METHOD AND DEVICE FOR CLOSING PACKAGES

Description

[0001] The invention relates to a device for sealing packages, comprising a product feed and a packaging material feed for a tubular packaging material. Such devices are used, for example, as tubular bag machines.

[0002] Furthermore, the invention relates to a method for closing packages.

[0003] According to the prior art, devices for closing packages, comprising a product feed and a packaging material feed for a tubular packaging material, are used, for example, to fill fruit or vegetables into net-like and / or tubular packaging materials and to close the packages. After the products to be packaged have been portioned, for example using a weighing device or a counting device, they are guided via the product feed into the area of ​​the tubular packaging material. The tubular packaging material is first closed at one end using a closing device, so that the product to be packaged is fed into the packaging tube, which is closed on one side.After a defined quantity of product has been filled, the packaging tube is also closed at the second end using a closing device and separated from the packaging stock using a separating device.

[0004] According to the state of the art, it has proven particularly advantageous to simultaneously close the second end of a first, already filled packaging tube and the first end of a second packaging tube in parallel in one production step.

[0005] High demands are placed on the strength of the packaging closures to ensure that the packaging does not open accidentally during subsequent handling. Particular attention must be paid to the relatively high weight of some products packaged in this form, such as potatoes or oranges.

[0006] According to the state of the art, sealing tape strips made of metal bands are generally used as closure elements. These strips are cut to length in the area of ​​the packaging sealing device and then bent around the ends of the packaging tube in the closure area in a clamp-like manner. Alternatively, packaging sealing devices are also known in which externally cut metal sealing tape strips are used.

[0007] In the wake of increased demands regarding environmental protection, another requirement for packaging is that it can be recycled as completely and easily as possible.

[0008] In addition to selecting recyclable materials for packaging, it is therefore advantageous to use as few different materials as possible. Ideally, packaging should consist of a single recyclable material and thus be homogeneous.

[0009] However, the net- and / or tube-like packaging closed using known devices has two metal clips arranged at each end of the packaging as closure elements, which have to be laboriously separated from the rest of the packaging when the packaging is recycled.

[0010] EP 3181 464 A1 already discloses a method and device for closing packages. A tubular packaging material is sealed in a closure area by a closure element. The package is bag-like and has a closed bottom and, before filling, an open mouth area. After filling, the mouth area is closed by pressing the mouth material together and welding it.

[0011] EP 1522497 A1 also discloses the sealing of a bag-like package with a closed bottom by pressing the two parts together and sliding a closure element onto the opening area. A sealing element can be used to achieve sufficient tightness.

[0012] EP 08 23376 A1 describes a tubular mesh bag packaging. The packaging is sealed with a metal strip by folding it over at the bottom before filling and at the mouth after filling.

[0013] EP 0960822 A1 describes the closure of a bag-like receiving element by means of a closure element that is placed around the opening area. The closure element can be secured by welding or gluing.

[0014] EP 0 887 271 A1 already discloses a device for packaging products. It has a heat-sealing element for closing a tubular package, with which the package can be melted in the closure area. Sealing the tubular package with heat seals completely eliminates the need for closure elements, even those made of a different material from the rest of the packaging, such as metal.However, disadvantages of the known devices and methods for closing tubular packaging material using heat-sealing elements are a lower load-bearing capacity of the sealing seam of the packaging compared to the use of a metal closure element, the more complex manufacture of corresponding devices for packaging products and closing the packaging and, due to the requirement to cool both the heat-sealing elements and the heat-sealing seams, extended packaging cycles.

[0015] An object of the invention is therefore to provide a device for closing packages which enables the packaging of products in a tubular packaging material and the closing of the tubular packages in an improved manner.

[0016] A further object of the invention is to provide a device for closing packages which enables the packaging of products in tubular packages and the closing of the tubular packages in such a way that the package has as few different materials as possible

[0017] These objects are achieved by a device for closing packages having the features according to patent claim 1.

[0018] A further object of the invention is to provide an improved method for closing packages, in which products are packaged in a tubular package and the tubular packages are closed.

[0019] A further object of the invention is to provide a method for closing packages, in which products are packaged in a tubular package and the packages are closed, wherein the packages comprise as few different materials as possible.

[0020] These objects are achieved by an inventive method for closing packages according to patent claim 7.

[0021] The features of the invention disclosed below are part of the invention both in all executable subcombinations and in the combination of all disclosed features. A device according to the invention for closing packages comprises at least one closure device with which at least one end of at least one tubular package can be closed in a closure region with a material fit.

