The invention relates to a device for wrapping a film round mowed material which has been pressed into a bale, comprising a mobile frame, supply means arranged on the frame for supplying the bale, wrapping means arranged on the frame and connecting to the supply means for wrapping the film round the supplied bale, and discharge means arranged on the frame and connecting to the wrapping means for discharging the wrapped bale. Such a wrapping device is known and is marketed by applicant in different variants under the name "Tawi (mini) bale wrapper".

The known wrapping device comprises a mobile frame intended to be drawn by a tractor. Situated on the front side of the frame are a pick-up and a short conveyor with which compressed bales of mowed material can be picked up from the land. The conveyor feeds the bales to the actual wrapper, which is formed by at least one horizontal wrapping table on which the bale comes to rest, and a wrapping arm which carries a roll of film at both ends and which is rotatable around the wrapping table on a vertical shaft. The wrapping table is provided with a movable surface, whereby a bale at a time is tilted round a horizontal axis while the wrapping arm rotates around it and unwinds the film. The bale is thus wrapped in film on all sides. Once the bale has been sufficiently wrapped it is placed back on the ground, optionally via a gathering system.

In the mini-bale wrapper a second wrapping table, which holds the bale in place during the wrapping, is arranged some distance above the wrapping table. This is necessary because small bales, which are for instance used as feed in hobby livestock farming, usually weigh only several tens of kilos and could be thrown off by the force of the pre-tensioned film. In the case of bales for

professional use, which weigh several hundred kilos, this problem does not occur.

The known wrapping device has the drawback that it is relatively large and cannot therefore be readily combined with a mobile baler. In practice therefore the baler and the wrapper are driven over the land one behind the other by two separate tractors. This requires many people and a lot of equipment, and is thus relatively expensive. The capacity of the known wrapping device is moreover relatively limited as a result of the large number of rotations of the wrapping arm and the wrapping table necessary to fully wrap a bale. Particularly for small bales, which can be pressed

relatively quickly, the wrapping device is the limiting factor in respect of increasing productivity.

A mobile wrapping device for small rectangular bales is also described in American patent 5,799,466. In this known device the small bales are first assembled into a larger rectangular package of nine bales, around which film is then wrapped. The wrapping device is provided with two vertical discs which are rotatable about a horizontal axis perpendicularly of the direction of travel and which can be moved toward each other in order to clamp the bale package. The wrapping discs can be moved up and downward in order to create space for their rotation movement, whereby film from a fixed roll is wrapped around the bale package. In

addition, the wrapper is pivotable about a horizontal axis parallel to the rotation axis, in order to set the bale package down on the ground after wrapping. The wrapping device further has a rotational table for the purpose of rotating the bale package a quarter-turn in a first direction after wrapping, and then wrapping it further in a second direction.

The wrapping device according to US 5,799,466 is exceptionally complex structurally, and thereby relatively heavy and costly. This device is moreover not suitable for wrapping individual small bales.

The invention now has for its object to provide a wrapping device of the above described type, wherein the stated drawbacks do not occur, or at least to lesser extent. According to a first aspect of the invention this is achieved in such a wrapping device in that the wrapping means comprise at least one pair of substantially vertically oriented wrapping-clamping members which are placed at a mutual distance in horizontal direction and between which the bale is clamped during wrapping, and at least one film dispensing unit which is movable along a closed path in a substantially vertical plane and which carries at least one roll of film. By using vertically oriented wrapping-clamping members a compact construction can be realized which is highly suitable for combination with a baler. Owing to this compact form it is moreover possible to combine a plurality of sets of wrapping means in a single machine, whereby the wrapping capacity can be increased.

The film dispensing unit can comprise a wrapping arm which is rotatable about a lying axis and on which at least one film carrier is mounted. Use can thus be made of a tried and tested technique.

It is on the other hand also possible for the film dispensing unit to comprise an endless transport element which is movable along a guide and on which at least one film carrier is mounted. Such a fixed guide can take a more robust form than a rotatable arm. It is recommended in that case that the guide has a flattened form at least on its underside. The overall construction height of the wrapping device can thus remain limited and bales do not have to be carried upward for the purpose of wrapping, this being an advantage particularly in the case of large and heavy bales.

The wrapping-clamping members are preferably formed by wrapping tables which each have a movable surface for rotating the bale clamped therebetween. The bale can thus be wrapped on all sides with film.

