Abstract:
A round baler has an unloading apparatus downstream of a bale chamber provided with movable carrying elements, for example rollers, belts, etc., so that a round bale discharged in rotating motion from the bale chamber is able to maintain its spin and twine wound onto it does not fall off again. To prevent the rotary motion of the round bale from being slowed or even terminated upon transfer to the unloading apparatus, stationary portions of a superstructure of the round baler, for example, a cross-stay serving as an axle, are covered by a movable cover.

Description:
FIELD OF THE INVENTION 
   The invention relates to a round baler comprising a superstructure, a bale chamber and a thereto adjoining unloading apparatus having at least one carrying element between the bale chamber and a ground surface, which carrying element permits a rolling motion of the round bale. 
   BACKGROUND OF THE INVENTION 
   Whenever a round bale is unloaded from the bale chamber of a round baler, the problem of controlling its motion always presents itself. If the round bale falls to roll far enough away from the round baler, the discharge gate cannot be lowered and the bale chamber cannot be closed. If the round bale has too much momentum, it rolls uncontrollably onwards and down a slope, for example, it is slowed too much upon discharge from the bale chamber, it remains stuck on an axle or other cross-stays and does not roll down the ramp, or its direction of rotation reverses and twine which is wound thereon falls off from the down-rolling round bale. 
   U.S. Pat. No. 4,683,815 A discloses a round baler having a ramp, on whose top side driven conveyor chains operate which transport the round bale securely away from the bale chamber. 
   From round balers of the company WELGER, it is additionally known to provide a vertically pivotable ramp at the outlet of the bale chamber and behind an axle which is provided with transversely disposed rollers and is thus intended to maintain the “spin” of the emerging round bale, so that the twine does not fall off. This effect only occurs, however, if the spin is still present as the bale is discharged. 
   The problem on which the invention is founded lies in the perception that there is no solution which prevents the twine from falling off due to the inversely rolling round bale and ensures a secure discharge of the round bale. 
   SUMMARY OF THE INVENTION 
   According to the present invention, there is provided a large round baler having a bale unloading apparatus constructed for overcoming the aforementioned drawbacks of known bale unloading apparatuses. 
   An object of the invention is to provide a bale unloading apparatus having at least one moveable element which moves so as not to impede the rolling motion imparted to a bale being discharged from the bale chamber of the baler. 
   In this way, the round bale which is still rotating upon discharge from the bale chamber does not come into contact with stationary parts of the superstructure, is not therefore slowed and maintains its spin, which is counter-directed to an unrolling of the twine. The relevant part of the superstructure can be the axle for the running wheels, a stay, guide plates for the net, hydraulic components and the like, which could exert a slowing effect upon the round bale in the event of contact. However, other fixed parts, for example of a binding apparatus, of the bale chamber, of the unloading apparatus, etc., which do not form part of the superstructure could also be covered. As defined in the dependent patent claims, the cover can also be very differently configured, the essential point being that the motion of the cover maintains the motion of the round bale. The motion could both be derived from the motion of the round bale and be actively generated, for example by a motor or a drive connection to driven parts of the round baler. Moreover, the motion of the cover could be controlled in order to generate the optimal rotation speed and, possibly, the direction of rotation of the round bale. 
   Since the side parts of the round baler are constantly connected by relatively large transverse-running stays, of which, according to function, the axle for the running wheels also forms part, there is always the danger there that the round bale makes contact and is slowed. Although rollers—generally of a small diameter—could be fitted on or around the cross-stay, the use of a large-diameter tube, which receives the cross-stay or the axle within it, appears simpler and more effective. This tube could consist of metal as well as of plastic and would preferably be smooth. 
   The tube is simple to fit if it is divided at least once in its longitudinal direction and can be securely rejoined. The closure can be made by collars, screws or the like. On the other hand, the tube could consist of a plurality of arc segments which are screwed or otherwise fastened onto annular brackets. 
   The mounting of the tube on plain or roller bearings ensures that no slowing effect derives from the tube itself. Depending on the length of the tube, a plurality of bearings can be provided or one or more long rollers or shafts can even be provided between the cross-stay and the inner side of the tube, which support the tube in a low-friction manner. 
