Sofa packaging machine

Abstract

A sofa packaging machine (100), comprising a conveyor (20) configured to receive a sofa and to convey it; a packaging station (30) configured to receive the sofa and proceed to package it with a flexible film, and an unloading station (40) configured to receive the packaged sofa and convey it towards a collection section (31). Wherein the packaging station (30) comprises a first and a second sealing bar (30a, 30b) respectively mounted on a first and a second carriage (31a, 31b) independent from each other and slidably movable. And wherein said conveyor (20) is interposed between said first and second sealing bars (30a, 30b) so that the sofa, during use, is conveyed through said sealing bars (30a, 30b). And wherein said first and second carriages (31a, 31b) are movable reciprocally nearer and / or farther away, between a rest configuration and a closed configuration, so as to seal the edges of the film in order to produce a closed, sealed packaging around the sofa.

Description

[0001] “SOFA PACKAGING MACHINE”

[0002] * * * * *

[0003] TECHNICAL FIELD

[0004] The present invention relates to a sofa packaging machine.

[0005] In greater detail, the machine according to the invention fits into the technical sector of the manufacture and sale of automatic machines, apparatus and more in general systems for packaging and / or packing products of varying nature, in particular of a non-food type, such as, for example, products intended for the textile and decorating sector (e.g. cushions, sofas, and furniture of varying nature), as well as into the industrial sector.

[0006] More specifically, the machine according to the invention has particular technical application in the sofa packaging and / or packing sector.

[0007] PRIOR ART

[0008] In the aforesaid reference technical sector, the use of machines for packaging products such as the ones briefly mentioned above is well known.

[0009] As illustrated in figures 1 A-1 D, in the specific case of packaging a sofa, a machine of the known type typically comprises a feed conveyor configured to receive a sofa in an infeed section thereof (for example manually by an operator or in an automated manner by means of an anthropomorphic manipulator or the like) and convey it along a work direction.

[0010] The machine of the known type further comprises a packaging station operatively connected to the feed conveyor and configured to receive the moving sofa coming from the conveyor, bag it and / or pack it with a flexible packaging film around it, so as to create an at least partially closed wrapping.

[0011] More specifically, the packaging station comprises a sealing unit having a closed structure and shaped so as to embrace the conveyor (and thusthe sofa to be packaged). In other words, the sealing unit has a portaltype shape.

[0012] For the purpose of producing a packaging for the sofa, the sealing unit comprises a pair of sealing bars slidably movable nearer and / or farther away from each other and configured to abut each other so as to seal edges of the flexible film.

[0013] The machine of the known type further comprises a retractable or fixed conveyor, interposed between the feed conveyor and the sealing unit, and movable along a direction opposite the direction of advancement of the sofa during the packaging operation. In other words, the retractable conveyor carries out a gradual retracting movement as the sofa advances along the working direction and passes through the sealing unit, becoming enveloped in the packaging film. In this manner, the retractable conveyor generates an access opening that extends transversely to the direction of advancement of the sofa, to enable the aforesaid pair of sealing bars to enter into said opening and abut in reciprocal contact to seal the edges of the film and thus produce a sealed wrapping around the sofa.

[0014] In other words, the retractable conveyor allows a volume to be generated which is occupied by the sealing bars at every operating cycle of the machine, i.e. every time a sofa is packaged.

[0015] The machine of the known type further comprises an unloading conveyor operatively connected to the packaging station and configured to receive the packaged sofa and convey it towards a collection section. The machine of the known type further comprises a plurality of safety and / or protection barriers connected to one another and arranged in position around the packaging station, and in particular the sealing unit comprising the movable sealing bars, and at least partially around the feed and unloading conveyor, so as to create a protective wall for an operator located in the vicinity.In greater detail, the safety and / or protection barriers at least partially shield the machine, thus preventing any close contact between an operator and the machine itself.

[0016] The sofa packaging machine of the known type briefly described thus far has revealed in practice not to be free of drawbacks.

[0017] In particular, the main drawback lies in the fact that the machine of the known type is cumbersome, i.e. voluminous and / or not very compact. A further drawback lies in the fact that the machine of the known type is complex in construction and costly. In fact, such a machine requires a large number of mechanical / mechatronic components and members in order for it to work correctly. In other words, the machine of the known type involves a plurality of functional groups cooperating with one another, each equipped with multiple members and components, which increase the constructive and operating complexity of the machine as a whole.

