Abstract:
A baler having a baling chamber of rectangular cross section includes a bale ejection arrangement that is mounted adjacent a bottom wall of a rear section of the baling chamber. The bale ejection arrangement comprises a plurality of transversely spaced, upper and lower pairs of laths. The upper and lower pairs of laths are interconnected by triangular shaped conveyor elements that are retracted from the baling chamber when the upper and lower pairs of laths abut each other. An extensible and retractable hydraulic actuator is coupled for simultaneously effecting longitudinal shifting movement of each of the lower pairs of laths, and as the actuator extends, the conveyor elements first raise into the baling chamber and then the upper and lower pairs of laths are moved as a unit so that any crop located in the baling chamber is advanced to the rear and removed from the baling chamber.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention concerns a baler with a rectangular or slab-shaped baling chamber and a bale ejection arrangement with at least once conveyor element that can be shifted in the longitudinal direction of the baling chamber by means of a motor that can occupy at lest one first position, in which it is arranged at least generally outside of the baling chamber, and a second position in which it projects into the baling chamber.  
       BACKGROUND OF THE INVENTION  
       [0002]     WO-A96 29 196 shows a baler with a bale ejection arrangement for the ejection of bales from a baling chamber. The ejection arrangement is equipped with conveyor elements that can be brought out of a first position, in which the conveyor elements are arranged outside of the baling chamber, into a second position in which the conveyor elements project into the baling chamber by means of spring action, in order to engage a bale.  
         [0003]     The problem underlying the invention is seen in the fact that the conveyor elements of such bale ejection arrangements on balers do not project into the bale or project only to an inadequate degree and do not convey the bale or do so non-uniformly, or that damage to the bale can result from jams, for example, in the form of wet harvested crop, branches, stones etc. due to particularly densely compressed bales or metal fatigue of the spring.  
       SUMMARY OF THE INVENTION  
       [0004]     According to the present invention, there is provided an improved bale ejection arrangement for ejecting crop from the baling chamber of a large square baler.  
         [0005]     An object of the invention is to provide a large square baler with a bale ejection arrangement that mounted adjacent a baling chamber and includes conveyor elements which normally are located outside the baling chamber but which may be moved into and shifted to the rear within the baling chamber so as to remove crop located there.  
         [0006]     In this way, a bale ejection arrangement is made available which is equipped with conveyor elements that securely engage or are inserted into the bale that is to be conveyed. Such a bale ejection arrangement is provided on a baler having a slab-shaped or rectangular cross section baling chamber. A baler of this type may be an industrial baler, for example, for baling paper, woven textiles or cloth, garbage etc., but in particular for a baler for agricultural harvested crop, for example, in the form of a large square baler. The bale ejection arrangement is provided with at least one conveyor element that can be shifted in the longitudinal direction of the baling chamber by means of a motor, the conveyor element occupying at least a first position, in which it is arranged at least generally outside of the baling chamber and a second position in which it projects into the baling chamber. In the first position, it does not interact with the material in the baling chamber or with a bale arranged there or it does not engage or is inserted into such a bale, and thereby does not offer any restriction to the flow of the harvested crop or to the transport of a bale during a normal baling operation. In its second position, the conveyor element projects into the baling chamber and thereby engages the material or the bale, or is inserted into it in order to transport it out of the baling chamber or to eject it. The conveyor element can be moved by the motor not only in the longitudinal direction but can also be brought from its first position into its second position. This motorized actuation provides the assurance that the conveyor element can completely engage into the bale or the material located in the baling chamber, even in the case of an obstruction, a jam or the like, in order to remove it completely from the baling chamber or in the case of a wrapped bale with a minimum of damage or free of damage.  
         [0007]     If the bale ejection arrangement is provided with at least two laths that are at least generally parallel to each other, then the conveyor element can be moved by being connected to one or both of the laths and the laths are moved with respect to each other or are shifted relative to each other. The movement of the conveyor element out of its first and into its second position can be performed in a simple way by the same motor, in that the conveyor element is connected in joints to the first of the laths as well as to a second lath and thereby upon a shifting of the laths against each other is erected relative to the laths or in order to be brought into an at least generally vertical position.  