[0022] A closed tubular packaging has at least two closure areas, of which a first closure area is arranged in the area of ​​the first end and a second closure area is arranged in the area of ​​the second end of the tubular packaging.

[0023] Such a packaging is designed, for example, as a mesh bag and has exactly two closure areas, each arranged at one end of the packaging.

[0024] By means of a device for closing packages, in one embodiment according to the invention a tubular package can be closed in at least one closure region with a closure element designed as a closure tape strip.

[0025] In a preferred embodiment of the invention, a tubular packaging can be closed with a closure tape strip made of the same material as the rest of the packaging, so that single-variety packaging can be produced.

[0026] The packaging material is usually a thermally meltable or weldable plastic.

[0027] In one embodiment of the invention, the device for closing packages comprises a transport device for at least one closure tape and / or one closure tape strip.

[0028] In a preferred embodiment of the invention, the transport device has at least one drive roller, particularly preferably two drive rollers.

[0029] In one embodiment of the invention, it has a cutting device with which a fastener tape can be cut into fastener tape strips of a defined length.

[0030] In one embodiment of the invention, it comprises a forming device with which a fastener tape strip can be formed.

[0031] In a preferred embodiment of the invention, the fastener tape strip can be formed into a U-shape using the forming device.

[0032] In one embodiment of the invention, the forming device comprises a slider, designed, for example, as a bending bolt, and a die with a U-shaped contour, wherein the fastener tape strip can be pushed by the slider into the die with a U-shaped contour and can thereby be formed into a U-shape.

[0033] In a further embodiment of the invention, the device for closing packages comprises a bending device with which at least one closure tape strip can be bent around at least one end of a package, so that a package can be enclosed in each closure region by means of at least one closure tape strip.

[0034] In a preferred embodiment of a device according to the invention for closing packages, said device has a closing device designed as a welding device for closing packages with a closing tape made of the same material, with which at least one closing tape strip can be welded to the material of at least one package.

[0035] In a particularly preferred embodiment of a device for closing according to the invention, the welding device is designed as an ultrasonic welding device.

[0036] The use of an ultrasonic welding device enables an improved production cycle compared to conventional welding devices or heat-sealing elements, since the temperature required to produce the weld is essentially only generated in the area of ​​the weld and the surrounding elements of the device for closing packaging do not heat up unnecessarily, meaning that they no longer need to be cooled after each production cycle.

[0037] In a preferred embodiment, the ultrasonic welding device is designed as an ultrasonic sonotrode.

[0038] In a further embodiment of the invention, a device for closing packaging has at least one ultrasonic welding device with which two weld seams can be produced simultaneously.

[0039] In a particularly preferred embodiment of the invention, it has a U-shaped ultrasonic sonotrode, wherein ultrasonic welds can be produced in the two end regions of the U-shaped ultrasonic sonotrode.

[0040] In a further embodiment of the invention, the closure device comprises an adhesive device for the integral bonding of the closure tape strip and the packaging. The adhesive device allows the closure tape strip and the packaging to be adhesively bonded to one another.

[0041] In a further preferred embodiment of a device according to the invention for closing packages, the device comprises at least one cooling device with which the at least one closure region can be cooled after the connection of at least one package and at least one closure strip. Cooling the weld seam after the welding of the closure strip and the package allows the weld seam to be subjected to stress after a short time, thus enabling an increased production rate.

[0042] In a preferred embodiment of the invention, the cooling device is designed as a cold air supply.

[0043] To secure the packaging and relieve stress on the weld seam in a hot state, a device according to the invention for closing packaging, in one embodiment, comprises at least one clamping device, with the aid of which a tubular packaging or the packaging tube can be clamped on at least one side adjacent to the area of ​​a weld seam to be produced, i.e., adjacent to the closure area. This allows the weld seam to be relieved of stress, particularly in a hot state, so that undesirable deformation of the material due to force effects, in particular due to the weight of the possibly filled packaging, can be effectively avoided.

[0044] In one embodiment of the invention, it has two clamping devices, wherein a first package can be clamped adjacent to a closure area with the first clamping device and a second package can be clamped adjacent to a closure area with the second clamping device.

[0045] In one embodiment of the invention, this comprises a separating device with which the packaging tube can be severed so that sealed packages can be separated from the packaging stock.