[0018] A further drawback lies in the fact that the machine of the known type is not easy for a user / operator to use. In fact, the presence of a plurality of safety and / or protection barriers hinders the operations of a user, making the activities of controlling, monitoring and maintaining the machine carried out by the operator himself difficult.

[0019] A further drawback lies in the fact that the machine of the known type has a packaging / operating speed that is slow, or at least unsatisfactory. In fact, as briefly described above, the machine of the known type requires at least one retractable conveyor that has a movement of the retracting type in order to create an access opening occupiable by the sealing bars for the purpose of sealing the film around a sofa. This operation makes every operating cycle of the known machine long, with a consequent unsatisfactory overall efficiency of the machine.

[0020] A further drawback lies in the fact that the machine of the known type requires considerable amounts of energy for its correct operation. In greater detail, the known machine, and in particular the sealing bars ofthe sealing unit, require large flow rates (cubic metres per hour) of compressed air, with a consequent strong impact in terms of the machine’s energy consumption.

[0021] OBJECTS OF THE INVENTION

[0022] One object of the present invention is to provide a sofa packaging machine which enables the drawbacks of the above-mentioned prior art to be obviated.

[0023] A further object of the present invention is to provide a sofa packaging machine that is compact and / or occupies little space, i.e. which has a structural and / or functional configuration which is streamlined and simplified compared to a machine of the known type.

[0024] A further object of the present invention is to provide a sofa packaging machine that is simple and economical.

[0025] A further object of the present invention is to provide a sofa packaging machine that can be easily accessed and monitored by an operator during its operation.

[0026] A further object of the present invention is to provide a sofa packaging machine that is wholly safe and reliable.

[0027] A further object of the present invention is to provide a sofa packaging machine that has a satisfactory overall efficiency (understood as the number of products packaged per unit of time), or at least one that is superior to that of a machine of the prior art.

[0028] A further object of the present invention is to provide a sofa packaging machine that requires a low amount of energy in order to work correctly, or at least less than is required for a machine of the prior art. In other words, to provide a machine that has low energy consumption and, consequently, an impact that is limited in economic terms, and lower than that of a machine of the known type.

[0029] A further object of the present invention is to provide a sofa packaging machine that has an alternative and / or improved configuration, both instructural terms and in functional terms, compared to a machine of the prior art.

[0030] SUMMARY

[0031] All the objects, both individually and in any combination thereof, and others that will emerge from the detailed description that follows are achieved, according to the invention, with a sofa packaging machine having the features specified in the independent claim 1.

[0032] The dependent claims outline particularly advantageous embodiments of the invention.

[0033] BRIEF DESCRIPTION OF THE DRAWINGS Additional features and advantages of the present invention will emerge more clearly from the approximate and thus non-limiting description of a preferred but not exclusive embodiment of a sofa packaging machine, as illustrated in the appended drawings, in which:

[0034] - figures 1A-1D show a sofa packaging machine according to the prior art;

[0035] - figure 2 shows, according to a perspective view, a sofa packaging machine according to one embodiment of the invention;

[0036] - figure 3 shows, according to a perspective view, the machine illustrated in figure 2 with some parts removed to better highlight others;

[0037] - figure 4 shows, according to a longitudinal sectional view, the machine illustrated in figure 3;

[0038] - figure 5 shows, according to a perspective view, a portion of the machine illustrated in figure 2 with some parts removed to better highlight others.

[0039] With reference to the drawings, they serve solely to illustrate embodiments of the invention with the aim of better clarifying, in combination with the description, the inventive principles at the basis of the invention.

[0040] DETAILED DESCRIPTION OF THE INVENTIONWith reference to the appended figures, a sofa packaging machine according to the present invention is denoted in its entirety by the number 100.

[0041] In the description that follows, specific reference will be made to a machine for packaging and / or packing sofas. However, the machine according to the invention may also be used to package products of another nature (for example furniture of various types or products belonging to the textile, decorating or industrial sectors), without going outside the scope of protection.

