Footwear last for manufacturing a footwear part, manufacturing system, and method for manufacturing a footwear part

Abstract

The invention pertains to a footwear last (10a-e) for manufacturing a footwear part, comprising a mid- and forefoot section (12a-e) and a hindfoot section (14a-e) having an interface (16a-e) for connecting to a handling unit (18a). In a first aspect of the invention, the mid- and forefoot section (14a-d) comprises at least one cavity (20a-c). In a second aspect of the invention, the hindfoot section (14c; 14e) has a higher density than the mid- and forefoot section (12c; 12e). The invention further pertains to a manufacturing system (32a) for manufacturing a footwear part, and to a method for manufacturing a footwear part using a footwear last (10a-e) in a manufacturing system (32a).

Description

[0001] On Clouds GmbH 1 / 22

[0002] Footwear last for manufacturing a footwear part, manufacturing system, and method for manufacturing a footwear part

[0003] Technical Field

[0004] The present invention relates to a footwear last for manufacturing a footwear part, a manufacturing system for manufacturing a footwear part, and a method for manufacturing a footwear part by using such a footwear last in such a manufacturing system.

[0005] Background

[0006] In the footwear industry, shoe soles are frequently manufactured using footwear lasts. The previously known footwear lasts are made entirely from solid homogeneous material. For example, known footwear lasts are made from high-density polyethylene and therefore have a high weight.

[0007] In recent years, the automation of manufacturing processes has gained increasing importance, including in footwear manufacturing. Robots and automated handling systems are increasingly employed to improve efficiency, consistency, and productivity.

[0008] For example, WO 2022 / 069583 A1 discloses a method for producing a textile material, in particular a shoe upper, by applying a molten thermoplastic filament onto a footwear last to form the textile material with a plurality of superimposed loops. Herein, the thermoplastic filament is ejected from a spray head in a molten state as a helical strand and applied to the shoe footwear last, wherein the footwear last is moved robotically relative to the spray head, and this movement can be very fast.

[0009] The conventional footwear lasts used in footwear production, for example in the method disclosed in WO 2022 / 069583 A1 as mentioned above, present challenges in the context of automating footwear production as their high weight complicates automated handling. In particular, a heavy footwear last requires a correspondingly powerful drive, acceleration and decelerating are more difficult and robot joints are subject to particularly high stresses. Consequently, there is a need for improved footwear last design that better support automated manufacturing processes, in particular with regard to robotic handling.

[0010] Summary

[0011] The invention concerns a footwear last for manufacturing a footwear part, comprising a mid- and forefoot section and a hindfoot section having an interface for connecting to a handling unit.

[0012] According to a first aspect of the invention, which may be envisioned on its own or in combination with other aspects disclosed herein, the mid- and forefoot section may comprise at least one cavity.

[0013] ONA-21576-P-WOOn Clouds GmbH 2 / 22

[0014] According to a second aspect of the invention, which may be envisioned on its own or in combination with other aspects disclosed herein, the hindfoot section may have a higher density than the mid- and forefoot section.

[0015] The invention further pertains to a manufacturing system for manufacturing a, in particular the aforementioned, footwear part, comprising a footwear last as described herein and a, in particular the aforementioned, handling unit attached to the interface.

[0016] In addition, the invention pertains to a method for manufacturing a, in particular the aforementioned, footwear part by using a footwear last as described herein in a manufacturing system as described herein.

[0017] The solutions according to the invention enable an improvement in the production of footwear parts, in particular with regard to the automation of manufacturing of footwear parts. A reduction in the weight of the footwear lasts can be achieved. This can reduce the weight-related requirements for movement and transport of the footwear last during manufacturing. Advantageously, inertia can be reduced and, as a result, the movement and transport properties, for example with respect to the acceleration, deceleration and rotation of the footwear last, can be improved. As the hindfoot section has a higher density than the mid- and forefoot section, a center of mass of the footwear last can be shifted towards the interface, thereby improving the movement properties with regard to the rotation of the footwear last in particular. This can be achieved by having the at least one cavity in the mid-and forefoot section, and / or by other means, for example by using different materials for the mid- and forefoot section and the hindfoot section. The reduced weight can also reduce vibrations during the manufacturing process allowing for increased precision during manufacturing and thus improve the quality of the footwear parts to be produced.