   The spin of the round bale, i.e. its originally inherent rotary motion, is also maintained en route to being deposited on the ground, if it can continue rolling, for example on rollers. Rollers can be very stably configured and can be mounted for free rotation, are low in maintenance and cost-effective. 
   In usage conditions in which short crop, for example crumbling straw, can be expected, which could block clearances between adjacent rollers, it is sensible to use a substantially closed conveyor surface as the carrying element, for example a continuous belt, or a belt whose ends are connected to one another. Such a belt can be configured as wide as the round bale or, indeed, narrower, as long as it is ensured that the round bale can continue to rotate and cannot lean noticeably against stationary parts. The belt can be closed over the whole of its surface, or even perforated, smooth or profiled, and a tensioning apparatus can be provided, which keeps the strands always as straight as possible. Depending on the length of the belt, supporting rollers can also be used in between. In place of a belt, another traction means, for example a rod conveyor, can also be used. 
   The carrying element can also be configured as shown in U.S. Pat. No. 4,683,815, the conveyor chain which is shown there also being able to be replaced by a conveyor belt or rolling bodies—the essential aspect being merely that a fundamentally rigid ramp is provided which bears the carrying elements. As rolling bodies, hard-plastic as well as metal rollers could be used. The carrying elements which are provided in this way can be made in both driven and non-driven configuration. 
   On the one hand, the unloading apparatus having the carrying element(s) could be configured as an independent and complete unit, which is merely attached to the superstructure of the round baler, on the other hand, the carrying element of the unloading apparatus could also be wrapped around a roller situated on the superstructure or the bale chamber. A gap between the cover and the carrying elements. In which crop could gather, is thereby prevented. This has the effect, furthermore, that as the round bale is ejected, the carryig element is driven, i.e. moved, which transmits itself, in turn, to the round bale. Although such a drive mechanism is known from U.S. Pat. No. 3,974,632, in this case no round bale, but rather a stack of harvested crop, is discharged from a chamber. 
   In order to prevent damage to the unloading apparatus through contact with the ground, a stop is provided, so that the free end of its frame always keeps a distance to the ground. 
   The use of a, in particular, resilient bumper at the delivery end of the frame enables the round bale to be prevented from rolling back in the direction of the bale chamber. The resilience makes it possible to roll the round bale gradually onto the ground from the ends of the frame which are distanced from the ground, instead of letting it fall. As soon as the round bale is deposited, the bumper(s) spring(s) upwards and come(s) to bear against the periphery of the round bale. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     More closely described illustrative embodiments of an unloading apparatus and of a cover on a round baler are represented below in the drawing, in which: 
       FIG. 1  is diagrammatic, left side view of a round baler equipped with an unloading apparatus including a cover. 
       FIG. 2  is a left, rear perspective view of the unloading apparatus shown in  FIG. 1 , 
       FIG. 3  is a view like  FIG. 2 , but showing the unloading apparatus mounted to a baler axle, according to a first embodiment, wherein the axle is round in cross section and showing opposite halves of the cover separated from each other and removed from the axle, 
       FIG. 4  is a view like  FIG. 3 , but showing the unloading apparatus mounted to a baler axle, according to a second embodiment, wherein the axle is square in cross section, 
       FIG. 5  is a left, rear perspective view of the unloading apparatus according to a third embodiment, wherein a belt is mounted about the cover and a roller at a rear location of the apparatus just ahead of the bumper, and 
       FIG. 6  is a view similar to that of  FIG. 5  but showing a fourth embodiment wherein the cover is mounted to a roller located in front of the axle. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   A round baler  10  shown in  FIG. 1  is of standard construction, i.e. it has a superstructure  12 , a chassis  14 , a drawbar  16 , a crop receiver  18 , a bale chamber  20  and a feed apparatus  22 . In addition, an unloading apparatus  24  and a cover  40  are provided, which differ, however, from the prior art or are unknown there. 
   The round baler  10  is represented as a drawn round baler  10  having a size-variable bale chamber  20 ; it could equally well be a self-propelling round baler  10  and/or one having a constant-size bale chamber  20 , the type of (non-detailed) press elements being immaterial. 