[0042] In the description that follows, reference will be made to the terms “packaging” and “packing” indistinctly, that is, to indicate an operation, substantially automatic, of wrapping a flexible packaging film, in particular made of a polymeric material (e.g. polyethylene PE, polypropylene PP and still others), around an outer profile of a sofa, so as to create a closed wrapping sealed around the sofa itself.

[0043] In accordance with the embodiment of the invention illustrated in the appended figures 2-5, a sofa packaging machine 100 comprises a conveyor 20 extending along a first axis Y-Y, arranged substantially parallel to the ground (i.e. horizontal).

[0044] The conveyor 20 is configured to receive a sofa in an infeed section 21 thereof, arranged at a first end 21a thereof, and to convey it along the first axis Y-Y on a conveyance surface 22 thereof.

[0045] Preferably, the conveyor 20 is of the belt conveyor type and the conveyance surface 22 preferably comprises a moving belt, substantially planar and configured to convey a sofa to be packaged, so as to cause it to advance along the first axis Y-Y.

[0046] Preferably, the machine 100 comprises centring means (not illustrated in the appended figures) arranged laterally to the conveyor 20 and configured to centre the sofa relative to the first axis Y-Y, and to align a pair of its sides parallel to the first axis Y-Y itself.The machine 100 further comprises a packaging station 30 mounted in a position along the extent of the conveyor 20, configured to receive the sofa and proceed to package it with a flexible film.

[0047] More specifically, the packaging station 30 comprises a first reel 35 and a second reel (not illustrated in the appended figures), each arranged oriented with an axis thereof orthogonal to the first axis Y-Y (i.e. vertically), and each configured to feed the machine 100 with a flexible packaging film (e.g. a film made of polymeric material).

[0048] In greater detail, the packaging station 30 is configured to unwind the film from the first reel 35 and from the second reel and to join together the edges of each film unwound from the reels in a substantially central position of the conveyor 20. In this manner, a film barrier is created against the sofa advancing on the conveyor 20 itself. In other words, the film wound on each reel is unwound and conveyed towards the middle of the conveyor 20 (i.e. towards the first axis Y-Y) in order to be reciprocally connected / joined, thereby creating a single film, i.e. a film barrier. The film barrier defines a substantially vertical surface adapted to be intercepted (in particular pushed into) by the advancing sofa. In other words, packaging of the sofa takes place by virtue of an interception of the aforesaid film barrier by the sofa itself. The advancement of the sofa along the first axis Y-Y produces an envelopment, and thus a substantial wrapping of the film around the sofa, thus creating a sort of at least partially closed package.

[0049] According to one aspect of the invention, the packaging station 30 is further configured to seal edges of the film in order to create a sealed wrapping around the sofa to be packaged.

[0050] The machine 100 further comprises an unloading station 40 connected to the packaging station 30, configured to receive the packaged sofa and convey it towards a collection section 31 , preferably arranged at a second end 21b thereof and opposite the infeed section 21 (and thus the first end 21a).Preferably, the unloading station 40 comprises a conveyor belt wholly similar to that of the conveyor 20 described previously.

[0051] In accordance with the embodiment of the invention illustrated in detail in figure 2, the packaging station 30 comprises a first and a second sealing bar 30a, 30b respectively mounted on a first and a second carriage 31 a, 31b independent from each other and slidably movable along a second axis Z-Z, transverse to first axis Y-Y, preferably orthogonal.

[0052] As illustrated in the appended figures, the first and second carriages 31 a, 31 b are arranged facing each other and are positioned in respective lateral edge portions of the conveyor 20.

[0053] In fact, the conveyor 20 is interposed between the first and second sealing bars 30a, 30b so that the sofa, during use, is conveyed through the sealing bars 30a, 30b.

[0054] In other words, the sealing bars 30a, 30b are arranged laterally to the conveyor 20 and close like a clamp around the conveyor 20 itself, and thus around the sofa packaging film.

[0055] According to one aspect of the invention, the first and second carriages 31 a, 31b are movable reciprocally nearer and / or farther away, between a rest configuration, in which said sealing bars 30a, 30b are distal, and a closed configuration, in which said sealing bars 30a, 30b are substantially abutting so as to seal the edges of the film in order to produce a closed, sealed packaging around the sofa.

