Core replacement adapter for coreless film rolls

Abstract

Adapter (100) for use in unwinding film from coreless film rolls (200), which has a roll passage with a first and a second opening (210) at opposite ends of the coreless film roll (200), wherein the adapter (100) comprises: a longitudinally extended adapter element (10), wherein the adapter element (10) has at a first free end a projecting head section (13) with an adapter ring (11) as a stop for the film roll (200), and wherein the adapter element (10) has on the lateral surface (12), which extends between the adapter ring (11) and a second free end, at least two first longitudinally extended clamping elements (15) and at least two second longitudinally extended clamping elements (16) for clamping the adapter element (10) in the roll passage, which are fixed on the lateral surface (12) and protrude from the lateral surface (12), wherein the at least two first longitudinally extended clamping elements (15) are arranged in a first region (17) of the lateral surface (12) and the at least two second longitudinally extended clamping elements (16) are arranged in a second region (18) of the lateral surface (12), wherein the first region (17) and the second region (18) of the lateral surface (12) one after the other,are arranged with respect to the main axis of the adapter element (10), wherein the at least two first longitudinally extended clamping elements (15) and the at least two second longitudinally extended clamping elements (16) are each maximally spaced apart from each other and are arranged parallel to each other and to the main axis of the adapter element (10).

Description

[0001] The invention relates to an adapter for use in unwinding film from coreless film rolls, which has a roll passage with a first and a second opening at opposite ends of the coreless film roll.

[0002] Stretch film is a thin, elastic plastic film used to wrap and secure objects. It is frequently used in logistics for securing loads. Stretch film adheres to the packaged objects without additional aids due to its inherent adhesiveness (cling) combined with its elasticity and the pressure applied during wrapping.

[0003] In the conventional and prestretch manufacturing process, these films are wound onto cardboard or plastic cores, i.e., cardboard or plastic tubes. The stretch films are delivered by the film manufacturer wound onto the cardboard or plastic core, ready to be unwound directly from it for packaging the goods.

[0004] To avoid waste and reduce the weight of the film roll, coreless rolls are commonly manufactured. Since there is no core, there is no need to dispose of it after the film is used up. This reduces waste and contributes to sustainability. Coreless film rolls are a special type of stretch film roll that lacks the usual cardboard or plastic core in the middle. Instead, the roll consists only of the stretch film itself, which is wound directly onto the film using a special winding technique. They are available in various thicknesses and sizes and can be used in various industries where stretch film is used for securing loads.

[0005] Eliminating cardboard cores also results in savings, as these roll cores account for approximately 5% of the cost of each roll of film.

[0006] Furthermore, coreless film rolls offer other advantages. They are generally lighter and more compact than conventional rolls, making transport and storage easier. They are also easier to mount on a dispenser, as there is no core that sometimes needs to be removed or replaced. Coreless film rolls offer more film per roll for the same weight.

[0007] Since coreless rolls are not wound on a cardboard or plastic core, a dispensing aid (adapter) is required to unwind the film roll. These adapters are reusable as often as needed.

[0008] There are various types of stretch film dispensers, including manual dispensers where the film is unwound by hand and automatic dispensers where the film is unwound by a stretch wrapping or wrapping machine. Both types of dispensers ensure even and tight wrapping of the goods being packaged. They simplify the packaging process and ensure efficient and secure packaging. The choice of the appropriate dispenser depends on individual requirements and the packaging volume.

[0009] Mechanical stretch wrapping machines are primarily used where large quantities of products need to be packaged. They offer a number of advantages, including faster and more efficient packaging, even and tight wrapping of the film, and the elimination of physical strain on employees.

[0010] Various adapters for coreless film rolls for manual dispensers are known from the state of the art.

[0011] US 2011 / 0041458 A1 describes an adapter consisting of 2 parts, both parts being connected to each other via a threaded system and being continuously adjustable in length.

[0012] There are only a few adapters available for using coreless film rolls with machine stretch wrapping machines. For example, US 10,308,474 B2 describes an adapter that is intended for both hand and machine stretch wrapping applications. This adapter consists of two interlocking adapter parts with rigid, wedge-shaped elements located along the longitudinal axis of the adapter.