[0046] In a preferred embodiment of the invention, the separating device is designed as a cutting tool.

[0047] In a particularly preferred embodiment of the invention, it is designed for the simultaneous production of two weld seams, one weld seam each on a package, wherein the two packages can be separated from one another between the weld seams using the separating device.

[0048] In one embodiment of the invention, this comprises a packaging material feed via which the tubular packaging material can be fed from the packaging material supply into the area of ​​the closure device.

[0049] In one embodiment of the invention, the latter comprises a packaging material storage device with which tubular packaging material can be stored in the region of the device for closing packages.

[0050] In a preferred embodiment of the invention, the packaging material storage device is designed as at least one tube onto which the tubular packaging material is pushed and which thus represents the packaging material supply.

[0051] The design of the packaging material storage device as a tube also enables the tubular packaging to be filled through the tube.

[0052] In one embodiment of the invention, this has at least one product feed through which the products to be packaged can be filled into the tubular packaging.

[0053] In a further embodiment of the invention, it has at least one weighing device for portioning the products to be filled and packaged.

[0054] In one embodiment of the invention, it is designed to close packaging nets.

[0055] In particular, the packaging material and the material of the closure tape or the closure elements designed as closure tape strips are intended to be made of recyclable plastics, such as polyethylene and HDPE, or of biodegradable and thermally weldable materials, such as starch or cellulose.

[0056] By combining at least one ultrasonic welding device and the use of closure elements designed as closure tape strips made of the same material as the rest of the packaging, a preferred embodiment of a device according to the invention for closing packaging makes it possible to produce single-variety tubular packaging with a high load-bearing capacity of the weld seams or closures.

[0057] A method according to the invention for closing packages comprises, as one method step, a closure region of a package is enclosed with a closure tape strip and, as a further method step, the closure tape strip is connected to the package by welding and / or gluing.

[0058] In a preferred embodiment of the method according to the invention for closing packages, ultrasonic welding is carried out between the closure element designed as a closure tape strip and the package.

[0059] In a further embodiment of a method according to the invention for closing packages, at least one closure tape strip is produced from at least one closure tape by cutting to length in a sequence of method steps, and the at least one closure tape strip is bent around the package.

[0060] In a particularly preferred embodiment of a method according to the invention for closing packages, a device according to the invention for closing packages is used.

[0061] In a further embodiment of the invention, the method for closing packages comprises the following method steps: Clamping the tubular packaging adjacent to the closure area with a clamping device Bending the closure tape strip around the tubular packaging in the closure area Ultrasonic welding of the closure tape strip to the tubular packaging in the closure area Cooling the closure area using a cooling device Separating the tubular packaging from the packaging material supply using a separating device

[0062] In an embodiment of the method for closing packaging according to the invention, the tubular packaging is filled with a product in a further method step.

[0063] In a further embodiment of the method for closing products according to the invention, the closure tape strip is provided by the following method steps: Transporting the fastener tape using a transport device Cutting a fastener tape to a fastener tape strip using a cutting device Shaping the fastener tape strip into a U-shape using a forming device

[0064] The transport of the fastener tape includes, for example, unrolling the fastener tape from a fastener tape roll and feeding the fastener tape into the area of ​​a cutting device for cutting the fastener tape to length using a transport device.

[0065] The order of the method steps disclosed above is not always determined by the order listed. In particular, several similar or different method steps can be carried out in parallel.

[0066] For example, several closure elements designed as closure band stiffeners can be produced simultaneously and / or several closure elements can be welded to one or more packages at the same time.

[0067] In particular, the simultaneous clamping of at least one package and the welding of at least one package with a closure element are also considered.

[0068] Furthermore, a component of the invention is a packaging comprising a tubular body which is designed to be filled with pourable products, wherein the packaging is closed in the region of both ends with at least one closure element, characterized in that it is a single-variety packaging made of a thermally fusible plastic or starch or cellulose, wherein the closure elements are connected to the packaging in each closure region by thermal welding.

[0069] The terms "tubular" and / or "net-like" used are to be interpreted broadly and generally understood to mean that the packaging has a tube-like design, at least in sections. The wall material can be closed or formed with recesses, which in particular allows for a net-like shape. However, due to the flexibility of the wall material, the shape of the packaging is not stable, like a bag or sack.

[0070] The invention recognizes that, due to the superimposed layers of packaging material created in the closure area by compressing the packaging, sufficient load-bearing capacity of the hardened weld seams cannot be achieved within a reasonable amount of time by exclusively ultrasonic welding of the layers of the packaging in the closure area, since not all layers of the packaging material may be firmly welded together.