[0056] Advantageously, the machine 100 is simplified in its structural architecture, since it does not require complex, cumbersome support frames or structures on which to mount the sealing bars. The result is a simple and compact structure.

[0057] In addition, the machine 100 has sealing carriages independent from each other and individually activatable, thus advantageously increasing the operating flexibility of the machine itself.According to one aspect of the invention, in particular illustrated in figure 2, the first and second sealing bars 30a, 30b are mounted on the first and second carriages 31 a, 31b, and the latter comprise respective support structures 300 having an open profile so as not to surround the sealing bars 30a, 30b themselves from above.

[0058] As may be seen from figure 3, the aforesaid respective support structures 300 are, at least in part, “C”-shaped according to a cross section along a vertical plane, so as to be able to embrace the conveyor 20 in the neared position.

[0059] Advantageously, the machine 100 is simplified in its structural architecture as it does not require movable, in particular retractable, devices adapted to create a volume of space for the carriages and thus the respective sealing bars. The result is a streamlined machine 100 which is constructively simpler than one of the prior art (cf. figures 1A-1 D).

[0060] The C-shaped support structures 300 each have an upper portion configured to receive a sealing bar 30a, 30b, a lower leg and an intermediate connection portion between the upper portion and the lower leg.

[0061] In greater detail, the lower leg is slidably constrained to slide guides (introduced and described in greater detail below in the description) so as to enable a sliding movement of each carriage.

[0062] As illustrated in figure 4, each sealing bar 30a, 30b is distanced below, according to a direction orthogonal to the conveyer 20, from the lower leg of the C-shaped support structure 300, by a predefined distance so as to be able to accommodate, at least partially, the conveyor 20 in the neared position (i.e. closed configuration).

[0063] In other words, the predefined distance extends along a third axis W-W (described below) orthogonal to the surface of the conveyor 20, and enables each carriage to embrace, at least partially, the thickness of the conveyor by insertion therein.In still other words, each C-shaped support structure 300 defines a housing seat open at the side and adapted to at least partially receive the conveyor 20 when the respective carriage is arranged in the neared position, thus allowing the sealing bars 30a, 30b to be arranged in proximity to the surface of the conveyor 20 without interfering with the latter.

[0064] This configuration allows the sealing bars 30a, 30b to be kept suspended relative to the conveyor 20, while at the same time ensuring a correct distribution of the loads and a high structural stability during the sealing operating steps. The intermediate connection portion thus performs both a structural function and a distancing one, by ensuring that the aforesaid predefined distance is maintained along the third axis W-W. Advantageously, the C shape of the support structures 300 allows an easy installation and removal of the carriages with respect to the conveyor 20, as well as easy inspection and maintenance of the sealing bars 30a, 30b and of the associated components.

[0065] In addition, this geometry makes it possible to reduce the overall dimensions of the sealing unit, thus improving accessibility and the integration thereof into the sofa packaging machine 100.

[0066] Preferably, the aforesaid support structures 300 are each made of metal material (e.g. steel), and in particular sheet metal, to impart robustness and stiffness to the first and second carriages 31 a, 31b during their operation.

[0067] Preferably, the aforesaid support structures 300 are wholly similar and symmetrical to each other; as a result, the first and second carriages 31 a, 31b are substantially similar to each other.

[0068] As illustrated in figure 3, the first and second sealing bars 30a, 30b are mounted on the first and second carriages 31 a, 31b respectively in a raised position relative to the conveyance surface 22 of the conveyor 20, so as to define a distance D relative to the conveyance surface 22 itself.More specifically, the distance D is such as to allow a movement of the first and second sealing bars 30a, 30b from the rest configuration to the closed configuration without interfering with the conveyor 20.

[0069] In other words, the distance D is a distance that extends substantially vertically, and thus orthogonally to the first axis Y-Y, and is measured starting from the respective bottom ends of each sealing bar towards the conveyance surface 20.

[0070] The distance D advantageously makes it possible to define a volume of space occupiable by each carriage 31 a, 31 b during a movement thereof transverse to the first axis Y-Y, without intercepting the conveyor 20 and, therefore, the conveyance surface 22 thereof.

[0071] Advantageously, the machine 100 does not require any retractable conveyor or auxiliary mobile device (as previously described in the prior art) configured to retract or at least move outside the volume occupied by each sealing bar 30a, 30b during a movement thereof between the aforesaid rest configuration and the closed configuration.

