Abstract:
A large round baler has an expansible baling chamber defined, in part, by a plurality of side-by-side mounted belts that act to roll up crop to form a bale within the chamber. The baler is equipped with a twine wrapping arrangement which leaves loose twine ends adjacent one of the ends of the wrapped baler. In order to secure these loose ends, there is provided an adhesive tape dispensing arrangement, which cooperates with the bale-forming belt that is aligned with the area of the bale on which the loose twine ends lie, so that a length of adhesive tape is selectively fed into the bale chamber by the bale-forming belt such that it is wrapped about the bale in covering relationship to the loose twine ends. A separating arrangement is provided for causing that part of the length of adhesive tape that is wrapped about the bale to be separated from the supply roll of tape.

Description:
The invention concerns an arrangement for securing a loose twine end on a cylindrical bale by means of a self-adhering tape. 
     BACKGROUND OF THE INVENTION 
     DE-A-41 32 664 discloses a large round baler with a twine wrapping arrangement and an arrangement for securing a twine end lying on a circumferential surface of the cylindrical bale. The twine end is secured according to an embodiment by using a tape that may be configured as adhesive and that is conducted by means of two supply rolls and a guide vane to an inlet slot for the harvested crop. There the tape is grasped by the rotating bale and wrapped around it. 
     EP-A1-0 820 691 discloses a large round baler equipped with a net wrapping arrangement wherein a net guide surface of the arrangement is brought into contact with a rotating member or members of the bale-forming chamber so that the rotating member or members carries the net material into the baling chamber for being wrapped about the bale. The problem of loose twine ends is not applicable to a net wrapping operation. 
     DE-A1-27 05 101 discloses an arrangement that makes it possible to simultaneously wrap twine and bands of plastic sheet material about a cylindrical bale, where the twine may be located underneath as well as on top of the plastic sheet material. This sheet material, that can also be supplied in one layer over the entire width of the bale, is not capable and is not intended to secure the loose twine ends, but is used to cover the outer surface of the bale so as to protect it from the weather. Plastic sheet bands and loose yarn ends could unwrap together from the bale. 
     The problem underlying the invention is seen in the fact that, in the prior art, the tape supply rolls must be driven independently which results in an increased cost. 
     SUMMARY OF THE INVENTION 
     According to the present invention, there is provided an arrangement for securing twine ends on the circumference of a cylindrical bale, with the tape being conducted to the bale by an arrangement which represents an Improvement over that disclosed in DE-A-41 32 664. 
     An object of the invention is to provide an arrangement for applying adhesive tape to loose twine ends of twine wrapped about the bale by making use of a conveying element that is already present 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a right side elevational view of a large round baler of the type with which the present invention is particularly adapted for use. 
     FIG. 2 is a right rear perspective view, showing the rear region of the round baler with an arrangement for securing a loose twine end on a cylindrical bale. 
     FIG. 3 shows a schematic view of the arrangement according to FIG. 2, with the arrangement being shown in an operating position. 
     FIG. 4 is view like that of FIG. 3, but showing the arrangement in a non-operating position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows a large round baler  10  with a housing  12  supported on wheels  16  and that can be coupled to an agricultural tractor, not shown, by a towbar  14 . The housing  12  is composed of a rigid, front housing section  18  and a rear housing section  20  that is pivotally attached to an upper rear location of the housing section  18  so that the rear section forms a discharge gate which may be elevated to permit a completed bale to be discharged onto the ground. The housing  12  contains a multitude of rolls of which lower rear and front rolls  24  and  26 , respectively, of the rear housing section  20  are shown. Several endless conveying elements  28  extend over the rolls and are arranged alongside each other, the elements largely surrounding a region between opposite side walls  30  of the housing  12  so as to cooperate with the latter to form a baling chamber  44 . In this embodiment, the conveying elements  28  are configured as belts. In the lower region of the baling chamber  44 , an inlet  34  is provided, that is bordered to the rear by the roll  26  and that admits crop taken up by a pick-up  36  into the baling chamber  44 . On a rear wall  38  of the rear housing section  20 , a net wrapping arrangement  39  is provided. The net wrapping arrangement  39  includes opposite support walls  40  fixed to the rear housing section rear wall  38  and supporting a net material supply roll  41 , with a length of net material  43  here being shown introduced into the baling chamber  44  and wrapped around, and over the ends of, a cylindrical bale  47  formed in the baling chamber  44 . The wrapped length of net material  43  is shown in a condition just before it is severed from the supply roll  41 , after which the end portion extending between the bale and severing device will be wrapped upon the bale, with the wrapped net then serving to prevent the bale  47  from falling apart after being discharged from the baling chamber  44 . 
