Serial assembly of connected bags made of textile for feeding an automatic bag-filling machine, and a method for feeding said bags

Abstract

A serial assembly (100) of connected bags (110; 120) made of textile for feeding an automatic bag-filling machine wherein each pair of two consecutive bags is connected by a releasably coupling joint (115) disposed between two consecutive bags. The releasably coupling joint is formed by at least one strip of fabric made of a different material as the textile of the bag and having a tensile strength capable of withstanding a predetermined tensile force applied by the bag-filling machine upon unwinding the serial assembly.

Description

[0001] Serial assembly of connected bags made of textile for feeding an automatic bag-filling machine, and a method for feeding said bags.

[0002] The invention relates to the field of packaging food products such as (dried) fruits, vegetables, tea, coffee, etc. In particular, it relates to a serial assembly of connected bags made of textile for feeding an automatic bag-filling machine and a method for feeding a machine with the serial assembly of connected bags and filling each bag with (dried) fruits, vegetables, tea, coffee, etc.

[0003] The packaging of some food products, like (dried) fruits, vegetables, tea and coffee in bags made of bast fibres, such as jute, is well known. These bags typically consist of a fabric made from plant or bast fibres such as jute, kenaf, hemp, flax, sisal, for example. The advantages of using plant fibres, including bast fibres, are numerous and include, but may not be limited to air permeability, which limits condensation and therefore the degradation of the contents, resistance to heavy loads, reusability, 100% compostable, and a low carbon footprint, for example.

[0004] Despite its obvious qualities, the sale of jute and other natural fibre-based products has been eclipsed by plastic in the mass retail sector in recent decades. The reason is largely economic: the simplicity of manufacture and the possibilities of automated filling of plastic bags have led to annual global consumption of 500 billion plastic bags.

[0005] The current climate crisis and pollution in the oceans have brought a critical look at the overuse of plastic and its harmful impact on the environment . Thus , it should be no surprise that sacks made from natural textile fibres are gradually making a comeback . However, they do not yet meet the mass packaging requirements for which plastic is well suited . In fact , many machines allow 100% automation of food packaging by being fed by a continuous roll of plastic film or net , which is then dissociated to discrete bags . New automation machines and processes are emerging for bags made from natural textile fibres , but there are still problems regarding their democratisation and wide-scale implementation and acceptance .

[0006] For example , patent application WO2018088578A1 discloses a robot automatic packaging machine designed for filling j ute bags . A first problem arises from the supply of bags to the machine , which are supplied unit by unit , unlike the continuous rolls of plastic film or net . A second problem is that this kind of new process requires new machinery, whereas most producers / packers are already equipped with packaging machines adapted to plastic . It there fore seems illusory in the short and medium term to envisage replacing plastic with sustainable products i f the only solution is to replace the machines currently in use with machines that are not necessarily more ef ficient .

[0007] US2002021844A1 describes the design of an enhanced open-mesh plastic bag made from a base material roll , reinforced with thermoplastic strips applied along the side seams . However, it is limited to open-mesh plastic bags and does not consider the use of natural fibre textiles . Additionally, the thermoplastic strips are directly af fixed to the base material , a method distinct from the approach disclosed herein . Final ly, US2002021844A1 does not address the possibility of feeding a filling machine with a connected set of bags j oined by linking strips .

[0008] US2022160145A1 details a reusable bag distribution system made of textile material from natural , semi-natural , or synthetic fibres . These bags can be presented as rolls or folded stacks . In the case of rolls , the bags are connected detachably via perforations , detachable adhesives , or stitches , requiring minimal ef fort for separation . However, the method described in US2022160145A1 is not compatible with configurations where the connection between bags must withstand tensile stress in a filling machine . Furthermore , this document does not contemplate the use of these bags with filling machines , focusing instead on manual distribution for individual bag removal .

[0009] GB682388A introduces a method for reinforcing woven bags , possibly made of j ute , with linking strips . These strips , composed of two fabric layers , are woven between two bag sections with modi fied weaving to reverse warp threads , temporarily connecting the bags . The strips are then cut , folded, and glued to reinforce the bags and prevent fraying . In contrast , the linking strips in GB682388A are made of the same material as the bags , which di f fers from the method disclosed herein . Moreover, the set of bags described is not designed for integration with a filling machine but for separation and individual use after production .

[0010] US2022106095A1 describes reusable , eco- friendly bags made from biodegradable materials such as wood, designed to be compatible with existing supports for traditional plastic bags in grocery stores . It also discusses produce bags that can be connected into a roll for mounting on these supports . Similar to US2022160145A1 , the connections between bags are designed for easy detachment without requiring signi ficant user ef fort . Additionally, US2022106095A1 does not indicate that these bags are intended to supply a filling machine .

[0011] The prior art reveals several limitations in the design and functionality of bag systems . For instance , US2002021844A1 is restricted to open-mesh plastic bags and lacks cons ideration for natural fibre textiles , while its method of reinforcement is incompatible with advanced bag handling systems . Similarly, US2022160145A1 and US2022106095A1 describe detachable bag connections optimi zed for manual separation, but these connections cannot endure the mechanical stress required in filling machines , nor do they address integration into automated filling processes . Furthermore , GB682388A focuses on reinforcing woven bags with linking strips made of the same material , but its configuration is unsuitable for continuous feeding into a filling machine , as the linking strips are designed for post-production separation rather than operational integration . Collectively, these prior art references fail to address the need for robust , interconnected bag systems capable of supporting ef ficient , automated filling operations while accommodating diverse materials and structural enhancements .