         [0008]     In order to move the lath or the laths or the conveyor element, the motor can interact with one of the laths or engage one of the laths directly or indirectly, for example, over one or more linkages or gearboxes.  
         [0009]     Provision can be made for the laths to be provided alongside each other or at least generally adjoining each other horizontally. The least possible space requirement and a favorable course of movement of the conveyor element results in the case that it is connected in joints to the first as well as to the second lath and thereby describes a curve upon a shifting of the laths relative to each other if the laths are arranged at least generally adjoining each other vertically or arranged one above the other.  
         [0010]     If the laths are arranged adjoining vertically or one above the other, then the motor preferably engages the lower of the two laths, since in this way intervening levers or linkages can be omitted without the motor necessarily being arranged in close proximity to the baling chamber or a floor of that chamber, which could lead to impediments or limitations of the construction space or the dimensions of the motor.  
         [0011]     The motor could be configured, for example, in the form of an electric motor or any other appropriate motor. The use of a hydraulic motor, however, is particularly favorable, since balers or towing vehicles towing these are frequently provided with sources of hydraulic pressure that are usually appropriate to supply this additional hydraulic motor with hydraulic pressure.  
         [0012]     In order to assure a uniform bale ejection or a uniform ejection of material, and to counteract any damage to the bale due to an excessive force at a localized point and in order to accelerate the ejection process by reducing the necessary ejection strokes, the bale ejection arrangement can be provided with several conveyor elements. The conveyor elements can be provided offset in the baling chamber or at one or more surfaces of the baling chamber, such as, for example, the floor of the baling chamber. But a simple drive without the use of gearboxes etc. by the motor results from the conveyor elements being arranged in one or more rows extending in the direction of the ejection of the bale.  
         [0013]     Each row can be associated with a first and a second lath, where the laths can be connected, for example, in such a way that they can be moved in unison by the motor, in that they are, for example, connected by a transverse strut that may be bolted, welded or the like.  
         [0014]     If the laths are provided so that they can be slid in the longitudinal direction of the baling chamber, then in addition to the movement of the conveyor element in the baling chamber and out of it, the actual ejection movement of the conveyor element can be performed by a movement of the laths, preferably by means of the motor. This can be accomplished by first shifting the laths relative to each other so as to move the conveyor element in the baling chamber or out of the latter, in order to be moved further subsequently in the direction of the baling chamber, so that the conveyor element performs an ejection movement and the bale is transported in the direction of an outlet opening of the baling chamber. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The drawing shows an embodiment of the invention that shall be described in greater detail in the following.  
         [0016]      FIG. 1  shows a schematic side view of a baler according to the invention with a bale ejection arrangement.  
         [0017]      FIG. 2  shows a perspective plan view of the bale ejection arrangement by itself.  
         [0018]      FIG. 3  through  5  show side views of the bale ejection arrangement with conveyor elements that are located in various positions. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0019]      FIG. 1  shows a baler  10  in the form of a large baler for the production of slab-shaped bales that contains a frame  12  that is supported on ground support wheels  14  in tandem arrangement. A towbar  16  is connected to the frame  12  and extends from the latter to the front and is configured in such a way that it can be connected to a towing vehicle such as an agricultural tractor, not shown, which is equipped with a power take-off shaft in order to deliver power to drive various driven components of the baler  10 . A baling chamber  18  or an enclosure with rectangular cross section is formed in part by an upper housing wall  20  and a lower housing wall  22 , where the lower housing wall  22  is provided with a crop inlet opening  24 , to which a curved supply channel  26  is connected, that is used as a rough pressing chamber, as is described in the following. A take-up arrangement  28  in the form of a pick-up with a screw conveyor conveying to the center is arranged ahead of the supply channel  26  in order to raise a swath of harvested crop from the ground and to deliver it to a compression fork  30 , that is used to compress harvested crop into the supply channel  26 , until a load of predetermined density has been collected downstream of fingers  32  of a retention arrangement  34 , where the retention arrangement  34  is mounted so as to pivot between a retention position, in which the fingers  32  project into the supply channel  26  in the vicinity of the crop inlet  24 , and a supply