[0018] The footwear part may be part of an article of footwear or may constitute the entire article of footwear. Furthermore, the footwear part may be a precursor part from which the final article of footwear may be obtained, in particular by at least one manufacturing step. The article of footwear may be a sports shoe, in particular a running shoe, a tennis shoe, or the like, a sneaker, a hiking shoe, or the like. The article of footwear, in particular the footwear part, may comprise at least an upper, a sole unit connected to the upper, and possibly a fastening unit for fastening the article of footwear to a wearer’s foot. The sole unit preferably comprises an outsole and a midsole and may additionally comprise an insole. The fastening unit may comprise a lacing system, a hook and loop fastener, a zipper, a buckle system, a button closure system, a combination thereof, or the like.

[0019] The footwear part may comprise at least one footwear element. The at least one footwear element may be part of, constitute, or be a precursor of the sole unit, in particular the midsole, the insole and / or the outsole, the upper, and / or the fastening unit. The at least one footwear element may for example be an upper element, a midsole element, or the like. ONA-21576-P-WOOn Clouds GmbH 3 / 22

[0020] The upper element may be part of the upper, form the entire upper, or be a precursor of the upper. Likewise, the midsole element may be part of the midsole, form the entire midsole, or be a precursor of the midsole.

[0021] The footwear part, in particular the at least one footwear element, may partially or entirely be a textile, a foam element, a rubber element, or the like. The footwear part, in particular the at least one footwear element, may be formed partially or entirely from a thermoplastic filament.

[0022] The thermoplastic filament may be a polymer composition. The polymer composition may comprise, for example, polyester, polyamide, polyether block amide (PEBA), for example PEBAX® (Arkema), thermoplastic polyurethane (TPU), such as Desmopan®2790A or Desmopan® 9392A (Covestro), ethylene vinyl acetate (EVA), polyolefin, such as polyethylene or polypropylene, or mixtures thereof. The thermoplastic filament may contain one or more additives, like pigments, foaming agents, cross-linking agents, etc.

[0023] The thermoplastic filament may be provided by the manufacturing system, in particular a filament output unit of the manufacturing system. The filament output unit may be configured to spray the thermoplastic filament. The term “spraying” in this context means that the thermoplastic filament travels through air, for example over a distance of at least 2 cm, at least 5 cm, or at least 10 cm, before being deposited and forming the at least one footwear element. Spraying the thermoplastic filament as disclosed herein is not to be confused with 3D printing, which is a completely different process. The at least one footwear element made from the sprayed thermoplastic filament may have a porous, yet non-foamy, and / or fibrous structure, in particular contrary, for example, to a footwear element manufactured by 3D printing and / or by molding and possibly by subsequent foaming.

[0024] The filament output unit may comprise a dosing unit, a melting unit, and / or a nozzle unit. An example of such a filament output unit is disclosed in WO 2022 / 069583 A1.

[0025] The filament output unit may be configured to process a filament raw material, e.g. a polymeric material or the like, in order to provide the thermoplastic filament. The melting unit may be configured to melt the filament raw material, which may then be used to manufacture the at least one footwear element. The melting unit may include an extruder, with the extruder possibly having a barrel and a screw. The screw may be arranged inside the barrel. The melting device may also include an output material heating unit. The filament raw material may be melted by the output material heating unit. By means of the nozzle unit the molten filament raw material may be dispensed as the thermoplastic filament.

[0026] The filament raw material may comprise a polymer composition, that may comprise, for example, polyester, polyamide, polyether block amide (PEBA), for example PEBAX® (Arkema), thermoplastic polyurethane (TPU), such as Desmopan® 2790A or Desmopan® 9392A (Covestro), ethylene vinyl acetate (EVA), polyolefin, such as polyethylene or ONA-21576-P-WOOn Clouds GmbH 4 / 22

[0027] polypropylene, or mixtures thereof. The filament raw material may contain one or more additives, like pigments, foaming agents, cross-linking agents, etc.