[0012] The applicant therefore considered it necessary to develop a serial assembly of connected bags that overcomes the limitations of the prior art .

[0013] Solution of the invention

[0014] To this purpose the invention relates to a serial assembly of connected bags made of textile for feeding an automatic bag- filling machine , characteri zed in that each pair of two consecutive bags of the serial assembly is connected by a releasably coupling j oint disposed between two consecutive bags , and wherein the releasably coupling j oint is formed by at least one strip of fabric made of a di f ferent material as the textile of the bag and having a tensile strength capable of withstanding a predetermined tensile force applied by the bag- filling machine upon unwinding the serial assembly .

[0015] The serial assembly of connected bags of the invention allows the automation of filling textile bags in the same manner as filling non textile plastic bags , and preferably on the same machines . Despite not having the same thermal characteristics as conventional plastic bags , the present invention in both its device and method nevertheless enables existing machinery to easily adapt to the textile material . Generally, known automation machines are well adapted to plastic bags including being adapted to the thermal properties , among other properties , of plastic bags . The fact that the releasably coupling j oint is formed by at least one strip of fabric made of a di f ferent material as the textile of the bag enables to select for this di f ferent material one that has a tens ile strength capable of withstanding a predetermined tensile force applied by the bag- filling machine upon unwinding the serial assembly . In such a manner the connection between the successive bags will not be broken by the tensile force appl ied by the bag- filling machine upon unwinding . The di f ferent material used for the releasably coupling j oint also allows this j oint to be released in more favourable conditions than i f the j oint comprised the same textile material as the bags , particularly for bags made of natural materials , such as j ute , which are not suitable for either thermal cutting because o f the risk of fire or mechanical cutting because of the rapid degradation of the blade .

[0016] One aspect of the present invention is to enable a serial assembly of connected bags to be run preferably through existing automation equipment with little or no modi fication to the equipment . However, the invention is not limited to existing machines , and the serial assembly of connected bags according to the invention can be provided for new machines .

[0017] The textile material is preferably made of natural textile fibres such as bast fibres including, but not limited to , j ute or sisal , or cellulose based fibres like cotton, hemp, wool , blends of the aforementioned cellulose-based fibres , and other similar textiles . One important goal is to replace plastic with a reusable and compostable material .

[0018] In certain embodiments it can be preferred to use natural textile fibre materials for the bags . In other certain embodiments it may be preferred to use a blended textile material .

[0019] The textile material is preferably a woven material , more preferably a natural woven material , whether unblended or a blended mix of both natural fibres and synthetic fibres . For certain products , notably food products , moisture trapped by conventional plastic materials is highly undesirable . In contrast , woven textile materials have a natural air permeability, and this reduces condensation inside the bag and therefore degradation of the contents of the bags can be kept to a minimum . Alternatively, the textile material can be composed of synthetic textile fibres such as preferably biodegradable synthetic fibres or fibres made of recycled plastic .

[0020] The textile material can be made of a mix of fibres : for example , at least two natural textile fibres , at least two synthetic textile fibres or at least one natural fibre and at least one synthetic fibre .

[0021] As is generally understood in the art of packaging foodstuf f , the selection of materials for the packaging largely depends on the preservation requirements of the foodstuf f contained therein and, additionally, must not contaminate the contents . Additionally, the mesh si ze of the woven textile fibres can also be adapted according to the weight of products the bag can contain and / or how the bag will be used . A tight mesh facilitates printing thereon and increases the mechanical strength including pulling resistance and resiliency of the bag, whereas a wide mesh more ef ficiently reduces condensation and may even allow the contents to be seen .

[0022] The type of fibre ( s ) combined to create the mesh determine the overall strength of the bag . For the purposes of packaging automation, a bag must be able to withstand the tensile force it undergoes during the fill ing process . And, of course , any bag must be strong and sturdy enough to enable the end-user to safely transport the contents of the bag .

[0023] A bag, in an advantageous embodiment , is made of at least one material , and this material can be j ute . In a preferred embodiment , the material of the bags i s predominantly composed of j ute , preferably more than 80% , more preferably more than 90% , more preferably more than 95% .

[0024] A bag is generally characteri zed by having an open top, at least two oppositely arranged faces forming vertical walls of the bag and delimiting the open top, and a closed bottom opposite from the open top . The closed bottom can for example be created by folding a single piece of material . In such a case , the single piece of material forms the two oppositely arranged faces . To form a bag suitable for holding contents , the single piece of material would require a seam or other sort of j oint that extends vertically along both edges of the opposing faces . No bottom seam or j oint would be required . The invention is not limited to the specific configuration of bags described herein, such as those featuring a folded bottom and side seams . A person skilled in the art will understand that other bag configurations or designs capable of achieving similar functionality are also considered to fall within the scope of the invention .

