Bundling system for forming packages, bundling machine and method of bundles

Abstract

The bundling system comprises a frame which is attachable to and pullable by a tractor, a bundling chamber of bales arranged on the frame to form bales of packages in vertical arrangement along the longitudinal direction of the packages, a pushing device arranged to insert a bale into the bundling chamber, a platform for lifting the bale mounted displaceable in vertical direction within the bundling chamber, and holding means for holding the bale in an upper position. The pushing device comprises a compression surface adapted to exert an active compression force on the layers of the bale in the transverse direction of the packages within the bundling chamber, such that the compression surface exerts an active compression force on the layers of the bale while the lifting platform moves the layers in vertical direction within the interior space of the bundling chamber.

Description

TECHNICAL FIELD

[0001] The present invention relates to a baling system for forming bales of forage or similar material, wherein the bales comprise a plurality of layers of bales and said bales have a predetermined nominal width "A". The present invention also relates to a baling machine adapted to bale bales having a nominal length "L" comprised between 750 mm and 1200 mm. Finally, the present invention also relates to a method for forming bales of forage or similar material, which are vertically arranged along the longitudinal direction "Y" of the bales on the frame of a baling machine. BACKGROUND

[0002] Baling machines for bales of forage or similar material are known, which are of the type that group the bales so as to form a vertical bale of bales inside a baling chamber, which is vertically arranged on the frame of the machine. The main advantage of these machines is that they have a very small length, unlike other types of machines that collect the bales so as to form a bale that extends horizontally on the frame.

[0003] The machines that form vertical bales of bales, such as for example the one described in patent EP 1 222 850 A1, group the bales according to a baling system that comprises pushing means arranged to insert the bales through a bale inlet of the baling chamber into the baling chamber, a vertically displaceable lifting platform of the bales, which is mounted to displace the bales inside the baling chamber from a lower position to an upper position, and holding means for holding the bales in the upper position when the lifting platform resumes the initial lower position of the lifting platform.

[0004] According to the baling system described in the above-mentioned patent, the conveying means move the bales one after the other from a loading mouth to the inlet of the baling chamber, where the pushing means introduce the layer of bales that arrives into the internal space of the baling chamber. Subsequently, the lifting platform vertically displaces the bales of each layer that arrives to the upper position, where the holding means hold the layer so that the lifting platform can resume the lower position of the lifting platform, waiting for the reception of a new layer of bales. When the loading cycle of the layers of the bale ends, the lifting platform holds the group of bales superimposed inside the chamber to allow the binding of the bales. Then the rear door of the baling chamber is opened and, while the tractor travels, the pusher element serves to release and place the bales on the ground. Subsequently, the bale of bales placed on the ground is collected and stored for transport by truck or container.

[0005] In practice, the drawback of the tying systems described in the aforementioned patents is that they are not able to provide a sufficiently compact package of bales, which has a firm and tight tie so as to facilitate handling of the package and which minimizes the risk of the package coming loose when handled.

[0006] In practice, although it is known that the width of the internal space of the tying chamber forming the package is expected to conform as much as possible to the value obtained by the sum of the nominal widths "A" of the bales in the layer, in practice this is not possible because, when the actual width of the bales is greater than the nominal width, for example due to excessive humidity of the plant material or due to the bale size varying according to the baler, the lifting platform has difficulty in moving the bales vertically to the upper position. In practice, the dimensions of the internal space of the tying chamber are not accurately designed to facilitate the displacement of the layers of bales in the vertical without having to take into account the humidity, the type of plant material or the size of the bales. However, this results in a package of bales which is not very compact.

[0007] In view of the above, there is a clear need to obtain a tying system of bales which makes it possible to form a compact package of bales which facilitates subsequent handling on site, thus minimizing the risk of the package coming loose and facilitating optimization of the space occupied by the package during transport. SUMMARY

[0008] The aim of the present application is to solve the aforementioned drawbacks by providing a tying machine of bales having the advantages which will be described hereinafter.

[0009] According to this aim, in a first aspect, the present application provides a tying system of bales for forming a package of bales of forage or similar material, wherein the package comprises a plurality of layers of bales and said bales have a predetermined nominal width "A", the tying system comprising:

[0010] - a frame which can be attached to and towed by a tractor,

[0011] - a receiving surface of bales located on the frame,

[0012] - a tying chamber of bales arranged on the frame to form a package of bales arranged vertically along a longitudinal direction "Y" of the package, said tying chamber comprising an inlet of bales arranged in correspondence with the receiving surface of bales,

[0013] - a pushing device arranged to introduce a bale through the inlet of bales of the tying chamber into the tying chamber,

[0014] - a vertically displaceable bale lifting platform, which lifting platform is mounted to displace the bale in the bundling chamber from a lower position to an upper position, and

[0015] - a holding device for holding the bale in the upper position when the lifting platform resumes the initial lower position of the lifting platform.

[0016] The bundling system is characterized by the fact that;

[0017] - the pushing device comprises a compression surface adapted to exert a compression force on the layers of the bale in the transverse direction "X" of the package, preferably against the rear wall of the bundling chamber,

[0018] - wherein the system comprises processing and control means configured to send a compression signal to the actuating device associated with the compression surface to exert a compression force on the layers of the bale by the compression surface when the lifting platform vertically displaces the layers of the bale in the interior space of the bundling chamber.

[0019] According to a second aspect, the invention provides a method for forming a baled package of a bale of forage or similar matter, which bale of forage or similar matter is placed vertically along the longitudinal direction "Y" of the package on a frame of a baling machine for the bale, wherein the package comprises a plurality of layers of the bale, and wherein the method comprises the steps of:

[0020] a) introducing the layers of the bale into a bundling chamber of the bale,

[0021] b) exerting a compression force on the layers of the bale in the transverse direction "X" of the package by a pushing device comprising a compression surface adapted to exert a compression force on the layers of the bale and against the rear wall of the bundling chamber, and

[0022] c) vertically displacing the layers of the bale to an upper position by means of a vertically displaceable lifting platform mounted in the bundling chamber when performing arrangement b).

[0023] According to a third aspect, the invention provides a baling machine for forming a package of a bale of forage or similar matter having a nominal length "L" comprised between 750 mm and 1200 mm, the baling machine comprising the claimed bundling system.

[0024] For one embodiment, the strapping machine comprises a change kit for adjusting the width "a" of the internal space of the strapping chamber. In particular, the change kit is for adjusting the width "a" of the internal space of the strapping chamber to form a package of bale packages having the following layers: each layer is formed by a number of bale packages each having a nominal width "A" equal to or greater than 500 mm, for example to form a package of bale packages having the following layers: each layer is formed by two bale packages each having a nominal width "A" of 560 mm. Alternatively, the change kit allows adjusting the width "a" of the internal space of the strapping chamber to form a package of bale packages having the following layers: each layer is formed by three or more bale packages each having a nominal width "A" equal to or less than 500 mm, for example to form a package of bale packages having the following layers: each layer is formed by three bale packages each having a nominal width "A" of 460 mm.