[0013] DE 20 2023 106 929 U1 describes an adapter for use in unwinding film from coreless rolls, wherein the adapter consists of two connectable adapter elements, and wherein the adapter elements can each have several clamping elements.

[0014] The adapters that currently exist consist of at least two adapter parts that must be connected to each other before they can be used.

[0015] The object of the invention is to provide an adapter for coreless film rolls that enables easier handling compared to known adapter rolls and is simultaneously suitable for processing coreless film rolls, whereby the film roll is unwound evenly and with consistent quality to the end of the roll, even at high unwinding speeds.

[0016] The problem is solved by an adapter having the features of claim 1. Advantageous embodiments are characterized in the dependent claims.

[0017] According to the invention, an adapter is provided for use in unwinding film from coreless film rolls, which has a roll passage with a first and a second opening at opposite ends of the coreless film roll, comprising a longitudinally extended adapter element which has a projecting head part with an adapter ring as a stop for the film roll at a first free end, and which has at least two first longitudinally extended clamping elements and at least two second longitudinally extended clamping elements for clamping the adapter element in the roll passage of the film roll on a lateral surface extending between the adapter ring and a second free end, which are fixed on the lateral surface and protrude from the lateral surface.

[0018] The at least two first longitudinally extended clamping elements are arranged in a first region of the cylindrical surface and the at least two second longitudinally extended clamping elements are arranged in a second region of the cylindrical surface, wherein the first region and the second region of the cylindrical surface are arranged successively with respect to the principal axis of the adapter element, and wherein the at least two first longitudinally extended clamping elements and the at least two second longitudinally extended clamping elements are each maximally spaced apart from each other and are arranged parallel to each other and to the principal axis of the adapter element.

[0019] In addition to the at least two longitudinally extending clamping elements, the adapter has a second longitudinally extending adapter element, so that a relatively large area of ​​the inside of the film roll is advantageously engaged by the clamping elements for secure hold. Besides clamping the adapter element, the clamping elements also advantageously prevent the film roll from rotating on the adapter element.

[0020] The adapter design according to the invention makes it possible to process coreless film rolls with reduced assembly effort, since the adapter only needs to be inserted into the through-hole of the film roll from one side. Furthermore, the arrangement of the longitudinally extended clamping elements in two groups of at least two clamping elements each, one behind the other, on the outer surface of the film roll advantageously ensures that the film roll is tensioned evenly and thus held securely along its entire length. This allows the remainder of the film roll to be unwound evenly and with consistent quality to the end of the roll, even at high unwinding speeds, particularly when the film is nearly used up.

[0021] The projecting head section with an adapter ring that causes the projection, acting as a stop for the film roll, advantageously prevents the adapter element from slipping into the film roll and also ensures a correct fit of the adapter element.

[0022] The lateral surface of the adapter element extends between the adapter ring at the first free end as the head part of the adapter element and the outer edge of the second free end as the foot part of the adapter element.

[0023] Preferably, the outer surface of the adapter, or the adapter itself, has a cylindrical shape, although conical sections may also be present, preferably in the head section, with these sections tapering from the head towards the foot. The foot section may also be conical to facilitate easier insertion of the adapter into the film rolls.

[0024] The first and second clamping elements preferably arch over the lateral surface, preferably in the form of a circular segment or a shape derived therefrom.

[0025] The first and second longitudinally extended clamping elements for clamping the adapter element in the roller passage are fixed or reversible, preferably reversibly, arranged on the adapter element.

[0026] According to a particularly preferred embodiment of the adapter, the first and second clamping elements are each inserted with their free ends into openings or through-holes in the outer surface and are held there by their residual tension.

[0027] The free ends of the first and second clamping elements are preferably flattened in the direction of the openings / through openings, meaning that they are straight at the free ends to allow them to be easily inserted into the openings or through openings.

[0028] For the non-reversible arrangement of the at least two first and second clamping elements on the lateral surface, these are preferably glued in with at least one free end in the respective openings or through-holes.