[0025] In one contemplated embodiment , a serial assembly of connected bags enables the use of conventional automation equipment to provide the bags as required, for example , to fill the bags with potatoes . In this example , each bag comprises the open top, the closed bottom, the two faces and two lateral edges thereof along which the two faces of the bag connect from bottom to top, j ust as a person skilled in the art would find inherent in the manufacturing processes of conventional bags , as well as the bag of the present invention . The lateral edges at which the two faces connect are preferably two side seams . Alternatively, at least one of the lateral edges can be either a fold in the textile or a further strip of textile sewn to both faces .

[0026] Optionally or alternatively, the bottom of the bag can either be a fold in the textile or a further seam .

[0027] Preferably, the seams ( and bottom seam, i f having one ) consist of a yarn thread, such as for example nylon, which is selected for its characteristic of strength, wide availability, and low price .

[0028] In one contemplated embodiment , the thread consists entirely of nylon, and because it is used in a low proportion with respect to the remainder of the bag material , the bag would still be considered compostable .

[0029] Alternatively, or optionally, other types of threads could work equally well including threads made entirely from natural and / or biodegradable materials , synthetic materials , or any combination of biodegradable and synthetic materials , for example . Also , any other sewing thread can be used for the seams , provided the thread is selected to withstand the tensile force undergone by the bag during the filling process .

[0030] The serial assembly of connected bags comprises at least two bags connected in series in consecutive way, i . e . one after the other .

[0031] Preferably, the serial assembly of connected bags comprises a plurality of bags wherein the consecutive bags are each time connected by a releasably coupling j oint extending as from the bottom towards the top along the lateral edges of the bags and disposed between two consecutive bags . In other words , the bags are releasably coupled or otherwise connected to each other at their lateral edges , for example at their side seams . This releasable coupling j oint enables two consecutive bags to be separated by a mechanical cutting, thermal cutting, shearing, slicing, tearing, or by other cutting means as would be conventionally used in similar configurations of conventional plastic bags or as is suitable for fabrics .

[0032] Alternatively, the serial assembly of connected bags comprises at least two bags connected by having the top of one bag connected to the bottom of the subsequent bag . This connection is also reali zed by the releasably coupling j oint disposed between the top and the closed bottom of the two consecutive bags . Accordingly, the releasable coupling j oint enables two consecutive bags to be separated by mechanical cutting, thermal cutting, shearing, slicing, tearing, or by other cutting means as would be conventionally used in similar configurations of conventional plastic bags or as is suitable for fabrics .

[0033] The serial assembly of connected bags can be arranged as a roll of bags around a hollow cylinder or chuck that can be used on suitable automatic bag- fill ing machines , for example on machines already available on the market for the automatic filling of plastic film or plastic net bags . It should be further understood that a roll of bags need not rely on a hollow cylinder or chuck on which to roll - in other contemplated embodiments , no such cylinder or chuck is required to form a suitable roll of a plurality of releasably coupled adj acent bags . Alternatively, the serial assembly of connected bags can be arranged in a manner other than as a roll to feed an automatic bag-filling machine suitably adapted. For example, the serial assembly can be accordion folding.

[0034] The releasably coupling joint is preferably applied on the lateral edges of two consecutive bags. It is, for example, sewn or glued or otherwise mechanically coupled or chemically bonded, along the lateral edges of the respective bags. In an optional or alternative version, the releasably coupling joint is formed by a strip of fabric of which an edge section is inserted between the edges of the two faces of the bag and interconnected with the lateral edge of the bag. There is then, for example, only one sewing operation for manufacturing the bag and applying the releasably coupling joint.

[0035] The size of the releasably coupling joint further serves to define the distance between two consecutive bags. In a first embodiment, the joint is a single strip of fabric sewn on one lateral edge of a first bag and this same single strip of fabric is also sewn to a lateral edge of a second bag consecutive to the first bag. The strip of fabric is, for example, arranged to separate or otherwise space-out adjacent bags from between 0.5 to 10 cm, preferably between 0.7 cm and 5 cm. The strip can cover the entire height of the bag or only a fraction of the height of the bag.

[0036] The releasably coupling joint can also be a plurality of strip segments, that is, one or more strip segments are applied in a discontinuous manner along a side of the bag. This allows to save on the quantity of fabric or textile needed for the releasably coupling joint. Alternatively, the releasably coupling j oint is formed by two strip shaped pieces made of a textile or fabric . A first one of those two pieces being attached along the length of one lateral side of a first bag and the second one of those two pieces being attached along the length of one lateral side of a second subsequent bag . The two strips are then sewn together along their free side to connect them to each other , thereby connecting two subsequent bags to each other . Although this implies more sewing, it has the advantage of enabling the coupling of the subsequent bags separately from the manufacturing of the bag itsel f .

[0037] In case the releasably coupling j oint is one or more preferably several , elements of fibrous material , such as cord, rope , string, or threads , thi s j oint can then be arranged at any desired height along the bag lateral edge and is fixed to the bag by any suitable means , including, for example , sewing, gluing, stapling, or other mechanical fastening techniques .