[0025] Advantageously, the change kit comprises a bale package lifting platform extension that can be attached in a removable manner to an already existing bale package lifting platform and a rear wall of the strapping chamber that is mounted in a displaceable manner on at least one pair of slides, so as to be able to adjust the width "a" of the internal space of the strapping chamber according to the nominal width "A" of the bale packages of the layers of bale packages forming the package.

[0026] In the present invention, the pushing device that inserts the layers of bale packages into the strapping chamber comprises a compression surface that is adapted to exert an active compression force on the layers of bale packages along the transverse direction "X" of the package and against the rear wall of the strapping chamber while the lifting platform displaces the layers to the upper position. Thus, the width "a" of the internal space of the strapping chamber can be designed with an adjusted value without having to worry about the humidity of the plant material or the size of the bale packages that can cause problems when vertically moving the layers of bale packages.

[0027] In fact, it has been observed that by actively compressing the layers transversely against the rear wall of the strapping chamber while the lifting platform moves the layers to the upper position, the width "a" of the strapping chamber can even be less than the value obtained by the sum of the nominal widths "A" of the bale packages forming the layers, without there being a risk of the dimensions of the strapping chamber being insufficient, for example in the case of the humidity of the plant material not being the desired humidity or the actual width of the bale packages being greater than the nominal width "A". In addition, it has been observed that by reducing the dimensions of the strapping chamber, the walls of the chamber itself passively compress the layers when the lifting platform resumes the initial position of the lifting platform. Thus, a very compact package is obtained with a very low risk of becoming loose, and the space occupied by the package is significantly optimized to facilitate the transport of the package.

[0028] Preferably, according to the implementation of the strapping system, the handling and control means, for example a handling and control unit, are configured to send a compacting signal to the bale lifting platform to exert an active compression force on the bales along the longitudinal direction "Y" of the package at the end of the loading cycle of the bales in the package.

[0029] Therefore, for example, at the end of the loading cycle, when the lifting platform vertically displaces the last layer of bales, the lifting platform exerts a longitudinal active compression force on the bales, thus allowing the packages of the superimposed bales located inside the strapping chamber to be vertically compacted.

[0030] Advantageously, the internal space of the strapping chamber comprises a width "a" in the transverse direction "X" of the package equal to or less than the value obtained by the sum of the nominal widths "A" of the bales of a layer. For example, the width "a" of the strapping chamber can be designed to have a value of 880 mm, which is less than the 920 mm resulting from the sum of the nominal widths "A" of 460 mm of the two bales forming the layer.

[0031] In this way, when the bales lose contact with the compression surface of the pushing device, the front and rear walls of the strapping chamber themselves are able to exert a passive compression force on the bales along the transverse direction. In this way, the claimed system makes it possible to obtain a package that is very compact both in the transverse direction and in the longitudinal direction of the package. The passive compression force exerted by the front and rear walls of the strapping chamber limits the transverse expansion of the package when the lifting platform exerts the active compression force at the end of the loading cycle. Therefore, the breaking of the strips of the bales, which often occurs in the systems of the prior art, is avoided.

[0032] Preferably, the compression surface of the bales comprises a pushing plate sized to provide a contact surface with the bales equal to or greater than 150 cm 2 , advantageously sized to provide a contact surface comprised between 800 cm 2 and 5000 cm 2 , which is adapted to provide the above-mentioned active compression force on the bales along the transverse direction "X" of the package, wherein preferably the active compression force applied to the layer of bales is comprised between 0.05 Kg / cm 2 and 1.5 Kg / cm 2 .

[0033] Still preferably, the driving means of the pushing plate comprise a parallelogram mechanism and the pushing plate is attached in a hinged manner to a pair of pivoting arms of the parallelogram mechanism. The parallelogram mechanism allows the plate to be displaced in such a way as to remain in a substantially vertical position inside the strapping chamber, thus maximizing the contact surface with the bales throughout the stroke.

[0034] According to a preferred embodiment, the parallelogram mechanism is mounted so that the pivoting arms and the pusher plate are suspended above the receiving surface of the bale, the articulation of the parallelogram mechanism being such that the pusher plate can oscillate above the receiving surface of the bale and remain in contact with the bale to displace the bale horizontally and the pusher plate exerts an active compression force in the transverse direction "X" within the baling chamber.

[0035] Advantageously, the end of the pivoting arm is attached to and rotatably articulated to a respective pivoting shaft, the pivoting shaft being arranged so that a lateral projection lying in the plane of the parallelogram mechanism represents that said pivoting shaft is aligned according to an inclined line forming an acute angle with the horizontal plane.

[0036] In the present invention, the pusher plate actuated by the parallelogram mechanism oscillates by 120° with respect to the receiving surface of the bale, thus remaining in a substantially vertical position and in contact with the bale. The pivoting shaft of the pivoting arm of the parallelogram mechanism is mounted so that the arm can be stowed in a rear position, so that the bale can be positioned opposite the inlet of the baling chamber. In the forward position, the pusher plate penetrates into the baling chamber while remaining in contact with the bale.

[0037] According to one embodiment, the baling chamber comprises a rear wall, wherein at least one portion of the rear wall of the baling chamber defines a bale unloading door, the system comprising fixing means for preventing the unloading door from opening when the pusher surface exerts a compression force on the bale and against the rear wall of the baling chamber. Advantageously, according to one embodiment, the fixing means comprise:

[0038] - at least one unloading door fastening member,

[0039] - a force multiplier mechanism associated with the fastening member, and

[0040] - a fluid power element or electromechanical device arranged to actuate the force multiplier mechanism.

[0041] In this way, the fastening member serves to prevent the unloading door from opening when the pusher surface exerts an active compression force on the bale and against the rear wall of the baling chamber. The electromechanical device can comprise, for example, a motor or a magnetic interlock.

[0042] According to a preferred embodiment, the system comprises an adjustment mechanism for adjusting the width "a" of the baling chamber based on the nominal width "A" of the bale of layers to modify the width "a" of the internal space of the baling chamber.

[0043] Therefore, the system is suitable for use with bale packages having different nominal widths "A", for example the system is suitable for use with bale packages having a nominal width "A" of 440 mm, 460 mm or 490 mm. Therefore, depending on the nominal width "A" of the bale package, the user can adjust the width "a" of the strapping chamber so that the passive compression force applied to the plant material of the package is optimal. Table 1 shows, by way of example, the reduced width "a" of the strapping chamber suitable for applying a passive compression force to the layers of the bale package, as a function of the nominal width "A" of the bale package.

