Background of the invention

[0001] The present invention relates to a cutting group and method for cutting a wrapping film, the cutting group being intended to be installed on a wrapping apparatus, in particular on an apparatus for wrapping objects like pallets or other machinery that requires sheet material to be cut by thermal action.

Prior art

[0002] A pallet is a substantially flat structure, usually made of wood, on which goods are placed so as to simplify the storage and transport thereof. Nevertheless, the “tower” of goods that is stacked on a pallet is not only devoid of protections but is often rather unstable. [0003] In order to resolve the problems mentioned above, a pallet wrapping machine is used nowadays that in particular wraps around the pallet and the goods an extendible film that has elasticity that is such as to be able to be applied and shaped around the goods and at the same time keep the goods in a stable position.

[0004] Different types of pallet wrapping machines exist that cater for the different manufacturing needs of a company. For this reason, wrapping machines of automatic type are normally inserted at the end of the production line and are connected directly to the machine that palletizes the product because they are not only able to wrap the load automatically but, at the end of the wrapping and independently, cut the last strip of film and then weld the strip.

[0005] In this type of wrapping machines, the cut is performed by a cutting group provided with a resting element, to tension and maintain in position the wrapping film, and with a cutting element.

[0006] In particular, traditional wrapping machines use an electrically heated resistance wire that by coming into direct contact with the wrapping film cuts the wrapping film along a set line.

[0007] An example of such a type of traditional wrapping machine provided with an electrically heated resistance wire is disclosed in EPl 142787 A2.

[0008] Nevertheless, the cutting technique disclosed above enables possible residue to be deposited on the wire and with the accumulation thereof reduces the cutting capacity of the wire, making it necessary to replace the wire.

[0009] Further, the direct contact between the incandescent wire and the wrapping film causes an odour to be emitted that is unpleasant for an operator assigned to the cutting operation.

[0010] Considering what has just been disclosed, it is clear that the drawbacks listed above do not relate only to the current pallet wrapping machines but more in general to all the wrapping apparatuses that cut the wrapping film using a type of thermal cutting with direct contact.

[0011] An improvement would therefore be desirable of current cutting groups for cutting wrapping film and thus of current apparatuses for wrapping or depositing films on objects, for example pallets, by a wrapping film; in particular it would be desirable to provide a solution that ensures great cutting capacity and constant operational effectiveness over time.

Ob jects of the invention

[0012] One object of the present invention is to improve current cutting groups for wrapping apparatuses.

[0013] Another object of the present invention is to provide a cutting group that is high- performing and provided with great cutting capacity and efficacy.

[0014] A further object of the present invention is to provide a cutting method and a cutting group that are able to maintain high cutting capacity and efficacy over time.

[0015] A further object of the present invention is to provide a technical solution that enables the operating life of a cutting group to be extended.

[0016] A further object of the present invention is to provide a technical solution for cutting film that is able to eliminate or at least significantly reduce the emission of unpleasant odour during the cutting operations.

Summary of the invention

[0017] The objects listed above and still other objects and advantages are achieved by a cutting group and a method for cutting according to what is defined in the attached claims.

Brief description of the drawings

[0018] The invention can be better understood with reference to the attached drawings that illustrate an embodiment thereof by means of non-limiting example in which:

Fig. 1 is a perspective view of a cutting group according to the invention;

Fig. 2 is a perspective view of the group of Fig.l on which a wrapping film to be cut is rested;

Fig.3 is a view from above of Fig.2;

Fig.4 is a perspective view of the group of Fig.1 installed on an apparatus for wrapping pallets that is coupled with a pallet.

Detailed description of the invention

[0019] The general features of the present invention will be illustrated below through the embodiment of the attached figures that is provided by way of non-limiting example.

[0020] With reference to the attached Figures, a cutting group 10 is disclosed below.

[0021] The cutting group 10 is intended to be installed on an apparatus A for wrapping, with a film F, objects, in particular on an apparatus A for wrapping pallets P, as is visible in Fig.4.

[0022] In particular, the apparatus A is configured to wrap a pallet P by means of an elastic wrapping film F.

[0023] The apparatus A comprises a base B that supports a movement group C arranged for supporting and moving the cutting group 10 with respect to the pallet P.

[0024] With reference to Figs 1,2, the cutting group 10 provides a thermally activatable cutting element 11 that is suitable for cutting cleanly and precisely a wrapping film F.

[0025] The cutting group 10 comprises a first resting element 12 for restingly receiving the film F. The first resting element 12 is placed in proximity to the cutting element 11.

[0026] The cutting group 10 further has a second resting element 13 for restingly receiving the film F in proximity to the cutting element 11.

[0027] In particular, the second resting element 13 is so arranged that the cutting element 11 is positioned between the first resting element 12 and the second resting element 13; the latter, as is visible in Fig.2, have respective external surface portions 14,15 which define a resting plane, inside which, during the cutting operation, the film F lies. The resting elements 12,13 can be, for example, idler rollers. According to further embodiments that are not shown, the resting elements 12,13 can include bars, rods or other desired elements.

[0028] The resting elements 12,13 are so arranged as to prevent the film F from coming into contact with the cutting element 11. In other words, the cutting group 10 according to the invention, ensures spacing between the film F and the cutting element 11.

[0029] With reference to Fig.l, the cutting element 11 has a longitudinal extension axis Y 1 that is parallel both to a longitudinal extension axis Y2 of the first resting element 12 and to a longitudinal extension axis Y3 of the second resting element 13. In this manner, the resting plane is parallel to the cutting element 11. The cutting element 11 can be, for example, a thermally activatable wire, tensioned by tensioning means 16,17.

[0030] Further, as is more visible in Fig.3, the cutting element 11 is placed at a distance d from the resting plane that is such as to enable the film F to be cut by thermal radiation once the thermally activatable cutting element 11 has been made incandescent. In this manner, the cut is made without direct contact between the cutting element 11 and the film F. Owing to this configuration, any residues are prevented from depositing on the cutting element 11 and, as they accumulate, reduce its cutting capacity.

[0031] As is visible in Fig.2, the extent of the cutting element 11 along the longitudinal extension axis Y1 is at least equal to the width L of the film along the direction of the axis Y1 so as to cut entirely the film F in a single cutting operation. In the same manner, also the longitudinal extent of the resting elements 12,13 along the respective longitudinal extension axes Y2, Y3 is at least equal to the width L of the film F along the direction of the axes Y2,Y3 such that the film F can rest on the resting elements 12,13 along the entire width thereof and by so doing lie inside the aforesaid resting plane.

[0032] Owing to the aforesaid features, the cutting group 10 not only has great cutting capacity and efficacy, but also ensures that this cutting capacity remains constant over time, thus also extending the working life of the cutting element 11. Further, by avoiding the contact between the film F and the thermally activatable cutting element 11, the emission of unpleasant smells is suppressed or at least drastically reduced during the cutting operation.

[0033] From what has been set out above, it is clear that the cutting group according to the invention successively achieves all the previously mentioned set objects.

[0034] What has been disclosed and shown in the attached drawings has been provided merely by way of illustrative example of the innovative features of the cutting group.

[0035] In practice, the materials, inasmuch as they are compatible with the specific use and with the respective individual components for which they are intended, can be chosen appropriately on the basis of the requested requirements and on the basis of the available prior art. Variations on and/or additions to what has been disclosed and illustrated in the attached drawings are possible.