Background of the invention

[0001] The present invention relates to a counteracting group for heat sealing wrapping films, intended to be installed on a wrapping apparatus, in particular on a wrapping apparatus for wrapping a pallet.

State of the art

[0002] There is known the use of pallets for storing and transporting goods.

[0003] Furthermore, also known is the use of pallet wrapping device for wrapping the pallet and the goods placed thereon using an extensible film so as to stabilise the entirety and make it easier to handle for transportation and/or storage.

[0004] In particular, the automatic wrapping devices are usually used in automated production lines and they are arranged at the end of the production line so as to automatically wrap the load, at the end of the wrapping, to cut the trailing edge of the film, that is the so-called tail of the film, so as to then seal or fix it to the underlying layer of the film applied to the load.

[0005] The sealing, or more precisely the heat sealing, of the trailing edge of the film may be carried out in direct contact with the wrapped load (in this case the heat-sealing elements included in the wrapping device may press directly into the load wrapped by the film), or by using a concealable counteracting bar which is positioned so as to be interposed between the last layer of the film applied to the load and one or more trailing turns of the film: in other words, the wrapped trailing turn rests on the counteracting bar. In this manner, the heat-sealing elements may press against a concealable counteracting bar interacting only with the layers of the film that have been wrapped even around the counteracting bar, that is only with the layers of film required for an effective sealing. The second option is particularly advantageous, for example, whenever the surface of the load is too uneven to allow a sealing in direct contact, or even in cases in which there arises the need to avoid any contact with the palletised product so as to ensure the wholeness of the load.

[0006] In particular, when present, the counteracting bar is equipped to a counteracting group which manages both the engagement and disengagement thereof; however, the current counteracting groups often have a complex mechanism which results in a large overall dimension, therefore affecting the effectiveness and comfort of use thereof.

[0007] Furthermore, the disengagement of the counteracting bar could be complex in the case where the shape and/or consistency of the load counters the removal thereof, therefore reducing the versatility of the pallet wrapping device.

[0008] Therefore, it would be desirable to improve the current counteracting groups for wrapping films and, therefore, also the current automatic pallet wrapping devices so as to ensure high versatility and, at the same time, small overall dimensions and a simple mechanism.

Objects and advantages of the invention

[0009] An object of the present invention is to provide a counteracting group which has high versatility.

[0010] A further object of the present invention is to provide a counteracting group which has small overall dimensions.

[0011] A further object of the present invention is to provide a counteracting group whose components can be moved according to a simplified mechanism.

[0012] An advantage of the present invention is to provide a counteracting group which can be easily disengaged from the load at the end of the heat-sealing operation.

Brief description of the invention

[0013] These objects and advantages are attained by a counteracting group as defined in the attached claims.

Brief description of the drawings

[0014] The invention shall be better understood with reference to the enclosed drawings which show an exemplifying and non-limiting embodiment, thereof, wherein:

Fig.l is a perspective view of a counteracting group according to the invention on which there is placed a wrapping film to be heat-sealed;

Fig.2 is a top view of the group of Fig.l, which shows a maximum projection position (double dashed line) and a maximum retraction position (solid line);

Fig.3 is a perspective view of the group of Fig.l, which shows an operative position (double dashed line) and a first inoperative position (solid line);

Fig.4 is a perspective view of the group of Fig.l, which shows the operative position of Fig.3 (double dashed line) and a second inoperative position (solid line);

Fig.5 is a lateral view of Fig.3;

Fig.6 is a lateral view showing the group of Fig.l installed on a pallet wrapping apparatus in a position subsequent to a concealable movement beneath a pallet;

Fig.7 is a perspective view of the group of Fig. l installed on a pallet wrapping apparatus coupled to a pallet;

Fig.8 is a top view of the group of Fig.1 installed on a pallet wrapping apparatus in the maximum retraction position;

Fig.9 is a partial lateral cross-sectional view of a portion of the group of Fig.1.

Detailed description of the invention

[0015] The general characteristics of the present invention will be shown below through the exemplifying and non-limiting embodiment of the attached figures.