[0072] In accordance with the embodiment illustrated in figures 2-3, the packaging station 30 comprises a base 310 on which drive means 50 are mounted.

[0073] The base 50 extends along the second axis Z-Z, and is preferably made in one piece, in particular in common with the first and second carriages 31a, 31b.

[0074] In greater detail, as illustrated in figure 2, the base 310 is arranged in a lowered position relative to the conveyor 20, so as pass across it transversely and connect the first and second carriages 31 a, 31 b to each other.

[0075] Preferably, the base 310 has a housing volume such as to define an internally hollow structure, for example wholly similar to a box, and configured to house components of varying nature and mechanical and mechatronic members, including in particular the drive means 50.In particular, the drive means 50 are connected respectively to the first and second carriages 31 a, 31b and are configured to drive them along the second axis Z-Z between the rest and closed configurations.

[0076] In greater detail, the drive means 50 are mounted on the base 310 and arranged in the housing volume in such a way as not to protrude beyond the dimension defined by the base 310 itself.

[0077] According to one aspect of the invention, the packaging station 30 comprises a first and a second slide guide 32,33 mounted on the base 310 and arranged aligned and parallel to each other along the second axis Z-Z.

[0078] As illustrated in figure 3, the aforesaid slide guides 32, 33 are arranged in such a way as to create a pair of slide guides, preferably extending substantially along the entire extent of the base 310.

[0079] The first and second slide guides 32,33 are configured to be slidably coupled with the first and second carriages 31 a, 31b so as to enable a movement of the aforesaid carriages 31 a, 31b.

[0080] In other words, the first and second slide guides 32,33 define respective sliding tracks for the carriages 31 a, 31b, and define a coupling of the sliding prismatic type with the carriages 31 a, 31b themselves. In fact, each carriage 31 a, 31b comprises a plurality of sliding shoes 37 configured to couple with the first and second slide guides 32, 33 so as to define the aforesaid prismatic coupling.

[0081] Preferably, the first and second slide guides 32, 33 can be made in sections, for example two sections each as illustrated in figure 3.

[0082] According to one aspect of the invention, the drive means 50 comprise an electric motor 51 , preferably of the asynchronous or brushless type, preferably mounted in the housing volume of the base 310; and a screw mechanism extending along the second axis Z-Z and connected to the electric motor 51 in order to be driven.Preferably, the drive means 50 comprise a coupling 53 configured to connect the electric motor 51 and the screw mechanism, in order to draw it in rotation about an axis thereof.

[0083] According to one aspect of the invention, the screw mechanism comprises a threaded bar 52’, configured to rotate about an axis thereof (parallel to the second axis Z-Z), and a nut 52” slidably mounted on the threaded bar 52’ and configured to translate along the threaded bar 52’ during a rotation of the threaded bar 52’ itself.

[0084] More specifically, the nut 52” is mechanically connected to (i.e. is integral with) each of the first and second carriages 31 a, 31b, respectively, to enable a movement thereof along the first and second slide guides 32,33.

[0085] In other words, the screw mechanism just briefly described, transforms a rotational motion of the electric motor 51 applied on the threaded bar 52’ into a translational motion of the nut 52” and, consequently, of the first and second carriages 31 a, 31b to which it is connected.

[0086] According to one aspect of the invention, the screw mechanism is preferably of the recirculating ball type.

[0087] In other words, the threaded bar 52’ and the nut 52” are preferably of the recirculating ball type.

[0088] According to a further aspect of the invention (not illustrated) the screw mechanism is preferably of the trapezoidal screw type.

[0089] According to a further aspect of the invention (not illustrated), the movement of the first and second carriages 31 a, 31b may preferably be achieved by means of a belt-pulley mechanism, preferably of the toothed type. This movement mechanism is well known to the person skilled in the art and thus not further described.

[0090] According to one aspect of the invention, at least one of the first and second sealing bars 30a, 30b comprises at least one force transducer, configured to measure a force applied by the at least one of the first and second sealing bars 30a, 30b on the film during packaging of a sofa.Advantageously, the presence of the at least one force transducer enables the measurement of a force applied on at least one sealing bar 30a, 30b.