[0044] Table 1. Reduced width "a" of the strapping chamber for the layers formed by two bale packages, as a function of the nominal width "A" of the bale package, to apply a passive compression force to the layers of the bale package.

[0045]

[0046]

[0047] Preferably, the processing and control means, for example a processing and control unit operatively connected to the strapping system of the bale package, are configured to send a compacting signal to the actuation means for actuating the compression surface so that the compression surface applies a predetermined active compression force value based on the value of the width "a" of the internal space of the strapping chamber.

[0048] According to one embodiment, the adjustment mechanism comprises a rear wall of the strapping chamber mounted in a displaceable manner on at least one pair of guides to be able to adjust the width "a" of the internal space of the strapping chamber as a function of the nominal width "A" of the bale package and / or the moisture content of the material of the bale package.

[0049] Preferably, the rear wall of the strapping chamber comprises: a rear wall portion acting as a rear unloading door of the package, wherein said rear wall portion is mounted to pivot clockwise on at least one pair of slides mounted in a displaceable manner on at least one pair of lower guides; and a rear wall portion acting as an upper door, wherein said rear wall portion is mounted to pivot counterclockwise on at least one pair of slides mounted in a displaceable manner on at least one pair of upper guides.

[0050] Optionally, for the embodiment of the strapping machine comprising a change kit for adjusting the width "a" of the internal space of the strapping chamber, the change kit comprises:

[0051] - a bale package lifting platform extension which can be attached in a removable manner to an already existing bale package lifting platform,

[0052] - a first pair of slide extensions, which can be attached in a removable manner to the existing at least one pair of slides mounted in a displaceable manner on the pair of lower guides, wherein said rear wall portion, which acts as a lower unloading door, is mounted to pivot clockwise on said first pair of slide extensions, and

[0053] - a second pair of slide extensions, which can be attached in a removable manner to the existing at least one pair of slides mounted in a displaceable manner on the pair of upper guides, wherein said rear wall portion, which acts as an upper door, is mounted to pivot counterclockwise on said second pair of slide extensions.

[0054] Therefore, by means of the claimed system, the rear wall of the chamber itself defines both the lower unloading door and the upper unloading door. Moreover, the width "a" of the strapping chamber can be adjusted and / or adapted to form a package comprising a layer of bale pieces having a nominal width "A" selected from the range between 440 mm and 560 mm.

[0055] The closing of the two doors is ensured by means of fixing means which act by preventing the opening of the doors, so that the two doors can withstand the active compression force of the compression surface of the pushing device.

[0056] Advantageously, the fixing means comprise at least one fluid power element or electromechanical device arranged to actuate a force multiplier mechanism associated with the fastening members of the two doors, for example at least one fastening member configured to act as a peg. Preferably, said fluid power element or said electromechanical device is mounted displaceable along the transverse direction "X" of the package, so as to adapt the position of the fixing means to the width "a" of the strapping chamber. For example, one end of the fluid power element can be mounted displaceable on a side wall of the strapping chamber by means of a threaded rod mechanism.

[0057] As discussed, the system comprises holding means for retaining or holding the bale piece in the upper position when the lifting platform resumes the initial lower position of the lifting platform. According to an embodiment, the holding means comprise a bale piece holding device hingedly attached to a wall of the strapping chamber, preferably to the rear wall of the chamber, the holding device comprising at least one holding member for holding the bale piece in the upper position, wherein said holding member is associated with a parallelogram mechanism, which when actuated, the holding member can be displaced linearly along the transverse direction "X" of the package to hold the bale piece inside the strapping chamber.

[0058] Thanks to these characteristics, the retaining members acquire a deployment position in which they can contact the bale inside the bundling chamber laterally and uniformly, thus providing the best tightening of the package when the machine travels on an irregular surface of the site.

[0059] Advantageously, the system comprises processing and control means, for example a processing and control unit, configured to send a package retaining signal to the actuation means associated with the retaining device, so that the retaining members move linearly by a predetermined distance based on the value of the width "a" of the internal space of the bundling chamber.

[0060] Preferably, the system comprises a plurality of binding units distributed in alignment in correspondence with the bale inlet of the bundling chamber, each of the binding units being able to provide a turn of twine on the package of the bale, the system comprising at least one element acting as a pivot and arranged adjacent to the binding units outside the bundling chamber to direct the turn of twine on the package from outside the bundling chamber according to an upward trajectory "T" inclined with respect to the surface of the package.

[0061] It has thus been observed that the binding operation of the package is improved, since the inclined portion of the trajectory facilitates the tensioning of the twine, so that the binding operation is performed by making the twine adhere to the package in the best way.

[0062] According to one embodiment, the system comprises: four binding units distributed in alignment in correspondence with the bale inlet of the bundling chamber to be able to bind the package formed by the bale of nominal length "L" equal to or greater than 750 mm, for example the package formed by the bale of nominal length "L" comprised between 750 mm and 900 mm, by means of four turns of twine; and a fifth binding unit distributed in alignment with the four binding units to be able to bind the package formed by the bale of nominal length "L" equal to or greater than 1000 mm, for example the package formed by the bale of nominal length "L" comprised between 1100 mm and 1200 mm, by means of five turns of twine.

[0063] It has been observed that the system of the present application is also optimal for handling bales of nominal length "L" greater than 1000 mm, which requires the application of a fifth strip or fifth turn of twine on the package. The systems of the prior art have difficulties in handling bales of this nominal length "L", since the application of the fifth turn entails a greater risk of overturning of the layer when it is introduced into the binding chamber and moved to the upper position. In the claimed system, the compression surface of the pushing device holds the bale and prevents the overturning of the layer, so that the compression surface actively compresses the bale against the wall of the binding chamber when the lifting platform vertically displaces the bale to the upper position.

[0064] Preferably, the binding system comprises an ejector device of the packages of the bale, which is provided with a plurality of ejector members, preferably at least four ejector members of the bale, wherein said ejector members each comprise a first member portion associated with the front wall of the binding chamber and a second member portion associated with the upper wall of the binding chamber, the second member portion of each of the ejector members being attached to the upper wall of the binding chamber in a hinged manner, so that when the ejector device is actuated, the set of ejector members pivots with respect to the front wall and the upper wall of the binding chamber, with removal of the packages.

[0065] The present application provides a binding system and method for forming bales of forage or similar material, which greatly improves the systems and methods already known in the prior art, allowing to obtain very compact bales formed by bales which can be from 750 mm to 1200 mm in nominal length "L", advantageously allowing to obtain very compact bales formed by bales which can be from 600 mm to 1350 mm in nominal length "L" of each bale, in different embodiments of the binding system and method.