   The superstructure  12  rests on the chassis  14  and bears the crop receiver  18 , the feed apparatus  22  and the unloading apparatus  24  and forms the bale of chamber  20  between (non-detailed) single-part of multipart side walls. 
   the chassis  14  contains a rigidly or resiliently fitted cross-stay  26 , which at the same time serves as an axle for wheels  28 . 
   The drawbar  16  is connected in a rigid or a vertically pivotable manner to the superstructure  12  and serves for the connection to a towing vehicle (not shown). 
   The crop receiver  18  is also referred to as a pick-up and is connected in a vertically movable manner to the superstructure  12 , as is likewise known. 
   The bale chamber  20 , at a front, lower region, has an inlet  30  for the feed crop, which connects directly to the feed apparatus  22 . 
   The feed apparatus  22  can be rigidly or movably connected to the crop receiver  18  or the superstructure  12  and contains, inter alia, in a non-detailed manner, a feed rotor, a feed channel wall, blades and the like. The feed apparatus  22  has the function of accepting crop brought up from the crop receiver  18  and of transporting it cut or uncut into the bale chamber  20 . 
   Referring now also to  FIG. 2 , it can be seen that the unloading apparatus  24  comprises a frame  32 , carrying elements  34 , a stop  36  and one or more bumpers  38 . In addition, a cylindrical tubular cover  40  is provided, which, depending on the illustrative embodiment, lies adjacent to the unloading apparatus  24  or is part of the latter. 
   The unloading apparatus  24  has the function of making a round bale released from the bale chamber  20  roll gradually onto the ground. For this purpose, it is connected to the superstructure  12  in a vertically pivotable or rigid manner, depending on the size of the wheels  28 . In the shown illustrative embodiment, a pivotable unloading apparatus  24  is assumed, which is located in an upper position during the pressing operation of the round baler  10  and a lower position during its unloading operation, as is known per se however. In the case of a vertically pivotable unloading apparatus  24 , suitable apparatuses (not shown), for example springs, rods, control surfaces on the discharge gate of the round baler or the like are provided to bring the unloading apparatus  24  back into the upper position. In the case of a vertically rigid unloading apparatus  24 , there is no need for the stop  36 . 
   The frame  32  includes on each side a side plate  42 , which side plates are spaced apart in the transverse direction by the greatest part of the width of the bale chamber  20  and are mutually stiffened by means of stays  44 . The side members  42  are mounted on the cross-stray  26  in a vertically pivotable manner by means of bearings  68 , the bearings  68  being situated at approximately one-third of the length of the side members  42 , measured from their front edge nearest to the drawbar  16 . These bearings  68  can be configured according to choice, for example as sleeves, as is shown in  FIG. 6 . 
   In the present illustrative embodiment, the carrying elements  34  are configured as rollers, having opposite ends respectively rotatably mounted in the side members  42 . The carrying elements  34  extend mainly parallel to the axis of the round bale to be supported and have a mutual clearance which is sufficiently small that no round bale can settle between the carrying elements. In addition to (see  FIG. 2 , for example), or instead of, (see  FIG. 3 , for example) the stays  44 , the axles of the carrying elements  34  are used to stiffen the frame  32 . 
   The stop  36  is in this case provided on the superstructure  12  and can be fitted both adjustably and rigidly. In the present illustrative embodiment, it is formed by a transversely running stay. The location of the stop  36  is chosen such that the bumper  38 , in the lowered position of the unloading apparatus  24 , when not laden with a bale, does not touch the ground. 
   The bumper(s)  38  is/are configured as leaf springs and has/have almost the length of the side members  42 . In the shown illustrative embodiment, a bumper  38  is screwed to each side plate  42 , to be precise at the spot where the rearward stay  44  is also fastened. Since the function of a bumper  38  mainly consists in preventing the round bale from rolling back, a single bumper  38 , which could be fitted, for example, in the middle of the stay  44 , is basically sufficient. At the free end of the bumper  38 , a foot  46  is provided, which itself then continues to ensure a short distance of the bumper  38  to the ground when a round bale is resting on it. Similarly, a net material covering the circumference of the round bale is not damaged by a sharp edge of the bumper end, since the foot  46  offers a larger contact surface. The foot  46  is essentially configured as a horizontal “U”, one arm of which is screwed to the bottom side of the bumper  38 . As is shown, in particular, by a glance at  FIG. 1 , a bumper  38  does not constitute a rectilinear extension of the side plate  42 , but runs angled-off slightly upwards relative to the latter. Although the bumper  38  exhibits a number of advantages, it is not necessary for the maintenance of the spin in the round bale. 