[0091] In particular, according to one aspect of the invention, at least one of the first and second sealing bars 30a, 30b comprises at least one pair of force transducers 70a, 70b connected to each other and cooperating to measure a force applied by the at least one of the first and second sealing bars 30a, 30b (in particular by means of one or more pneumatic cylinders 90, as better described in detail below) on the film during packaging of a sofa.

[0092] In accordance with the embodiment of the invention, at least one of the first and second sealing bars 30a, 30b comprises a first and a second pair of force transducers 70a, 70b mounted on at least one sealing bar 30a, 30b in a position opposite each other.

[0093] Advantageously, the presence of the first and second pairs of force transducers 70a, 70b enables the measurement of a force applied by means of the sealing bars 30a, 30b on edges of film interposed between the sealing bars 30a, 30b themselves, or a body interposed between them.

[0094] Advantageously, the force transducers of each pair of force transducers 70a, 70b cooperate with each other so that if one of them should fail or start providing incorrect data it would ensure that the machine 100 can detect the problem and stop safely. What has just been briefly described is commonly called a “redundant connection” in the technical jargon of the sector, well known to the person skilled in the art and thus not further described.

[0095] In addition, by using a first and a second pair of force transducers 70a, 70b it is advantageously possible to compare the data acquired by each transducer and carry out a cross-check in order to monitor and signal any operating faults of the machine 100.Finally, the use of a first and a second pair of force transducers 70a, 70b allows for improving the measurement of a force applied in a generic point of at least one sealing bar and thus a better measurement of a distribution of the load applied on the sealing bars themselves.

[0096] In fact, irrespective of the point in which a force is applied along the extent of each sealing bar, the corresponding load detected by each pair of force transducers is analogous. The result is, advantageously, an improved precision of the measurement of the aforesaid load, and therefore a reduction in the risk of errors due to the application of external forces not uniformly distributed on the sealing bars themselves. In other words, mounting a first and a second pair of force transducers 70a, 70b on each sealing bar represents a system for continuously monitoring the operation of the machine 100, thereby enabling the latter to operate reliably and safely.

[0097] As illustrated in figure 5, the first and second pairs of force transducers are positioned in end portions of each sealing bar 30a, 30b.

[0098] In other words, as illustrated in figure 5, each pair of force transducers 70a, 70b is mounted along the vertical extent of at least one sealing bar 30a, 30b, one above the other.

[0099] Preferably, each force transducer is a load cell.

[0100] According to one aspect of the invention, the packaging station 30 comprises at least one position sensor (not illustrated in the appended figures), configured to detect a distance (different from the abovementioned distance D) of at least one of the first and second carriages 31 a, 31b along the second axis Z-Z relative to a respective predefined reference position of each carriage 31 a, 31b.

[0101] Preferably, the at least one position sensor is a potentiometer, and preferably mounted in the housing volume of the base 310, and in particular connected to the drive means 50.

[0102] According to one aspect of the invention, the packaging station 30 preferably comprises a pair of position sensors, connected to at leastone carriage 31 a, 31 b and cooperating with each other. In particular, the paired connection of each position sensor is of the redundant type, as previously described for each pair of force transducers 70a, 70b.

[0103] Preferably, each carriage 31a, 31b respectively comprises a pair of the aforesaid position sensors.

[0104] Advantageously, the movement of each carriage 31 a, 31b is constantly controlled and / or monitored by the at least one pair of position sensors, thereby contributing to making the machine 100 safe and reliable during its operation.

[0105] In fact, if the at least one pair of position sensors detects distance values differing from predefined parameters, each carriage 31 a, 31b and thus the respective sealing bars 30a, 30b will be blocked substantially instantly.

[0106] According to one aspect of the invention, at least one of the first and second sealing bars 30a, 30b comprises a pneumatic cylinder 90 configured to pressurise each of the sealing bars 30a, 30b when they are abutted against each other in the closed configuration, in order to press edges of film between them and seal them.

[0107] In greater detail, the pneumatic cylinder 90 has a stroke preferably comprised between 2 and 10 millimetres, preferably between 3 and 6 millimetres.

