Abstract:
A large round baler includes a device for introducing a wrapping web to the baling chamber for wrapping a bale with the wrapping web. During a wrapping procedure, the wrapping web is pulled off a supply roll and directed to a location in front of the baling chamber where it is engaged by a crop supply unit and introduced into the baling chamber where the rotating bale carries the wrapping web about it and becomes wrapped.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention pertains to a baler with a baling chamber, a crop material supply unit that can convey crop material to the baling chamber, and a device for wrapping a bale with a wrapping web, which has means that pull a wrapping web off a supply in the nature of a roll, for instance.  
       BACKGROUND OF THE INVENTION  
       [0002]     DE-C2-36 17 155 shows a round baler with a device for wrapping a bale with a wrapping web and having a feed mechanism that first draws off the wrapping web from a supply in order then to lay it down on a hold-down device and bring it up to a starting roll that seizes the wrapping web and supplies it to the bale to be wrapped.  
         [0003]     The problem underlying the invention is seen in the fact that such a baler with a device for wrapping a bale comprises many individual parts for supplying the wrapping web to the bale and is thus expensive to manufacture and maintain.  
       SUMMARY OF THE INVENTION  
       [0004]     According to the present invention, there is provided a large round baler having a novel web delivery arrangement for introducing a web of material into the baling chamber.  
         [0005]     An object of the invention is to provide a web delivery arrangement which comprises an economical combination of separate parts.  
         [0006]     A baler is shown with a baling chamber, a crop material supply unit that can convey crop material into the baling chamber and a device for wrapping a bale with a wrapping web, which has a means that draw off a wrapping web from a supply in the nature of a roll, for instance, the device being able to bring the wrapping web to the crop material supply unit such that it is seized thereby and conveyed in the direction of the bale. In this way, it is possible to forgo supply mechanisms that bring the wrapping web to the bale so that it can be seized by the bale, since this function is already fulfilled in essence by the crop material supply unit. During the actual formation of the bale, the crop material supply unit serves to convey crop material into the baling chamber. During the wrapping process, on the other hand, it conveys the wrapping web in the direction of the bale.  
         [0007]     The crop material supply unit preferably involves a conveyor rotor designed in the usual manner which is equipped with driving elements that convey crop material into the baling chamber of the baler. The crop material supply unit can also be constructed as a belt conveyor, a conveyor auger, a conveyor roller, or in any other suitable manner.  
         [0008]     By virtue of a guide unit, constructed preferably in the manner of a channel and/or a guide surface that extends from the web feed roller up to the crop material supply unit, the supply of the wrapping web to the bale can be further improved, since a contact between the wrapping web and baling material and/or, in particular, moving components of the baler is counteracted. The guide unit can be constructed in the form of a channel that is essentially closed off at least on the top and the bottom, but it can also be a guide surface, preferably provided underneath the wrapping web.  
         [0009]     In particular, the guide unit can be arranged in edge areas of the wrapping web, where it forms a kind of directional device. Preferably, however, it extends over at least substantially the entire width of the wrapping web.  
         [0010]     If the device interacts with a blower or comprises a blower, then it is possible to provide for the latter to generate an air stream that conveys or pushes the wrapping web in the direction of the conveyance unit.  
         [0011]     If the guide unit or the channel or the guide surface interacts with the blower, then the air stream is concentrated by the channel or directed by the guide surface, whereby a targeted guidance of the wrapping web is supported. Additionally, by forming an air cushion on which the wrapping web hovers, the air stream prevents the wrapping web from contacting the channel or a wall of the channel or the guide surface and sticking there. This is particularly favorable if the wrapping web is coated with an adhesive or has adhesive characteristics. It can be provided for the blower to supply the air stream at least over substantially the entire width of the channel by means, for instance, of a supply slit or the like, which yields a uniform distribution. It is also possible for the air introduction to be done over areas or points so as to deliberately advance or lift off the channel certain areas of the wrapping web, which can also be constructed in a special manner for propulsion by an air stream, for instance, by being un-perforated, while the rest of the wrapping web is perforated.  