In another embodiment, which is particularly suitable for wrapping relatively large and heavy bales, the wrapping-clamping members each comprise at least one pivotally mounted pair of rollers. Because the corners of the bale can be supported between the rollers during wrapping, it is possible to suffice with a smaller clamping force .

In order to enable easy loading of the wrapping device it is then recommended that each pair of rollers is pivotable between an operative position for rotating the bale clamped therebetween and a loading and unloading position for receiving and discharging the bale.

When the wrapping means are arranged relatively high on the frame and the supply means comprise an elevator conveyor, space is left clear lower in the frame for other functions so that a compact structure is obtained. Owing to the high position of the wrapping means the wrapping process can moreover be easily monitored from a tractor coupled in front of the wrapping device.

The supply means preferably comprise upstream of the elevator conveyor a first, lower supply segment and

downstream of the elevator conveyor a second, upper supply segment, wherein the first and second supply segments are oriented in opposite directions. By in effect feeding the bales back using the second, upper supply segment the wrapping means can be arranged relatively far forward in the frame, whereby the wrapping device as a whole can be

relatively short.

A simple and reliable supply of the bales is ensured when the elevator conveyor extends to a position above the second, upper supply segment, which comprises a slide track.

In order to move the bales upward in reliable and simple manner the elevator conveyor preferably comprises an elevator belt with hooks.

In order to prevent the wrapped bales falling roughly onto the ground, which could damage the film, the discharge means are preferably adapted to lower the wrapped bale onto the ground surface.

This can be realized in simple manner when the discharge means comprise a substantially vertically

displaceable receiving member.

A structurally simple embodiment is obtained when the receiving member comprises an arm connected pivotally to the frame and a table carried thereby.

In order to enable simple unloading of the bales it is recommended that the receiving member comprises a roller track.

When the receiving member also forms part of the supply means different functions are combined in one component, thereby simplifying the structure. This

embodiment is particularly suitable for processing large bales for professional use.

The wrapping-clamping members are preferably movable between an operative position, in which their mutual distance is relatively small, and a loading and unloading position in which they are relatively further removed from each other, and the receiving member is preferably adapted to support the bale when the wrapping-clamping members occupy their loading and unloading position. The bales can thus be clamped between the wrapping-clamping members during the wrapping, and can be taken over by the receiving member after wrapping.

The receiving member can then preferably be moved synchronously with the wrapping-clamping members between a retracted and an extended position so that the receiving member can be placed between the wrapping-clamping members to pass on the bales during loading or receive them again during unloading.

In order to increase the capacity of the wrapping device and bring it to some extent into line with that of a baler, according to a second aspect of the invention it is provided with two sets of wrapping means placed on either side of the supply means. A well-balanced construction is moreover obtained hereby.

In this case the wrapping device is preferably further provided with a distributing member which co-acts with the supply means and which is adapted to guide supplied bales alternately to the first or second set of wrapping means. The distributing member can here be alternately movable in one of two opposite directions and can for instance comprise a conveyor belt drivable in two opposite directions or a slide movable in two opposite directions.

The invention also relates to a combination of a mobile device for pressing mowed material into bales and a wrapping device as described above.

When the baler device and the wrapping device are attached to each other they can be drawn by a single tractor. It is hereby possible to suffice with fewer tractors and fewer personnel. A structurally simple solution is obtained when the baler device and the wrapping device are constructed as a whole and comprise a shared mobile frame.

The baler device can here have a delivery opening for the pressed bales, to which the supply means of the wrapping device can connect .

Preferably situated between the delivery opening of the baler device and the wrapping means is a release member, whereby bales which do not need to be wrapped in film can as it were bypass the wrapping device.

The invention is now elucidated on the basis of three embodiments, wherein reference is made to the

accompanying drawing, in which:

Fig. 1 is a perspective side view of a first embodiment of the wrapping device according to the .invention in combination with a small baler on a shared mobile frame, wherein a set of wrapping means is omitted for the sake of clarity,

Fig. 2 is a perspective rear view of the wrapping device and baler of fig. 1,

Fig. 3 is a perspective front view of two pairs of wrapping-clamping members and, placed therebetween, a conveyor with distributing member of the wrapping device of fig. 1 and 2,

Fig. 4 is a schematic side view along arrow IV in fig. 1, which shows the transfer of a bale from a lower supply segment to an elevator conveyor,

Fig. 5 is a schematic side view along arrow V in fig. 1, showing the bale on an upper supply segment,

Fig. 6 is a side view of an alternative embodiment of the wrapping device in combination with a press for large bales, Fig. 7 is a schematic rear view of the wrapping device as according to arrow VII in fig. 6,

Fig. 8 is a schematic rear view of yet another embodiment of the wrapping device, which is particularly suitable for wrapping large bales, during loading thereof,

Fig. 9 is a view corresponding to fig. 8 of the wrapping device during operation, and

Fig. 10 is a schematic side view of the wrapping device as according to arrow X in fig. 8 and 9.

