Reel-changing group for a wrapping apparatus and wrapping apparatus

Abstract

A reel-changing group (1) is disclosed that is configured to automatically change a reel in a rotating load wrapping apparatus (100) arranged for wrapping a film (2) around a rotating load by applying a certain number of wrapping turns, the reel-changing group (1) comprising: - a rotating support (3) rotatable around a rotation axis (R); - a first operating group (7) mounted on the rotating support (3) to be dragged into rotation around the rotation axis (R), the first operating group (7) comprising: - a first supporting and unwinding group (8) arranged for supporting and unwinding a first reel (9) of film (2) intended to wrap the load; - a first arm device (17) configured to be moved between a receiving position (S) in which it receives an initial strip of film (2) of the first reel (9) and a transfer position (T) in which it is placed near a gripper unit (103) located to the side of the load to transfer to the gripper unit (103) a portion of the initial strip of film (2) of the first reel (9); The reel-changing group (1) further comprises, at least one second operating group (18) mounted on the rotating support (3) to be rotated around the rotation axis (R), the at least one second operating group (18) comprising: - a second supporting and unwinding group (19) arranged for supporting and unwinding a second reel (20) of film (2) intended to wrap the load; - a second arm device (21) configured to be moved between a respective receiving position in which it receives an initial strip of film (2) of the second reel (20) and a respective transfer position in which the second arm device (21) is placed near the gripper unit (103) to transfer to the gripper unit (103) a portion of the initial strip of film (2) of the second reel (20); in which the first operating group (7) and the at least one second operating group (18) are mounted on the rotating support (3) so as to be alternatively moved by the rotating support (3) between an operating position (O) in which the first operating group (7) or the at least one second operating group (18) is enabled to transfer film (2) to the gripper unit (103) and a non-operating position (N) in which the first operating group (7) or the at least one second operating group (18) is disabled from transferring film (2) to the gripper unit (103).

Description

REEL-CHANGING GROUP FOR A WRAPPING APPARATUS AND WRAPPING APPARATUSBackground of the invention

[0001] The invention relates to a reel-changing group for a wrapping apparatus, in particular a wrapping apparatus of the rotating load type arranged for wrapping a film, coming from a reel, around a rotating load by applying a certain number of wrapping turns. The reelchanging group is configured, in particular, to perform an automatic reel change in this wrapping apparatus, for example in the event of the film finishing that makes up a reel, breakage of the film that makes up the reel or maintenance of an operating group that supports a reel.

[0002] The invention further relates to a wrapping apparatus equipped with this reelchanging group.

[0003] Wrapping apparatuses are known from the prior art that typically comprise a wrapping operating group that supports a reel of film to be wrapped around the load, so as to form an outer surface of the load, a series of braided wrapping turns or strips, owing to the combination of the movement in a vertical direction of the operating group and of the relative rotation between the latter and the load around a vertical wrapping axis.

[0004] The wrapping apparatuses of the rotating load type that are known from the prior art comprise a supporting turning table for supporting the load arranged for rotating the load around the vertical wrapping axis, whereas the wrapping operating group is positioned adjacent to the turning table and moved vertically with reciprocal motion along a column to cover a height of the load.

[0005] In order to increase productivity, wrapping apparatuses of the rotating load type are known that use a pair of wrapping operating groups positioned adjacent to and on opposite sides of the turning table and moved vertically with reciprocal motion along a respective column. The two operating groups are used simultaneously to wrap a load faster.

[0006] One defect of known rotating load wrapping apparatuses both of the type comprising a wrapping operating group and of the type comprising two wrapping operating groups that operate simultaneously, is that they require lengthy or anyway not insignificant downtime for replacing the reel of film once it has finished or become broken or to perform maintenance tasks on the wrapping operating group that supports the reel. This causes an extension of the time to complete a complete wrapping cycle for wrapping the load with the film.

[0007] In other words, the time for replacing a finished reel or maintaining the operatinggroup / s significantly affects the productivity of known wrapping apparatuses.

[0008] Also, replacing a finished reel is inconvenient because it is performed manually by one or more operators. This moreover causes a further reduction in productivity. In fact, the reels have a reduced dimension because they cannot exceed a given mass, in particular a mass of 25 kg, in order to be able to be moved manually (as given accident-prevention standards prescribe), without the help of a lifting device, and they accordingly finish rapidly, entailing frequent stops to change the finished reel.

[0009] DE 8911817 U1 discloses a wrapping device for wrapping packages with a film, which is provided with two supporting reel holders for a respective reel of film . The two reel holders are movable vertically on a column and are connected by a weight-compensating device to facilitate the manual handling of the reels of film, which are heavy. The weightcompensating device has at least one counter weight. A reel of film arranged on at least one reel holder forms the counterweight for at least one reel of film arranged on the other reel holder.

[0010] CN 116946490 A discloses a wrapping apparatus for wrapping a film of a reel around objects comprising a rotating platform installed on a frame to an edge of which a gripper is fixed for retaining a strip of film. A cutting device that is movable vertically with respect to the frame and provided at one end with a cutter for cutting the film is rotatably fixed to the frame. The cutting device is provided with a drive device that is in turn equipped with a clamping jaw, one side of the clamping jaw being movable horizontally to position, in use, a strip of film inside the gripper so as to transfer the strip of film to the gripper.

[0011] The prior art provides ample room for improvement.Summary of the invention

[0012] One object of the invention is to improve known wrapping apparatuses for wrapping a load with a film, improving in particular the method for replacing finished reels.

[0013] Another object is to carry out an automatic reel-changing group for a wrapping apparatus that enables productivity to be increased considerably compared with known wrapping apparatuses.

[0014] A further object is to devise a reel-changing group for an automatic wrapping apparatus that is convenient for operators to use.

[0015] Still another object is to obtain a reel-changing group that is simple and easily installable in already known rotating load wrapping apparatuses.

[0016] The objects of the invention, and still others, are achieved with a reel-changing groupfor a wrapping apparatus and with a rotating load wrapping apparatus according to what is defined in the appended claims.

[0017] In one embodiment, a reel-changing group is configured to automatically change a reel in a rotating load wrapping apparatus arranged for wrapping a film around a rotating load by applying a certain number of wrapping turns. The reel-changing group comprises:- a rotating support rotatable around a rotation axis;- a first operating group mounted on the rotating support to be dragged into rotation around the rotation axis, the first operating group comprising:- a first support and unwinding group arranged for supporting and unwinding a first reel of film intended to wrap the load;- a first arm device configured to be moved between a receiving position in which it receives an initial strip of film of the first reel and a transfer position in which it is placed near a gripper unit located to the side of the load to transfer to the gripper unit a portion of the initial strip of film of the first reel;The reel-changing group further comprises at least one second operating group mounted on the rotating support to be dragged into rotation around the rotation axis, the at least one second operating group comprising:- a second support and unwinding group arranged for supporting and unwinding a second reel of film intended to wrap the load;- a second arm device configured to be moved between a respective receiving position in which it receives an initial strip of film of the second reel and a respective transfer position in which the second arm device is placed near the gripper unit to transfer to the gripper unit a portion of the initial strip of film of the second reel;The first operating group and the at least one second operating group are mounted on the rotating support so as to be alternatively moved by the rotating support between an operating position in which the first operating group or the at least one second operating group is enabled to transfer film to the gripper unit and a non-operating position in which the first operating group or the at least one second operating group is disabled from transferring film to the gripper unit.