[0029] In the preferred reversible arrangement of the at least two first and second clamping elements, these are preferably, as already described, arranged with their free ends in the respective openings or through-holes and are simply inserted. In a preferred embodiment of this variant, at least one through-hole is provided for securing each first or second clamping element, wherein a screw for clamping or fixing the first or second longitudinally extended clamping element is inserted from the side of the through-hole opposite the side from which the respective clamping element is inserted, such that its head is operable, while the other end of the screw acts on the end of the respective clamping element located in the through-hole.

[0030] The respective through-openings run parallel to the main axis of the adapter and open onto the end faces of the head and foot sections, from where the screw heads are easily accessible and the tension of the clamping elements can be adjusted.

[0031] In the area of ​​the first and second clamping elements, there is preferably a flattened surface on the adapter element below the clamping elements, which is referred to as the clamping element receiving area.

[0032] This area advantageously ensures that openings / passages are easily accessible, particularly when they run parallel to the main axis. Furthermore, in the case of non-circular roll geometries, this area provides space for the film.

[0033] The first and second clamping elements are preferably made of wire, preferably of metal or polymer, wherein the materials used preferably exhibit spring elasticity in order to maintain the tension necessary to hold the film roll. A particularly preferred material is therefore spring steel, for example in the form of curved bending springs.

[0034] The wire is preferably designed as a round wire, flat wire or profile wire, preferably as a round wire, in order to keep the design effort for the application with the adapter element as low as possible.

[0035] Apart from the first and second clamping elements, including the screws, the adapter is preferably made of plastic.

[0036] The at least two first and second longitudinally extended clamping elements preferably have a length of 1 / 10 to 2 / 5, particularly preferably 3 / 10 to 3 / 5 of the length of the adapter.

[0037] The adapter preferably has 4 or 6, particularly preferably 4 first and 4 second longitudinally extended clamping elements.

[0038] According to a particular embodiment of the adapter according to the invention, the at least two first longitudinally extended clamping elements and the at least two second longitudinally extended clamping elements are jointly designed as at least two third longitudinally extended clamping elements.

[0039] The other statements regarding the first and second longitudinally extended clamping elements apply equally to the third clamping elements.

[0040] According to a particularly preferred embodiment, the adapter has clamping elements and grooves.

[0041] According to a preferred embodiment of the adapter, at least two first longitudinally extended grooves are arranged on the lateral surface, which are maximally spaced apart from each other and are arranged parallel to each other and to the main axis of the adapter element.

[0042] These grooves are for use with special film rolls, in which, corresponding to the grooves, there are manufacturing-related film geometries (protrusions) in the roll passage that engage in the grooves.

[0043] The first two grooves can extend across the entire surface of the outer casing or the entire adapter element. However, it is also possible that the first two grooves extend only across a portion of the outer casing.

[0044] According to the invention, it is also provided that each of the at least two first longitudinally extended grooves is followed by a second longitudinally extended groove in the same orientation.

[0045] These second longitudinal grooves can be arranged in such a way that they transition directly into the respective first longitudinal groove, thus forming a continuous groove.

[0046] The at least two first longitudinally extended clamping elements are preferably arranged between the at least two first longitudinally extended grooves.

[0047] The grooves are preferably arranged centrally between the longitudinally extended clamping elements.

[0048] Preferably 4 or 6, particularly preferably 4 first longitudinally extending grooves are provided.

[0049] An embodiment with 8 longitudinally extending clamping elements and 4 grooves is most preferred, as this provides optimal support and prevents rotation during machine unwinding. Preferably, the clamping elements are arranged in two rows along the main axis, with two clamping elements on each axis parallel to the main axis and the two clamping elements spaced apart. The grooves are positioned centrally between the longitudinally extending clamping elements to ensure optimal effectiveness and easy manufacturing of the adapter elements.

[0050] The adapter element preferably has a cylindrical recess in the head section, coaxial with the main or longitudinal axis, which is designed to precisely accommodate a cone of a stretch wrapping machine.

[0051] According to an advantageous embodiment of the adapter element or the adapter itself, groove holes can be located at the ends of the grooves in the head of the adapter element. These groove holes at the ends of the grooves are formed by the passage of the grooves through the projecting head.