[0066] The layer of packages can be formed by two or more bales, on which an active compression force is exerted by means of the plate of the pushing device along the transverse direction of the packages and against the rear wall of the binding chamber. Therefore, the width "a" of the internal space of the binding chamber can be designed with very tight values, which can even be lower than the value obtained by the sum of the nominal widths "A" of the bales forming the layer, without the risk that the dimensional variations of the bales when their actual width is greater than the nominal width "A" prevent the layer of bales from being introduced into the binding chamber.

[0067] At the end of the loading process, the lifting platform can exert an active compression force on the layer of bales in the longitudinal direction "Y" of the package, without causing the rope or twine to break due to the lateral expansion of the plant material, since the front and rear walls of the baling chamber themselves exert a passive compression force on the layer of bales when the width "a" of the baling chamber is less than the sum of the nominal widths "A" of the bales forming the layer and the value obtained. It has been observed that this passive compression force to which the layer is subjected facilitates the binding operation and significantly reduces the risk of the package coming loose during the subsequent handling in the field, and also optimizes the space occupied by the package during transport. BRIEF DESCRIPTION OF DRAWINGS

[0068] In order to better understand the description made herein, a set of drawings is provided, in which a number of practical cases of embodiments are schematically and purely by way of non-limiting example.

[0069] Figure 1 is a perspective view of an embodiment of a baling machine for forming packages of bales of forage or similar material, incorporating the claimed baling system. The embodiment comprises a conveying device provided with a chain-type traction disc for displacing the bales from a loading gate to a bale-receiving surface positioned opposite the inlet of the baling chamber.

[0070] Figure 2 is Figure 1 is a perspective view of another embodiment of a baling machine of the type

[0071] Figures 3 to 7 is Figure 1 is a schematic cross-section of a baling machine of the type Figure 7 shows the retaining means of the bales in the articulated manner attached to the rear wall of the baling chamber, in the active position when the lifting platform recovers the initial position of the lifting platform, thus retaining the layer of bales in the upper position.

[0072] Figures 8 to 10 is Figure 1 is a schematic cross-section of a baling machine of the type Figure 9The lifting platform is shown in its active position, thus exerting an active compression force on the bale along the longitudinal direction "Y" of the packages, to compress the packages in the vertical direction. Figure 10 The needle that binds the turn of cord is shown in the raised position, ready to perform the binding operation on the packages. The Figure 10 The complete round of cord on the bale of packages and the element that acts as a pivot to guide the round of cord along an upward trajectory "T" inclined with respect to the surface of the packages from the outside of the binding chamber is shown.

[0073] Figure 11 And Figure 12 is Figure 1 a schematic side view of the binding machine, showing the binding chamber adjusted to two different working widths "a". Figure 12 The binding chamber is shown with a greater working width "a", when the rear wall has been displaced horizontally on the guide. In the figure, the fixing means are shown, which prevent the unloading door of the packages associated with the rear wall of the binding chamber from opening.

[0074] Figure 13 is a schematic perspective view of the part of the rear wall of the binding chamber that acts as a lower section of the binding chamber. The lower section is mounted in a pivoting manner on a pair of slides that can be moved on a lower guide.

[0075] Figure 14 is a perspective schematic view of the part of the rear wall of the binding chamber that acts as an upper section of the binding chamber. The upper section is mounted in a pivoting manner on a pair of slides that can be moved by an upper guide.

[0076] Figure 15 is a perspective view of the lower part of the binding chamber that acts as a lower section and comprises holding means for retaining or holding the bale in the upper position when the lifting device resumes the initial lower position of the lifting device. In this Figure 15 , the holding means are provided with four holding members associated with the pivoting arms of the parallelogram mechanism.

[0077] Figure 16 And Figure 17 two schematic views of the plate of the pushing device that inserts the bale into the binding chamber and exerts an active compression force on the bale along the transverse direction "X" of the packages and against the rear wall of the binding chamber. The pushing plate is attached in a hinged manner to the pivoting arms of the parallelogram mechanism, which is suspended on the frame structure of the binding chamber.

[0078] Figure 18 is Figure 16Side view of the pusher plate attached to the pivoting arm of the parallelogram mechanism, showing the plate and arm swinging in an intermediate position.

[0079] Figure 19 is a side view of a plate attached to the pivoting arm of the parallelogram mechanism, the plate being in a rest position intended to free up space in front of the entrance to the strapping chamber to allow bales to pass through.

[0080] Figure 20 is shown in conjunction with Figure 1 Schematic front view of five string binding units in a strapping machine of FIG. In this figure, bales of different nominal lengths "L" are also schematically shown in the strapping chamber.

[0081] Figure 21 yes Figure 1 Schematic rear perspective view of a strapping machine showing the packing of a bale and the ejection operation of the ejection device and the rear wall section, which serves as the lower door of the strapping chamber and on which the packs rest. The ejector device comprises four ejector elements, which are associated with the front and upper walls of the strapping chamber so as to pivot relative to these walls, thereby accompanying the removal of the packs.

[0082] Figure 22 yes Figure 1 Schematic rear perspective view of a strapping machine comprising a changing kit for adjusting the width "a" of the inner space of the strapping chamber to form packages of bales having a layer of bales each formed by two bales having a nominal width "A" of 560 mm.

[0083] Figure 23 Shown is an exploded view of the components of the changing kit to be mounted on the lower part of the strapping chamber. For the sake of clarity, the components of the changing kit are shown in grey. DETAILED DESCRIPTION

[0084] See below Figures 1 to 23 Embodiments of the claimed strapping system and of a strapping machine incorporating the claimed system are described.

[0085] The present invention relates to a baling machine 2 for bales 1, incorporating the claimed baling system, for forming packages 3 of bales 2 of grass or similar material in a baling chamber 4. The baling chamber 4 has the following characteristics: the baling chamber 4 is arranged vertically on a frame 5 of the machine 1, for forming vertical packages 3 of bales 2 along the longitudinal direction "Y" of the packages 3. The baling machine 1 is suitable for bales having a nominal length "L" comprised between 750 mm and 1200 mm or for bales having a nominal length "L" comprised between 600 mm and 1350 mm.

[0086] The bundling chamber 4 of the bale 2 has an inlet 4a of the bale which is arranged in correspondence with a receiving surface 6 which receives the bale 2 from the loading mouth 7. As Figure 1 And Figure 2 It can be seen in the figures that the machine 1 incorporates a conveying device 8 which displaces the bale 2 from the loading mouth 7 to the receiving surface 6 located in front of the inlet 4a. Figure 1 The conveying device 8 of the machine 1 comprises a chain which has traction elements which are traction discs 9, while Figure 2 Another embodiment is shown in which the conveying device 8 comprises a conveyor belt 10 for displacing the bale 2 instead of the traction discs 9. The conveyor belt 10 has the advantage that it does not have mechanical traction elements which are tractioned by a chain. Thus, the bale 2 moves on the conveyor belt 10 quickly and without the risk of the rope or cable 11 breaking, since there are no mechanical traction elements which penetrate the bale 2 during transport. In Figure 1 And Figure 2 In both cases, the element 12 is considered as a pivot which acts as a support to guide the bale 2 between the two conveying portions which are substantially vertical, and to guide the bale 2 towards the receiving surface 6 located in front of the inlet of the bundling chamber 4.

