Packaging system for spreading a tubular film of plastic material on a product to be packaged

Abstract

Packaging system (100), comprising: - an entrance roller conveyor (101); - a mobile portal (102), crossed by a product to be packaged pushed by the entrance roller conveyor (101); - an exit roller conveyor (105) on which the packaged product is located; - a support (103) of a plastic film; - a first welder mounted on the support (103) and a second welder aligned with the first welder and positioned on the exit roller conveyor (105); - a roll (104) of the plastic film which is taken from the mobile portal (102); and - at least four extenders (106) configured to unwind and drag the plastic film. Each extender (106) comprises: an unwinder comprising a motor (106a), a film collection wheel (106b), a pneumatic cylinder (106d) and a film accumulation plate (106c).

Description

[0001] PACKAGING SYSTEM FOR SPREADING A TUBULAR FILM OF PLASTIC MATERIAL ON A PRODUCT TO BE PACKAGED

[0002] The present invention relates to a packaging system .

[0003] In particular, the present invention refers to a packaging system of the type that spreads a tubular film of plastic material on a product to be packaged .

[0004] As is known, there are various systems for wrapping or packaging obj ects based on the spreading of a plastic film for packaging .

[0005] A first known solution is reported in patent application WO2019042513A1 which describes a system for packaging obj ects on a conveyor using a tubular plastic film . More in detail , in the system this tubular plastic film can be wrapped around obj ects along a hori zontal direction . The system comprises a gripping unit provided with a plurality of hori zontally oriented gripping arms , to hold the tubular plastic film and to release it onto an obj ect , and a first conveyor to support the obj ect and transport it towards the gripping unit in an axis parallel to the gripping arms so that the obj ect is positioned between them . The system is equipped with a second conveyor to support the obj ect and remove it from the gripping unit , a second conveyor which is placed near the gripping unit , which during the packaging phase is placed between the first and the second conveyor . Elements are also provided, capable of cooperating with each other to temporarily retain the film, which enclose a cutting device and a welding device and which are positioned at the end of the first conveyor . The packaging system also includes a control unit .

[0006] A second known solution is reported in patent application EP3115302A1 which describes a machine and a system for the vacuum packaging of products , where a plurality of bags is generated, closed at one end and open at the opposite end, with at least one product inside . For the generation of bags , a transverse cut and a complete transverse seal are performed on a tubular film on both sides of the transverse cut , and a transverse cut , without complete transverse seals , is performed on the sides of the same transverse cut at a distance . It is substantially equal to the desired length of the bag, which is defined by means of transversal cutting and welding on both sides . Each bag is oriented at 180 ° with respect to the previously generated bag, along an ' X ' direction of advancement . A third known solution is reported in patent application ITMI20080730A1 which describes a machine for packaging products in a heat-sealable film, in which at least one film ribbon forms a tube of said film around a sequence of products , and which includes a group longitudinal welding of the lateral edges of the film to close the tube laterally, and a transversal welding unit of the film tube between the products . The sealing units include sealing surfaces intended for contact with the film, which are heated by electrical resistors to a sealing temperature and which are supported and operated by movement means for their sealing movement with respect to the film . The machine is characteri zed in that the welding surfaces with the respective electrical resistances of at least one of the welding groups form a welding body, which is separated from the respective movement means by the interposition of a body of thermally insulating material .

[0007] A fourth known solution is reported in the patent application ITB020040253A1 which describes a machine for wrapping groups of products with pieces of tubular stretch film, comprising a rotating carousel equipped with a plurality of packaging groups , in turn equipped with bars for tailor-made expansion a succession of the aforementioned segments , fed to a feeding station S I . The machine also includes a station S3 for positioning the lengths of tubular film, spread around respective groups of products to be packaged, fed in sequence to the station S3 , and a station S4 for unloading the groups of packaged products from the carousel . The machine is characteri zed by the fact that it includes a station S2 , dedicated to the expansion of the film sections , with the bars which complete at least the operation of expansion of the same film sections at said station S2 .

[0008] However, these systems have the limitation that the positioning of the extender groups is not easily adj ustable and that the sliding of the plastic film is not optimal , also resulting in cuts and tears in the film .