[0052] These grooves allow air to escape, which must be displaced from the roller guide between them and the film roll when inserting the adapter element. Furthermore, they facilitate easy removal of the adapter element from the film roll, as a tool can be inserted and secured into these grooves to serve as a pull handle.

[0053] The adapter according to the invention prevents damage to the film roll due to slippage and also makes it possible to use coreless stretch films in machine stretch applications that must meet higher requirements (e.g., unwinding speed).

[0054] The invention is explained in more detail below with the aid of figures. These show Fig. 1 in a perspective view of the adapter according to the invention, Fig. 2a / 2b each in a top view the foot part and the head part of the adapter, Fig. 3 in a side view the adapter, Fig. 4 in a cutaway (AA) side view of the adapters, Fig. 5 in a second side view the adapter, and Fig. 6 in a cutaway (AA) side view of the adapter arranged in a roll of foil.

[0055] The one in the Fig. The adapter 100 shown in Figures 1-6 according to the invention has an adapter element 10 which passes through an opening 210 of a coreless film roll 200 ( Fig. 6) is inserted from the outside into the film roll 200 and enables the machine unwinding of the film roll 200.

[0056] The adapter element 10 has a substantially cylindrical shape with a central through-opening 23a. The adapter element 10 has a lateral surface 12 that extends between an adapter ring 11 of a head section 13 and the outer edge of a foot section 14 of the adapter element 10. The lateral surface 12 comprises only the laterally visible parts of the adapter element 10. The head section 13 serves as a stop when inserting the adapter element 10 into the film roll 200. On the lateral surface 12 of the adapter element 10 are four first longitudinally extended clamping elements 15 and four second longitudinally extended clamping elements 16, which are arranged along the longitudinal axis of the adapter element 10 and protrude from the lateral surface 12.

[0057] In contrast to the cylindrical shape of the outer surface, a conical section 25 is provided adjacent to the head 13, onto which the film roll 200 is slid for fixation. The foot 14 can also have a conical shape, which is not shown here, and which is intended to facilitate the insertion of the adapter 100 into the opening 210 of the film roll 200. The outer diameter of the adapter element 10 would be slightly smaller than the inner diameter of the film roll 200, so that the adapter element 10 can be inserted into the roll 200 without damaging the inner layers of the film.

[0058] The first longitudinally extended clamping elements 15 are located in a first area 17 of the surface 12 adjacent to the head section 13, and the second longitudinally extended clamping elements 16 are located in a second area 18 adjacent to the foot section 14 of the surface 12. All first longitudinally extended clamping elements 15 are positioned in the same way relative to each other, as are the second longitudinally extended clamping elements 16.

[0059] Otherwise, the first longitudinally extended clamping elements 15 and the second longitudinally extended clamping elements 16 are each maximally spaced apart from each other and arranged parallel to each other and to the main axis of the adapter element 10.

[0060] The first and second clamping elements 15, 16 preferably consist of a spring-elastic material, preferably in the form of a wire, which can be reversibly deformed by external pressure. This pressure is applied inside the film roll 200 by inserting the adapter into the opening 210 of the film roll 200, and by making contact between the apex points of the first clamping elements 15 and the second clamping elements 16 on the outer surface 12 of the film roll 200. Preferably, the first and second clamping elements 15, 16 are dimensioned such that the distance between the apex points of two opposing clamping elements 15, 16 is greater than the inner diameter of the opening 210 of the film roll 200. The contact pressure generated by the clamping elements 15, 16 can thus be varied by the aforementioned distance between the two apex points and the spring force of the clamping elements 15, 16.

[0061] As already explained, according to the invention, slippage of the adapter element 10 in the film roll 200 is avoided and the film roll 200 is held under tension from the inside in such a way that it is stabilized when unwinding, when it has already been largely unwound.

[0062] Furthermore, four grooves 19 are provided on the cylindrical surface 12, arranged along the longitudinal axis and thus parallel to the longitudinally extended first and second clamping elements 15, 16, with the grooves 19 positioned centrally between the first and second clamping elements 15, 16. The grooves 19 also extend completely over the adapter element 10, i.e., including the head section 13 and the foot section 14. As a result, groove holes 20 are found at the end of the grooves 19 in the head section 13. Fig. 2b), which enables easy removal of the adapter element 10 from the film roll 200.