         [0012]     It can be provided for the wrapping web to detach after termination of the wrapping process, for instance, by having the bale continue to rotate while the feeding of wrapping web from the supply is interrupted. To achieve a uniform detachment edge and thus counteract any tangling of the wrapping web, a cutoff unit can be provided, comprising for instance a blade that cuts or detaches the wrapping web. This cutoff unit can interact with the guide unit in such a manner that the latter serves to back up the wrapping web or hold it in place.  
         [0013]     If the crop material supply unit interacts with a cutting unit, then the crop material conveyed by the crop material supply unit is further comminuted by the cutting unit, whereby a more uniform bale is formed. The crop material supply unit and the cutting unit are preferably arranged in a supply channel of the baler, through which the crop material taken up by a take-up unit reaches a baling chamber of the baler, in which the bale is formed and then wrapped.  
         [0014]     The crop material supply unit can simply be arranged adjoining the baling chamber that accommodates the bale; between the crop material supply unit and the baling chamber, it is a also possible for additional conveying units to be provided; these may be in the nature of a starter roller or in the nature of belts, which contribute to the bale formation or are provided independently thereof.  
         [0015]     The crop material supply unit can be arranged downstream of a take-up unit that takes up material to be baled from the ground. Such a take-up unit can be a conventional pick-up, for example. It is also conceivable, however, for it to be constructed in a different manner, for instance, in the nature of a conveyor belt.  
         [0016]     It is possible for the wrapping web to be brought to the crop material supply unit purely by its weight or by an air stream generated by a blower, etc, in order to begin the wrapping process, and then to be separated from the crop material supply unit by an appropriate detachment or cutoff when the baling process has been or is to be terminated. It is also possible, however, for a guide means to be provided that selectively brings the wrapping web up to the crop material supply unit. The guide means can bring the wrapping web up to the crop material supply unit so that it can be seized by the latter. After termination of the wrapping process, or in order to terminate it, the guide means removes the wrapping web from the crop material supply unit so that it is no longer conveyed by the crop material supply unit or can no longer be seized by the latter.  
         [0017]     The guide means can be constructed, for example, as a guide plate on which the wrapping web lies. If the guide means is constructed like a rake, then the wrapping web can lie on the guide means or the tines of the rake, and be brought thereby to the crop material supply unit and removed there from. Dirt and contaminants can fall between the tines of the rake, so that deposits on the guide means are counteracted. Additionally, a rake-like or partially cut-out design of the guide means offers the possibility for the wrapping web to be seized by the crop material supply unit while still lying on the guide means, which favors a good conveyance, particularly at the beginning of the wrapping process.  
         [0018]     If the crop material supply unit is arranged in a supply channel that extends between the take-up unit and the baling chamber and through which the gathered material is conveyed by the crop material supply unit into the baling chamber, then the guide means can be provided at an end area of the supply channel facing the baling chamber, or can be directly or indirectly connected to that area.  
         [0019]     The guide means can be provided to be generally movable, so as to bring the wrapping web into at least a first position separated from the crop material supply unit and a second position in which the guide means adjoins the crop material supply unit or, particularly in case of a rake-like design, engages with it. It is simple and easy to service if the guide means is provided to be pivotable. In order to pivot the guide means, it can be connected to a motor in the nature of, for example, an electric or hydraulic motor, directly or indirectly, via levers, for instance.  
         [0020]     The crop material supply unit can employ overshot or undershot conveyance. In case of overshot conveyance, wrapping web is preferably supplied from above. In case of undershot conveyance, a supply from below is favorable, where the wrapping web can be brought by the guide means from below up to the crop material supply unit so that it can be seized by the later and conveyed into the baling chamber.  
         [0021]     A device for wrapping bales can find application in industry on balers that form bales of paper, wastes, textile materials, and so on. Such a device is particularly suited, however, for use on an agricultural baler for bales of agricultural crops that is usually towed by a tractor vehicle; more particularly it is suited for round balers, since these must be structurally simple and operationally secure to survive in harvesting use. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]     An embodiment of the present invention is represented below in the drawing.  
         [0023]     The sole FIGURE shows a schematic representation of a baler with a device for wrapping a bale with a wrapping web. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]     The sole FIGURE shows a baler  10  of essentially conventional construction with baling chamber  12 . Corresponding to the present embodiments, a wrapping material supply arrangement  14  I for wrapping a bale  16  formed in baling chamber  12  with a wrapping web  18  is additionally provided.  