[0038] In use , the serial assembly of connected bags will undergo a travel through machines , which implies that a predetermined tensile force will be applied by the bag- filling machine upon unwinding the serial assembly . The releasably coupling j oint must therefore have a tensile strength suf ficient to withstand the tensile force exerted by the machine as it unwinds the bags . The required tensile strength cannot be limited to a fixed value , as it depends on multiple factors that vary with each speci fic application . These factors include , but are not limited to , the design and operation parameters of the machine , the si ze and weight of the bags , the total weight of the serial assembly, the textile material of the bags , the dimensions and volume capacity of the bags , and the mass density of the products with which the bags are filled . A person skilled in the art will understand how to select an appropriate material and structural configuration for the releasably coupling j oint based on these variables , ensuring that it meets the necessary mechanical resistance for a given use case . While preferred embodiments are described below, they are not limiting, as di f ferent applications may require adj ustments to optimi ze performance .

[0039] One suitable and contemplated j oint additionally or alternatively includes a non-woven polypropylene material or cotton in case of a thermal cutting . Alternatively, i f a cutting blade is used to cut the j oint , it can comprise polyester . In particular, when the coupling j oint is made from a non-woven polypropylene fabric, the tensile strength may fall within a broad range , typically between 1 MPa and 50 MPa, depending on the material ' s composition, weight , and bonding method . More speci fically, for lightweight fabrics ( 10-50 gsm) , the tensile strength may range from 1 MPa to 10 MPa ; for medium-weight fabrics ( 50-100 gsm) , from 10 MPa to 30 MPa ; and for heavier fabrics ( above 100 gsm) , from 30 MPa to 50 MPa . The tensile strength of the releasably coupling j oint is preferably comprised between 1 and 50 MPA, preferably between 5 and 50 MPa, preferably between 10 and 50 MPa, preferably between 15 and 50 MPa, preferably between 20 and 50 MPa , preferably between 25 and 50 MPa, preferably between 30 and 50 MPa, preferably between 35 and 50 MPa and preferably between 40 and 50 MPa . Within these ranges , further refinement can be made based on additional parameters such as fibre orientation, bonding techniques , or any reinforcements appl ied to the material .

[0040] The releasable coupling j oint preferably comprises at least two sections , a lower section extending upwards from the bottom and an upper section extending downwards from the top . Preferably, the connection between the two faces of each bag at the lateral edges do not extend over the full height of the bag . A portion of the connection situated at the top of the lateral edges of the bag remain unconnected, for example a few centimetres , like 3 to 10 cm, leaving an aperture between two consecutive bags . This facilitates the opening of the bag when on the loading line . Indeed, frequently, the top borders of the two faces of the bag are guided through rails and pulled apart to allow the content to be inserted in the bag . To ensure the continuity on the top border of the assembly, the upper section of the j oint , extending downwards from the top, comprises two parallel strips of fabric each connecting a face of a bag to a corresponding face of the consecutive bag without obstructing the aperture .

[0041] It is understood that for a machine where the aforementioned aperture would not be necessary, there would be no need to di f ferentiate between the upper and lower sections of the oint .

[0042] Optionally or alternatively, each bag can also include or otherwise comprise one or more handles to make the bag easier to carry . The handles can be integrated into the bags in a variety of ways , as would be well-understood by those having ordinary skill in this art .

[0043] In one preferred or optional embodiment , the handles consist of holes arranged in the top section of the bag, preferably centred on each face . The holes can be directly made in the textile used for manufacturing the bag or, alternatively, consist of an added strip of fabric that is sewn or otherwise mechanically fastened to the open top of the bag . For example , this added strip can then become the open top of the bag . In this case , the added strip can be preferably made of woven polypropylene . The surface of the added strip that contacts the fabric of the bag can then be coated or otherwise laminated with heat-bonded transparent OPP film . Alternatively, the fabric added strip is made of j ute , or other natural fibre , with a polyethylene film heat-bonded to side in contact with the fabric of the bag .

[0044] Optionally or alternatively, the handles can be cords or laces fixed to the bag by suitable means , depending for example on the weight of the filled bag .

[0045] The invention also relates to a method for feeding an automatic bag- filling machine with a serial assembly of connected bags according to the invention and for filling the bags with a product , this method comprising the following steps :

[0046] - positioning the serial assembly of connected bags at the input of a bag loading equipment ;

[0047] - inserting the top border of the first bag of the serial assembly into guide means , such as rails and / or rollers ;

[0048] - moving the bag towards a loading station, thereby applying a predetermined tensile force on the consecutive bag so that its top border is inserted into the guide means ,

[0049] - opening the top of the bag,

[0050] - supplying a predetermined amount of product through the top the bag for obtaining a filled bag,

[0051] - separating the filled bag from the serial assembly by applying a cutting on the releasable coupling j oint , and

[0052] - repeating the above steps for the next adj acent bag . Depending on the machinery, some steps , like cutting the j oint , may happen at a di f ferent stage and the order of the steps disclosed above is not limitative .

[0053] P_ s i t_i_o n i rig _ o_f _ t h_e _ s e_r i a 1_ _a s s_e mb l_y

[0054] The first step consists of positioning the serial assembly of connected bags in order to prepare for the continuous supply of bags during the filling process .