   In the illustrative embodiment according to  FIGS. 2 ,  3  and  5 , the cover  40  is configured as a tube which encompasses the cross-stay  26  and thus shields this against the round bale. The cover  40  is configured in multipart construction as half-shells and can be joined together in axially running joints  48 , for example with a cover plate  50 , and can thus be mounted and fitted onto the cross-stray  26  in the radial direction. To enable the cover  40  to rotate with as little friction as possible on the cross-stray  26 , bearings  52  are provided, the configuration of which varies according to  FIGS. 3 ,  4  and  5 , whereas their function is the same. According to  FIG. 3 , brackets  54  are provided, which are screwed, clamped or welded onto the cross-stay  26  and rotatably support three rollers  56  in the corner regions of an isosceles triangle, a circumferential circle around the rollers  56  substantially corresponding to the inner circumferential circle of the cover  40 . A plurality of bearings  52  are distributed over the length of the cross-stay  26  between the side members  42 , so that, depending on the anticipated load, the cover  40  can be securely supported and shielded. According to  FIG. 4 , bearings  52  configured as plain bearings  54  are provided and like the bearing brackets  54  according to  FIG. 3 , are clamped to the cross-stay  26 . In order to secure the cover  40  axially on the cross-stray  26 , axial stops  70 , for example rings, are provided, which are connected to the inner face of the cover  40  and bear externally against the bearins  54 . In other embodiments of the cover  40 , axial stops  70  can also be provided in one way or another According to  FIG. 5 , the cross-stay  26  is either of round configuration in cross section or an inner tube is slipped onto and fastened to it. The cover  40  thus slides on the externally round cross-stay  26  or on the inner tube surrounding it, so that as large a slide surface as possible is obtained. Common to all these embodiments is that a rotating cover  40  is provided, which shields the relevant static region of the superstructure  12 —the cross-stay  26 —and is situated between the bale chamber  30  and the unloading apparatus  24 . 
     FIG. 5  shows an embodiment in which the carrying element  34  is realized as a continuous belt or band and which at the front, i.e. nearest to the cross-stay  26 , is wrapped around the there-situated cover  40  and at the rear around a return roller  58 . The return roller  58  is rotatably mounted in the end regions of the two side members  42 , which in this illustrative embodiment do not necessarily converge towards the rear. Other than it is represented, the frame  32  could also be configured equal in width throughout its length. In this illustrative embodiment, the bumper  38  is configured as a horizontal U-bar, which is configured rigidly and not resiliently per se and the free arm ends of which are mounted in a vertically pivotable manner on a pivot axle  60  of the return roller  58 . Close to the arm ends, lever arms  64  extend downwards on the bumper  38 , which are acted on by springs  66  supported on the other hand, on the side members  42 . 
   In terms of the side members  42 , the return roller  58  and the bumper  38 , the embodiment according to  FIG. 6  is realized the same as in  FIG. 5 . Although the carrying element  34  is also provided, this now extends beyond the cross-stay  26 , is guided in front of the latter around a further return roller  62  and thus accommodates the cross-stay  26  in the enclosed space between its strands. In this embodiment, therefore, the carrying element  34  assumes, at the same time, the function of the cover  40 . 
   The configuration of the carrying elements  34  according to  FIG. 5  and/or  6 , i.e. as a conveyor belt, constitutes per se an independent invention which is independent of the cover  40 . 
   After all this, it is evident that a round bale discharged from the bale chamber  20  cannot come to bear against a rigid region of the superstructure  12 , but rather lands in each case on the cover  40  and thereupon maintains its rotary motion. The round bale makes its way rotating rearwards and downwards on the carrying element  40  and over the bumper  38  onto the ground and is there prevented from rolling back by the free end of the bumper  38 . 
   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.