         [0025]     Baler  10  may be of a conventional design, that is, with a baling chamber  12  of constant or variable size that is surrounded by rollers, by chains or by a combination of belts and chains or, as in this embodiment, by belts  20 .  
         [0026]     Such a baler  10  can be employed in agriculture for forming bales  16  of crop material, such as straw, hay or grass. Usage in industrial fields is also conceivable, however.  
         [0027]     Wrapping material supply arrangement  14  I is provided in the present embodiment at the front end of baler  10 . Wrapping web  18  is supplied through a gap between two adjacent belts  20  to baling chamber  12 , where it is entrained by the rotating bale  16 . Wrapping material supply arrangement  14 , however, can also be arranged in a central area of baler  10 , or also in front of or above baling chamber  12 .  
         [0028]     By means of wrapping web  18 , bale  16  is tied up and thus prevented from falling apart after leaving baler  10 . Wrapping web  18  can be a film, a net, textile, paper or the like.  
         [0029]     Wrapping material supply arrangement  14  comprises a housing  22 , feed means that supply wrapping web  18  to bale  16 , or a feed element constructed in this example as a feed roller  24  and a cutoff unit  26 . Wrapping web  18  is stored in housing  22  as a roll  28  or a supply. Housing  22  can also be constructed such that it stores several rolls  28  and/or comprises steps or depressions for holding them in position. In the present embodiment, housing  22  comprises a flap  23  which is mounted to a location on the baler frame vertically beneath the housing  22  for pivoting about a horizontal transverse axis between an upper operating position, wherein it is joined to the remainder of housing  22  and can close off housing  22 , and a lowered loading position, shown in dashed lines, wherein the reserve supply roll can be accessed and manually placed in an operative position and wherein a new reserve roll can be loaded into the housing  22 . Flap  23  is provided with an intermediate bottom  25  that is constructed such that it provides a resting place for an additional roll  28  that can be carried along as an extra supply in baler  10 . Flap  23  can be brought manually or automatically or by motor power, with the aid, for example, of a hydraulic cylinder, in the form, for instance, of a motor or a damper, into the lowered loading position.  
         [0030]     The feed element or feed roller  24  is provided on its circumferential surface with a coating having a high coefficient of friction and can be set into rotation. Initially, the rotation helping to draw wrapping web  18  off roll  28  and, during the wrapping process, it builds up a tension in the web due to a braked rotational motion. In its operating position, roll  28  comes into contact with feed roller  24  at an area that corresponds to roughly a four to six o&#39;clock position.  
         [0031]     Additionally, wrapping material supply arrangement  14  comprises a guide unit  30  which guides wrapping web  18  in the direction of a gap  32  between adjacent belts  20 .  
         [0032]     Guide unit  30  is constructed in the form of a shallow channel  34  extending over the entire width of wrapping web  18  and closed at the sides; it extends approximately into gap  32 . Alternatively, a guide unit could be provided only underneath wrapping web  18 , for example, in the form of a guide sheet.  
         [0033]     On channel  34 , it is possible to provide one or more blowers that blow air directly or via tubes, lines, etc. into channel  34  to convey wrapping web  18  in the direction of bale  16  or to counteract adhesion of the wrapping web  18  to channel  34  by forming an air cushion in channel  34  on which the wrapping web  18  hovers, particularly if the wrapping web  18  is coated with an adhesive or is constructed to be self-adhesive.  
         [0034]     Alongside this wrapping material supply arrangement  14 , baler  10  comprises a take-up unit  36  in the nature of a conventional pickup, which takes up cut crop material from the ground and brings it into a supply channel  38 . A conveyor rotor with driving elements or a crop material supply unit  40 , which conveys the crop material supplied by take-up unit  36  into baling chamber  12 , is provided in the supply channel  38 .  
         [0035]     Crop material supply unit  40  also interacts in a conventional manner with a cutting unit  42 , which is provided in supply channel  38  above crop material supply unit  40 , but could also be positioned below crop material supply unit  40  or elsewhere. Cutting unit  42  comprises a plurality of blades  44  that penetrate the conveyance area of crop material supply unit  40  so as to comminute the crop material further.  