[0055] Preferably, the serial assembly of connected bags takes the form of a roll around a hollow cylinder ( chuck) and is placed vertically on a tray . The maximum diameter of the said tray limits the number of bags the rol l can hold . The larger the diameter, the greater the number of bags that can be contained and the less human activity is required to change the rol l when it is empty . Advantageously, the translation movements o f said hollow cylinder are blocked by means of a sleeve at its centre . Only the rotation movement along the axis of the cylinder is free to allow the bags to be unwound .

[0056] Alternatively, the serial assembly can be positioned in any way to ensure continuous feeding . For example , the assembly may be folded in an accordion shape and placed on a tray .

[0057] Positioning the first bag of the assembly at the input of a bag-loading unit / equipment comprises inserting ( the top edge of ) the first bag into guide means .

[0058] Preferably, the guide means are rails between which the upper edge of the first bag is inserted . The guide means can alternatively be rollers or comprise rollers through which the first bag passes .

[0059] Once the first bag is inserted, when it is moved towards the guiding station, the consecutive bags will follow and become inserted in the guide means .

[0060] Cut t i jag _ the _ j_q i n t

[0061] The releasably couple j oint between bags can comprise one or more parts .

[0062] When the bags are connected by their lateral edges , the step of cutting the j oint can comprises separating the lower section of the bags by cutting the lower section of the j oint prior to filling the bags . Separating the lower section of the bags before filling reduces stresses during filling with contents that may be heavy and bulky . The upper section of the j oint is then for example cut after filling in order to separate the filled bag .

[0063] Preferably, the cutting is a thermal cutting by a laser beam . In other words , the releasably coupling j oint , which is disposed between two consecutive bags , is cut under the ef fect of heat by melting the material of the coupling j oint .

[0064] Alternatively, the cutting is a mechanical cutting by a cutting blade .

[0065] Open i rig _ the _ _ _t qp_ _qf _ the _ ba

[0066] Opening the top of the bags is performed by pulling the two sides apart and maintaining thi s opening by spacer means for enabling filling . The opening must be large enough to allow the contents to enter the bag during filling .

[0067] Preferably, the spacer means are inserted through the gap between the two faces and push them apart to create a wider opening . The opening is then maintained until the filling stage is finished .

[0068] Alternatively, the filling means can hook onto the outside of each face on the upper section of the bag and create the opening by pulling each of the faces outwards . The opening is then maintained until the filling stage is finished .

[0069] Supp l_y ing_ _o f _ _t? he_ jpr oduc t_ _t o _ the _ b_a g

[0070] Preferably, the contents are first weighed, to obtain the desired quantity, before falling into the bag via a suitable mechanism . This mechanism can, for example , be a trap door that opens when the desired quantity is reached .

[0071] Clo s i rig _ the _ b_a g s

[0072] Optionally, a further step comprises closing the open top o f the bag . This step prevents the bag from being emptied of its contents later .

[0073] Preferably, the closure is made by sewing the top edge of the bag .

[0074] Alternatively, the closure can be made using a knot or any other means known to a person skilled in the art for closing a bag . Detailed description of the invention

[0075] The invention will be better understood with reference to the drawings where :

[0076] Figure 1 illustrates a serial assembly of two connected bags connected from bottom to top along the lateral edges ;

[0077] Figure 2 is a cross-sectional view along line A-A of Figure 1 ;

[0078] Figure 3 is a cross-sectional view along line B-B of Figure 1 ;

[0079] Figure 4 illustrates a serial assembly of two connected bags connected top to bottom;

[0080] Figure 5 is a profile view of a serial assembly of two connected bags connected top to bottom;

[0081] Figure 6 is a serial assembly of connected bags arranged in the form of a roll around a hollow cylinder ;

[0082] Figure 7 is a serial assembly of connected bags arranged like an accordion;

[0083] Figure 8 is a schematic diagram of a method using a serial assembly of connected bags according to the invention .

[0084] Figure 9 illustrates a serial assembly of three connected bags and indicates a feed direction of the series of bags as might be used in conventional automated bag- feeding machines .

[0085] Figure 1 shows a serial assembly 100 of two connected bags comprising a first bag 110 , a second bag 120 , and a releasably coupling j oint 115 disposed between the first bag 110 and the second bag 120 and coupling the first and second bags to each other .

[0086] In this example , each bag 110 , 120 comprises an open top 113 , 123 , a closed bottom 114 , 124 , two faces and two lateral edges 111,112,121,122 along which the two faces of the bag connect from bottom 114,124 towards the top 113,123. At their lateral edges the two faces are connected to each other by means of side seams. The closed bottom of the bag 114,124 can either be formed by a fold in the textile or by a further seam. In this example, the seams are made with nylon threads to ensure that the seams are strong enough when under tensile stress .

[0087] The bags are made of a textile material, preferably comprising natural fibres such as for example a woven textile material. The releasably coupling joint extends from bottom 114, 124 towards a top 113, 123 along the lateral edges 111, 121 of the bags. In the embodiment of figure 1 the releasably coupling joint comprises an upper section, extending downwards from the top and formed by two longitudinal strips 116 andl26. The releasably coupling joint further comprises a lower section, extending upwards from the bottom 114, 124 and formed by two longitudinal strips 115, disposed between the two consecutive bags 110 and 120. Each strip is made of a material which is different from the one of which the bags are made. The strips are mechanically fastened to the respective bags, for example inserted in the lateral seam of the bag. The bags 110 and 120 are connected to each other by sewing the strips of fabric 115 and 125 together.

