Abstract:
A pick-up baler for agricultural produce with a compression piston  9  and a rotary conveyor, which rotates about an axis of rotation  18 , comprises rakes  21, 22 , which have axes  23  extending approximately parallel to the axis of rotation  18  of the rotor, convey the harvested crop through a supply channel  13 , can be swiveled about their rake axes  18  under the control of curves and of which at least one acts as a conveying rake  21 , the swiveling of at least one further rake, which functions as a supply rake  22 , being controllable as a function of the degree of filling of the supply channel  13  in such a manner that, when a specified degree of filling of the supply channel  13  is reached, the harvested crop, collected there, is conveyed over a baling channel inlet opening  12  into a baling channel  11 . The supply rake  22  is guided in a curved path  39 , which can be moved from a conveying position into a supplying position, whereas the conveying rakes  21  are guided in an immovable curved path  34.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a pick-up baler for agricultural produce. 
     In the DE 195 31 240 A1, such a baler is described, for which a rotary conveyor conveys harvested crops, picked up from the ground, through a conveying channel into a baling channel, in which individual rakes, which rotate about a rotor axis of rotation and are disposed, so that they can swivel about their own axes, which are parallel to the rotor axis of rotation, collect the harvested crops initially in the conveying channel and finally, due to a feeding motion of a rake, push it into the baling channel. The swiveling of the rakes, required for the conveying and feeding motions, is realized owing to the fact that the rakes are guided in a pivotable curved path, the degree of swiveling of which is fixed depending on whether the rakes carry out only a conveying motion, or a feeding motion. The swiveling of the curved path can be controlled over a sensor for determining the amount of harvested crops conveyed in such a manner, that the feeding motion is carried out only when a sufficient amount of harvested crops is present in the feeding channel. The quality of the conveying as well as of the feeding depends essentially on the swiveling motions, carried out by the respective rakes, an optimum motion of the rakes in the conveying function differing appreciably from an optimum motion in the feeding function. In the case of the known baler, however, because the swiveling of the rakes for the conveying function as well as the swiveling of the rakes for the feeding function are controlled by the same curved path, this can represent only a compromise between the guiding required for the optimum motion of the rakes for conveying and the optimum motion for feeding. 
     SUMMARY OF THE INVENTION 
     The invention is therefore concerned with the problem of indicating a pick-up baler, which can be constructed so as to be adapted better, with respect to its conveying function as well as with respect to its feeding function, to the particular configuration of the baler, especially of the feeding channel and of the transition region to the baling channel, but also to the harvested crops, which are to be baled. 
     This objective is accomplished by a pick-up baler with the distinguishing features of claim  1 . 
     Owing to the fact that the feeding rakes and the conveying rakes are guided in different curved paths, the latter can be adapted optimally to the main function of the respective rake, the curved path, guiding the conveying rakes, being constructed immovably, and only the curved path, guiding the feeding rakes, having to be constructed movably, so that the feeding rake can be converted from the conveying function to the feeding function. 
    
    
     Further advantages and details arise out of the dependent claims and from an example of the invention, which is described in the following and shown in the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 diagrammatically shows the side view of an inventive pick-up baler, 
     FIG. 2 shows the rotary conveyor of the pick-up baler in section, 
     FIG. 3 shows a perspective partial representation of the rotary conveyor, 
     FIG. 4 shows a different view of the object of FIG. 3, 
     FIG. 5 shows a section along the surface V-V in FIG. 4, 
     FIG. 6 shows a rear view of the supply channel with the rotary conveyor of the pick-up baler, 
     FIG. 7 shows an enlarged representation of the section VII in FIG. 6, 
     FIGS. 8 a  to  f  show the course of movement of the supply rake in the conveying position, and 
     FIGS. 9 a  to  f  show the course of movement of the supply rake in the supplying position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The pick-up baler, shown in FIG. 1, is supported by wheels on the ground  2  and can be connected over a shaft  3  with an agricultural tractor. The driving direction of the tractor is indicated by an arrow  6 . The pick-up piston baler can, however, also be constructed as a self-propelled, automatically driven agricultural vehicle. The embodiment shown is driven by the power take-off of the tractor over an articulated shaft  4 . This propulsion is transferred over a main transmission  7  and a crank shaft  8  to a plunger  9 , which moves back and forth in the direction of the double arrow  10  in a baling channel  11  and in this way compresses harvested crops, supplied through a baling channel inlet opening  12  to a supplying channel  13 , into a bale, around which tying material is then wound by indicated tying needles  14  and the knot-forming device  15 . 