         [0036]     In an upper end area  46  of supply channel  38  facing baling chamber  12 , a pivotable material guide  48  is provided. The material guide  48  interacts with the wrapping web  18  brought in from channel  34  and is designed in the manner of a rake. Material guide  48  is shown in the figure pivoted down in an operating position (solid line) and in a non-operating position (broken line).  
         [0037]     The wrapping web  18  coming from channel  34  is taken up by material guide  48  at the end of channel  34 . If material guide  48  is in its lowered position, wrapping web  18  is seized by crop material supply unit  40 , employing overshot conveyance in the illustrated embodiment, and led into baling chamber  12 , where wrapping web  18  is in turn seized by rotating bale  16  so as to wrap it.  
         [0038]     If material guide  48  is in its upper, non-operating position, on the other hand, in which it or its tines are some distance away from crop material supply unit  40 , wrapping web  18  is not seized by crop material supply unit  40  and thus not brought to the bale  16 , so that no wrapping process of bale  12  takes place.  
         [0039]     The mode of operation of baler  10  or wrapping material supply arrangement  14  will be briefly summarized below.  
         [0040]     By means of supply device  36 , crop material is conveyed via supply channel  38  and crop material supply unit  40  into the baling chamber  12  of baler  10 , where it is compacted by belts  20  into a bale  16 . After the bale formation has finished, as determined, for instance, by one or more sensors detecting the bale size, a time controller, a determination of the flow amount and so on, wrapping material supply arrangement  14  is activated so as to wrap bale  16  with wrapping material  18 . This activation can be done, for example, by means of a control or regulation unit, not shown, that can be provided on baler  10  itself or on a towing vehicle such as a farm tractor. To start the wrapping process, feed roller  24  is set into rotation to pull wrapping material off roll  28 . Wrapping material  18  moves into channel  34  and is conveyed by the action of the feed roller  24  and the above-described blower action, if present, in the direction of baling chamber  12  or bale  16 . Additionally, material guide  48 , which is actively connected to an electric motor or a hydraulic motor, is brought into its lowered position, shown with a solid line, in which it becomes engaged with the crop material supply unit  40  or is positioned adjacent thereto. The wrapping web  18 , which emerges from channel  34  and is now lying on the material guide  48 , is brought by crop material supply unit  40  between adjacent belts  20  into baling chamber  12 , where it is seized by rotating bale  16  and becomes wrapped about the bale. It can be advantageous to deactivate take-up device  36  during the wrapping process, or in general to inhibit a supply of crop material to crop material supply unit  40  to guarantee an optimal feeding of the wrapping web  18 .  
         [0041]     If the wrapping process of bale  16  has terminated, which can be determined by conventional sensors or also by a timer controller, etc., wrapping web  18  is cut through by means of a cutoff unit  26  pivotably arranged on channel  34 , and material guide  48  is brought back to its raised position (broken line) and thus wrapping material  18  is brought out of engagement with crop material supply unit  40 , whereby no further wrapping material  18  is supplied to baling chamber  12 .  
         [0042]     Subsequent thereto, the finished bale  16  is ejected from baler  10 .  
         [0043]     It is pointed out here that the use of material guide  48 , or of a material guide  48  constructed in the form of a rake, is not absolutely necessary to the invention. Rather, it is possible to forgo material guide  48  entirely, particularly with a suitable controlling of feed roller  24  for pulling the wrapping web off roll  28  and/or a suitable arrangement of cutoff unit  26 .  
         [0044]     In a second embodiment, the present invention is used with a crop material supply unit employing undershot conveyance. For this purpose, the wrapping material is supplied in an area situated essentially below baling chamber  12  in order to be seized by it as described above and brought to the bale, so that the wrapping material can be seized by the bale. To guide the wrapping material up to the crop material supply unit in this manner, one or more blowers, for example, can be used in the manner described in the first embodiment. The use of mechanical supply means in the nature of supply means engaging with the wrapping web, such as additional rotors, belt conveyors, etc. is also conceivable. For such an embodiment it is advantageous if the opening through which the wrapping web reaches the crop material supply unit is at least substantially closed during the actual formation of the bale so as to counteract the intrusion of crop material.  
         [0045]     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.