[0018] Owing to the reel-changing group according to the invention, which comprises at least two operating groups that are independent and ready for use, changing a reel is very rapid and this enables productivity to be increased considerably compared with knownwrapping apparatuses.

[0019] Also, owing to the reel-changing group according to the invention, productivity is increased because of the fact that machine downtime is substantially avoided. In fact, the arrangement of the at least two operating groups on a rotating support is such that whilst a first operating group is enabled to transfer the film to the gripper unit, a second operating group is far from the work zone in which the first operating group operates and can be subjected to reel maintenance or replacement operations.

[0020] Further, reel changing can be performed automatically by the wrapping apparatus, i.e. without manual intervention by an operator, following detection, by the wrapping apparatus, of a fault or malfunction condition in an operating group, or following detection of a reel finished condition of an operating group.

[0021] This reel-changing group is easy for operators to use because the reels can be smaller in dimension than those used in known rotating load wrapping apparatuses and, thus, with a lesser mass, which permits easier handling by the operator without productivity being decreased.

[0022] Lastly, the reel-changing group according to the invention has the advantage of being constructionally simple and easily installable in already known rotating load wrapping apparatuses because it is sufficient to install the two operating groups on the rotating support and position the rotating support to the side of a gripper unit with which known wrapping apparatuses are provided.

[0023] The same advantages as the above advantages are accordingly detectable in a wrapping apparatus provided with a reel-changing group according to the invention.Short description of the drawings

[0024] The invention can be better understood and implemented with reference to the attached drawings, which illustrate one embodiment thereof by way of non-limiting example, in which:Figure 1 is a perspective view of a wrapping apparatus configured to wrap a film around a load according to the invention comprising a reel-changing group according to the invention provided with the two operating groups;Figure 2 is the enlarged detail Q of Figure 1 showing an embodiment of a grasping device provided in each operating group;Figure 3 is a view like that of Figure 1 with the operating groups reversed;Figure 4 is a top plan view of the wrapping apparatus of Figure 1;Figure 5 is a side view of the wrapping apparatus of Figure 4;Figure 6 is a rear view of the wrapping apparatus of Figure 4;Figure 7 is a view like that of Figure 1 in which motor means for driving operating groups are shown;Figure 8 is the enlarged detail W of Figure 7 showing another embodiment of the grasping device of Figure 2.Detailed description

[0025] With reference to the attached Figures, for simplicity of exposure, identical elements of similar components, unless indicated differently, have been indicated by the same numbering.

[0026] With reference to the Figures mentioned above, a wrapping apparatus according to the invention has been indicated overall by 100, in particular a wrapping apparatus of the rotating load type, arranged for wrapping a film 2 around a rotating load by applying a certain number of wrapping turns or strips around the load and a reel-changing group according to the invention configured to automatically change a reel in a wrapping apparatus in particular a wrapping apparatus of the rotating load type, like, for example, the wrapping apparatus 100, has been indicated overall by 1.

[0027] The wrapping apparatus 100 can, in fact, comprise or be associated with the reelchanging group 1 according to the invention.

[0028] The wrapping apparatus 100 comprises a turning table 101 rotatable around a wrapping axis Y (Figures 4 and 5) and on which the load to be wrapped with the film 2 is arranged in use.

[0029] The turning table 101 thus acts as a support for the load and is configured to rotate the load around the wrapping axis Y during a wrapping cycle during which the load - when rotated by the turning table 101 - is wrapped with the wrapping film 2 in order to apply a set number wrapping turns of film 2 to the load.

[0030] The turning table 101 and the load are rotated around the wrapping axis Y along a wrapping direction, for example a clockwise rotation direction.

[0031] The film 2 is, in particular, unwound from a reel, as will be explained better in the description.

[0032] The wrapping apparatus 100 can comprise drive means 102 arranged for rotating the turning table 101 around the wrapping axis Y.

[0033] The drive means 102 can comprise a motor.

[0034] The wrapping axis Y is substantially vertical, i.e. substantially parallel to the gravity acceleration vector.

[0035] The load can be arranged resting on a support positionable on the turning table 101 like, for example, a pallet, i.e. can be a palletized load.

[0036] The load can be made up of a product or of a plurality of products, for example, grouped on a pallet.

[0037] The film 2 is made of an elastic and / or plastic material, for example the film can be a stretchable film having an elasticity that is such as to be able to be applied and shaped around the load and, at the same time, such as to keep together the latter stably. Further, the film can be, in particular, a macroperforated film and / or a biodegradable film and / or a thermosensitive film.

[0038] The reel-changing group 1 comprises a rotating support 3 rotatable around a rotation axis R.

[0039] The rotation axis R is substantially vertical, i.e. substantially parallel to the gravity acceleration vector.

[0040] The rotation axis R is thus substantially parallel to the wrapping axis Y.

[0041] The reel-changing group 1 can further comprise movement means 4 configured to rotate the rotating support 3.

[0042] The movement means 4 can comprise driving by a motor or a pneumatic drive.

[0043] In the embodiment illustrated in the Figures, the rotating support 3 comprises a slewing ring 5 (Figure 4) which is, for example, of toothed type and is engaged and rotated around the rotation axis R by a toothed pinion 6 driven by the movement means 4. The movement means 4 can comprise, for example in this embodiment, a motor.

[0044] When the electric power supply to the wrapping apparatus 100 is provided via cable, the rotating support 3 can be configured to rotate in a clockwise or anticlockwise rotation direction by an angle comprised between 0° and 180°.

[0045] When, on the other hand, the electric power supply to the wrapping apparatus 100 is provided by sliding contacts, the rotating support 3 can be configured to rotate between 0° and 360°.

[0046] The wrapping apparatus 100 further comprises a gripper unit 103 fitted near a first zone or first side 108 of the turning table 101 and configured to grasp a portion of an initial strip of the film 2 so as to be able to start up wrapping cycle for wrapping the load with the film.

[0047] In particular, during a wrapping cycle, the gripper unit 103 rotates integrally with the turning table 101 and in a start-up step of the wrapping cycle contributes to wrapping and unwinding the film 2 around the load by grasping and retaining the initial strip of film 2 whilst the gripper unit 103 is rotated.

[0048] During a wrapping cycle, the gripper unit 103 and the load thus move together with the turning table 101.