[0087] In order to introduce the bale 2 into the bundling chamber 4, a pushing device is provided which has the following characteristics: it comprises a compression surface 13a which is adapted and dimensioned to exert an active compression force on the bale 2 along the transverse direction "X" of the package 3. In the embodiment shown, the compression surface 13a is provided by a pushing plate 13 which is attached in a hinged manner to a pivot arm 14 of a parallelogram mechanism 15 which is suspended on the receiving surface 6 of the bale 2. The compression surface 13a of the pushing plate 13 is dimensioned to provide a contact surface with the bale 2 which is equal to or greater than 150 cm 2 , for example between 800 cm 2 and 5000 cm 2 , which is adapted to exert an active compression force on the bale 2 which is equal to or greater than 0.05 Kg / cm 2 .

[0088] The pushing plate 13 is actuated by a fluid power cylinder 16 which acts on the parallelogram mechanism 15 so that the pushing plate 13 can be displaced to remain in a substantially vertical position when swinging from a retracted position to a travel position (see Figures 16 to 19 ).

[0089] In the described embodiment, the parallelogram mechanism 15 is mounted so that the pivoting arm 14 is suspended from a structural element 5a of the frame 5 of the strapping machine 1 above the receiving surface 6 for the bales 2, and the parallelogram mechanism 15 is configured so that a side view of the mechanism 15 shows two axes of rotation 17, 18 of the pivoting arm 14, which are arranged so as to be aligned at an acute angle with the horizontal plane. Thus, in the retracted position, the pivoting arm 14 is stowed so that the bales 2 can be positioned in front of the inlet 4a of the strapping chamber 4, while in the advanced position the same pivoting arm 14 penetrates into the strapping chamber 4 to exert an active compression force on the bales 2.

[0090] Within the strapping chamber 4, a lifting platform 19 is provided, which is mounted so as to be vertically displaceable so as to be able to move a layer 20 of two incoming bales 2 to an upper position, in which the retaining means 21 retain the bales 2 so that the lifting platform 19 can be returned to the initial lower position of the lifting platform 19.

[0091] Figures 3 to 7 The images in figure show the sequence of work performed by the system on a layer 20 formed by two bales 2, in which the sum of the nominal widths "A" of the two bales 2 exceeds the reduced width "a" of the strapping chamber 4 (see Figure 3 ). Figure 4 and Figure 5 It is shown that the compression surface 13a of the pusher plate 13 exerts an active compression force on the layer 20 of bales 2 along the transverse direction "X" of the package 3 and against the rear wall 4c of the strapping chamber 4, while the lifting platform 19 vertically displaces the layer 20 to the upper position. In the upper position shown in figure Figure 6 , the front wall 4b and the rear wall 4c of the strapping chamber 4 exert a passive compression force on the bales 2 of the layer 20, since the strapping chamber 4 has a reduced width "a". Figure 7 It is shown that the layer 20 is retained in the upper position by the retaining means 21, while the platform 19 is returned to the lower position of the platform 19, thus waiting for a new layer. The retaining means 21 are hingedly attached to the rear wall 4c of the strapping chamber 4 via a parallelogram mechanism 37.

[0092] Figures 8 to 10 The images of figure show the sequence of work performed by the system on a package 20 formed by seven layers 20 of bales 20 at the end of the loading cycle, when the lifting platform 19 moves to lift the layer 20 of the last bales. Figure 9 It is shown that the lifting platform 19 exerts an active compression force on the bales 2 along the longitudinal direction "Y" of the package 3 to vertically compress the package 3. Figure 9One complete turn of the rope 23 is also shown, which surrounds the packages 3 of the bundle 2, and the respective needle 22 of the rope 23, which holds the rope 23. An element 24 is also shown, which acts as a pivot to direct the turns of the rope 23 from the outside of the bundling chamber 4 according to an upward trajectory "T" inclined with respect to the surface of the packages 3. In Figure 10 In the middle, the needle that holds the respective rope 23 has been displaced to a higher position to form the bundle that binds the packages 3. The upwardly inclined trajectory "T" of each of the turns of the rope 23 facilitates tensioning the rope 23 so that it clings to the packages 3, while reducing the length of rope 23 required to perform the binding operation.

[0093] According to one embodiment, the machine 1 claimed comprises a plurality of binding units 25 distributed in correspondence with the inlet 4a of the bundles 2 of the bundling chamber 4. Each of these binding units 25 provides one of the turns of the rope 23 that coils on the packages 2 of the bundle. In the preferred embodiment, four of the binding units 25 are distributed in such a way as to be aligned to bind the packages 3 formed by the bundles 2 of nominal length "L" comprised between 800 mm and 900 mm using four turns of the rope 23, while a fifth binding unit 25 is distributed in alignment with the other four but in an outer lateral position, displaced in such a way as to be able to bind the packages 3 formed by the bundles 2 of nominal length "L" equal to or greater than 1000 mm, for example bundles 2 of length "L" comprised between 1100 mm and 1200 mm, using five turns of the rope 23.

[0094] The prior art system does not comprise a fifth binding unit, since experience has shown that this would lead to a greater risk of turning over the layers 20 of the bundle 2 as a result of the action of the layers 20 in contact with the rope 23 when they are introduced into the bundling chamber 4. In the claimed system, unlike the prior art system, the compression surface 13a of the pushing device 13 keeps the bundle 2 inside the bundling chamber, thus preventing the turning over of the layers 20, while the lifting platform 19 moves the layers 20 vertically. The claimed bundling system can therefore comprise more than four binding units 25, for example five binding units 25, six binding units 25 or even seven binding units 25, so that it is optimal for processing bundles of nominal length "L" comprised between 750 mm and 1200 mm.

[0095] According to a preferred embodiment, the claimed system comprises an adjustment mechanism for adjusting the width "a" of the bundling chamber 4 as a function of the nominal width "A" of the bales 2 forming each layer 20. Thereby, the system is adapted to be used with bales 2 of different nominal width "A", for example the system is adapted to be used with bales 2 having a nominal width "A" of 440 mm, 460 mm or 490 mm. Therefore, as a function of the nominal width "A" of the bales 2, the user can adjust the width "a" of the bundling chamber 4 so that the front wall 4a and the rear wall 4c of the bundling chamber 4 itself exert a passive compression force on the layers 20 of bales 2 in the transversal direction of the packages 3.