[0108] According to the embodiment illustrated in detail in figure 5, the at least one sealing bar 30a, 30b preferably comprises three pneumatic cylinders 90, substantially equal to each other, and mounted aligned with each other along the extent of the at least one sealing bar 30a, 30b. Preferably, the aforesaid pneumatic cylinders 90 are configured to generate a load acting between the sealing bars 30a, 30b comprised between about 100 and 300 kilograms, preferably comprised between 150 and 250 kilograms.

[0109] Advantageously, the machine 100 does not require large pneumatic cylinders having extended strokes (e.g. in the order of hundreds ofmillimetres) in order to seal and cut the sealed film edges. The result is a low energy consumption of compressed air required for the operation of sealing and cutting the film edges, which thus translates into savings in economic terms. In addition, the machine 100 and in particular the sealing unit 30 is compact and occupies little space, since the aforesaid pneumatic cylinders 90 and each pair of force transducers 70a, 70b are mounted on a respective support structure 310 of the first and second carriages 31 a, 31b, without going outside the space occupied by the latter.

[0110] According to one aspect of the invention, the machine 100 further comprises at least one control unit (not illustrated in the appended figures).

[0111] In greater detail, the control unit comprises at least one data receiving module, at least one module for processing the received data, and at least one module for sending the processed data.

[0112] According to one aspect of the invention, the control unit is connected to the first and second pairs of force transducers 70a, 70b, to the drive means 50 and to the pair of position sensors. In particular, the drive means 50 move the first and second carriages 31a, 31b, which carry the first and second sealing bars 30a, 30b mounted thereupon.

[0113] In this manner, when the first and second pairs of force transducers 70a, 70b measure a value of force (applied by the pneumatic cylinders 90) between the sealing bars 30a, 30b which exceeds a predefined / pre-established value, the control unit will block / stop the drive means 50 and thus the movement of the first and second carriages 31a, 31b, as well as of the sealing bars 30a, 30b.

[0114] Advantageously, the machine 100 is safe and reliable during its operation and thus does not require complex, costly and cumbersome safety barriers arranged as a covering around the machine 100 itself. In accordance with the embodiment of the invention illustrated in the appended figures, the packaging station 30 comprises a cutting means(not illustrated in the appended figures) slidably mounted on at least one of the sealing bars 30a, 30b and configured to cut film edges previously sealed together.

[0115] In greater detail, the cutting means is vertically movable along a third axis W-W, which is orthogonal to the first and second axes Y-Y, Z-Z, and configured to be activated when the sofa is wrapped by the film, i.e. when the sealing bars 30a, 30b are substantially abutted against each other in the closed configuration.

[0116] Preferably, the cutting means comprises a rodless linear cylinder and a cutting blade slidably connected to the linear cylinder itself. More specifically, the cutting blade slides vertically along the third axis W-W and cuts the film previously sealed to produce a closed wrapping.

[0117] Preferably, at least one sealing bar, preferably both, is profiled along the extent thereof so as to have a slot or groove along which the cutting means, and in particular the cutting blade, is free to slide. In this manner, the cutting blade is slidable along at least one sealing bar, without being an obstacle to a film sealing operation thereof.

Claims

C L A I M S1. A sofa packaging machine (100), comprising:- a conveyor (20) extending along a first axis (Y-Y), configured to receive a sofa in an infeed section (21) thereof and to convey it along said first axis (Y-Y) on a conveyance surface (22) thereof; - a packaging station (30) mounted along said conveyor (20), configured to receive the sofa and proceed to package it with a flexible film and seal edges of the film in order to create a sealed wrapping around the sofa itself;- an unloading station (40) connected to said packaging station (30), configured to receive the packaged sofa and convey it towards a collection section (31);characterised in that said packaging station (30) comprises a first and a second sealing bar (30a, 30b) respectively mounted on a first and a second carriage (31 a, 31b), independent from each other and slidably movable along a second axis (Z-Z), transverse to said first axis (Y-Y), and arranged facing each other;wherein said conveyor (20) is interposed between said first and second sealing bars (30a, 30b) so that the sofa, during use, is conveyed through said sealing bars (30a, 30b);and wherein said first and second carriages (31 a, 31b) are movable reciprocally nearer and / or farther away, between a rest configuration, in which said sealing bars (30a, 30b) are distal, and a closed configuration, in which said sealing bars (30a, 30b) are substantially abutting so as to seal the edges of the film in order to produce a closed, sealed packaging around the sofa;and wherein said first and second carriages (31 a, 31b) comprise respective support structures (300) having an open profile so as not to surround the sealing bars themselves from above;said respective support structures (300) being, at least in part, “C”-shaped according to a cross section along a vertical plane, so as to be able to embrace the conveyor in said neared position.