A device 1 according to the invention for wrapping a film 2 round pressed bales of mowed material 3 comprises a frame 4 with a chassis 5. Supply means 6 for supplying bales 3 are arranged on frame 4. In the shown embodiment supply means 6 comprise a first, lower supply segment 7, an elevator conveyor 8 connecting thereto and a second, upper supply segment 9 connecting to elevator conveyor 8. The first and second supply segments 7, 9 operate in mutually opposite directions so that during supply the bales 3 run through a substantially C-shaped path.

The lower supply segment 7 is here passive and is embodied as a slide track, over which bales 3 slide when they are pushed out of a baler 23 to be discussed below. On the front side this first segment 7 is connected to frame 4 for pivoting about a shaft 31, while its rear side is connected releasably to elevator conveyor 8. This first supply segment 7 can thus also function as release member, whereby pressed bales 3 can be set down directly on the ground G when it is not wished that they be wrapped in film 2.

Elevator conveyor 8 here comprises an endless elevating chain 27 with hooks 32 which is received in an upright sub-frame 33. Elevator conveyor 8 is bounded on the front side by a closing plate 34 which is pivotable about a shaft 35 on the top side. Elevator conveyor 8, which

comprises a set of deflecting plates 36 on the top, extends to a position above the upper supply segment 9.

This upper supply segment 9 comprises a slide track 37 and a transport chain 39 connecting thereto and driven by a motor 38. This transport chain 39 is provided over half its periphery with hooks 40, with which a supplied bale 3 can be pulled onto a distributing member 29 to be discussed below. When bale 3 rests on distributor member 21, hooks 40 are situated on the underside so that bale 3 lies free.

Wrapping means 10 are further arranged on frame 4 for wrapping film 2 around the supplied bales 3. These wrapping means 10 connect to supply means 6. According to the invention wrapping means 10 comprise one or more pairs of vertically oriented wrapping-clamping members 11 placed at a distance from each other in horizontal direction. These wrapping-clamping members 11 are connected resiliently to each other and fixedly clamp each bale 3 during wrapping so that it cannot fall. A wrapping arm 12, which carries on both ends a roll of film 13 and a set of tensioning and guide rollers 41, is mounted in frame 4 for rotation about a lying shaft 14.

The wrapping-clamping members 11 take the form here of wrapping tables, each having a movable surface which in the shown embodiment is formed by a bar conveyor 15. Bar conveyor 15 comprises a large number of bars 46 mounted between two yielding chains or belts 47. The bar conveyors 15 of each pair of wrapping tables 11 are also rotatable in the same direction, for instance both clockwise or counter- clockwise. The mutually facing surfaces of wrapping tables 11 thereby move in opposite directions so that the bale 3 clamped therebetween is rotated (fig. 7) . Wrapping tables 11 here move resiliently away from and toward each other, while bar conveyors 15 also yield to some extent so that the rectangular bale 3 remains firmly clamped between the vertical wrapping tables 11 during all phases of its rotating movement. Owing to the rotating movement about a horizontal axis A running in longitudinal direction in combination with the rotation of wrapping arm 12 about shaft 14, each bale 3 is wrapped in the film on all sides. The wrapping movement is directed here in the longitudinal direction of the rectangular bales 3.

Other types of movable surface could otherwise also be used instead of bar conveyors 15. It is for instance possible to envisage a type of caterpillar track, such as the plastic caterpillar tracks used under small excavators.