[0049] During the step of starting up the wrapping cycle, the gripper unit 103 is arranged to grasp the initial strip of film 2 and during a first step of the wrapping cycle the gripper unit 103 is arranged to retain the film 2 for a set number of rotations of the load around the wrapping axis Y.

[0050] The gripper unit 103 can comprise a first claw element 104 and a second claw element 105 that are hinged together.

[0051] In particular, the first claw element 104 and the second claw element 105 can be hinged near a respective end thereof.

[0052] The first claw element 104 and / or the second claw element 105 are / is connected to an actuating device 106, for example pneumatic actuating device 106, by which they are / it is drivable to move reciprocally, in particular rotate around a hinge axis that is substantially transverse, in particular perpendicular, to the wrapping axis Y.

[0053] The gripper unit 103 is in fact movable between a closed gripping position C (shown for example in Figure 2) in which the first claw element 104 is near the second claw element 105 to clamp a portion of the initial strip of film 2 therebetween and an open releasing position A (shown for example in Figure 3) in which the first claw element 104 is (at least partially) spaced apart from the second claw element 105 and the film 2 can be released by the gripper unit 103.

[0054] The closed gripping position C is adopted, in particular, during the start-up step of the wrapping cycle and during the first step of a first wrapping cycle that follows the startup step. In the first step, the turning table 101 and thus the gripper unit 103 is rotated a set number of times around the wrapping axis Y to wrap the load with wrapping turns formed by the film 2.

[0055] The open release position A is adopted, in particular, after the first step of a first wrapping cycle and during the rest of the first start-up cycle. Further, the open release position A can be maintained for the subsequent start-up cycles that follow a first wrapping cycle.

[0056] The gripper unit 103 further comprises a supporting and connecting structure 107 arranged for supporting the first claw element 104 and the second claw element 105 and connecting the first claw element 104 and the second claw element 105 to the turning table 101.

[0057] The supporting structure 107 can moreover support the actuating device 106.

[0058] The wrapping apparatus 100 can further comprise a cutting / welding / grasping group 109 comprising a cutting unit configured to cut the film 2, a welding unit configured to weld the film 2 to a wrapping turn of the film 2 around the load, and a further gripper unit configured to grasp during a wrapping cycle a strip of the film 2 intended to wrap a subsequent load.

[0059] The gripper unit 103 is used to retain a portion of the initial strip of film 2 (and is thus positioned in the closed gripping position C), in particular, the first time that the film 2 is used in a first wrapping cycle, for example when the film 2 is unwound for the first time from a virgin, i.e. not yet used, reel, or after breakage of the film 2. Also in particular, the gripper unit 103 is used in the aforesaid first step of only the first wrapping cycle. Subsequently, the gripper unit 103 is no longer used, i.e. can be arranged in the open release position A, but it is the further gripper unit of the cutting / welding / grasping group 109 that grasps a portion of film 2 and enables the wrapping cycle and the subsequent wrapping cycles to be continued until the film 2 stops, breaks or it is necessary to perform a maintenance task on the wrapping apparatus 100.

[0060] The start-up step is necessary when the film 2 is not yet stretched between components of the wrapping apparatus 100, i.e. between the reel-changing group 1 and the turning table 101.

[0061] The cutting / welding / grasping group 109 can be mounted, in particular, near a second side or second zone 110 of the turning table 101 opposite the first zone 108.

[0062] The cutting / welding / grasping group 109 is of known type and will not be disclosed further in detail below.

[0063] The wrapping apparatus 100 can further comprise a base 111 on which the turning table 101 and / or the rotating support 3 can be mounted.

[0064] The base 111 can be arranged resting on a floor by support means 112 for example provided with a plurality of feet.

[0065] The reel-changing group 1 further comprises a first operating group 7 mounted on the rotating support 3 to be dragged into rotation around the rotation axis R.

[0066] In fact, the first operating group 7 is mounted on the rotating support 3 so as to rotate integrally with the rotating support 3, if necessary, before the start of a first wrapping cycle, in particular before the start-up step of the first wrapping cycle.

[0067] The first operating group 7 comprises a first supporting and unwinding group 8 arranged for supporting and unwinding a first reel 9 of the film 2 intended to wrap the load.

[0068] The first operating group 7 is configured to transfer an initial strip of film 2 coming from the first reel 9 to the gripper unit 103. The initial strip of film 2 is a sort of baton that is passed from the first operating group 7 to the gripper unit 103.

[0069] Once the initial strip of film 2 is clamped in the gripper unit 103 (arranged in the closed gripping position C) the film 2 is stretched between the first operating group 7 and the gripper unit 103.

[0070] In use, the film 2 is wrapped around the load by rotation of the turning table 101 and thus, of the gripper unit 103, around the load 2 so as to apply a certain number of wrapping turns to the load.

[0071] During the wrapping cycle, the first operating group 7 is stationary, i.e. does not rotate whilst the load rotates.

[0072] In the first step of the first wrapping cycle, the film 2 is rotated around the wrapping axis Y and unwound from the first reel 9 owing to the gripper unit 103 arranged in the closed gripping position C. Afterwards, when the gripper unit 103 is arranged in the open release position A and a set number of turns of film has been applied around the load, the film 2 is rotated around the wrapping axis Y and unwound from the first reel 9 from the load during rotation.

[0073] The film 2 unwound from the first reel 9 can be stretched before being wrapped around the load and diverted to the load by one or more pre-stretching and transmission rollers, of known type, of the first support and unwinding group 8.

[0074] The reel-changing group 1 can further comprise a column 10 mounted on the rotating support 3 so as to rotate integrally with the rotating support 3.

[0075] In particular, the first operating group 7 is mounted slidingly on the column 10 so as to translate along a first vertical direction DI.

[0076] The first vertical direction DI is substantially parallel to the wrapping axis Y and / or to the rotation axis R.

[0077] In use of the first operating group 7, the load is rotated around the vertical wrapping axis Y, whilst the supporting and unwinding group 8 is moved vertically with reciprocalmotion. The distance travelled by the supporting and unwinding group 8 along the first vertical direction DI depends on a height of the load so that the first operating group 7 can apply, if desired, the wrapping turns of film 2 on the entire height of the load.

[0078] In particular, the first operating group 7 is movable between a lower position H (shown for example in Figure 5), in which it is arranged at a first height on the column 10, and an upper position, which is not illustrated in the Figures, in which it is arranged at a second height on the column 10 that is greater than the first height.

[0079] During operation of the first operating group 7, the combination of the movement in a vertical direction of the first operating group 7 and of the relative rotation between the latter and the load with respect to the wrapping axis Y by virtue of the rotation of the turning table 101) enables the load to be wrapped with a series of wrapping turns or strips of film 2.

[0080] The first operating group 7 further comprises a first arm device 17 configured to be moved between a receiving position S (shown for example in Figure 3) in which it receives an initial strip of the film 2 of the first reel 9 and a transfer position T (shown for example in Figure 1) in which at least one part thereof placed near of the gripper unit 103, which is located to the side of the turning table 101 and accordingly alongside the load (when arranged on the turning table 101), to transfer to the gripper unit 103 a portion of the initial strip of film 2 of the first reel 9.