[0096] For example, the width "a" of the bundling chamber 4 can be designed to have a value of 880 mm, which is lower than the value of 920 mm resulting from the sum of the nominal width "A" of two bales 2 of 460 mm. In this way, the claimed system makes it possible to obtain a package 3 which is very compact both in the transversal direction and in the longitudinal direction of the package, since the passive compression force exerted by the front wall 4b and by the rear wall 4c of the bundling chamber 4 limits the lateral expansion of the layers 20 of bales 3 at the end of the loading cycle, when the lifting platform 19 presses the layers 20 in the longitudinal direction. Therefore, the breaking of the ropes of the bales, which often occurs in the systems of the prior art, is also avoided.

[0097] In the embodiment shown in the attached figures, the rear wall 4c of the bundling chamber 4 comprises a wall portion 4c which acts as a lower unloading door 26 of the package 3 and a wall portion 4c which acts as an upper unloading door 27 of the package 3. In order to increase or decrease the width "a" of the internal space of the bundling chamber 4, both the unloading doors 26, 27 are mounted in a pivoting manner on respective slides 28, 29 which, in turn, are mounted in a displaceable manner on respective guides 30 and 31 on which the doors 26 and 27 move horizontally (see Figures 12 to 14 ).

[0098] Figure 11 and Figure 12 is Figure 1 a side view of the bundling machine 1 showing the bundling chamber 4 adjusted to two different working widths "a". Figure 12 shows the bundling chamber with a greater working width "a" when the lower unloading door 26 and the upper unloading door 27 of the rear wall 4c have been displaced horizontally outwards on the slides 28 and 29 and on the respective guides 30 and 31 of the slides 28 and 29.

[0099] To ensure the closed position of both the unloading doors 26, 27 and to prevent the opening of these doors 26, 27 when the compression surface 13a exerts the active compression force on the layers 20 of the bale 2, the claimed system comprises fixing means which act by preventing the opening of both the unloading doors 26, 27.

[0100] In the embodiment described and illustrated in the attached drawings, the fixing means comprise at least one nail-like fastening member 32, a force multiplier mechanism 33 associated with said fastening member 32 and a fluid power element 34, such as a hydraulic cylinder, for actuating the multiplier mechanism 33. Figure 11 and Figure 12 The fixing means are shown mounted on the side wall 4d of the baling chamber 4, with the fastening member 32 in the closed and locked position, the doors 26, 27 of which the holding support 35 is attached in an integral manner to the rear wall 4c of the baling chamber. The fluid power element 34 has the feature that it is mounted in a displaceable manner on the side wall of the baling chamber 4 by means of a threaded rod mechanism 36, which allows the position of the fixing means to be adapted to the width "a" of the baling chamber 4 (see Figure 12 ).

[0101] Figure 15 A perspective view of the rear wall portion 4c of the baling chamber 4 is shown, which serves as a lower unloading door 26 and comprises holding means 21 for holding the layers 20 in an upper position when the lifting platform 19 restores its initial lower position. As can be seen in this Figure 15 and Figure 13 , the holding means 21 comprise four holding members 21a associated with parallelogram mechanisms 37 mounted on the wall portion 4c, which itself serves as a lower door 26 of the baling chamber 4. Thanks to these features, when the plurality of parallelogram mechanisms 37 is actuated, the holding members 21a move linearly so that they are in uniform contact with the bale 2, thus ensuring effective holding without damaging the layers 20 of the bale 2 (see Figure 7 ). In the retracted position, the holding members 21a are hidden between the bars that make up the lower unloading door structure 26 (see for example Figure 3 ).

[0102] Figure 21 is Figure 1a rear perspective view of the bundling machine 1 showing the packaging 3 of the bale 2 and the pusher device 38 being pushed out, the pusher device 38 comprising four pusher members 38a of the packaging 3. In this figure, it can be seen that the lower unloading door 26 and the upper unloading door 27 are open when the fastening members 32 of the doors 26, 27 release the holding supports 35 to allow the unloading doors 26, 27, actuated by the two hydraulic cylinders 39, 40, to pivot on the respective support slides 28, 29. The pusher members 38a are associated with the front wall 4b and the upper wall 4e of the bundling chamber 4 so that, as the machine 1, drawn by a tractor (not shown), advances through the field, the pusher members 38a pivot with respect to these walls 4b, 4e to accompany the removal of the packaging 3.

[0103] Figure 22 and Figure 23 The components of the change kit, shown in grey, are used to adjust the width "a" of the internal space of the bundling chamber 4 to form a packaging of bales having a nominal width "A" equal to or greater than 500 mm, for example a packaging of bales having a nominal width "A" of 560 mm. Alternatively, the change kit allows to adjust the width "a" of the internal space of the bundling chamber to form a packaging with layers of bales, each layer of bales being formed by three or four bales having a nominal width "A" equal to or less than 500 mm, for example each layer of bales being formed by three bales each having a nominal width "A" of 460 mm.

[0104] For the embodiment shown in Figure 22 and Figure 23 The change kit comprises, for the embodiment shown, a bale lifting platform extension 19' which can be attached in a removable manner to the already existing bale lifting platform 19, a first pair of slide extension 28' which can be attached in a removable manner to the already existing at least one pair of slides 28 mounted displaceable on a pair of lower guides 30, and a second pair of slide extension 29' which can be attached in a removable manner to the already existing at least one pair of slides 29 mounted displaceable on a pair of upper guides 31.

[0105] As can be seen in Figure 22 For this particular embodiment, the rear wall portion 4c which acts as lower unloading door 26 is mounted to pivot clockwise on said first pair of slide extension 28', and the rear wall portion 4c which acts as upper unloading door 27 is mounted to pivot counterclockwise on said second pair of slide extension 29'.

[0106] Next, reference is made toFigures 1 to 21 The operation of the claimed bundling system is described. In particular, a method for forming a baled package 3 of bales 2 of forage or similar material on a frame 5 of the claimed bundling machine 1 is described, wherein the bales 2 of the baled package 3 are arranged vertically on the frame 5 along a longitudinal direction (“Y”) of the bales 3.

[0107] First, the bales 2 are moved continuously from the loading mouth 7 to a receiving surface 6 of the bales 2 located in front of an inlet 4a of the bundling chamber 4 by means of a conveying device 8 (see Figure 1 and Figure 2 ) of the bales 2.

[0108] The two bales 2 forming the first layer 20 of bales 2 are introduced continuously into the bundling chamber 4 by means of a pushing device which is in contact with the bales 2 and moves the bales 2 horizontally one after the other on the receiving surface 6 of the bales 2. When the layer 20 is loaded, the compression surface 13a of the pushing plate 13 exerts an active compression force on the layer 20 along a transverse direction “X” of the bales 3 and against the rear wall 4c of the bundling chamber 4, while the lifting platform 19 moves the layer 20 vertically within the bundling chamber 4 to an upper position (see Figure 4 and Figure 5 ).