[0088] Alternatively, the lower section is made by a single longitudinal strip instead of two strips. A first longitudinal border of this single strip is sewed to the longitudinal edge of one bag and the second longitudinal border, opposite to the first one, of this single strip is sewed to the longitudinal edge of a further bag subsequent to said one bag. The sewing of the lower section to the bags can be done either simultaneously with the one forming the longitudinal edge of the bag, or in a preceding or subsequent step.

[0089] Each bag also preferably comprises handles 117,127 that make them easy to carry. Consumers can also use the bags as shopping bags or for many other applications. In this case, for each bag, the handles are formed by holes made in the faces or by two further strips of woven polypropylene 118,119 applied on the top of the faces. The two further strips of woven polypropylene 118,119 are here sewn to the top edge of each bag to form the top opening 113,123. The side seams preferably do not extend until the open top to leave an aperture 130 between each bag. This aperture 130 is used during the bag filling process, as will be described hereinafter.

[0090] Figure 3 is a cross-sectional top view of the serial assembly of the two connected bags of figures 1 and 2 at the upper section of the joint. The upper section is more complex, as it must not block the aperture 130 described above, neither disturb the travelling of the bag upon filling them. To achieve this, the upper section 116, 126 of the joints is formed by two strip sections 1161 and 1162, applied on the right side of the bag and two strip sections 1261 and 1262 applied on the left side of the bag. The strip sections 1161 and 1162, respectively 1261 and 1262, are applied in parallel to each other. Two strips sections are sewn to respective faces of the bag. Then, the two corresponding strip sections of each bag 1162 and 1262 on one side, and 1161 and 1261 on the other side are sewn together to form the upper section of the joint. As an example of the tensile strength a releasably coupling joint could withstand, a grab method test (according to ISO 13934- 2:2014) was performed on the upper section, 5 cm wide and 4cm long, yielding the following results: the warp direction (length) reached a breaking force of 424.3 N, and the weft direction (width) reached a breaking force of 365.5 N. These values represent the maximum tensile forces the fabric could withstand before failure under the test conditions. However, it is important to note that the actual tensile strength required for the coupling joint will vary based on a number of factors, including but not limited to the material used, the size of the bags, the operation of the unwinding machine, and the type of product contained in the bags. Consequently, while these values serve as an example, they are not to be seen as limiting, as a person skilled in the art will understand the need to adjust material selections and joint configurations based on the specific requirements of each application.

[0091] The lower section of the releasably coupling joint is formed by at least one strip of fabric made of a different material as the woven textile of the bag. For example, a non-woven polypropylene. This different material has a tensile strength capable of withstanding a predetermined tensile force applied by the bag-filling machine upon unwinding the serial assembly. In such a manner the connection between the successive bags will not be broken by the tensile force applied by the bagfilling machine upon unwinding.

[0092] The example shows a serial assembly of two connected bags, but this number is not limitative. It is possible to add as many bags as desired to the assembly through releasably coupling oints .

[0093] While the joints are here depicted as having two longitudinal strips assembled together after manufacture of the bag to form the final strip, this is one possible embodiment . Indeed, another manufacturing process of the bag assembly can provide direct insertion of a fabric strip connecting the two bags at the step of forming the bag, or can connect the bags after manufacture of the bag, by sewing, gluing, stitching, ... on each lateral edge of the bags one strip or several strip sections . .

[0094] Referring to Figures 4 , a serial assembly of two connected bags 810 and 820 made of a woven textile material having a releasably coupling j oint 815 extending between the open top of one bag 810 and the closed bottom of the other subsequent bag 820 . The j oint is preferably mechanically fastened to each bag .

[0095] In this example , each bag 810 and 820 comprises an open top 813 and 823 respectively, a closed bottom 814 and 824 , two faces and two lateral edges 811and 812 , 821and 822 respectively . The two faces of the bag are connected from bottom 824 towards the top 813 . The lateral edges at which the two faces connect are two side seams 811 , 812 , 821 , 822 . The closed bottom of the bag 814 ; 824 is preferably a seam .

[0096] Figure 5 is a side view of an example of implementation of the strip 815 depicted on figure 4 . For example , strip 815 can comprise two strips of fabric 8151 and 8152 sewn along the top edges 91 and 92 of each face of each bag 810 in the assembly and a strip of fabric 825 inserted and sewn into the seam of the bottom of bag 820 . The connection between the two bags 810 and 820 , is made by sewing the strip of fabric 825 to the two strips of fabric 8151 and 8152 sewn to the top edge of the bag 810 . This connection forms a set of two vertically connected bags 810 and 820 that can be used in an automatic filling machine . The process requires to cut the releasably coupling j oint at the level of the strips of fabric 8151 and 8152 so that the bag 810 can be opened after cutting .

[0097] The serial assembly of connected bags can be arranged in various ways depending on the machine used to fill the bags . For example , Figure 6 shows a top view of an arrangement in the form of a roll around a hollow cylinder 42 . The bags 41 are wrapped around the cylinder 42 . This arrangement is suitable for many machines known for use for the automatic filling of plastic bags .