Discharge means are further arranged on frame 4 to discharge the wrapped bales 3. These discharge means, which connect to wrapping means 11, are formed in the shown embodiment by a vertically displaceable receiving member 16. This receiving member 16 here comprises a pair of arms 17 which are each pivotable about a horizontal shaft 18 and which support a table 19. These arms 17 form a

parallelogram. Table 19 is connected to parallelogram arms 17 for pivoting about a shaft 20 so that this table can be kept horizontal when receiving and lowering bales 3, and pivots only when very close to the ground G to a position in which bales 3 can slide therefrom. Thus prevented is that bales 3 fall onto the ground G from too great a height and film 2 is damaged. In order to enhance sliding of bales 3, table 19 is here embodied as a roller track. Table 19 is constructed for this purpose from two flanges 28 between which a series of shafts 29 is arranged. Rollers 30 are arranged for free rotation on shafts 29. As indicated in fig. 2 in broken lines, receiving member 16 is displaceable between a higher position, in which table 19 is situated between wrapping tables 11, and a lower position in which the free outer end of table 19" is situated at the level of ground G.

In order to increase the wrapping capacity, wrapping device 1 is provided according to another aspect of the invention with two sets of wrapping means 10 placed on either side of supply means 6. Because the capacity of a baler is in practice roughly double that of a wrapping device 1, particularly when relatively small bales 3 are being pressed, the wrapping capacity is thus brought better into line with the pressing capacity. Moreover ensured in this way is that the structure of wrapping device 1 is balanced. A distributing member 21 movable in two opposite directions is present to cause the supplied bales 3 to be wrapped alternately by the left or right-hand set of wrapping means 10. In the shown embodiment this member is formed by a conveyor belt 42 which simultaneously forms part of the upper supply segment 9. Conveyor belt 42 consists of two sets of rollers 43, 44 which are driven counter- clockwise or clockwise as desired via a shared chain or belt 45. Bales 3 thus fall alternately between the left or right- hand pair of wrapping tables 11. Bar conveyor 15, which connects to conveyor belt 42, is otherwise also driven during the operation of distributing member 21 so that bales 3 are as it were pulled into the space between wrapping tables 11.

Wrapping tables 11 are otherwise movable between an operative position, in which their mutual distance is relatively small, and a loading and unloading position in which they are relatively further removed from each other.

Table 19 of receiving member 16 is adapted to support bale 3 when wrapping tables 11 occupy their loading and unloading position. For optimal support of bale 3 the width of table 19 is roughly equal to the mutual distance between wrapping tables 11. When wrapping tables 11 are moved toward each other, the width of table 19 must then also decrease. For this purpose table 19 can be moved synchronously with wrapping tables 11 between an extended position, when wrapping tables 11 occupy their loading and unloading position, and a retracted position, when wrapping tables 11 are in their operative position. In the shown embodiment this is achieved in that shafts 29 take a divided form.

Once wrapping tables 11 have been moved back to their operative position, in which they clamp bale 3, table 19 can be moved downward by pivoting the arms 17 of

receiving member 16 downward. Receiving member 16 hereby does not come into conflict with wrapping arm 12 when it begins to rotate in order to wrap bale 3 in film 2.

It is otherwise possible to envisage not moving wrapping tables 11 apart during loading but holding them in their operative position and causing their bar conveyors 15 to rotate in opposite direction. The mutually facing parts of conveyors 15 then move in the same direction, whereby bale 3 can be pulled into the space between wrapping tables 11. In this case receiving member 16 thus plays no part in the loading.

Because wrapping device 1 according to the invention is so compact, it can be assembled on a shared frame 4 with a baler 23, for instance a baler marketed by Massey Ferguson (www.masseyferguson.com) of the MF1800 type. This baler 23, which is driven from a tractor (not shown) by a power takeoff 24, has a pick-up part 25 with which mowed material is picked up from the ground G. This mowed material is pressed into rectangular or square bales 3 in baler 23, which are also tied together with twine in baler 23. These pressed bales 3 leave baler 23 through a delivery opening 26 to which the supply means 6 of wrapping device 1 connect.

Using these supply means 6 bales 3 are first transported rearward over segment 7, then upward by elevator conveyor 8 and finally forward by segment 9. At the end of supply means 6 bales 3 are transferred by distributing member 21 to one of the two pairs of wrapping tables 11 and there first received by receiving member 16. When bale 3 is clamped between wrapping tables 11, receiving member 16 is moved downward and wrapping arm 12 is started together with bar conveyors 15. Bale 3 is then rotated and wrapped in film 2. Once this wrapping is completed, wrapping arm 12 is stopped and receiving member 16 is moved upward again in order to receive bale 3, and then downward to set bale 3 down on the ground G. All movements and displacements of supply means 6, wrapping means 10 and the discharge means are carried out in a determined sequence by a suitable control of the drives of the different components. This control is provided by a controller {not shown here) , for instance a suitably programmed computer.