[0109] According to a preferred embodiment, wherein the width “a” of the bundling chamber 4 is less than the value obtained by the sum of the nominal widths “A” of the two bales 2 of the layer 20, when the layer 20 has been moved to the upper position (see Figure 6 ), the front wall 4b and the rear wall 4c of the bundling chamber 4 exert a passive compression force on the plant material of the layer 20. Then, the retaining means 21 are actuated to retain the layer 20 in the upper position and allow the lifting platform 19 to return to the initial position of the lifting platform 19, waiting for a new layer 20 (see Figure 7 ).

[0110] The previous working sequence is repeated continuously to load a certain number of layers 20 of bales 2 until reaching the end of the loading cycle (see Figure 8 ). At this point, the lifting platform 19 travels vertically again within the bundling chamber 4 to exert an active compression force on the layers 20 of bales 2 along the longitudinal direction “Y” of the bales 3, so that the plant material of the bales 3 is compressed vertically (see Figure 9 ).

[0111] According to the preferred embodiment described above, in which the bundling chamber 4 has a reduced width "a", the passive compression exerted by the front wall 4b and the rear wall 4c of the bundling chamber 4 limits the lateral expansion of the layer 20 when the lifting platform 19 compresses the package 3 in the vertical direction. Thus, the breaking of the twines of the bale 2 is avoided and it is easier to obtain a very compact bale of packages 3, according to the nominal length "L" of the bale 2, using four or more turns of twine 23, for example using five turns of twine 23 or six turns of twine 23 to bind the packages 3 of the bale 2 by means of the twine 23.

[0112] To unload the packages 3, first the fastening members 32 are released, which fasten the retaining supports 35 of the lower section 26 and the upper section 27 of the bundling chamber 4. Next, the fluid power cylinders 39 of the upper section 27, the fluid power cylinders 41 that actuate the ejector devices 38 and finally the fluid power cylinders 40 of the lower section 26 are actuated (see Figure 21 ).

[0113] The system and method claimed have the characteristic that, before starting the loading and forming process of the packages 3, the user can judge whether to modify the width "a" of the internal space of the bundling chamber 4 according to the nominal width "A" of the bale 2 to be processed or even according to the humidity of the plant material in the bale 2, since the humidity modifies the nominal dimensions of the bale 2. In any case, thanks to the system claimed, the width "a" of the internal space of the bundling chamber 4 can be modified with an adjustment value that can even be lower than the value obtained by the sum of the nominal width "A" of the bale of the layer 20 formed, without there being a risk that the greater actual width of the bale 2 prevents the layer 20 of the bale 2 from being introduced into the internal space of the chamber 4.

[0114] Although reference has been made to a specific embodiment of the application, it is apparent for the person skilled in the art that the described system, machine 1 and method can be subject to a plurality of changes and modifications, and that all the details mentioned can be replaced with other details that are technically equivalent, without departing from the scope of protection defined by the attached claims. For example, although a machine 1 has been described provided with a bundling chamber 4 suitable for forming layers 20 of two bale packages 2, similar results can also be obtained with a machine 1 such that the bundling chamber can form layers comprising more than two bale packages. Similarly, although a pusher plate 13 has been described that is attached in an articulated manner to two pivoting arms 14 of a parallelogram mechanism 19, another pusher plate or compression surface associated with another type of actuation mechanism can also be used, provided that the plate or compression surface can also exert an active compression force on the layer of bale packages 3 in the transverse direction "X" of the packages 3 while the lifting platform moves the layer to the upper position. Similarly, although a machine 1 has been described provided with five binding units 25, similar results can also be obtained with a machine comprising six, seven or up to eight binding units of packages 3.

Claims

1. A bale tying system for forming a package (3) of bales (2) of grass or similar material, the package (3) comprising a plurality of layers (20) of bales (2), the bales (2) having a predetermined nominal width ("A"), the tying system comprising: - a frame (5) which can be attached to a tractor and can be pulled by said tractor, a receiving surface (6) for the bale (2), said receiving surface (6) for the bale (2) being situated on said frame (5), a bundling chamber (4) for the bales (2), said bundling chamber (4) being arranged on said frame (5) so as to form a package (3) of bales (2) arranged vertically in the longitudinal direction (Y) of said package (3), said bundling chamber (4) comprising an inlet (4a) for the bales (2) arranged in correspondence with a receiving surface (6) of said bales (2), - a pushing device arranged to introduce a bale (2) into the bale chamber (4) through an inlet (4a) for the bale (2) of the bale chamber (4), - a vertically displaceable bale lifting platform (19) mounted to displace a bale (2) from a lower position to an upper position within the strapping chamber (4), and - holding means (21) for holding the bale (2) in the upper position when the bale lifting platform (19) returns to its initial lower position, It is characterized by: - the pushing means comprise a compression surface (13a) suitable for exerting an active compression force on the layers (20) of the bale (2) according to the transverse direction (X) of the package (3) inside the strapping chamber (4), - wherein the strapping system comprises processing and control means configured to send a compaction signal to an actuation means associated with the compression surface (13a) so that: the compression surface (13a) applies the active compression force to the layer (20) of the bale (2) while the bale lifting platform displaces the layer (20) vertically in the interior space of the strapping chamber (4).

2. The strapping system according to claim 1, wherein: The processing and control device is configured to send a compression signal to the bale lifting platform (19) so as to cause the bale lifting platform (19) to apply an active compression force to the bale (2) in the longitudinal direction (Y) of the package (3) at the end of a loading cycle (20) of the bale (2) in the package (3).

3. The strapping system according to claim 1 or 2, wherein: The internal space of the strapping chamber (4) comprises a width ("a") in the transverse direction (X) of the packages (3), said width ("a") being equal to or less than the value obtained by the sum of the nominal widths ("A") of the bales (2) forming the layer (20).

4. The strapping system according to claim 1 or 2, wherein: The compression surface (13a) for the bale (2) is dimensioned to provide an area of ​​contact with the bale (2) equal to or greater than 150 cm 2 contact surface.

5. The strapping system according to claim 1 or 2, wherein: The compression surface (13a) of the bale (2) is dimensioned to provide a pressure suitable for providing a layer (20) of the bale (2) with a pressure equal to or greater than 0.05 kg / cm 2 Active compressive force on the contact surface.

6. The strapping system according to claim 1 or 2, wherein: The compression surface (13a) comprises a push plate (13), and the actuation means of the push plate (13) comprises a parallelogram mechanism (15).

7. The strapping system according to claim 6, wherein: The push plate (13) is attached to the pivot arm (14) of the parallelogram mechanism (15) in an articulated manner, and the parallelogram mechanism is mounted so that the pivot arm (14) and the push plate (13) are suspended above the bale receiving surface (6), the articulation of the parallelogram mechanism being configured so that the push plate (13) can swing on the bale receiving surface (6) and maintain contact with the bale (2) to horizontally displace the bale (2) and exert the active compressive force in the transverse direction (X) within the strapping chamber (4).