[0098] Another example of a serial assembly arrangement is illustrated in Figure 7 by a side view . The serial assembly of at least two or more adj acent bags 51 are arranged in accordion configuration and can potentially feed a machine adapted to this arrangement .

[0099] Figure 8 illustrates a method of filling a serial assembly of three connected bags connected along their lateral edge , as shown in Figure 9 , with a machine similar or equivalent to the machine named NETAUTOMAAT produced by De Bruyne NV in Belgium . This machine was originally produced for the purpose of packing potatoes in plastic nets . However, the present assembly o f three bags 110 , 120 and 140 connected by their lateral edges , of fers the possibility of replacing plastic with a woven textile that is preferably compostable and / or reusable .

[0100] The method for the present example comprises the fol lowing steps . During the first step 1 , the serial assembly o f connected bags , in the form of a roll around a hollow cylinder, is positioned vertically on a circular tray . The translation movements of the roll of bags are blocked by a sleeve inserted in the centre of the cylinder . What remains is a rotational movement that can be partially controlled by adj usting the tightening between the sleeve and the cylinder . The greater the tightening, the greater the tensile force required to unwind the bags . The diameter of the tray determines the number of bags the roller can hold . For ease of understanding, the following steps are described in terms of the progress of one bag 110 of the assembly shown in Figure 7 . The arrow 71 represents the direction of travel of the bags during the process .

[0101] During the second step 2 , the bag passes through an interlacing of vertical rollers . These rollers are mobile when the machine is running and generate tensile stress on all the bags . Thi s tensile stress is necessary for two main reasons . Firstly, it ensures that there is no play in the unrolled bags and that they are therefore in the exact position required by the method . The following steps j usti fy this need for positioning accuracy . Secondly, tensile stress is required to unwind the roll , which is braked by the sleeve .

[0102] During the third step 3 , the top edge of the bag 110 enters the space between the rails that allow the bag 110 to be guided by the rails . In other words , after passing the rollers in the previous step, the bag 110 , and more speci fically its top edge , enters the space between the rail s , the purpose of which is to guide the bag while travelling and move it forward during the subsequent steps in the method .

[0103] During the fourth step 4 , the lower section 115 ; 125 of the releasably coupling j oint 115 ; 116 ; 125 ; 126 , extending upwards from the bottom, which connect the bag 110 and the bag 120 preceding it , is cut . This lower section 115 ; 125 is cut in order to anticipate the bag 110 filling step, which can create tensile stress at the bottom of the bag 110. Consequently, separating the lower section 115; 125 considerably reduces this tensile stress. Separation is preferably achieved by thermal cutting of the releasably coupling joint. However, this machine station is a removable module. It is therefore possible to modify this module to perform a mechanical cut using a cutting blade. The joint 115; 116; 125; 126 is not completely cut because the bag 110 must continue to advance through its connection with the other bags. The remaining section 116; 126 must therefore be strong enough to withstand the tensile force transmitted from one bag to another. At the end of this fourth step, the bag 110 is partially connected to the bag 120 preceding it, fully connected to the bag 140 succeeding it, and advances through the rails to the next step.

[0104] During the fifth step 5, the lower section 1150; 135 of the joint 1150; 1160; 135 : 136, which connect the bag 110 and the bag succeeding it 140, are cut. The purpose of this step is similar to that of the previous step. At the end of this step, the bag 110 is partially connected to the preceding and succeeding bags 120; 140 and advances through the rails to the next step.

[0105] During the sixth step 6, the top 113 of the bag 110 is opened in preparation for the filling step. As the bag 110 moves forward, two pins, preferably made of metal, penetrate the open top 113, which is initially narrow because the bag 110 is first flattened. When the bag 110 stops, the pins move apart to widen the open top 113.

[0106] During the seventh step 7, the bag 110 is filled with a predetermined amount of product. The NETAUTOMAAT machine is specially designed for potatoes and onions, products for which 1 jute fabric is advantageous for conservation reasons. The product is conveyed to the top of the bag 110, weighed and poured into the bag to fill it. Among other things, weighing ensures that the quantity of product per bag announced by the producer / seller is respected and that the quantity poured is adjusted according to the size of the bag. From the filling station, a conveyor belt runs beneath the bag 110. When the bag 110 is filled, it spread open under the weight of its contents and comes into contact with the conveyor belt below it. This conveyor belt reduces the tensile stress undergone by the upper section of the bag in the guide means / rails. The conveyor belt also assists the bag as it advances to the next stages .

[0107] During the eight step 8, the bag 110 is closed using a sewing station. As it moves forward, the bag is sewn along its entire length by an automatic sewing machine, which engages as the bag passes through it. At the exit of this station, the bag 110 is filled, closed by a seam, connected to the assembly by the upper section of its joint, extending downwards from the top along the lateral edge, and advances on a conveyor belt towards the next step.