     Underneath the towbar  14 , there is shown a portion of a twine wrapping arrangement  32  for wrapping a formed bale with twine in lieu of net so as to bind the bale together. In this embodiment, the arrangement  12  is configured in such a way that the last twine windings are deposited on the left side of the cylindrical bale, as viewed from behind facing in the direction of forward travel. The round baler  10 , as described so far, is already known in the state of the art and hence does not require any further description. 
     Referring now to FIG. 2, there is shown mounted to the rear of the rear housing section  20  an arrangement  42  for securing loose twine ends on the surface of cylindrical bales formed in the baling chamber  44  by using; adhesive tape, it being noted that all but the support walls  40  of the net wrapping mechanism  39  has been removed. Among other items, the arrangement  42  includes a tape supply roll carrier  46 , a fastening material guide structure  48 , a positioning shaft  50 , front and rear fastening material feed rolls  51  and  52 , respectively, and an adhesive tape separating or severing device  54 . 
     While the arrangement  42  is shown in connection with a large round baler having an expansible baling chamber, it is to be understood that, as a deviation from this, the arrangement  42  can also be provided on a large round baler having a fixed baling chamber and can be placed at a location other than the rear of the baling chamber. Further, it is to be understood that the invention could be applied to balers having, in place of bale forming belts, chains or rolls. 
     The roll carrier  46  is configured as a rigid axle and is retained in support walls  58  that are fixed on the rear wall  38 . Received on the roll carrier  46  is an adhesive tape supply roll  60 , where a brake  62 , for example in the form of a cone mounted on the roll carrier and spring-loaded against an end of a core of the roll  60 . The brake  62  operates, on the one hand, to prevent the roll  60  from rotating freely on the roll carrier  46  and, on the other hand, to fix the location of the roll  60  on the roll carrier  46  in the sideways direction. If desired, a second brake  62  could be mounted on the roll carrier so as to bear against the opposite end of the core of the roll  60 . In the embodiment shown, the roll carrier  46  is located above the net wrapping arrangement  40 . As a deviation from this, the roll  60  could be supported in bearings on an axle that could be present for a net roll. Furthermore, the roll carrier  46  extends over the entire width of the baling chamber  44 , so that a length of tape  64  (FIGS. 3 and 4) may be supplied at every location along the length of a cylindrical bale formed in the baling chamber  44 . However, fundamentally, it is sufficient if the roll  60  is supported in bearings located so that the roll  60  is aligned fore-and-aft either with the side or the center of the formed cylindrical bale. The roll  60  contains a large amount of thin, elastic, durable and adhering tape  64 . The fixing can be attained: by a bonding agent applied to one or both sides of the tape  64  or by adhesion. 
     The guide structure  48  is configured as an inverted U, whose legs  66  extend downward and contain a bottom  68  between them. The side of the bottom  68  facing the conveying element  28  defines a guide surface  69  which is very smooth so that it offers very low frictional resistance. The frictional resistance can be further reduced by the application of another material to the bottom  68 , for example, PTFE, that is, Teflon, so as to define the surface  69 . The guide structure  48  extends generally from under the lower front discharge gate roll  26  to the rear wall  38  so that it also passes beneath the lower rear discharge gate roll  24 . The forward region of the guide structure  48  is supported by a bearing  70  so as to pivot vertically on a transverse support  72  of the rear housing section  20 . In its rear end region, the guide structure  48  extends above and beyond the positioning shaft  50  and is provided at its ends with two arms  74  in which the pair of rolls  51  and  52  are supported, free to rotate. The position of the guide structure  48  is selected in such a way that the guide surface  69  it is in vertical alignment with the leftmost conveying element  28  and is in fore-and-aft alignment with the tape supply roll  60 . In the region of the separating arrangement  54 , the bottom  68  of the guide structure  48  is provided with openings, not shown. 
     In this case, the positioning shaft  50  extends underneath the rear housing section  20  and over its entire width. To support it and permit it to pivot freely, bearings  76  are provided at the underside of the side walls  30 . On the right side, as seen in the direction of operation, a lower end of a lever arm  78  is fixed the an end of the positioning shaft  50 , with an upper end of the lever arm  78  being provided with a fork  80 . In the region of the guide structure  48  and between the legs  66 , two arms  82  are attached, preferably welded, radially to the positioning shaft  50 . At their free ends, the arms  82  carry rolls  84 , that are in contact with the underside of the bottom  68 . 