[0071] Particularly with mesh-like packaging, individual outer threads of the packaging may become detached from the welded seam, thus reducing the strength of the packaging in the closure area. Furthermore, if threads become detached from the welded seam, a hole may form in the packaging, through which products could fall out.

[0072] This problem is solved according to the invention by the use of at least one closure element designed as a closure tape strip per closure area of ​​a package, wherein the closure tape strip additionally holds the packaging layers in the closure area in a force-fitting manner by bending around it after welding.

[0073] The following figures show exemplary embodiments of the device for closing packages according to the invention and the method for closing packages according to the invention. They show: Figure 1: A block diagram of an embodiment of a device according to the invention for closing packages, Figure 2: A perspective view of the closing area of ​​two tubular packages, Figure 3: A perspective view of a closure tape roll with subsequent transport device and part of a forming device, Figure 4: A perspective detailed view of a forming device for a closure tape strip during and after the insertion of the closure tape strip, Figure 5: A perspective detailed view of the closing area of ​​a package with the closure tape strip pushed on, and Figure 6: A cross section in the closing area of ​​a package, wherein the package is arranged in the area of ​​the welding device and the bending device of a device according to the invention for closing packages.

[0074] In Figure 1The block diagram of an exemplary embodiment of a device for closing packaging (1) according to the invention is shown. The device for closing packaging (1) has a packaging material storage device (2), a packaging material feed (3), and a product feed (4). With the aid of the packaging material feed (3), the tubular packaging material stored in the region of the packaging material storage device (2) can be fed to the devices of the device for closing packaging (1) designed for filling and closing the packaging.

[0075] Furthermore, the device for closing packages (1) comprises a clamping device (5) with which the packaging tube can be clamped and thus fixed. Furthermore, the device for closing packages (1) comprises a closure device (6) designed as a welding device, with which a package can be welded or fused in a closure region to a closure element designed as a closure tape strip.

[0076] The device for closing packages (1) further comprises a closure tape supply (8), from which the closure tape can be transported by means of a transport device (9) into the area of ​​a cutting device (10). By means of the cutting device (10), the closure tape can be cut into closure tape strips of defined length. By means of a forming device (11), the closure tape strip can be formed into a U-shape. The closure tape strip pushed over the package in the closure area can be bent around the package by means of a bending device (12) and then welded to the package by means of the closing device (6) designed as a welding device. To increase the production cycle, the device for closing packages (1) further comprises a cooling device (13) with which the closure area can be cooled after the package and closure tape strip have been welded.

[0077] In addition, the device for closing packages (1) has a separating device (7) with which filled and / or closed packages can be separated from the packaging material tube of the packaging material supply.

[0078] Figure 2 shows a perspective view of the closure region (22) of two tubular packages (20) comprising a tubular packaging means (21) designed as a net. In the closure region (22), the packages (20) are enclosed by a closure element (23) designed as a closure tape strip, which is welded or fused to the package (20).

[0079] In Figure 3A perspective view of a fastener tape supply (8) configured as a fastener tape roll with an adjoining transport device (9) and a portion of the forming device (11) is shown. Using the transport device (9), the fastener tape can be unrolled from the fastener tape roll and transported into the area of ​​the cutting device (10) (not shown) and the forming device (11). The fastener element (23), which is separated from the fastener tape by means of the cutting device (10) and configured as a fastener tape strip, can be formed using the slider (11a) of the forming device (11).

[0080] Figure 4shows a perspective detailed view of a forming device (11) for a closure element (23) designed as a fastener tape strip. In the left-hand area of ​​the figure, this shows the closure tape strip being pushed into a die (11b) using the slider (11a), and in the right-hand area, this shows the closure tape strip being pushed into the die (11b). The die (11b) of the forming device (11) has two rectangular recesses, into each of which a fastener tape strip can be pushed and formed into a U using a slider (11a) designed as a bending bolt. The die (11b) shown is designed for the simultaneous forming of two fastener tape strips.

[0081] In Figure 5 a perspective detailed view of the closure area (22) of a package (20) with a pushed-on, U-shaped closure element (23) designed as a closure tape strip is shown.