     Moreover, the rotor  16  is rotated by the main transmission  7  in the direction of the arrow  17 . The rotor  16  consists of two rotor disks  20 , which are connected with a rotor shaft  19  mounted rotatably about a rotor axis of rotation  18  and in which the rakes  21 ,  22  are mounted so that they can be swiveled about their axes  23 . They convey harvested crops, such as straw, hay or incipiently withered green crops, which has/have been picked up from the ground by a device, which is referred to as a pick-up  24 . 
     As shown by FIGS. 2 to  5 , the rakes  21 ,  22  are formed by prongs  26 ,  27 , which are fastened to crossarms  25  and are disposed next to one another at the crossarms  25  over the whole width of the supply channel  13 . The supply channel  13  has an essentially continuous external wall  28  and an internal wall, which faces the rotor  16  and is formed by profile plates  29 , which are spaced apart. These are disposed in such a manner in the gaps between the prongs  26 ,  27 , that the prongs  26 ,  27  can reach through the supply channel  13 . 
     In order to be able to direct the swiveling motions of the rakes  21 ,  22 , the crossarms  25  are extended on one side beyond the rotor disks  20  and, at the extended region, have control plates  32 , which are connected firmly with the crossarm  25  and are provided with control rollers  30 ,  31 . The rotary conveyor shown has six rakes  21 ,  22 , of which five are constructed strictly as conveying rakes  21  and one functions as supply rake  22 . 
     As can be seen particularly in FIGS. 2 and 5, the control rollers  30 ,  31  of the conveying rakes  21  are guided in the driving direction  6  to the left of the left rotor disks  20  in a curved path  34 , firmly connected with the housing  33 . In order to achieve a movement of the conveying rakes  21 , advantageous for the conveying movement, the curved path  34  is constructed in several parts and has a wide channel  35 , in which the larger of the two control rollers  30  is guided, and a narrower channel  36 , in which the smaller of the two control rollers  31  takes the over the guiding regionally. In this way, it is achieved that the tips of the prongs  26  of the conveying rakes  21  describe the envelope curve  37 , shown in FIG. 2, during a rotation of the rotor  16 . This conveying motion is particularly advantageous, since it conveys the Harvested crops, transferred from the pick-up  24 , rapidly from the inlet region  38  of the supply channel  13  without bringing about any excessive consolidation of the harvested crops during the further passage of the harvested crops through the supply channel  13 . 
     On the other hand, the crossarm  25  of the supply rake  22  is extended to the other, in the driving direction  6  left side through the left rotor disks  20  and likewise is equipped with a control plate  32  and control rollers  30 ,  31 . These control rollers  30 ,  31  run in a curved path  39 , which is also constructed in several parts and also, like the immovable curved path  34 , has a wide channel  40  for the large control roller  30  and a narrow channel  41  for the smaller control roller  31 . However, in contrast to the fixed curved path  34 , the curved path  39  is movable in that it can be mounted so that it can swivel about the rotor axis of rotation  18 . 
     In the not-swiveled state of the curved path  39 , the latter is in the conveying position and guides the supply rake  22  in such a manner, that the prongs  27  of this rake carry out a conveying motion similar to that of the prongs  26  of the conveying rake  21 . In FIGS. 8 a  to  8   f , the course of the movement of the prongs  27  of the supply rake  22  in the conveying position during a rotation of the rotor  16  is shown in movement stages of 60° in the clockwise direction. The envelope curve  42 , described by the tips of the prongs  27 , is also drawn in these Figures. It differs identifiably from the envelope curve  37  of the movement of the prongs  26  of the conveying rakes  21 , since the movable curved path  39  is designed optimally for the supply position and not for the conveying position. 