2. The machine (100) according to claim 1, wherein each sealing bar (30a, 30b) is distanced below, according to a direction orthogonal to the conveyer (20), from a lower leg of the C-shaped support structure (300), by a predefined distance so as to be able to accommodate, at least partially, said conveyor in said neared position.

3. The machine (100) according to any one of the preceding claims, wherein said first and second sealing bars (30a, 30b) are mounted on said first and second carriages (31 a, 31b) respectively in a raised position relative to said conveyance surface (22), so as to define a distance (D) relative to said conveyance surface (22), and such as to allow a movement of said first and second sealing bars (30a, 30b) from the rest configuration to the closed configuration without interfering with said conveyor (20).

4. The machine (100) according to any one of the preceding claims, wherein said packaging station (30) comprises a base (310) on which drive means (50) are mounted;said drive means (50) being connected, respectively, to said first and second carriages (31 a, 31b) and configured to drive them along said second axis (Z-Z) between said rest and closed configurations.

5. The machine (100) according to claim 4, wherein said packaging station (30) comprises a first and a second slide guide (32,33) mounted on said base (310) and arranged aligned and parallel to each other along said second axis (Z-Z);said first and second slide guides (32,33) being configured to be slidably coupled with said first and second carriages (31 a, 31b) so as to enable a movement of the aforesaid carriages (31 a, 31b).

6. The machine (100) according to claim 5, wherein said drive means (50) comprise:- an electric motor (51 ), and- a screw mechanism extending along said second axis (Z-Z) and connected to said electric motor (51) in order to be driven; said screw mechanism comprising a threaded bar (52’) and a nut (52”) slidably mounted on said threaded bar (52’) mechanically connected respectively to each of said first and second carriages (31 a, 31b) to enable a movement thereof along said first and second slide guides (32,33).

7. The machine (100) according to claim 6, wherein said screw mechanism is of the recirculating ball type or the trapezoidal screw type.

8. The machine (100) according to any one of the preceding claims, wherein at least one of said first and second sealing bars (30a, 30b) comprises at least one force transducer;configured to measure a force applied by said first and second sealing bars (30a, 30b) on the film during the packaging of a sofa.

9. The machine (100) according to claim 8, wherein at least one of said first and second sealing bars (30a, 30b) comprises at least one pair of force transducers (70a, 70b) connected to each other and cooperating to measure a force applied by at least one of said first and second sealing bars (30a, 30b) on the film during the packaging of a sofa.

10. The machine (100) according to claim 9, wherein at least one of said first and second sealing bars (30a, 30b) comprises a first and a second pair of force transducers (70a, 70b) mounted on at least one of said sealing bars (30a, 30b) in a position opposite each other;said first and second pair of force transducers (70a, 70b) being positioned in end portions of said at least one sealing bar (30a, 30b).

11. The machine (100) according to any one of claims 8 to 10, wherein each force transducer is a load cell.

12. The machine (100) according to any one of the preceding claims, wherein said packaging station (30) comprises at least one position sensor (80), connected respectively to at least one of said first and second carriages (31 a, 31b) and configured to detect a distance of at least one carriage (31 a, 31b) along said second axis (Z-Z) relative to a respective predefined reference position of said at least one carriage (31a, 31b).

13. The machine (100) according to any one of the preceding claims, wherein at least one of said first and second sealing bars (30a, 30b) comprises at least one pneumatic cylinder (90) configured to pressurise each of the sealing bars (30a, 30b) when they are abutted against each other in said closed configuration, in order to press edges of film between them and seal them.

14. The machine (100) according to any one of the preceding claims, wherein said packaging station (30) comprises a cutting means slidably mounted on at least one of said sealing bars (30a, 30b) and configured to cut edges of film previously sealed together,said cutting means being vertically movable along a third axis (W-W) which is orthogonal to said first and second axes (Y-Y, Z-Z).

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