[0063] The grooves 19 are designed to accommodate coreless film rolls 200 mm with a non-perfectly round inner diameter. Various winding shafts are available on the market for manufacturing coreless film rolls 200 mm. Some of these winding shafts feature an internal roll geometry with indentations and raised sections due to hydraulic clamping segments. To accommodate these raised sections and ensure a precise fit of the adapter 100 within the roll 200 mm, the adapter 100 is additionally equipped with grooves 19 to accommodate these raised sections. This provides additional fixation for the corresponding film rolls 200 mm.

[0064] In the area of ​​the clamping elements 15, 16, there is a flattened surface below them, which is referred to as the clamping element receiving area 21. This area 21 serves to provide space for the film in the case of a non-circular roll geometry as described above. It is advantageous if the end of the clamping element receiving area 21 extends into the head section 13 or the foot section 14 to ensure a more even pressure distribution. At the two outer ends of this clamping element receiving area 21, there are openings / through-holes 22 in the adapter 100, which run along the longitudinal axis of the adapter element 10. The clamping element 15, 16 is fixed in these openings / through-holes 22.

[0065] Inside the head section 13 and the foot section 14 of the adapter 100, there is a conical receptacle 23 in each case. This is the area in which a cone of the device for unwinding the film roll 200 is fixed to the adapter 100. Since various devices have technical features, e.g., in the form of screw heads, in the conical area, fixing holes 24 are provided for this purpose (only in Fig. 2b), which accommodate these elements. This also provides further fixation between adapter 100 and the device.

[0066] Openings 28 of the through-holes 22 are provided on the end face 26 of the head section 13 and on the end face 27 of the foot section. These through-holes contain screws (not shown) by means of which the ends of the clamping elements 15, 16 located in the through-holes 22 can be actuated. The clamping element 15, 16 can be brought to the desired tension by means of the screws. Reference symbol list 100 adapters 200 rolls of foil 210 Opening 10 adapter elements 11 Adapter ring 12 Surface area 13 Headboard 14 Foot section 15 first longitudinally extended clamping element 16 second longitudinally extended clamping element 17 first area 18 second area 19 Nut 20 groove holes 21 Clamping element mounting area 22 openings / passage openings 23 Cone mount 24 fixing holes 25 Conical section 26 Front surface 27 Front surface 28 openings QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 2011 / 0041458 A1

[0011] US 10 308 474 B2

[0012] DE 20 2023 106 929 U1

[0013]