[0009] Also , a packaging system is described in US2017 / 334586A1 . The system disclosed in US2017 / 334586A1 comprises a fixed motor, to which a tilting support is attached, said support being moved by a pneumatic cylinder . The aforementioned support is composed of two lateral blocks , 3 wheels and a strap . The system is completed by two wheels / rollers placed on the film support . The main problem of the disclosed system i s to be complex in terms of number of components and of their overall si ze , resulting in di f ficulties both in the packaging and maintenance phases and also an increasing of construction costs . Finally, the system described in US2017 / 334586A1 has the problem of comprising metal elements that can cause mark, scratch or other damage to the packaging film .

[0010] The aim of the present invention is to provide a packaging system, capable of providing adj ustable positioning of the extender groups and optimal sliding of the plastic film, therefore having characteristics such as to overcome the limits of current systems .

[0011] According to the present invention, a packaging system is provided, as defined in claim 1 .

[0012] For a better understanding of the present invention, a preferred embodiment is now described, purely by way of non-limiting example , with reference to the attached drawings , in which :

[0013] - figure 1 shows a schematic perspective view of a packaging system, according to the invention;

[0014] - figure 2 shows a first schematic sectional view of a mobile portal of the packaging system, according to the invention;

[0015] - figure 3 shows a schematic view of a sliding portion of a plastic film of the packaging system, according to the invention; - figure 4 shows a schematic view of the plastic film unwinding units of the packaging system, according to the invention;

[0016] - figures 5A-5B show schematic side views of one of the four plastic film extender groups in a first position, according to the invention; figures 6A- 6B show schematic side views of the extender assembly of figure 5 in a second position, according to the invention .

[0017] With reference to figure 1 , a packaging system 100 is shown, comprising : an inlet roller conveyor 101 ; a mobile portal 102 which can be moved from left to right moving towards the entrance roller conveyor 101 ; an exit roller conveyor 105 ; a first welding machine mounted on a support 103 of a plastic film positioned in front of the mobile portal 102 and a second welding machine aligned with the first welding machine and positioned on the exit roller conveyor 105 , as shown in figure 3 ; a roll 104 of the plastic film which is taken from the mobile portal 102 . More in detail , in front of the support 103 , four extenders 106 are positioned on the mobile portal 102 .

[0018] According to one aspect of the invention, two motors are present on the support 103 . According to one aspect of the invention, the extenders 106 are positioned on parallel vertical structures 112a and 112b .

[0019] The presence of a second welder al igned with the first is not an obvious configuration .

[0020] In fact , di f ferent configurations of the welding machine are possible , for example , a second welder fixed on the outgoing roller conveyor advanced compared to the first welder on the roll support or set back from the first welding machine on the roll support .

[0021] Said configuration are not optimi zed for the scope of the invention for the following reasons . The solution with a second welder advanced compared to the first welder on the roll support has the problem that, by moving the sealer away, there is an additional empty between the two roller conveyors , not allowing small products to be packaged

[0022] The configuration that comprises a second welding machine set back from the first welding machine on the roll support has the problem that , by bringing the welding machine closer, the film supports should be shortened, not allowing large products to be packaged

[0023] Another possible configuration is that the second welder is mobile on the portal and positioned behind the supports . Said configuration has the problem of creating, during the packaging phase , an empty space between the product and the welding machine , causing as a consequence a lot of waste material .

[0024] The solution proposed by the invention, that is o f positioning a second welder in line with the first welder , is a result of an optimi zation study carried out by the Applicant , with the aim of expanding as much as possible the packaging range and obtaining a machine that optimi zes consumption of packaging material .

[0025] As shown in figure 2 , the mobile portal 102 includes : - a motor 107 positioned on one side of the frame of the mobile portal 102 configured to move the mobile portal 102 from right to left ; - two motors 108a and 108b positioned before the first sealer, in front of the roll 104 and configured to unwind its film; - a motor 109 positioned on the mobile portal , above the motors 108a and 108b, and configured to control the opening of the extenders 106 , and, in particular, to bring together the two parallel vertical structures 112a and 112b, on each of which there is positioned an upper extender 106 at a variable height with respect to the floor, with a height that can be modi fied by the motors 110a and 110b, and a lower extender 106 at a fixed height with respect to the floor ; - a motor 110a positioned on the vertical structure 112a and configured to li ft the extender 106 positioned on the vertical structure 112a and a motor 110b positioned on the vertical structure 112b and configured to li ft the extender 106 positioned on the vertical structure 112b .