[0081] The reel-changing group 1 further comprises, at least one second operating group 18.

[0082] The at least one second operating group 18 is, in particular, functionally and structurally identically to the first operating group 7.

[0083] The at least one second operating group 18 is used to provide the film 2 alternatively to the first operating group 7.

[0084] In the embodiment shown in the Figures, there is a first operating group 7 and a second operating group 18, but in other embodiments one or more further operating groups are possible, in addition to the first operating group 7 and to the second operating group 18, each being functionally and structurally identical to the first operating group 7.

[0085] Also the second operating group 18 is mounted on the rotating support 3 to be dragged into rotation around the rotation axis R.

[0086] In particular, also the second operating group 18 is mounted on the rotating support 3 so as to rotate integrally with the rotating support 3, if necessary, before the start of a first wrapping cycle, in particular before the start-up step of the first wrapping cycle.

[0087] In particular, when the rotating support 3 rotates, both the first operating group 7 and the second operating group 18 rotate integrally.

[0088] The at least one second operating group 18 comprises a second supporting and unwinding group 19 arranged for supporting and unwinding a second reel 20 of the film 2 intended to wrap the load. In particular, the second reel 20 is a spare reel that is used when the first reel 9 is finished or broken, or in the event of malfunction or fault of the first operating group 7.

[0089] The at least one second operating group 18 further comprises a second arm device 21 which is also configured to be moved between a respective receiving position in which it receives an initial strip of the film 2 of the second reel 20 and a respective transfer position in which the second arm device 21 is placed near the gripper unit 103 located to the side of the turning table 101 and accordingly alongside the load (when arranged on the turning table 101), to transfer to the gripper unit 103 a portion of the initial strip of film 2 of the second reel 20.

[0090] The first operating group 7 and the at least one second operating group 18 are mounted on the rotating support 3 so as to be alternatively moved by the rotating support 3 between an operating position O in which the first operating group 7 or the at least one second operating group 18 is enabled to transfer film to the gripper unit 103 and a nonoperating position N in which the first operating group 7 or the at least one second operating group 18 is disabled from transferring film to the gripper unit 103.

[0091] In the respective receiving position S the first arm device 17 and the second arm device 21 are arranged alongside the supporting and unwinding group 8. This receiving position S can be adopted both in the operating position O or in the non-operating position N.

[0092] If more than two operating groups are present (each being substantially similar to the first operating group 7), these operating groups can be mounted on the rotating support 3 so that only one operating group a time is positioned in the operating position O whilst the other operating groups are positioned in the non-operating position N.

[0093] In the operating position O a (sole) arm device 17, 21 faces and is nearer the gripper unit 103 and can transfer the initial strip of film coming from the respective reel 9, 20, when driven from the receiving position S to the transfer position T, for example by a rotation. On the other hand, in the non-operating position O the other arm device(s)17, 21 does (do) notfaces(face) the, and is(are) further from the, gripper unit 103 and cannot transfer the initial strip of film coming from the respective reel 9, 20.

[0094] In Figure 1, the second reel 20 is shown partially used or finished whereas in Figure 3 the second reel 20 is shown virgin, i.e. new, still to be used.

[0095] The Figures show, in particular, the first operating group 7 in the operating position O, in which the first arm device 17 faces and is nearer the gripper unit 103 and can transfer the initial strip of film coming from the first reel 9, whereas the second operating group 18 is shown in the non-operating position N in which the second arm device 21 does not face and is further from the gripper unit 103 and cannot transfer the initial strip of film coming from the second reel 20.

[0096] In particular, the first operating group 7 and the at least one second operating group 18 can be mounted opposite a plane P passing through the rotation axis R, so that when the first operating group 7 is in the operating position O the at least one second operating group 18 is in the non-operating position N, and vice versa.

[0097] The plane P can be defined by a photoelectric safety barrier arranged for separating a work zone in which an operating group operates to wrap the film around the load from a rest zone in which the other operating group(s) can be subjected to reel replacement and / or maintenance tasks.

[0098] In this manner, when the first operating group 7 or the at least one second operating group 18 (or the other operating groups that are possibly present) is in the non-operating position N, it is outside the work zone in which an operating group operates 7, 18 arranged in the operating position O and can thus be subjected to maintenance or replacement operations whilst the operating group is in use, i.e. when the wrapping apparatus 100 is driven to wrap the load with the film 2. Also, in the non-operating position N it is possible to remove a core of a finished reel from the operating group 7, 18 that is not in use, still whilst the operating group 7, 18 is in use, i.e. when the wrapping apparatus 100 is driven to wrap the load with the film 2. This enables stops of the wrapping apparatus 100 to be avoided to perform reel maintenance / replacement / change tasks on the reel of the operating group not in use, and the productivity of the wrapping apparatus 100 is accordingly significantly increased compared with prior art wrapping apparatuses.

[0099] The first arm device 17 and the second arm device 21 (and possibly each of the arm devices of other operating groups that are possibly present) are rotatable around a respective axis LI, L2 by an angle comprised between 0° and 90°, in particular comprised between 70°and 80°, in function of a position of the gripper unit 103 to convey the initial strip of film 2 between the respective receiving positions S and the respective transfer positions T.

[0100] Like the first operating group 7, also the second operating group 18 is configured to transfer an initial strip of film 2 coming from the second reel 20 to the gripper unit 103. Also in this case, the initial strip of film 2 is a sort of baton that is passed from the second operating group 18 to the gripper unit 103 when the second operating group 18 is positioned in the operating position O, in particular following rotation of the rotating support 3.

[0101] The first operating group 7 or the second operating group 18 (or another operating group that is possibly present) is used to transfer the film from the respective arm device 17, 21 to the gripper unit 103 and is accordingly used, in particular, the first time that a film 2 unwound from a reel is used, for example because it is unwound from a virgin reel, either following breakage of the film 2, or after the first operating group 7 or the second operating group 18 has been subjected to a maintenance or replacement operation.

[0102] In use, in fact, for example when the first reel 9 finished after the first operating group 7, the rotating support 3 rotates by positioning the first operating group 7 (which was previously in the operating position O) in the non-operating position N and simultaneously positioning the second operating group 18 (which was previously in the non-operating position N) in the operating position O. In the operating position O the second arm device 21 is then arranged (for example rotated) in the respective transfer position to transfer the initial strip of film 2 to the gripper unit 103.

[0103] Once the initial strip of film 2 coming from the second reel 20 is clamped in the gripper unit 103 (arranged in the closed gripping position C) the film 2 is stretched between the second operating group 18 and the gripper unit 103.

[0104] As also mentioned in the first operating group 7, when the second operating group 18 is used, the film 2 unwound from the second reel 20 (when the second operating group 18 is positioned in the operating position O) is wrapped around the load by rotation of the turning table 101 and thus, of the gripper unit 103, around the load 2 so as to apply a certain number of wrapping turns to the load.