In another embodiment of wrapping device 1 according to the invention, which is mainly suitable for wrapping large bales 3, supply means 6 take a different form. Because such large bales 3, which are used as feed in regular livestock farming, can have a weight of several hundred kilos and dimensions of more than a metre in all directions, the elevator conveyor would have to take a very large and heavy form. Use is therefore made in this embodiment of the receiving members to carry bales 3 upward between the wrapping-clamping members 11.

Supply means 6 here comprise a roller track Q which connects to delivery opening 26 of baler 23, here for instance a so-called big baler from the assey Ferguson MF2100 series. This baler 23 is again assembled with wrapping device 1 on a shared frame 4, this time with a double-axle chassis 5 which is also provided with support wheels 49 (only one shown here) at the rear. Situated adjacently of roller track 48 is distributing member 21, here in the form of a slide 22 which is movable reciprocally between the left and right-hand side of roller track 48. The uprights 50 supporting slide 22 here move between the rollers of track 48.

Slide 22 pushes bales 3 from roller track 48 alternately onto the left or right-hand receiving member 16, which is then moved upward between wrapping-clamping members 11. Here bale 3 is once again clamped, rotated and wrapped in film 2. Finally, the film-wrapped bale 3 is received again by receiving member 16 and set down on the ground G. When bales 3 need not be wrapped in film, distributing member 21 remains stationary and bales 3 fall onto the ground G at the end of roller track 48.

In yet another embodiment of wrapping device 1 according to the invention, which is likewise mainly intended for processing large and heavy bales, the wrapping- clamping members 11 are embodied otherwise than in the above discussed wrapping devices. Each wrapping-clamping member 11 is formed here by a pair of rotatably driven rollers 51, which are mounted on either side in V-shaped end plates 52. These end plates 52 are in turn mounted in the frame (not shown) of wrapping device 1 for pivoting about respective shafts 53. Wrapping-clamping members 11 can hereby be moved between a loading and unloading position (fig. 8) in which rollers 51 are situated roughly at the level of supply means 6 (for instance a roller track 48), and an operative position in which the wrapping-clamping members 11 are directed vertically and clamp a bale 3 (fig. 9) . A guide ring 54 is mounted on the frame of wrapping device 1 around wrapping-clamping members 11. Movable along this guide ring 54 is an endless transport element 55, for instance a belt or chain, on which two film carriers 56 are mounted diametrically opposite one another. Each film carrier 56 comprises a roll of film 13 and a set of

tensioning and guide rollers 41 whereby film 2 is stretched for wrapping. In the shown embodiment guide ring 54 has in any case on its underside a somewhat flattened form, whereby wrapping-clamping members 11 can be arranged relatively low in the frame of wrapping device 1, for instance at or below the level of a delivery opening (not shown) of a baler.

Supply means 6 hereby do not need to carry bales 3 upward for wrapping. The upper side of guide ring 54 is also flattened in order to have film carriers 56 perform a uniform movement around the wrapping-clamping members 11 with bale 3 therebetween.

In the shown embodiment the distributing member 21 is once again embodied as a slide 22 which is reciprocally movable between the left and right-hand side of supply means 6.

In this embodiment a pressed bale 3 is pushed alternately to the left or the right by slide 22 of

distributing member 21 on the innermost of a pair of wrapping-clamping members 11 placed in the loading and unloading position. By driving the rollers 51 of this wrapping-clamping member 11 the bale 3 is transported further outward until it drops with an edge between

wrapping-clamping members 11. These wrapping-clamping members 11 are then set into their operative position by pivoting end plates 52 through about 90 degrees. Bale 3 is then clamped between wrapping-clamping members 11 and can be rotated about the horizontal longitudinal axis A by driving all rollers 51 in the same direction. Film carriers 56 are simultaneously moved along guide ring 54 to wrap the rotating bale 3 on all sides with film 2. Once bale 3 has been fully wrapped, the wrapping-clamping members 11 can be pivoted back to their loading and unloading position and rollers 51 can be driven such that bale 3 is re-placed again on roller track 48. This conveyor can then discharge bale 3 and place it on the ground.

Although the invention is described above with reference to a number of embodiments, it will be apparent that it is not limited thereto and can be varied in many ways within the scope of the following claims.