[0026] Two of the motors 106a of the extenders 106 are connected to the vertical structure 112a and two other motors 106a of the extenders 106 are connected to the vertical structure 112b and configured to collect the film on the extenders 106 .

[0027] In particular, during operation, in a first phase , the mobile portal 102 moves completely to the left , the motor 109 brings the vertical structures 112a and 112b closer together and the motors 110a and 110b lower the mobile upper extenders 106 towards the lower extenders 106 fixed; in a second phase the mobile portal 102 moves completely to the right , the motor 109 moves the vertical structures 112a and 112b away from each other and the motors 110a and 110b raise the mobile upper extenders 106 .

[0028] According to an aspect of the invention, as shown in figure 5 , the extender 106 includes : - an unwinder comprising a motor 106a for collecting / unwinding the plastic film, a film collection wheel 106b, a pneumatic cylinder 106d for motor movement ; and - a film accumulation plate 106c . In use , in a first phase , as shown in figures 2 and 3 , there is no physical connection between the portal 102 and the roll 104 . The plastic film is pushed by the two motors present on the support 103 and without any help it rests on the accumulation plates 106c . Once the film slides for approximately 15cm on the accumulation plates 106c, it is dragged by the unwinders of the extenders 106 .

[0029] A product to be packaged, present on the inlet roller conveyor 101 , moves through the portal 102 pushed by the same roller conveyor 101 . The portal 102 never comes into contact with the product . Once the packaged product is on the exit roller conveyor 105 , a welding machine is activated and the portal 102 returns in the direction of the film support 103 to start the cycle again .

[0030] The plastic film is unwound from its roll and collected on the unwinders for then be welded and cut at the top by the welding machine present on the support 103 . At this point the unwinders extend the film up to the set height and the portal 102 moves from the film support area until it is in line with the inlet roller conveyors 101 and exit 105 . The extenders 106 are made to go up / down and moved to the right / left by the motors present on the portal 102 . The inlet roller conveyor 101 therefore advances the product to be packaged and, at the same time , the motors 106a present on the extenders 106 carry out the previously collected film .

[0031] When the product to be packaged completely passes through the portal 102 , the roller conveyors stop to allow the second welding machine present on the exit roller conveyor 105 to seal and cut the film at the end . The package thus formed is advanced to the end of the line to be picked up . To collect the film from the support 103 , the extenders 106 are moved, i . e . made up and down and moved to the right and left by the motors present on the portal 102 and positioned in such a way that the accumulation plates 106c are in line with the four edges of the tubular film and, thanks to the pneumatic cylinder 106d, the motor 106a is pushed into a first position, shown in figures 5A and 6A. Once in position, a small amount of film is pushed towards the extenders 106 and, when the film is in the direction of the collection wheel 106b, the pneumatic cylinder 106d moves the motor to a second position shown in figures 5B and 6B, in such that the collection wheel 106b is in contact with the accumulation plate 106c . The film is then accumulated on the respective plates 106c .

[0032] According to one aspect of the invention, the motor 106a is tilting, and the dragging of the film is entrusted to the wheel 106b mounted directly on the axis of the motor 106a .

[0033] In particular, the wheel 106b can only have two positions with respect to the film support , either it is in contact with it or it is detached from it . Therefore it is necessary to correctly adj ust the positions only when the wheel 106b is in the second position .

[0034] Advantageously, the packaging system allows the film collection area to be freed up as much as possible , so that a lot of film can be collected in a small space on the supports . This advantage is provided by the fact that motors for moving the extenders are installed on the gantry and by the fact that the accumulation plates are in line with the plastic film . Thanks to this feature of the invention, the packaging system is able to package large parcels (up to approximately 5 meters ) with short length extenders ( approximately 50 cm) .

[0035] Another advantage of the invention is of requiring reduced spaces for the entire packaging system .