[0105] During the wrapping cycle, also the second operating group 18 is stationary, i.e. does not rotate whilst the load rotates.

[0106] When the second operating group 18 is arranged in the operating position O and is in use, in the first step of the first wrapping cycle, the film 2 is dragged into rotation around the wrapping axis Y and unwound from the second reel 20 owing to the gripper unit 103arranged in the closed gripping position C. Afterwards, when the gripper unit 103 is arranged in the open release position A and a set number of turns of film has already been wrapped around the load, the film 2 is dragged into rotation around the wrapping axis Y and unwound from the second reel 20 by the load itself.

[0107] Also the film 2 unwound from the second reel 20 can be stretched before being wrapped around the load and diverted towards the load by one or more pre-stretching and return roller, of known type, of the second support and unwinding group 19.

[0108] The reel-changing group 1 can further comprise a further column 22 mounted on the rotating support 3 so as to rotate integrally with the rotating support 3.

[0109] In use, the rotating support 3 is rotated to enable the first operating group 7 or the second operating group 18 to unwind / feed the film 2 from the first reel 9 or from the second reel 20.

[0110] In particular, the second operating group 18 is mounted slidingly on the column 22 so as to translate along a second vertical direction D2.[OHl] The second vertical direction D2 is substantially parallel to the wrapping axis Y and / or to the rotation axis R and / or to the first vertical direction DI .

[0112] In an embodiment that is not illustrated, the second operating group 18 can be slidably mounted on the column 10.

[0113] During use of the second operating group 18, the load is rotated around the vertical wrapping axis Y, whereas the second supporting and unwinding group 19 is moved vertically with reciprocal motion. The distance travelled by the second supporting and unwinding group 19 along the second vertical direction D2 is function of a height of the load so that the second operating group 18 can apply, if necessary, the film 2 wrapping turns to an entire height of the load.

[0114] In particular, the second operating group 18 is movable between a respective lower position in which it is arranged at a first height on the further column 22, and an upper position, which is not illustrated in the Figures, in which it is arranged at a second height on the further column 22 that is greater than the first height.

[0115] Also during operation of the second operating group 18, the combination of the movement in a vertical direction of the second operating group 18 and of the relative rotation between the latter and the load with respect to the wrapping axis Y (by virtue of the rotation of the turning table 101) enables the load to be wrapped with a series of wrapping turns or strips of film 2 coming from the second reel 20.

[0116] In the embodiment illustrated in the Figures where each operating group 7, 18 is mounted on a respective column 10, 22, each operating group 7, 18 can comprise a respective carriage 11 comprising a respective frame 12 on which a plurality of respective revolving, in particular idling, elements 13 are mounted, arranged for rolling along an outer surface 14 of the respective column 10, 22, when the carriage 11 is driven by motor means 15 along the respective vertical direction DI, D2.

[0117] The motor means 15 is in fact arranged for sliding the first operating group 7 and / or the second operating group 18 respectively along the first vertical direction DI and along the second vertical direction D2, in particular to vary vertical positioning of the first operating group 7 and / or the second operating group 18.

[0118] The motor means 15 is suitable for moving the first operating group 7 and / or the second operating group 18, in particular, during a wrapping cycle between the respective lower position and the respective upper position to cover a desired height of a load to be wrapped or during a reel change cycle to take the first reel 9 and / or the second reel 20 to a desired height, for example with respect to the rotating support 3.

[0119] The motor means 15 can be mounted on a support element 32 mounted in turn on the rotating support 3 and on which the column 10 and the further column 22 are mounted.

[0120] The motor means 15 is shown in Figure 7, whereas in Figures 1 to 6 it is not shown although it can be present.

[0121] The support element 32 can comprise a parallelpipedon block as in the illustrated embodiment in Figure 7.

[0122] The motor means 15 can comprise a pair of motors 30, each motor 30 being arranged for driving vertically a respective operating group 7, 18. The pair of motors 30 is shown in Figure 7, whereas in Figures 1 to 6 is not shown although it may be present. Each frame 12 is connected (in particular stiffly) to a support frame 16 of the respective supporting and unwinding group 8, 19.

[0123] Each support frame 16 can comprise a respective plate element 23 on which components of the respective supporting and unwinding group 8, 19 are mounted, like, for example, the first reel 9 and the second reel 20.

[0124] The first arm device 17 and the second arm device 21 (and possibly each of the arm devices of other operating groups that are possibly present) are mounted rotatably on the respective support frame 16 (in particular on the plate element 23).

[0125] The first arm device 17 and the second arm device 21 can be arranged, at least partially, at a greater height than a further end of the gripper unit 103 (in particular opposite the end in which are mutually hinged), when the respective operating groups 7, 18 are positioned in the operating position O, in particular in the lower position H.

[0126] The first arm device 17 and the second arm device 21 can each comprise a rod element 24 rotatably mounted respectively on the first supporting and unwinding group 8 and on the second supporting and unwinding group 19 so as to rotate around the respective axis LI, L2 so as to approach or move away from the gripper unit 103.

[0127] In particular, each rod element 24 is connected to the respective support frame 16, in particular to the plate element 23.

[0128] Each rod element 24 can comprise a bar that is mounted on the support frame 16 and projects from the latter.

[0129] The first arm device 17 and the second arm device 21 can each further comprise at least one grasping device 25 projecting from a lower face of the rod element 24 so as to protrude downwards. The at least one grasping device 25 is configured to receive and retain the initial strip of film coming from the respective first reel 9 or second reel 20.

[0130] In particular, the initial strip of film coming from the first reel 9 or from the second reel 20 is collected, for example by an operator, and inserted into the grasping device 25.

[0131] In the embodiment shown in the Figures, the first arm device 17 and the second arm device 21 each comprise, two grasping devices 25 mounted spaced apart on the respective rod element 24, but in other embodiments, there can be one sole grasping device 25 or more than two grasping devices 25.

[0132] In particular, the grasping device / s 25 are mounted on the rod element 24 in a fixed position, so as not to move linearly along the rod element 24.

[0133] The grasping device 25 can comprise a pair of finger elements 26 configured to retain between them the initial strip of film 2. The pair of finger elements 26 can in fact be movable between a grasping position F (shown for example in Figures 2 and 8) in which they retain together the strip of film and a rest position G (shown for example in Figure 1 for the second operating group 18) in which they do not retain between them the strip of film 2.

[0134] The finger elements 26 can be (mutually) hinged, for example at a respective end thereof or in an intermediate position between two opposite ends thereof. In the rest position G, the finger elements 26 can be nearer than the grasping position F because in the graspingposition F the finger elements 26 are, at least partially, reciprocally moved away from the initial strip of film 2 positioned therebetween.

[0135] Figures 2 and 8 show two enlarged details of two embodiments of the grasping device 25.

