. 
     If the twine rolls are supported such that these are displaceable along the axis, the space that becomes available when one twine roll is used up can be refilled by sliding forward the twine rolls that are still present. Accordingly, space that becomes available at one end of the magazine is filled with fresh twine rolls. Therefore, the twine rolls can always be interconnected one after the other, whereby the risk of various twine strands becoming tangled or, of errors occurring in the interconnection of the twine rolls, is minimized. 
     The magazine can advantageously comprise a trough in order to accommodate the twine rolls securely and in an easily displaced manner. 
     Double and single knotters also are possible for use as the knotters, in accordance with the invention. 
     The knotter is preferably a single knotter, thereby ensuring that a single strand of interconnected twine rolls suffices for supplying the knotter. 
     In order to supply a plurality of knotters, the twine store preferably comprises a plurality of magazines. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the invention will become apparent from the description of embodiments that follows, with reference to the attached figures, wherein: 
         FIG. 1  shows a schematic top view of a baler according to the invention; 
         FIG. 2  shows a side view of the baler; 
         FIG. 3  shows a view of a twine store of the baler from behind; 
         FIG. 4  shows a partially emptied magazine of the twine store; and 
         FIG. 5  shows the magazine during reloading. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following is a detailed description of example embodiments of the invention depicted in the accompanying drawing. The example embodiments are presented in such detail as to clearly communicate the invention and are designed to make such embodiments obvious to a person of ordinary skill in the art. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention, as defined by the appended claims. 
       FIG. 1  depicts a baler according to the invention in a highly schematic top view. Located in the pressing channel  1  are a baling ram  2  (which can move back and forth in the direction of travel), a bale  3  (which is being formed) and a finished bale  4 . The bales  3 ,  4  are each held together by a plurality of twine loops  5 , namely six loops in this case. 
     The same number of knotters  6  is disposed above the pressing channel, wherein, when the bale  3  has reached a target size, the knotters knot the twine strands wrapped around the bale to form a fixed loop  5 . Suitable knotters are described substantially in the technical literature and so there is no need to explain the design thereof here. Dedicated to each knotter  6  is a magazine  7  in one of two twine stores  8  arranged in a mirror image on either side of the baling ram. The magazine contains the twine required for the operation of the knotter  6 . 
     Each of the magazines  7  holds a plurality of twine rolls  9 , the longitudinal axes  21  of which are aligned parallel to the longitudinal direction of the pressing channel  1 . The twine rolls  9  are hollow, without a core. A front end of the twine roll  9   a  closest to the baling ram  2  is drawn out of the inner hollow space of this twine roll  9   a  and is fed via eyelets  10  or similar guide means to one of the knotters  6 . A back end, which is located on the outer side of this twine roll  9   a , is knotted with the front end drawn out of the hollow space of the twine roll  9   b  that follows in the direction of travel. The twine rolls lined up in the magazine  7  therefore form a single, interconnected strand of twine. This ensures uninterrupted operation of the baler until the twine roll  9   f  located furthest to the rear in the direction of travel is used up. 
     It should be clear to the reader that the number of six twine rolls  9  per magazine  7  (as shown) is simply presented for exemplary purposes, and that deviating numbers can result depending on the installation space available in the magazine  7  and on the dimensions of the twine rolls  9 . 
     Six magazines  7  are required in order to supply the six knotters  6  in all, each twine store  8  comprising three of these magazines. As shown in  FIG. 2 , the magazines  7  of a twine store  8  are disposed one above the other and above a wheel  11  of the baler. The arrangement of the twine rolls  9  is the same in every magazine. The twine roll  9   a  located furthest to the front in the direction of travel of the baler, i.e., the one on the left in  FIGS. 1 and 2 , is connected via eyelets  10  or the like to the particular assigned knotter  6 . The outer end thereof is knotted with the inner end of the twine roll  9   b  following in the direction of travel. 
       FIG. 3  shows the magazine  7  on the left as viewed from the rear of the baler. Three troughs  13  extend from an inner wall  12  facing the pressing channel. Each of the troughs accommodates the twine rolls  9  of a magazine. The troughs  13  can be oriented horizontally in the longitudinal direction of the vehicle. This ensures that vibrations occurring during operation do not cause directional motion of the rolls in the magazine  7 . 
     It also is feasible to secure the twine rolls  9  against possible shifting during operation, for example, via fingers  14  that engage from a cap  15  of the twine store  8  into the interior thereof and into intermediate spaces  16  (see  FIG. 2 ) between the twine rolls  9  accommodated therein. These fingers  14  secure the twine rolls  9  from moving along the troughs  13 , provided that the cap  15  is closed. Bit if the cap is swiveled upward about an axis  17  extending in the longitudinal direction of the baler to permit loading of the twine store  8 , the fingers  14  also are withdrawn from the intermediate spaces  16 . Consequently, a user can displace the twine rolls  9  in the troughs  13  if necessary. 
       FIG. 4  shows a side view of a magazine  7  after a harvesting operation. Of the rolls  9  that were originally loaded, the first three have been used up. The fourth, which is labeled as  9   d , has been started. One strand  18  of the twine extends freely through the empty front half of the magazine  7  to the eyelet  10 . Loading new twine rolls in this free region would obviously hinder the dispensing of twine from the roll  9   d.    
     The baler is easily operated further without unloading the twine rolls that are still present in that the twine rolls are shifted toward the front end of the magazine  7 , as shown in  FIG. 5 . A new twine roll  9   g  is loaded into the back half of the magazine, which is now free. The front end  19  is withdrawn from the inner hollow space of the roll and is connected to the back end  20  of the roll  9   f , which was already placed furthest to the rear. This procedure is repeated until the magazine  7  has been completely filled once more. Consequently, the baler is ready for a new harvesting operation. 
     The following list of reference signs of various elements mentioned above is included (as follows), for ease of explanation: 
     REFERENCE CHARACTERS 
     
         
           1  pressing channel 
           2  baling ram 
           3  bale 
           4  bale 
           5  twine loop 
           6  knotter 
           7  magazine 
           8  twine store 
           9  twine roll 
           10  eyelet 
           11  wheel 
           12  inner wall 
           13  trough 
           14  finger 
           15  cap 
           16  intermediate space 
           17  axis 
           18  strand 
           19  front end 
           20  back end 
           21  axis 
       
    
     As will be evident to persons skilled in the art, the foregoing detailed description and figures are presented as examples of the invention, and that variations are contemplated that do not depart from the fair scope of the teachings and descriptions set forth in this disclosure. The foregoing is not intended to limit what has been invented, except to the extent that the following claims so limit that.