position, in which the fingers  32  are withdrawn from the supply channel  26 , as shown in  FIG. 1 , in order to permit the load of harvested crop to be pushed across the crop inlet  24  by means of a loader fork assembly  36  into the baling chamber  18 . A spring-loaded flap  38  is mounted, free to pivot, at a forward, lower location of the supply channel  26 , that pivots as a function of the harvested crop located in the supply channel  26 , when the crop reaches a predetermined density, in order to supply an electric control circuit (not shown) with current, which provides corresponding drive connections that at first brings about a movement of the retention arrangement  34  in such a way that it retracts the fingers  32  out of the blocking position into the position shown in  FIG. 1  and then activates the loader fork assembly  36  in such a way that thereupon the loader fork assembly  36  can slide through the supply channel  26  and can move the load of harvested crop into the baling chamber  18 . Once the load of harvested crop has been pushed into the baling chamber  18 , a piston mechanism  40 , arranged at a forward end of the frame  12 , is actuated in a controlled sequence after the loader fork assembly  36 , in order to move the harvested crop to the rear into the baling chamber  18 , where it is compressed in a stack, as this is well known in the state of the art. After the stack of compressed material has reached a predetermined length, a needle assembly  42 , including several curved needles  68  for the delivery of wrapping yarn, is actuated, so as to conduct several strands of yarn to a corresponding number of knot-tying devices, not shown, that operate in such a way that they lay lengths of yarn around the predetermined length of the stack, in order to form a bale  44  that is ready for unloading, which occurs when it is forced out of the rear end region of the baling chamber  18  by a partial bale  46 , when it increases in its length, since new loads of harvested crop are pushed into the baling chamber  18 .  
         [0020]     If reference is now made to the details of the piston mechanism  40 , it can be seen that the latter includes a baling piston  48  that is arranged for a back-and-forth movement in the baling chamber  18  between a retracted position ahead of the crop inlet  24  and an extended position beyond the crop inlet  24 . This movement of the baling piston  48  has the result that loads of harvested crop that are introduced into the baling chamber  18  from the supply channel  26 , are compressed against a stack of harvested crop that includes a partial bale  46  and/or the complete bale  44 . Moreover the piston mechanism  40  includes a drive  50  configured as an extendible and retractable actuation arrangement, which is pictured here as a double-acting hydraulic cylinder and piston unit, whose cylinder end is anchored by a pin  52  to the frame  12 , free to pivot, at a point above the compression fork  30 . The piston end of the drive  50  is connected at a connecting point  54 , perhaps with a pin, at a point between opposite ends of a first steering arm  56 , used as a crank arm, whose forward end region is connected at a bearing location  58 , free to pivot, to the frame  12 . A rear end region of the first steering arm  56  is connected in a bearing location  60 , perhaps by a pin, to a forward end region of a second steering arm  62  operating as connecting rod, whose rear end region is connected in a bearing location  64  to the baling piston  48 , perhaps by a pin. It should be noted here that, when the baling piston  48  is at its rearmost position, as shown in  FIG. 1 , the pins connecting the bearing locations  58  and  64  are arranged along a line of centers that lies along or approximately along a central longitudinal axis of the baling chamber  18 . This has the result that the reaction force of the harvested crop, that acts upon the baling piston  48  is generally absorbed by the drive  50  when the first and the second steering arms  56  and  62  are located along a line which is the case when the baling piston  48  is in its rear end position. Furthermore it should be noted that each of the two steering arms  56  and  62  could be configured as a pair of steering arms spaced at a distance from each other in the transverse direction. Then the drive  50  could be connected at the connecting point  54  (pin) at a location between the pair of steering arms  56  that form the first steering arm  56 . Therefore it can be seen that the baling piston  48  forms the slider of a slider-crank mechanism that includes the first steering arm  56  as a crank arm, and the second steering arm  62  as the connecting rod. Although the linkage formed by the steering arms  56  and  62  does not move beyond a dead center position, it could be characterized as a toggle mechanism or toggle joint. Although the preferred embodiment shows a drive  50  that is connected to the first steering arm  56  at a point between the opposite ends of the steering arm  56 , the drive could furthermore be connected at any point between the bearing location  58  and the bearing location  64 , for example, the drive  50  could be connected to the pin  60  or at a point along the length of the second steering arm  62 , where the operation could be improved over the known configuration, in which the actuating arrangement is connected directly to the baling piston  48 .  