[0136] With reference in particular to Figures 7 and 8, each grasping device 25 can further comprise an elastic element associated with the pair of finger elements 26 and arranged for urging the finger elements 26 constantly to the rest position G. In this case, driving finger elements is passive. In fact, in this case the initial strip of film is inserted between the pair of finger elements (for example by an operator) overcoming the elastic force of the elastic element and remains retained there by the elastic force until the gripper unit 103 grasps a portion of this initial strip. At this point, the arm device 17, 21 is driven vertically and the initial strip of film 2 disengages from the grasping device 25 remaining retained only by the claw elements 104, 105 of the gripper unit 103.

[0137] The elastic element can comprise a spring configured to stretch when the finger elements 26, or a portion thereof, are moved apart from one another.

[0138] With reference to the embodiment of grasping device 25 of Figures 7 and 8, each grasping device 25 comprises a fixed finger element 26 and a movable finger element 26 driven by a pressing spring (like a peg or clip for hanging washing). At least one portion of the fixed finger element 26 of each grasping device 25 can be fixed to the rod element 24 whereas the other finger element 26 is, in use, movable and drivable by the spring. In the case of the embodiment of Figures 7 and 8, in use, the vertical movement of the operating groups 7, 18, when the claw elements 104, 105 of the gripper unit 103 are clamped (i.e. are in the closed gripping position C), means that the initial strip of the film 2 separates from the gripper unit 103, because the upward pulling force overcomes the retaining force of the spring.

[0139] Alternatively, driving the finger elements 26 can be active, as, for example, in the embodiment of grasping device 25 of Figures 1 to 6. In this case, driving the finger elements 26 between the grasping position F and the rest position G is of pneumatic and / or mechanical type. For example, by delivering compressed air the finger elements 26 can be driven to approach one another and reach the grasping position F (i.e. they close) or to move away from one another (i.e. they open) and reach the rest position G. In this case, each grasping device 25 can comprise a two-finger electric gripper.

[0140] In the respective transfer position T at least one portion of the rod element 24 is arranged at a greater height than the further end of the gripper unit 103 to enable the gripper unit 103 to grasp a portion of the initial strip of film 2 that hangs below the rod element 24, when the initial strip of film 2 is positioned between the finger elements 26, as shown in particular in the Figure 2.

[0141] The gripper unit 103 is in fact configured to grasp an initial strip of said film when the first arm device 17 is in the transfer position T or when the second arm device 21 is in the respective transfer position. Once the gripper unit 103 has grasped the initial strip of film 2 (coming from the first reel 9 or from the second reel 20) it is possible to start up the wrapping cycle of the load by the film coming from the first reel 9 or from the second reel 20.

[0142] Each operating group 7, 18 can further comprise respective actuating means arranged for moving the respective arm device between the respective receiving position S and the respective transfer position T.

[0143] In particular, the first operating group 7 can further comprise first actuating means 27 arranged for moving the first arm device 17 between the receiving position S and the transfer position T and the second operating group 18 can further comprise second actuating means 28 arranged for moving the second arm device 21 between the respective receiving position and the respective transfer position.

[0144] The first actuating means 27 and / or the second actuating means 28 can be of electromechanical or pneumatic type.

[0145] In the embodiment illustrated in the Figures, the first actuating means 27 and the second actuating means 28 each comprise, a linear drive device 29 like, for example, a linear pneumatic actuator (for example a pneumatic cylinder) provided with a liner 31 mounted on the support frame 16 and with a stem 33 connected to the rod element 24 to cause rotation of the respective arm device 17, 21 around the respective axis LI, L2 to move an end of the rod element 24 towards / away from the gripper unit 103.

[0146] The wrapping apparatus 100 can further comprise sensor means arranged for detecting a film breakage or finished condition coming from a reel (first reel 9 or second reel 20) and / or an about to finish film condition (for example they detect whether a set quantity of film remains, for example 10% of film of the film content of the original reel).

[0147] The sensor means can comprise, for example, one or more rotation speed sensors associated with the first reel 9 and with the second reel 20. When the rotation speed detectedin a reel of an operating group in use is nil means that this reel does not rotate, i.e. the film 2 is finished or broken.

[0148] The wrapping apparatus 100 can further comprise a control unit configured to drive directly or indirectly, the components of the reel-changing group 1, the gripper unit 103, the turning table 101 and the components of the cutting / welding / grasping group 109 and other possible components of the wrapping apparatus 100.

[0149] The control unit is further configured to synchronize the different drive steps of the components of the reel-changing group 1, of the gripper unit 103, of the turning table 101 and of the cutting / welding / grasping group 109.

[0150] The control unit can comprise a programmable logic controller (PLC).

[0151] The control unit is further configured to receive data detected by the sensor means, process the data and possibly transmit drive command to the reel-changing group 1 in order to move the drive appropriately.

[0152] For example, following receipt of the data from the sensor means on film breakage or finished film on an operating group 7, 18, for example the first operating group 7, the wrapping apparatus 100 can intervene to change the reel, rotating the rotating support 3 to move the first operating group 7 from the operating position O to the non-operating position N and the second operating group 18 (with the initial strip of film 2 coming from the second reel 20 inserted into each grasping device 25 present) from the non-operating position N to the operating position O. The second operating group 18 can then transfer the initial strip of film coming from the second reel 20 to the gripper unit 103.

[0153] This allows an automatic reel change, i.e. without the presence of an operator.

[0154] The control unit can comprise a two-way wireless communication arranged for communicating with components of the wrapping apparatus 100.

[0155] Operation of the reel-changing group 1 and of the wrapping apparatus 100 with which such a reel-changing group 1 can be associated is now disclosed below.

[0156] In particular, a start-up step will be first disclosed of a wrapping cycle of the film 2 around the load in which an operating group 7, 18 and the gripper unit 103 are enabled to transfer an initial strip of the film 2 from the operating group 7, 18 to the gripper unit 103. The start-up step is preparatory to be being able to start the actual wrapping cycle of wrapping the film around the load.

[0157] A first step of the wrapping cycle for wrapping the film 2 around the load will be subsequently disclosed that follows the start-up step, during which the operating group 7, 18is used only to unwind the reel 9, 20, and the gripper unit 103 retains the initial strip of the film 2 for a set number of rotations of the load around the wrapping axis Y.

[0158] In the start-up step of a wrapping cycle, when it is necessary to connect an initial strip of film 2, for example from a first reel 9, in particular following breakage of the film of the first reel 9, or finishing the film of another reel used previously, for example the second reel 20, the reel-changing group 1 checks whether an operating group with a non-finished reel is present in the operating position O. If the sensor means has to detect a film finished condition in a previously used reel, the reel-changing group 1 rotates the rotating support 3 to carry an operating group with an intact and non-finished reel, for example the first operating group 7, in the operating position O. Automatically, the second operating group 18 (with the second finished reel 20) is taken to the non-operating position N.