8. The strapping system according to claim 7, wherein: The ends of the pivot arm (14) are attached to and rotatably hinged to two rotation axes (17, 18), which are arranged so that the pivot arm (14) can be stowed in a retracted position so that the bale (2) can be positioned in front of the entrance (4a) of the strapping chamber (4).

9. The strapping system according to claim 1 or 2, wherein: The strapping chamber (4) comprises a rear wall (4c), at least a portion of which defines a door for unloading packages (3), the strapping system comprising a fixing device for preventing the door from opening when the compression surface (13a) applies the active compression force to the bale (2).

10. The strapping system according to claim 9, wherein: The fixing device for preventing the unloading door from opening comprises: - at least one fastening member (32) of the unloading door, - a force multiplier mechanism (33) associated with said fastening member (32), and - at least one fluid dynamic element (34) or electromechanical device arranged to actuate said force multiplier mechanism (33).

11. The strapping system according to claim 3, comprising an adjustment mechanism for modifying the width ("a") of the interior space of the strapping chamber (4) based on the nominal width ("A") of the bales in the layer (20).

12. The strapping system according to claim 11, wherein: The adjustment mechanism comprises a rear wall (4c) of the strapping chamber (4), at least a portion of which defines an unloading door for the packages (3), the rear wall (4c) being displaceably mounted on at least one pair of guides so as to be able to adjust the width ("a") of the inner space of the strapping chamber (4) according to the nominal width ("A") of the bales (2) in the layer (20).

13. The strapping system according to claim 12, wherein: The rear wall (4c) of the strapping chamber (4) includes a first rear wall portion and a second rear wall portion, the first rear wall portion serving as the unloading door, and the unloading door is a lower unloading door (26), wherein the first rear wall portion serving as the lower unloading door (26) is mounted to pivot clockwise on at least one pair of slides (28) mounted on a pair of lower guides (30) in a displaceable manner, and the second rear wall portion serving as the upper door (27) is mounted to pivot counterclockwise on at least one pair of slides (29) mounted on a pair of upper guides (31) in a displaceable manner.

14. The strapping system according to claim 1 or 2, wherein: The holding device comprises a bale holding device (21) for holding a bale, the bale holding device (21) being hingedly attached to a rear wall (4c) of the strapping chamber (4), at least a portion of the rear wall (4c) of the strapping chamber defining an unloading door for the packages (3), the bale holding device (21) comprising at least one holding member (21a) for holding the bale (2) in the upper position, the holding member (21a) being associated with a parallelogram mechanism (37), the holding member (21a) being linearly displaceable in the transverse direction (X) of the package (3) when the parallelogram mechanism (37) is actuated to hold the bale (3) in the upper position within the strapping chamber (4).

15. The strapping system according to claim 1 or 2, comprising a plurality of strapping units distributed so as to be aligned in correspondence with the inlet (4a) of the strapping chamber (4) for the bales, each of the strapping units being capable of providing a looped string (23) on the package (3), the strapping system comprising an element (24) serving as a pivot member for guiding the looped string (23) from the outside of the strapping chamber (4) according to an upward trajectory ("T") inclined relative to the surface of the package (3).

16. The strapping system according to claim 1 or 2, comprising: at least four strapping units distributed so as to be aligned in correspondence with the bale inlet (4a) of the strapping chamber (4) so ​​as to be able to strap a package (3) formed of bales having a nominal length ("L") equal to or greater than 750 mm with four turns of string; and a fifth strapping unit distributed in alignment with the other four strapping units to be able to strap a package (3) formed of bales having a nominal length ("L") equal to or greater than 1000 mm with at least five turns of string.

17. The strapping system according to claim 1 or 2, comprising an ejector device (38) for bundles (2) and packages (3) of bundles (2), the ejector device (38) being provided with a plurality of ejector members (38a), each of the ejector members (38a) comprising a first member portion associated with the front wall (4b) of the strapping chamber and a second member portion associated with the upper wall (4e) of the strapping chamber, wherein The second member portion is hingedly attached to the upper wall (4e) of the strapping chamber (4), and the ejector member (38a) is pivotable relative to the front wall (4b) and the upper wall (4e) of the strapping chamber (4) to facilitate removal of the package (3) when the ejector device (38) is actuated.

18. A baling machine (1) for forming packages (3) of bales (2) of grass or similar material, the bales (2) having a nominal length ("L") comprised between 750 mm and 1200 mm, or the bales (2) having a nominal length ("L") comprised between 600 mm and 1350 mm, wherein The strapping machine (1) comprises a strapping system according to any one of claims 1 to 17.

19. The strapping machine (1) according to claim 18, comprising a changing kit for adjusting the width ("a") of the inner space of the strapping chamber (4).

20. The strapping machine (1) according to claim 19, comprising a strapping system according to claim 13, wherein The modification kit includes: - a bale lifting platform extension (19') which is removably attached to the existing bale lifting platform (19), - a first pair of slide extensions (28') removably attachable to at least one existing pair of slides (28) displaceably mounted on the pair of lower guides (30), wherein the first rear wall portion serving as a lower unloading door (26) is mounted to pivot clockwise on the first pair of slide extensions (28'), and - a second pair of slide extensions (29') which are removably attachable to at least one existing pair of slides (29) mounted displaceably on a pair of upper guides (31), wherein the second rear wall portion serving as the upper door (27) is mounted to pivot counterclockwise on the second pair of slide extensions (29').

21. A method for forming tied packages (3) of bales (2) of grass or similar material, the bales (2) being arranged vertically in the longitudinal direction of the packages (3) on the frame (5) of a baling machine (1) according to any one of claims 18 to 20 for tying bales (2), wherein: The package (3) comprises a plurality of layers (20) of bales, and wherein the method comprises the steps of: a) introducing a layer (20) of bales (2) into a bale bundling chamber (4), said bundling chamber (4) comprising a rear wall (4c), at least a portion of said rear wall (4c) of said bundling chamber defining an unloading door for packages (3), b) applying an active compressive force to the layer (20) of the bale (2) in the transverse direction (X) of the package by means of a pushing device, the pushing device comprising a compression surface (13a) suitable for applying the active compressive force to the layer (20) of the bale (2) and against the rear wall (4c) of the strapping chamber (4), and c) When performing step b), the layer (20) of bales (2) is vertically displaced to an upper position by means of a vertically displaceable bale lifting platform (19), which is installed in the strapping chamber (4).

22. The method according to claim 21, comprising the steps of: d) at the end of a bale loading cycle, displacing the bale lifting platform (19) vertically within the strapping chamber (4) to apply an active compressive force to the layers (20) of the bale (2) in the longitudinal direction (Y) of the package (3).

Images