[0036] Also , the solution according to the invention allows a reduction of components number and complexity, an ease of maintenance , and protection of the packaging film .

[0037] Another advantage of the invention is that it comprises two fixed-height supports and two variable-height supports placed in pairs on two vertical structures ( 112a and 112b ) that move closer / further from each other . Those features allow to obtain maximum f lexibility in positioning the supports ( in case of the six extender solution) and at the same time to have few components and therefore to reduce costs and dimensions of the packaging system ( in case of the four extender solution) .

[0038] Therefore , the packaging system according to the invention allows the position of the unwinders to be easily adj usted .

[0039] Furthermore , the packaging system according to the invention is economical .

[0040] Another advantage of the packaging system according to the invention is that it is easily maintainable , requiring only the replacement of the wheel in case of wear .

[0041] Finally, the packaging system according to the invention presents a better flow of the film which has neither cuts nor tears .

[0042] Finally, it is clear that modi fications and variations can be made to the packaging system according to the invention described and illustrated here without departing from the protective scope of the present invention, as defined in the attached claims .

Claims

CLAIMS1. Packaging system (100) , comprising:- an entrance roller conveyor (101) ;- a mobile portal (102) that can be moved from left to right moving towards the entrance roller conveyor (101) , crossed by a product to be packaged pushed by the entrance roller conveyor (101) ;- an exit roller conveyor (105) on which the packaged product is located; a support (103) of a plastic film positioned in front of the mobile portal (102) ;- a first welder mounted on the support (103) and a second welder aligned with the first welder and positioned on the exit roller conveyor (105) ;- a roll (104) of the plastic film which is taken from the mobile portal (102) ; and at least four extenders (106) positioned on the mobile portal (102) in front of the support (103) configured to unwind and drag the plastic film; characterized in that each extender (106) comprises: an unwinder comprising a motor (106a) for collecting / unwinding the plastic film, a film collection wheel (106b) configured to drive the plastic film mounted on the shaft of the motor (106a) , a pneumatic cylinder(106d) configured to move the motor (106a) ; and - a film accumulation plate (106c) configured to house the plastic film pushed by the motor (106a) .

2. Packaging system (100) according to claim 1, characterized in that the extenders (106) are moved by the motors present on the portal (102) and positioned in such a way that the accumulation plates (106c) are in line with the four edges of the plastic film.

3. Packaging system (100) according to claim 1, characterized in that the pneumatic cylinder (106d) is configured for:- pushing the motor (106a) into a first position, at which a predetermined amount of plastic film is pushed towards the extenders (106) ; And- when the plastic film is in the direction of the collection wheel (106b) , move the motor (106a) to a second position where the collection wheel (106b) is in contact with the accumulation plate (106c) .

4. Packaging system (100) according to claim 1, characterized in that the motor (106a) is tilting.

5. Packaging system (100) according to one of preceding claims, characterized in that the collection wheel (106b) can assume a first position in contact withthe accumulation plate (106c) or a second position detached from the accumulation plate (106c) .

6. Packaging system (100) according to one of preceding claims, characterized in that the extenders (106) are positioned on parallel vertical structures (112a, 112b) , an upper extender (106) being positioned at a variable height with respect to the floor and a lower extender (106) being positioned at a fixed height with respect to the floor.

7. Packaging system (100) according to one of preceding claims, characterized in that the mobile portal (102) comprises: - a motor (107) positioned on one side of the frame of the mobile portal (102) configured to move the mobile portal (102) from right to left; - two motors (108a, 108b) positioned between the first and second sealers in front of the roll (104) and configured to unwind its film; a motor (109) positioned on the mobile portal, and configured to command the opening of the extenders (106) , and, in particular, to bring the two parallel vertical structures (112a, 112b) closer together; - a motor (110a) positioned on the mobile portal and configured to raise the upper extender (106) positioned on the vertical structure (112a) and a motor (110b) positioned on the mobile portaland configured to raise the lower extender (106) positioned on the vertical structure (112b) .

8. Packaging system (100) according to one of preceding claims, characterized in that two of the motors (106a) of the extenders (106) are connected to the lower part of the vertical structure (112a) of the portal and two more motors (106a) of the extenders (106) are connected to the lower part of the vertical structure (112b) .

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