     The movement of the prongs  27  of the supply rake  22  into the supply position with the swiveled curved path  39  is shown in FIGS. 9 a  to  9   f , in which the reference number  43  refers to the envelope curve of the tips of the prongs in the supply position. 
     The swiveling of the curved path  39  as a function of the degree of filling of the supply channel  13  is controlled by the pressure sensor device, described in the following. For this purpose, a retainer is present, which is disposed below the baling channel inlet opening and has a retaining shaft  44 , which extends, in the driving direction behind the supply channel  13  and to which retaining plates  45  are fastened, which reach the supply channel  13  through slots  46  introduced into the outer wall  28  of the supply channel  13  (see FIGS. 3,  4  and particularly  6 ). The retaining shaft  44  is mounted so that it can be rotated and, over a lever arm  47  fastened to the retaining shaft  44 , connected with a spring  48 , the force of which holds the retaining plates  45  in the position in which they reach through the supply channel  13 . When the supply channel  13  is filled to such an extent with harvested crops by the conveying motion of the rakes  21 ,  22  that the pressure, exerted on the retaining plates  45  by the harvested crops exceeds the force of the spring  48 , the retaining shaft  44  rotates and the retaining plates  45  swivel out of the supply channel  13  and open up the baling channel inlet opening  12 . At the same time, the comb-like configuration of the retainer with a plurality of retaining plates  45  is advantageous, since these exert a distributed retaining force on the harvested crops and, combing through the latter, equalize it so that approximately the same amount of harvested crops is supplied over the whole width of the supply channel  13  to the baling channel  13 . The amount of harvested crops, supplied to the baling channel  11  during each supplying motion, can be affected by the selection of the force of the spring  48 , which may also be adjustable. 
     For the embodiment shown, the retaining movement of the retaining plates  45  is brought about only by the pressure on the harvested crops. It is, however, also possible, in the case of a retraction movement initiated by the pressure of the harvested crops, to support or actively carry out completely the complete retraction of the retainer from the supply channel  13  by a driving mechanism, which may be of advantage in the case of sensitive harvested crops. 
     Aside from the lever arm  47 , a switching linkage  49  is connected with the retaining shaft  44 . It extends through a frame stretcher  50  of the pick-up baler and is connected with an anvil latch  51 , in that a bolt  52  of the switching linkage  49  is guided in an elongated hole  53  of the anvil latch  51 . The elongated hole  53  fulfills a buffer function, so that small movements of the switching linkage  49  are not transferred directly to the anvil latch  51 . This can be seen particularly in FIG.  7 . In the case of a larger movement of the switching linkage  49 , as caused by pulling the retaining plates  45  out of the supply channel  13 , the tension linkage  49  leads to a swiveling of the anvil latch  51  about a bearing bolt  54 , which is connected with the rigid side wall  55  of the rotary conveyor. The anvil latch  51  swivels in the direction of the arrow  58  against the force of a tension spring  56 , which is also connected with the side wall  55  over a stop  57  and, by these means, releases a roller  59  of a pawl  60 , which is supported at the anvil latch  51 . 
     The pawl  60  is part of a rotating joint  61 , which belongs to a synchronizing device. The latter ensures synchronization of the movement of the movable curved path  39  and, with that, of the supplying motion of the supply rake  22 , with the movement of the compression piston  9 . The supplying motion can therefore take place only if the compression piston  9  releases the baling channel inlet opening  12 . 