         [0021]     Further details of this baler  10  are described in EP-A2-0 940072, whose disclosure is incorporated herein. It should be noted that in place of this special drive with a hydraulic motor, a conventional crank drive could be used.  
         [0022]     The piston mechanism  40  contains the baling piston  48  that can be slid between two end positions by means of the drive  50  as is described by EP-A2-0 940 072.  
         [0023]     The bearing location  58  for the control of the first steering arm  56  is configured in such a way that it can be repositioned in its height as well as in the longitudinal direction of the baling chamber  18 , for example, on an inclined plane, so that each of the two steering arms  56 ,  62  in their extended position extend in the longitudinal center plane of the baling chamber  18 . Indeed, this is only a preferred embodiment that can be omitted here. Depending on the configuration of the guidance of the baling piston  48 , the two steering arms  56  and  62  can also engage offset to the center of the baling chamber  18 , that is, the bearing location  58  of the steering arm  56  is unchanged.  
         [0024]     A knot-tying assembly  66  is provided in known manner on the upper side of the upper housing wall  20  and to the rear of the supply channel  26 , into which the needles  68  of the needle assembly  42  can enter. The needle assembly  42  includes, on each side, a needle carrying arm  70  that can pivot in a vertical plane and conducts the needles  68  through the baling chamber  18  with the yarn, not shown, to the knot-tying assembly  66  as soon as a bale  44  is to be wrapped.  
         [0025]     Moreover the lower wall  22  of the baling chamber  18  is arranged in a conventional configuration as a steel sheet metal part, if necessary, profiled, which extends over the entire length of the baling chamber  18  and is arranged as a stationary component on the frame  12 . The wall  22  is provided with the crop inlet  24  for the supply channel  26  and an opening for the entry of the needles  68 . In a rear region of the baling chamber  18 , flaps that can be repositioned can be provided in known manner, which offer the bale  44  a certain resistance to movement.  
         [0026]     A bale ejection arrangement  72  is provided underneath the wall  22 . As can best be seen in  FIGS. 2-5 , the bale ejection arrangement includes several pairs of metal laths or strips  74  and  76 , respectively extending in the longitudinal direction of the baling chamber  18 . The pairs of laths  74  and  76  are arranged in parallel rows, where in the embodiment shown three rows, a central row and a left and a right row, are distributed uniformly over the width of the baling chamber  18 . Each row is provided with a first pair of laths  74  and a second pair of laths  76 , where the first pair of laths  74  are arranged vertically above the second pair of laths  76 .  
         [0027]     In the present embodiment, the pairs of laths  74  and  76  of each row are spaced from each other a short distance so as to define a slot in which a multitude of conveyor elements  80  are provided. Each of the conveyor elements  80  is connected in joints to the upper and the lower laths  74 ,  76  at connecting points  82 . In the region of the laths  74 ,  76  and the conveyor elements  80 , the bottom wall  22  of the baling chamber  18  is configured as a slotted component in such a way that the conveyor elements  80  can enter into and retract from the baling chamber  18  or can be moved relative to it, as is described in greater detail in the following.  
         [0028]     As can be seen best in  FIGS. 3 through 5  in connection with  FIG. 2 , the lower laths  76  are rigidly connected to each other by means of a bracket  84 . This bracket  84  engages a motor  86  in the form of a hydraulic cylinder extending in the longitudinal direction of the baling chamber  18 , the other end of the hydraulic cylinder is connected in a joint to the frame  12 , with the hydraulic cylinder  86  preferably being double-acting.  
         [0029]     In the following, the operation of the bale ejection arrangement  72  shall now be described in more exact detail.  