[0108] During the ninth step 9, the upper section 116; 126 of the joint 115; 116; 125; 126, which connect the bag 110 and the bag 120 preceding it, is cut. This separation is preferably achieved by thermal cutting of the joint. However, this machine station is a removable module. It is therefore possible to modify this module to perform a mechanical cut using a cutting blade. At the end of this step, the bag 110 is connected only to the bag succeeding 140 it by the upper section 136; 1160 of the joint and moves on to the last step. During the tenth step 10, the upper section 136; 1160 of the releasably coupling joint 1150; 1160; 135; 136, which connect the bag 110 and the bag 140 succeeding it, is cut. In this way, the bag 110 is completely disconnected from the assembly of bags. The top edge of the bag comes off the rail, the bag continues to move forward on the conveyor belt and falls, for example, into a trolley.

[0109] A person skilled in the art will understand that some of the steps described above are purely linked to a specific machinery and would optional or performed differently on a different working station.

[0110] Though the assembly of bags of the present invention has been designed to be usable on machines existing for handling plastic bags, it is obvious that new machines better suited for handling textile bags will be developed and be suitable for handling the assembly of bags of the present invention.

Claims

Claims1. A serial assembly (100; 101) of connected bags for feeding an automatic bag-filling machine, said bags being made of textile, characterized in that each pair of two consecutive bags of the serial assembly is connected by a releasably coupling joint (115; 825) disposed between two consecutive bags (110; 810;120; 820) , and wherein the releasably coupling joint is formed by at least one strip of fabric made of a different material as the textile of the bag and having a tensile strength capable of withstanding a predetermined tensile force applied by the bag-filling machine upon unwinding the serial assembly.

2. The serial assembly of connected bags according to claim 1, wherein the releasable coupling joint is dimensioned to separate or otherwise space-out two consecutive bags over a distance extending from 0.5 to 10 cm, preferably from 0.7 and 5 cm.

3. The serial assembly of connected bags according to claim 1 or 2, wherein each bag (110; 120) comprises an open top (113;123) , a closed bottom ( 114 ; 124 ) , two faces and two lateral edges ( 111 ; 112 ; 121 ; 122 ) along which the two faces of the bag connect from bottom (114;124) towards the top (113;123) , and wherein the lateral edges at which the two faces connect comprise corresponding side seams ( 111 ; 112 ; 121 ; 122 ) .

4. The serial assembly of connected bags according to claim 3, wherein the releasably coupling joint (115) comprises a lower section extending from bottom towards the top along the lateral edges of the bags.

5. The serial assembly of connected bags according to claim 3, wherein the releasable coupling joint ( 115 ; 116 ; 125 ; 126 ) comprises two sections, the lower section (115; 125) extending upwards from the bottom and an upper section (116; 126) extending downwards from the top.

6. The serial assembly of connected bags according to claim 5, wherein the connection between the two faces of each bag at the lateral edges does not extend over the full height of the bag thereby leaving an aperture (130) between two consecutive bags, and wherein the upper section of the joint, extending downwards from the top, comprises two parallel strips of fabric each connecting a face of a bag to a corresponding face of the consecutive bag without obstructing the aperture (130) .

7. The serial assembly of connected bags according to any of the preceding claims, wherein the joint (115; 825) is made of a fabric comprising polypropylene, preferably non-woven polypropylene .

8. The serial assembly of connected bags according to any of the preceding claims wherein each bag further comprises handles (117; 127) .

9. The serial assembly of connected bags according to claim 8, wherein the handles consist of an added further strip of fabric sewn or otherwise mechanically fastened to the open top of the bag, said added strip of fabric being the open top of the bag.

10. The serial assembly of connected bags according to any of the preceding claims, wherein the textile material is a wovenmaterial, preferably a natural woven material, more preferably a natural woven material made predominantly of jute.

11. The serial assembly of connected bags according to any of the preceding claims, wherein the releasably coupling joint has a tensile strength comprised between 1 and 50 MPA, preferably between 5 and 50 MPa, preferably between 10 and 50 MPa, preferably between 15 and 50 MPa, preferably between 20 and 50 MPa, preferably between 25 and 50 MPa, preferably between 30 and 50 MPa, preferably between 35 and 50 MPa and preferably between 40 and 50 MPa.

12. A method for feeding an automatic bag-filling machine with a serial assembly of connected bags according to any of claims 4 to 11 and for filling the bags with a product, comprising:- positioning (1) the serial assembly of connected bags at the input of a bag loading equipment;- inserting (2) the top border of a bag of the serial assembly into a guide means;- moving (3) the bag towards a loading station, thereby - pulling the consecutive bag so that its top border is inserted into the guide means,- widening (6) an open top of the bag, filling (7) the bag with a predetermined amount of product,- cutting at least part of the releasable coupling joint, and, and- repeating the above steps for the consecutive bags.

13. The method of claim 12 further comprising:- closing the open top of the bags.

14. The method according to one of claims 12 and 13, wherein cutting (5) the releasably coupling joint is performed in at least two steps including cutting the lower section, extending upwards from the bottom, of the joint before filling the bag and cutting the upper section, extending downwards from the top, of the joint after filling the bag.

15. The method according to any of claims 12 to 14, wherein the cutting step comprises a thermal cutting of the releasably coupling joint.

16. The method according to any of claims 12 to 15, wherein the cutting step comprises a mechanical cutting of the releasably coupling joint.

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