[0159] Whilst the second operating group 18 is in the non-operating position N, it is possible to change the second reel 20 that has possibly finished and / or perform a maintenance task on the film on the second supporting and unwinding group 19.

[0160] The first operating group 7 is taken, if it is not already there, to the lower position H by the motor means 15.

[0161] Reference will be made below to the operation of the first operating group 7, the operation of the second operating group 18 (or of other operating groups that are possibly present) being completely similar to that of the first operating group 7. This is possible owing to the arrangement opposite the plane P of the of the first operating group 7 and of the second operating group 18 on the rotating support 3 that enables operating group that is not in use, in this case the second operating group 18, to be positioned far from the work zone in which the first operating group 7 operates.

[0162] In the operating position O, the first operating group 7 faces the gripper unit 103. The first arm device 17 is in the receiving position S in which it receives (or has already received in the non-operating position N) an initial strip of film of the first reel 9. In particular, in the receiving position S the initial strip of film is inserted and retained in the grasping devices 25 that are present.

[0163] The gripper unit 103 is in the open release position A.

[0164] From the receiving position S the first arm device 17 is then taken, in particular rotated by the linear drive device 29, in the transfer position T, in which at least one portion of the rod element 24 is near the gripper unit 103 and the strip of film is positioned at and above the gripper unit 103.

[0165] Subsequently, the gripper unit 103 is taken from the open release position A to the closed gripping position C in which the first claw element 104 and the second claw element 105 clamp between them a portion of initial strip of film (Figure 2).

[0166] At this point, the first operating group 7 is moved along the first vertical direction DI upwards at least by a portion that enables the initial strip of film to be removed from each grasping device 25 present. In the case of grasping devices 25 of passive type, the initial strip of film disengages from each grasping device 25 present when the first operating group 7 moves along the first vertical direction DI upwards by an appropriate amount, whereas in the case of a grasping device 25 of active type, for example, the finger elements 26 moved away from one another (for example along a transverse direction, in particular perpendicular, to the direction of prevalent extent of the rod element 24) to reach the rest position G and thus let the initial strip of film 2 go. The initial strip of film coming from the first reel 9 is now retained by only gripper unit 103 and the first arm device 17 is no longer used. The start-up step has ended. The first operating group 7 is from now on used to unwind of the first reel 9 and can be driven along the first vertical direction DI to cover a height of the load.

[0167] Definitively, the operating group in use, in this case the first operating group 7, is configured to connect the film 2 of the first reel 9 of the supporting and unwinding group 8 to the turning table 101, when the supporting and unwinding group 8 with the first new reel 9 aboard, or with the film broken in a previous wrapping cycle, has never been connected to the turning table 101.

[0168] The gripper unit 103 can now start up the wrapping cycle because the film 2 is taut between the first supporting and unwinding group 8 and the gripper unit 103.

[0169] The control unit then rotates the turning table 101 (and thus the load and the gripper unit 103 that is retaining a portion of the initial strip of film of the first reel 9) around the wrapping axis Y.

[0170] In a first step of the wrapping cycle, the film 2 is rotated around the wrapping axis Y and unwound from the first reel 9 owing to the gripper unit 103 that is maintained in the closed gripping position C for a set number of rotations around the wrapping axis Y.

[0171] After a set number of wrapping turns of the film has been applied to the load, the gripper unit 103 is taken from the closed gripping position C to the open release position A. It is not in fact more necessary for the gripper unit 103 to retain the strip of film, which inthe meantime has been covered by some wrapping turns that retain the strip of film against the load even when the gripper unit 103 is arranged in the open release position A.

[0172] At this point, the wrapping cycle continues with wrapping the load by further wrapping turns up to a set number whereas the first operating group 7 is moved vertically along the vertical direction DI along the column 10 to cover height wrapping turns of the load.

[0173] Near the end of the wrapping cycle, the turning table 101 is stopped and the control unit drives the cutting / welding / grasping unit 109 in a known manner to grasp a tail of the film (by the further gripper unit), which will be become the initial strip or head of the film 2 of a subsequent wrapping cycle, cut the film (by the cutting unit) so as to separate the tail of film from the rest of film wrapped around the load and weld the film 2 to a wrapping turn of the film 2 around the load (by the welding unit).

[0174] In the subsequent wrapping cycles in which the first reel 9 is used, the first arm device 17 and the gripper unit 103 are no longer used. It is, in fact, the further gripper unit that tensions the film between the first supporting and unwinding group 8 and the turning table 101.

[0175] When it is necessary to replace the first reel 9, for example because the sensor means has detected a film finished or film about to be finished or film broken condition, and / or it is necessary to perform a maintenance task on the first operating group 7, the control unit rotates the rotating support 3 for example by 180°, to take the second operating group 18 to the operating position O and automatically take the first operating group 7 to the nonoperating position N.

[0176] At this point, the operation of the second operating group 18 continues as disclosed above in relation to the first operating group 7.

[0177] Owing to the fact that the operating groups (the first operating group 7, the second operating group 18 and possibly other operating groups that are possibly present) are independent in operation and at least one is positioned in the non-operating position N ready for use, reel changing is very rapid and this enables productivity to be increased considerably compared with known wrapping apparatuses.

[0178] Further, again owing to the fact that at least one operating group is positioned in the non-operating position N ready for use, it is possible to use reels with a lower mass than the reels used in known wrapping apparatuses, thus facilitating operators who have to handlethe reels manually and without substantially affecting the productivity of the wrapping apparatus 100.

[0179] The opposite arrangement of the two operating groups 7, 18 on the rotating support 3 enables the operating group that is not in use to be subjected to maintenance or replacement tasks. This is also found in cases in which the reel-changing group 1 comprises more than two operating groups. For example, in the case of three operating groups, the operating groups can be mounted on the rotating support 3 (for example each on a respective column) so as to have an angular arrangement, or adopt an angular arrangement (for example following a rotation or one or more groups around a respective rotation axis) that enables a single operating group to be positioned in the operating position O and the other operating groups to be positioned in the non-operating position N.

[0180] In this manner, machine downtime can be substantially avoided and productivity is increased further.

[0181] Owing to the reel-changing group 1 according to the invention, to the sensor means and to the control unit, reel changing can be performed automatically by the wrapping apparatus 100, i.e. without manual intervention by an operator. The operator can intervene to insert the initial strip of the film suitably into each grasping device 25 present (for example the operator can bundle an initial portion of film) so that when the arm device rotates it remains completely aligned and stretched below the rod element 24.

[0182] The motor means 15 contributes to making a reel change cycle automatic owing to suitable vertical positioning of the operating groups 7, 18 and thus of a new reel 9, 20, on the respective column 10, 22 without intervention by an operator during the reel change cycle.

[0183] In order to install the reel-changing group 1 in a wrapping apparatus 100, it is sufficient to position the rotating support 3 alongside the gripper unit 103. This installation is thus rather simple.

[0184] From what has been set out above, it is clear that the reel-changing group 1 according to the invention successfully achieves all the set objects mentioned previously.