     For this purpose, in the case of the embodiment shown, the rotor  16  is driven by the main transmission  7  at the same rpm. The synchronization device ensures that the swiveling of the movable curved path  39  and, with that, the supply motion of the supply rake  22  is initiated only at a specified angle of rotation of the rotor  16 . For this purpose, the rotating joint  61  has a coupling element, which is constructed as a coupling cage  72 , is connected firmly with the rotor shaft  19  and is rotated constantly with the latter. A coupling element embraces a clutch hub  62 , the pawl  60  and a further coupling latch  64 . The pawl  60  is mounted on the clutch hub  62 , which is stationary in the uncoupled state and, due to being supported with the roller  59  on the anvil latch  51 , is held outside of a coupling engagement  71  of the coupling cage  72 . Over coupling catches  67 ,  68 , the second coupling latch  64  is also held outside of the coupling engagement  71  of the coupling cage  72 . 
     If the anvil latch  51  releases the roller  59  of the pawl  60 , the latter is swiveled by a spring  66 , which is supported at a pin  65  in the pawl  60  against the clutch hub  62 , about a swivel pin  69  in the direction of the coupling cage  72  and, with a roller  70 , then latches in the coupling engagement  71  of the coupling cage  72  when the latter, during its rotation, has reached the angle of rotation assigned to the pawl  60 . Only when the pawl  60  is swiveled into the coupling engagement  71  of the coupling cage  72 , is the coupling latch  64 , with its roller  70  also swiveled over the coupling catches  67 ,  68  into the coupling engagement  71  of the coupling cage  72 . Accordingly, a rotational coupling between the coupling cage  72  and the clutch hub  62  is achieved, the pawl  60  causing the clutch hub  62  to be carried along with the coupling cage  72  and the coupling latch  64  preventing the clutch hub  62  from leading the coupling cage  72 . If the clutch hub  62  and the coupling cage  72  are connected in this manner, the rotating joint  61  is in the coupled state and the clutch hub  62  rotates with the coupling cage  72 . This course of motion is shown in FIGS. 9 a  to  9   f.    
     The clutch hub  62  is connected with a curved path movement device, which is not shown in FIG. 7 for reasons of clarity. As shown particularly in FIG. 6 but also in FIGS. 8 and 9, the curved path movement device has a rocker arm arrangement  73 , which converts a rotation of the clutch hub  62  over a coupling bolt  74  into a swiveling of the movable curved path  39  about the rotor axis  18 . The magnitude of the swiveling angle of the curved path  39  and the course of the velocity of the swiveling motion are fixed by the frame sizes of the rocker arm arrangement  73 . The coupling bolt  74  connects the movable curved path  39  with the rocker arm arrangements  73 , in that it reaches through a recess  75  in the wall  55  of the housing. 
     The inventive pick-up the baler furthermore may have a display device, which is not shown and which indicates whether the rotating joint  61  is in the coupled or uncoupled state. By these means, the person operating the pick-up baler receives information concerning the rate of the utilization of the baler. If the coupling cage  72  of the rotating joint  61  is rotating constantly in the coupled state, then a supplying motion is carried out by the supply rakes  22  during each rotation of the rotor  16  and the baler is utilized well. On the other hand, if the rotating joint stops from time to time, that is, if it is uncoupled doing some rotations, the amount of harvested crops taken up by the pick-up  24  is not sufficient so that a supply motion can take place during each revolution of the rotor  16 . 
     Inventive pick-up balers can also be designed so that the rotor  16  rotates at a whole number multiple of the movement frequency of the compression piston  12 . The number of conveying rakes  21  can be reduced by these means. However, in the case of such balers, it is necessary to provide the synchronization device with an additional control, which makes coupling possible only at a specified position of the compression piston  9 . On the other hand, the rotor  16  can also rotate at a fraction of the frequency of the compression piston  9 , such as ½, ⅓, ¼ etc. It must then have a correspondingly larger number of supply rakes  22  and an appropriate number of coupling engagements  71  in the coupling cage  72  or counter elements. As a result of the slower motion of the rotor  16 , which is possible therewith, the forces, acting on the rakes  21 ,  22  and the wear on the rotary conveyor, can be reduced as a whole.