[0082] Figure 6shows a cross-section in the closure region (22) of a package (20). The package (20) is arranged in the region of the closure device (6), designed as an ultrasonic welding device, and the bending device (12) of an inventive device for closing packages (1). The closure element (23), designed as a closure tape strip, is bent around the package (20) in the closure region (22). The closure tape strip can be bent around the package (20) with the aid of the bending device (12) by being pressed against the end face of the closure device (6), designed as an ultrasonic welding device, with the aid of the bending device (12). To assist in wrapping the closure tape strip around the package (20), the end face of the ultrasonic welding device (6) in the illustrated embodiment of an inventive device for closing packages (1) is rounded in a U-shape.

[0083] Drive elements used in the device can, for example, be designed as pneumatic piston-cylinder arrangements. Alternatively or additionally, it is also conceivable to implement some or all of the drives as electric motors. Preferably, the corresponding electric drives are designed as stepper motors. Such stepper motors support very precise movement to a preselected position and thus a very high degree of repeatability when executing movements.

[0084] The aforementioned drives can be used, for example, for positioning the clamping device (5). Other possible applications include positioning the closing device (6) and / or the cutting device (10) and / or the forming device (11). Corresponding drives can also be used for the weighing device (12) and / or the separating device (7) and / or the forming device (11) and / or the ultrasonic welding device (6).

Claims

1. Device for closing packages (1), having a product feed unit (4) and a packaging material feed unit (3) for a tubular packaging material and a transport device (9) for at least one sealing tape and / or sealing elements (23) in the form of sealing strips, the device (1) having a sealing device (6) with which at least one package (20) can be enclosed in at least one sealing region (22) by a sealing element (23) formed as a sealing strip and with which a materially bonded connection of the sealing strip to the package (20) can be produced, wherein the sealing device (6) has a welding device for realizing the materially bonded connection of sealing elements (23) formed as sealing strips to the package (20) and wherein the sealing elements (23) are made from the same material as the tubular packaging material, characterized in that the sealing device has a bending device (12), with which at least one sealing strip can be bent around at least one end of the package (20), so that the package (20) can be enclosed in a sealing region (22) respectively with the aid of at least one sealing strip, and in that it has at least one clamping device (5), with the aid of which a tubular package (20) or the packaging tube can be clamped on at least one side adjacent to the region of a weld seam to be produced, i.e. adjacent to the sealing region (22), in such a way that the weld seam can be relieved, in particular in a hot state, and in that it has a cooling device (13) with which the region of the connection of a package (20) with at least one sealing element (23) in the form of a sealing strip can be cooled.

2. Device (1) according to claim 1, characterized in that it comprises a forming device (11), with which a sealing strip can be formed into a U-shape.

3. Device (1) according to one of the preceding claims, characterized in that the welding device is designed as an ultrasonic welding device.

4. Device (1) according to claim 3, characterized in that the welding device has a U-shaped ultrasonic sonotrode, wherein ultrasonic welds are being producible in the two end regions of the U-shaped ultrasonic sonotrode, so that two weld seams can be produced simultaneously.

5. Device (1) according to claim 1, characterized in that the sealing device (6) has an adhesive device for realizing the materially bonded connection of sealing elements (23) in the form of sealing strips to the package.

6. Device (1) according to at least one of the preceding claims, characterized in that it is designed for closing packaging nets.

7. Device (1) according to at least one of the preceding claims, characterized in that it is designed for closing packages (20) with sealing elements (23) made of the same material as the package (20), so that packages (20) of a single material can be produced.

8. Method for closing packages, in which in a method step one end of a package (20) is enclosed by a sealing element (23) designed as a sealing strip and in that in a further method step the sealing strip is connected to the package (20) by welding, wherein at least one sealing strip is being produced from at least one sealing tape by cutting to length in a sequence of method steps and the at least one sealing strip is bent around the tubular package (20) in a sealing region (22) and that the same material is used for the sealing strip as for the tubular packaging, characterized in that the tubular packaging (20) is clamped on at least one side adjacent to the region of a weld seam to be produced, i.e. adjacent to the sealing region (22), by means of at least one clamping device (5) in such a way that the weld seam is relieved, particularly in a hot state.

9. Method according to claim 8, characterized in that an ultrasonic welding of the sealing strip and packaging (20) is carried out.

10. Method according to one of claims 8 and 9, characterized in that the tubular packaging (20) is welded simultaneously in both end areas.

11. Method according to at least one of claims 8 to 10, characterized in that for closing the package (20) a device (1) according to one of the claims 1 to 7 is used.