[0185] What has been disclosed and shown in the enclosed drawings has been provided by way of illustration of the innovative features of the reel-changing group 1.

[0186] Variations on and / or additions to what has been disclosed and illustrated in the attached drawings are possible.

Claims

CLAIMS1. Reel-changing group (1) configured to automatically change a reel in a rotating load wrapping apparatus (100) arranged for wrapping a film (2) around a rotating load by applying a certain number of wrapping turns, said reel-changing group (1) comprising:- a rotating support (3) rotatable around a rotation axis (R);- a first operating group (7) mounted on said rotating support (3) to be dragged into rotation around said rotation axis (R), said first operating group (7) comprising:- a first support and unwinding group (8) arranged for supporting and unwinding a first reel (9) of said film (2) intended to wrap said load;- a first arm device (17) configured to be moved between a receiving position (S) in which it receives an initial strip of said film (2) of said first reel (9) and a transfer position (T) in which it is placed near a gripper unit (103) located next to said load to transfer to said gripper unit (103) a portion of said initial strip of said film (2) of said first reel (9); said reel-changing group (1) being characterized in that it further comprises at least one second operating group (18) mounted on said rotating support (3) to be dragged into rotation around said rotation axis (R), said at least one second operating group (18) comprising:- a second supporting and unwinding group (19) arranged for supporting and unwinding a second reel (20) of film (2) intended to wrap said load;- a second arm device (21) configured to be moved between a respective receiving position in which it receives an initial strip of said film (2) of said second reel (20) and a respective transfer position in which said second arm device (21) is placed near said gripper unit (103) to transfer to said gripper unit (103) a portion of said initial strip of said film (2) of said second reel (20); in which said first operating group (7) and said at least one second operating group (18) are mounted on said rotating support (3) so as to be alternatively moved by said rotating support (3) between an operating position (O) in which said first operating group (7) or said at least one second operating group (18) is enabled to transfer said film (2) to said gripper unit (103) and a non-operating position (N) in which said first operating group (7) or said at least one second operating group (18) is disabled from transferring said film (2) to said gripper unit (103), said reel-changing group (1) further comprising:- a column (10) mounted on said rotating support (3) so as to rotate integrally with said rotating support (3), said first operating group (7) being slidingly mounted on said column (10) so as to translate along a first vertical direction (DI);- at least one further column (22) mounted on said rotating support (3) so as to rotate integrally with said rotating support (3), said at least one second operating group (18) being slidingly mounted on said further column (22) so as to translate along a second vertical direction (D2) substantially parallel to said first vertical direction (DI); and- motor means (15) arranged for sliding said first operating group (7) and / or said second operating group (18) respectively along said first vertical direction (DI) and along said second vertical direction (D2) to vary vertical positioning of said first operating group (7) and / or of said second operating group (18).

2. Reel-changing group (1) according to claim 1, wherein said first operating group (7) and said at least one second operating group (18) are mounted opposite a plane (P) passing through said rotation axis (R), so that when said first operating group (7) is in said operating position (O) said at least one second operating group (18) is in said non-operating position (N) and vice versa.

3. Reel-changing group (1) according to any one of the preceding claims, wherein said first arm device (17) and said second arm device (21) are rotatable around a respective axis (LI, L2) by an angle comprised between 0° and 90°, in particular comprised between 70° and 80°, in function of a position of said gripper unit (103) to convey said initial strip of said film (2) respectively between said receiving position (S) and said transfer position (T) and between said respective receiving position and said respective transfer position.

4. Reel-changing group (1) according to any one of the preceding claims, wherein said first arm device (17) and said second arm device (21) each comprise:- a rod element (24) rotatably mounted respectively on said first supporting and unwinding group (8) and on said at least one second supporting and unwinding group (19) so as to rotate around said respective axis (LI, L2) so as to approach or move away from said gripper unit (103); and- at least one grasping device (25) projecting from a lower face of said rod element (24) so as to protrude downwards, said at least one grasping device (25) being configured to receive and retain said initial strip of said film (2).

5. Reel-changing group (1) according to claim 4, wherein said at least one grasping device (25) comprises a pair of finger elements (26) configured to retain together said initial strip of said film (2), said pair of finger elements (26) being movable, passively or actively, between a grasping position (F) in which they do retain between them said strip of said film (2) and a rest position (G) in which they do not retain between them said strip of said film6. Reel-changing group (1) according to claim 5, wherein said grasping device (25) further comprises an elastic element associated with said pair of finger elements (26) and arranged for constantly urging said finger elements (26) to said rest position (G).

7. Reel-changing group (1) according to any one of the preceding claims, wherein said first operating group (7) further comprises, first actuating means (27) arranged for moving said first arm device (17) to said receiving position (S) and said transfer position (T) and in which said second operating group (18) further comprises, second actuating means (28) arranged for moving said second arm device (21) between said respective receiving position and said respective transfer position, said first actuating means (27) and said second actuating means (28) being of electromechanical or pneumatic type.

8. Reel-changing group (1) according to any one of the preceding claims, and further comprising movement means (4) configured to rotate said rotating support (3), said movement means (4) comprising driving by a motor or a pneumatic drive.

9. Reel-changing group (1) according to any one of the preceding claims, wherein said motor means (15) comprises a pair of motors (30), each motor (30) being arranged for driving vertically a respective operating group (7, 18).

10. Rotating load wrapping apparatus (100) a arranged for wrapping a film (2) around a rotating load by applying a certain number of wrapping turns comprising:- a reel-changing group (1) according to any one of claims 1 to 9;- a turning table (101) rotatable around a wrapping axis (Y) and on which in use the load to be wrapped with said film (2) is arranged;- a gripper unit (103) fitted near a first side (108) of said turning table (101) and configured to grasp a portion of an initial strip of said film (2) when said first arm device (17) is in said transfer position (T) or when said second arm device (21) is in said respective transfer position so as to be able to start a wrapping cycle of wrapping said load by said film (2) coming from said first reel (9) or from said second reel (20).

11. Wrapping apparatus (100) according to claim 10, wherein said gripper unit (103) comprises a first claw element (104) and a second claw element (105) that are hinged between them, said gripper unit (103) being moveable between a closed gripping position (C) in which said first claw element (104) is near said second claw element (105) to clamp said portion of said initial strip of said film (2) therebetween and an open releasing position (A) in which said first claw element (104) is spaced away from said second claw element(105) and said film (5) can be released from said gripper unit (103).

12. Wrapping apparatus (100) according to claim 10 or 11, and further comprising a cutting / welding / grasping unit (109) comprising a cutting unit configured to cut said film, a welding unit configured to weld said film to a wrapping turn of said film around said load, and a further gripper unit configured to grasp during said wrapping cycle a strip of said film intended to wrap a subsequent load, said cutting / welding / grasping unit (109) being fitted near a second side (110) of said turning table (101) opposite said first side (108).

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