[0016] With reference to the attached figures, there is shown a counteracting group 10 intended to be installed on an apparatus A for wrapping using a wrapping film F, in particular on an apparatus A for wrapping pallets P, as shown in Fig.7.

[0017] With reference to Fig.1, the counteracting group 10 provides for a bar-shaped counteracting element 14, suitable to restingly receive a portion of the film F, and a support unit 11 for the bar-shaped counteracting element 14; the latter, as shown in Figs.3 and 4, can be moved from an inoperative position Rl; R2 on the support unit 11 to an extended operative position O.

[0018] In particular, when the bar-shaped counteracting element 14 is in the extended operative position O, it projects transversely with respect to the support unit 11 to restingly receive the film F and allow a heat-sealing operation on the film F at the end of the wrapping of the pallet P; to this end, the bar-shaped counteracting element 14 has a recessed area 29 suitable to provide an even support surface for the heat-sealing elements (not shown) included in the apparatus A during the heat-sealing operation. Otherwise, at the end of the heat-sealing operation, the bar-shaped counteracting element 14 takes an inoperative position Rl; R2 so as to be disengaged from the film F.

[0019] As shown in Figs.4 and 9, the support unit 11 has a box-like housing 34 which extends longitudinally along the support unit 11, within which there is housed a rack 28 connected, through a gearwheel 35, to the bar-shaped counteracting element 14.

[0020] The rack 28 is movable along the box-like housing 34 due to second actuator means 36 so as to allow the movement of the bar-shaped counteracting element 14 from the folded position Rl; R2 to the extended operative position O.

[0021] The bar-shaped counteracting element 14, in particular, is removably connected to the gearwheel 35 so that it can vary its position with respect to the rack 28: for example, in a possible embodiment of the counteracting group 10, the bar-shaped counteracting element 14 may be fixed in a manner which it can be disassembled, in particular using screws, to a pivot integrally joined with the gearwheel 35.

[0022] The second actuator means may for example be selected from the group comprising: hydraulic actuator cylinders, pneumatic actuator cylinders and electric actuator cylinders.

[0023] As shown in Fig.2, the counteracting group 10 further comprises a support structure 25 for the support unit 11 and handling means 16, 17, 18 configured to move the support unit 11, with respect to the support structure 25, along a displacement direction DI; the displacement direction DI is substantially perpendicular to the longitudinal extension axis of the box-like unit 34.

[0024] Therefore, the movement of the support unit 11 allows to move the bar-shaped counteracting element 14 from a maximum projection position MP towards the pallet P to a maximum retraction position MR with respect to the pallet P.

[0025] In detail, as shown in Fig.1, the handling means 16, 17, 18 comprises lever means 17, 18, mutually hinged and having a movable end 30 hinged to the support unit 11 and a stationary end 31 hinged to the support structure 25, and first actuator means 16 arranged to actuate the lever means 17, 18 and connected, at a first end 32, to the support structure 25 and, at a second end 33, to the lever means 17, 18.

[0026] As shown in Fig.2, the first actuator means 16 is configured to exert a push and pull action on the lever means 17, 18 along an operative direction D2 arranged transversely with respect to the displacement direction DI.

[0027] The first actuator means may for example be selected from the group comprising: hydraulic actuator cylinders, pneumatic actuator cylinders and electric actuator cylinders.

[0028] In a possible embodiment of the counteracting group 10, as shown in Figs.1 and 5, the lever means 17, 18 comprises a first lever 17 and a second lever 18 which are mutually hinged using first pivot means 22.

[0029] Furthermore, the first lever 17 is also hinged to the support unit 11 through second pivot means 26 at the movable end 30, while the second lever 18 is hinged both to the support structure 25 through pivot means 20 at the stationary end 31 and to the first actuator means 16 through fourth pivot means 21 at the second end 33. The fourth pivot means 21 is positioned closer to the third pivot means 20 with respect to the first pivot means 22. In addition, the first actuator means 16 is also hinged to the support structure 25 through fifth pivot means 27 at the first end 32. [0030] With reference to Figs.1-4, the displacement of the support unit 11 along the displacement direction DI to approach/move away the bar-shaped counteracting element 14 to/from the pallet P, that is move the support unit 11 along direction DI from the maximum projection position MP to the maximum retraction position MR, is guided by track means 15 suitable to slide within slider means 24 arranged on the support structure 25.