Claims

[1] Adapter (100) for use in unwinding film from coreless film rolls (200) having a roll passage with a first and a second opening (210) at opposite ends of the coreless film roll (200), wherein the adapter (100) comprises: a longitudinally extended adapter element (10), wherein the adapter element (10) has at a first free end a projecting head section (13) with an adapter ring (11) as a stop for the film roll (200), and wherein the adapter element (10) has on the lateral surface (12), which extends between the adapter ring (11) and a second free end, at least two first longitudinally extended clamping elements (15) and at least two second longitudinally extended clamping elements (16) for clamping the adapter element (10) in the roll passage, which are fixed on the lateral surface (12) and protrude from the lateral surface (12), wherein the at least two first longitudinally extended clamping elements (15) are arranged in a first region (17) of the lateral surface (12) and the at least two second longitudinally extended clamping elements (16) are arranged in a second region (18) of the lateral surface (12), wherein the first region (17) and the second region (18) of the lateral surface (12) one after the other,are arranged with respect to the main axis of the adapter element (10), wherein the at least two first longitudinally extended clamping elements (15) and the at least two second longitudinally extended clamping elements (16) are each maximally spaced apart from each other and are arranged parallel to each other and to the main axis of the adapter element (10). [2] Adapter (100) according to claim 1, wherein the adapter (100) further comprises: at least two first longitudinally extended grooves (19) arranged on the lateral surface (12), which are maximally spaced apart from each other and are arranged parallel to each other and to the main axis of the adapter element (10). [3] Adapter (100) according to claim 2, wherein the at least two first longitudinally extended clamping elements (15) are arranged between the at least two first longitudinally extended grooves (19). [4] Adapter (100) according to claim 2 or 3, wherein each of the at least two first longitudinally extended grooves (19) is followed by a second longitudinally extended groove (19) in the same orientation. [5] Adapter (100) according to one of the preceding claims, wherein a second longitudinally extended clamping element (16) in the same orientation as the first longitudinally extended clamping elements (15) is arranged downstream of each of the at least two first longitudinally extended clamping elements (15). [6] Adapter (100) according to one of the preceding claims, wherein the downstream second longitudinally extended clamping elements (16) and / or the downstream second longitudinally extended grooves (19) each run on the same axis as the respective first longitudinally extended clamping element (15) and / or the respective first longitudinally extended groove (19). [7] Adapter (100) according to one of the preceding claims, wherein 4 or 6, preferably 4 first and 4 second longitudinally extended clamping elements (15, 16) are provided. [8] Adapter (100) according to any one of the preceding claims 2 to 7, wherein 4 or 6, preferably 4 first longitudinally extending grooves (19) are provided. [9] Adapter (100) according to any one of the preceding claims, characterized by , that the at least two first and second longitudinally extended clamping elements (15, 16) each have a length of 1 / 10 to 2 / 5, preferably 1 / 4 of the length of the lateral surface (12) of the adapter element (10). [10] Adapter (100) according to any one of the preceding claims 2 to 9, wherein the at least two first grooves (19) extend over the entire length of the lateral surface (12) of the adapter element (10) or wherein the at least two first grooves (19) and second grooves (19) extend overlapping over the entire length of the lateral surface (12) of the adapter element (10). [11] Adapter (100) according to any one of the preceding claims, characterized by that the grooves (19) are arranged centrally between the first and second longitudinally extended clamping elements (15, 16). [12] Adapter (100) according to any one of the preceding claims, characterized by , that the lateral surface (12) has a cylindrical basic shape. [13] Adapter (100) according to any one of the preceding claims, characterized bythat the adapter element (10) is at least partially conical, preferably adjacent to the head part (13), and that the conically formed area(s) taper from the head part (13) towards the foot part (14). [14] Adapter (100) according to any one of the preceding claims, characterized by , that the adapter element (10) is flattened in the area of ​​the first and second longitudinally extended clamping elements (15, 16), wherein preferably the first and second grooves (19) run between the flattened areas. [15] Adapter (100) according to any one of the preceding claims, characterized by , that the at least two first and second clamping elements (15, 16) consist of a wire made of metal or polymer, preferably of metal, particularly preferably of spring steel. [16] Adapter (100) according to claim 15, characterized by that the wire is a round wire, a flat wire, or a profile wire [17] Adapter (100) according to any one of the preceding claims, characterized by , that the at least two first and second clamping elements (15, 16) are each inserted with their free ends into openings or through-openings (22) in the lateral surface (12). [18] Adapter (100) according to claim 17, characterized by , that the free ends of the at least two first and second clamping elements (15, 16) are flattened in the direction of the openings (22) and are located in this state in the openings or through openings (22). [19] Adapter (100) according to claim 17 or 18, characterized by, that at least in one of the two through-openings (22), in which a free end of a first or second longitudinally extended clamping element (15, 16) is arranged, a screw for clamping or fixing the first or second longitudinally extended clamping element (15, 16) is arranged such that the head of the screw can be actuated from one side of the through-opening (22), while the other end of the screw acts on the end of the respective clamping element (15, 16) located in the through-opening (22). [20] Adapter (100) according to any one of the preceding claims, characterized by , that the adapter element (10) has a cone receptacle (23) on the head part (13), designed to precisely accommodate a cone of a stretch wrapping machine. [21] Adapter (100) according to any one of the preceding claims 2 to 20, characterized by , that at the end of the respective groove (19) in the head part (13) of the adapter element (10) there is a groove hole (20). [22] Adapter (100) according to any one of the preceding claims 1 to 21, characterized by , that the at least two first longitudinally extended clamping elements (15) and the at least two second longitudinally extended clamping elements (16) together form at least two third longitudinally extended clamping elements in one piece.

Images