     Free rotation of the pair of rolls  51  and  52  is accomplished by first and second pairs of bearings respectively located at fore-and-aft spaced positions, that are relatively close to each other, in the arms  74 . The positions are selected in such a way that the front roll  51  can be brought into contact with the lower rear baler belt-support roll  24 , while the rear roll  52  is used to alter the direction of the tape  64 . One or both of the rolls  51  and  52 , if desired, can be configured as a spreader roll that extends the tape  64  in its width as it runs over the rolls. The fastening of the pair of rolls  51  and  52  by means of the arms  74  guarantees that the rolls move in unison with the guide structure  48 . 
     The separating arrangement  54  is provided with a transverse rail  86  that extends underneath and cross ways to the length of the guide structure  48 . Several pointed pins  88  that extend vertically are attached to the rail  86 , which can extend through the aforementioned openings in the bottom  68  of the guide structure  48 . The length of the pins  88  is selected in such a way that they extend through the openings and end above the tape  64  when the guide structure  48  is located in a lower, pause or non-operating position, while they extend into the interior of the U-shape when the guide structure  48  is moved towards the conveying element  28 . In place of the generally needle-shaped pins  88 , serrations, teeth or the like could be provided with which it is possible to perforate the tape  64  so that it tears when it is penetrated. In view of the tension applied by the cylindrical bale to the tape  64 , the pins  88  must be able to absorb high bending moments when they penetrate the tape  64 . 
     In place of a rigid separating arrangement  54 , an adjustable one could be employed, and in place of the pins  88  a cutter could be used. 
     In the embodiment shown, the actuating arrangement  56  is configured as an electric motor that is supported in bearings at one end In the side wall  30  and at the other end in the fork  80 , free to pivot. An electric motor has the, advantage that it can be controlled easily; nevertheless it would also be possible to use a hydraulic or a pneumatic motor. Beyond that, a purely mechanical operation could also be performed. The actuating arrangement  56  can be extended or retracted so as to act through the lever arm  78  and, thereby, pivot the positioning shaft  50 . The control or regulation is performed through an arrangement, not shown, in which, for example, signals can be included concerning the wrapping process by means of the twine wrapping arrangement  32  and the position of the rear housing section  20 . 
     The tape  64  is prepared, in the following manner, for being dispensed. The tape supply roll  60  is slid onto the roll carrier  46  and the roll carrier  46  is secured to the supports  58 . Following this, the brake(s)  62  is (are) mounted onto the roll carrier  46  so as to properly locate the roll  60  and, by virtue of the spring-loaded cone(s), for example, prevent a free rotational movement of the roll  60 . Following this, the tape  64  is pulled off the roll  60  and laid around the underside of the rear tape guide roll  52  and finally over the upper side of the front roll  51 , so that an end of the tape  64  comes to lie in the gap between the guide surface  69 , of the bottom  68 , and the underside of the conveying element  28 . 
     After all that, the system operates as follows, where initially the tape  64  is assumed to have been prepared for being dispensed in the manner described above. 
     After the twine wrapping process is completed by the twine wrapping arrangement  32 , one or more loose twine ends lie on the left end region of the cylindrical bale, specifically in the area which is in fore-and-aft alignment with the tape  64 . The aforementioned control arrangement receives a signal and extends the actuating arrangement  56  so that the latter acts through the lever  78  so as to rock the positioning shaft  50  and arms  82 . Since the arms  82  or their rolls  84  are in contact with the underside of the bottom  68  of the guide structure  48 , the guide structure is raised and the guide surface  69 , and/or the front roller  51 , is pressed, along with the tape  64  lying on it, against the underside of the moving conveying element  28 . Due to the high frictional contact between the tape  64  and the conveying element  28 , on the one hand, and the low friction on the guide structure  48 , on the other hand, the tape  64  is carried along with the conveying element  28  to the baling chamber inlet  34  where it extends around the roll  26  and reaches the nip formed between the cylindrical bale and the conveying element  28 . The cylindrical bale engages the tape  64  and, due to the rotation of the bale, wraps the tape about the circumference of the bale in the region of the previously wrapped loose twine ends. After more than one revolution, the second layer of the tape  64  is deposited upon the first layer and adheres on the basis of adhesion or the bonding agent, so that the loose twine ends are secured. As soon as a secure adhesion of the tape layers is assured, the guide structure  48  is again lowered whereby the pins  88  extend through the openings in the bottom wall  68 , the tape  64  then being lowered onto the pins  88 . As soon as the tape  64  is penetrated by the pins  88 , the downstream part, which is under tension, tears off, while the part connected to the supply roll  60  is retained by the pins  88 . Since the roll  60  does not overrun or barely does so by reason of the brake  62 , it stops immediately.