[0031] Furthermore, the track means 15 has stop means 23 for stopping the sliding of the track means 15 within the slider means 24 once the support unit 11 has reached the maximum projection position MP.

[0032] Therefore, the support unit 11 can be slidably and safely moved along the direction DI from the maximum projection position MP to the maximum retraction position MR.

[0033] With reference to Fig.2, the lever means 17, 18 and the first actuator means 16 extend and can be moved substantially parallel to the same horizontal plane and they are oriented so as to reduce the overall dimensions as much as possible in the direction parallel to the direction DI, as shown in Fig.8.

[0034] Lastly, as shown in Fig.5, the counteracting group 10 has third actuator means 12,13 connected to the support structure 25 so as to allow a movement of the support structure 25, and therefore of the support unit 11, along a direction D3 perpendicular to the horizontal plane and therefore to direction DI, so as to allow a concealable movement of the support unit 11 beneath the pallet P (see Fig.6). In other words, the vertical height of the counteracting group 10 can be changed through the aforementioned third actuator means 12,13.

[0035] The third actuator means 12, 13 may for example be two, and selected from the group comprising: hydraulic actuator cylinders, pneumatic actuator cylinders, electric actuator cylinders.

[0036] The first actuator means 16 and the third actuator means 12, 13 allow the support unit 11 to move along the direction DI and/or along the direction D3 separately, that is without a displacement along one direction (DI or D3) necessarily entailing a displacement along the other direction (D3 or DI) too. Therefore, this allows to avoid using the first actuator means 16 or the third actuator means 12, 13 unnecessarily. Due to this configuration, the counteracting group 10 can be moved linearly independently both in the vertical direction and in the horizontal direction. The full independence between the actuation along a vertical linear trajectory and the actuation along a horizontal linear trajectory results in an operative versatility and it allows significant comfort in reaching the desired position with respect to the pallet P without having to subject the counteracting group 10 to unnecessary displacement components.

[0037] Below is more detailed description of the movement of the bar-shaped counteracting element 14 from the folded position Rl; R2 to the extended operative position O.

[0038] As mentioned above, the bar-shaped counteracting element 14 is removably connected to the gearwheel 35 so that it can change its position with respect to the rack 28: for example, with reference to Figs.3 and 4, the bar-shaped counteracting element 14 is configured to rotate - around an axis Al parallel to the direction DI - from the extended operative position O to the inoperative position Rl; R2 in a first rotation direction rl or in a second rotation direction r2.

[0039] In other words, the bar-shaped counteracting element 14 is configured to move towards a folded inoperative position Rl on the support unit 11, or towards an unfolded inoperative position R2 in which the bar-shaped counteracting element 14 extends like an extension of the support unit 11.

[0040] In particular, the rotation of the bar-shaped counteracting element 14 is caused by the linear movement, induced by the second actuator means 36, of the rack 28 which results in a rotation of the gearwheel 35 and, lastly, in a rotation of the bar-shaped counteracting element 14.

[0041] The option of being able to configure the bar-shaped counteracting element 14 so as to rotate in the first direction rl, or in the second direction r2, allows the bar-shaped counteracting element 14 to always move in a direction substantially matching an advancement direction of the pallet P at the end of the heat-sealing operation, therefore facilitating the disengagement of the bar-shaped counteracting element 14 from the film F. [0042] In the light of the above, it is clear that the counteracting group 10 according to the invention successfully attains all the pre-established objects mentioned above.

[0043] The content subject-matter of the description and shown in the attached drawings, has been provided by way of showing the innovative characteristics of the counteracting group 10.

[0044] Basically, the materials, to the extent which they are compatible with the specific use and with the respective individual components they are designed for, may be suitably selected as a function of the required requirements of the current state of the art. The above, as disclosed and illustrated in the attached drawings, may be subjected to variants and/or additions.