         [0030]     During the normal operation of the baler  10 , the bale ejection arrangement  72  is deactivated and is located in its position shown in  FIG. 3 , in which the motor  86  or the piston of the hydraulic motor is retracted and the conveyor elements  80  are in a position in which they do not project into the baling chamber  18  and thereby do not interfere with the transport of the bale by the baling piston  48 . The connecting points  82  of the conveyor elements  80  on the pairs of laths  74  and  76  are spaced away from each other in the vertical direction, whereby the connecting point  82  on each of the lower pairs of laths  76  is arranged to the rear of the connecting point  82  on each of the upper pairs of laths  74  with respect to the baling chamber  18 .  
         [0031]     If a bale  44  or a partial bale  46 , located in the baling chamber  18 , is to be removed from the latter, for example, after the conclusion of the harvesting operation or for purposes of maintenance or repair, then an operator will activate the bale ejection arrangement  72 . This activation can be performed, for example, by a control arrangement provided on the baler or on a towing vehicle connected to the baler. This control arrangement controls the motor  86  or connects the hydraulic motor to a pressure source, not shown, on the baler  10  or on the towing vehicle.  
         [0032]     If the motor  86  is activated or if it is supplied with hydraulic pressure in such a way that its piston is extended relative to the cylinder, then each of the lower pairs of laths  76 , which are connected to the motor  86  over the bracket  84 , are moved away from the baling piston  48  in the direction of the rear region of the upper housing wall  20 . Due to the action of the motor  86 , the lower pairs of laths  76  are moved to the rear relative to the upper pairs of laths  74 , as a result of which the connecting points  82  first approach each other in the horizontal direction (transition from the first end position shown in  FIG. 3  to that shown in  FIG. 4 ) and then pass each other (transition from the intermediate position shown in  FIG. 4  to the second end position shown in  FIG. 5 ). The connecting points  82  in the second end position are such that the connecting points  82  of the upper pair of laths  74  is arranged ahead of the connecting points  82  on the lower pair of laths  76 , in the embodiment shown. However, a geometry deviating from the above is also possible.  
         [0033]     Since the spacing of the connecting points  82  is determined by the rigid conveyor element  80 , the horizontal approach of the connecting points  82  towards each other results in an enlargement of the vertical distance, whereby the upper and lower pairs of laths  74  and  76  firs move away from each other during the shifting to the rear ( FIG. 4 ), in order to approach each other again immediately thereafter ( FIG. 5 ).  
         [0034]     The movement of the connecting points described here results in a corresponding movement of the conveyor elements  80  in such a way that these are raised from their position arranged outside of the baling chamber  18 , a generally non-vertical, non-operating position, into a generally vertical, operating position, in which they project through slots in the bottom wall  22  of the baling chamber  18  and engage into the bale  44  or partial bale  46  arranged there. If the conveyor elements  80  are now in their position projecting into the baling chamber  18 , a further operation of the motor  86  or a further extension of the piston of the hydraulic motor has the effect that both pairs of laths  74 ,  76  are shifted to the rear relative to the baling chamber  18  and that the conveyor elements  80  also slide to the rear in the slots in the chamber bottom wall and convey the bale  44  or the partial bale  46  out of the baling chamber  18 .  
         [0035]     In order to bring the conveyor elements  80  into their initial position again after the ejection of the bale or for the performance of a renewed ejection stroke, the motor  86  is retracted or the piston of the hydraulic motor is again brought into its retracted position, whereupon the pairs of laths  74 ,  76  are initially shifted relative to each other and thereby the conveyor elements  80  are brought into their non-operating position and subsequently the pairs of laths  74 ,  76  are themselves brought into their retracted position.  
         [0036]     The arrangement described here provides the assurance that the conveyor elements  80  engage themselves into the bale  44  or the partial bale  46  that is to be ejected, regardless of the question whether it is particularly dense and hence fully compressed or that jams or other impediments exist, since they (conveyor elements  80 ) are forced actively into the bale  44  or partial bale  46  by the action of the motor  86  and are not loaded by the force of a spring or the like. Beyond that, the conveyor elements  80  are brought again actively into their first position in which they do not project into the baling chamber  18  during the retraction for a renewed ejection stroke when the bale  44  or partial bale  46  are still in the baling chamber  18 , before they are retracted relative to the baling chamber  18 . In this way, damage to the bale  44  or partial bale  46  that is to be ejected as well as jams caused by broken harvested crop or material are counteracted.  
         [0037]     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.