[0028] The dosing unit may comprise a pump, a pump drive and a dosing head. The pump may be configured to generate pressure for dispensing the molten filament raw material as the thermoplastic filament, in particular through the nozzle unit. The pump may be configured to control, in particular fine tune, the output pressure of the molten filament raw material through the nozzle unit. Alternatively, the filament output unit may be implemented without a pump to generate pressure for dispensing the thermoplastic filament, wherein the thermoplastic filament may be dispensed by means of the extruder and preferably sprayed as the thermoplastic filament.

[0029] The nozzle unit may comprise at least one gas outlet opening, through which a flow of gas, in particular compressed air, may be output. The flow of gas may be provided to influence the filament emerging from the nozzle unit. Preferably, the nozzle unit is designed in such a way that a helical filament is produced. This helical shape of the filament may be generated by a corresponding application of gas flow from several gas outlet openings. The gas outlet openings may be arranged around a filament outlet of the nozzle unit, in particular at a uniform distance and preferably in a circular arrangement. Preferably, a gas outlet direction of the at least one gas outlet opening extends at an angle to a filament dispense direction of the nozzle unit. Alternatively, the nozzle unit may also be rotated to create the helical shape of the filament.

[0030] The thermoplastic filament may be applied, in particular sprayed, onto the footwear last for manufacturing, and preferably shaping, the at least one footwear element.

[0031] The handling unit may be configured to control an application path for applying the thermoplastic filament onto the footwear last. The application path preferably refers to a relative movement path of the nozzle unit with regard to the footwear last. The handling unit may be configured to generate a relative movement of the footwear last with respect to the filament output unit, in particular the nozzle unit. For example, the handling unit may be, preferably detachably, connected to the footwear last to move it. The handling unit may be implemented as or may comprise a robotic handler or the like.

[0032] The thermoplastic filament may be formed as a plurality of path segments, preferably in the form of loops, to produce the at least one footwear element. In other words, the filament forming the at least one footwear element may be arranged in a looped manner having several intersecting turns and forming several layers one on top of the other. Such structure is, for example, disclosed in WO 2022 / 069583 A1.

[0033] Alternatively, the thermoplastic filament may at least partially or entirely be formed as a wadding. Herein, a “wadding” may be understood as a structure in which the thermoplastic filament is in a disordered state and may take up a higher volume compared ONA-21576-P-WOOn Clouds GmbH 5 / 22

[0034] to an ordered state of the thermoplastic filament, where the thermoplastic filament may be present as a plurality of path segments, preferably in the form of loops. Such wadding may be obtained by an increased distance between the nozzle unit and the footwear last during application of the thermoplastic filament compared to a distance between the nozzle unit and the footwear last while applying the thermoplastic filament in the form of the plurality of path segments, in particular loops.

[0035] The footwear last may be set up to shape the at least one footwear element. For example, the footwear last may have a surface, in particular a footwear element contact surface, that may be configured to define the shape of the at least one footwear element. For example, the at least one footwear element may be shaped by applying it to the surface, in particular the footwear element contact surface, of the footwear last. The footwear element contact surface may particularly refer to a surface of the footwear last on which the at least one footwear element rests after being applied to the footwear last.

[0036] The footwear last may comprise a footwear part contact surface. The footwear element contact surface may be part of or constitute the entire footwear part contact surface. The footwear part contact surface may particularly refer to a surface of the footwear last on which the footwear part rests after being manufactured and before being separated from the footwear last, for example by means of the handling unit and / or manually.

[0037] In a preferred embodiment, the at least one footwear element is an, in particular the aforementioned, upper element manufactured by applying the thermoplastic filament onto the footwear last. For example, the footwear part may comprise a midsole and the upper element. The midsole may be arranged on the footwear part contact surface, in particular a midsole contact surface of the footwear last, during manufacturing the footwear part, in particular prior to applying the thermoplastic filament onto the footwear last, preferably onto the footwear element contact surface, to form the upper element. The midsole contact surface may be part of the footwear part contact surface and may refer to a surface of the footwear last on which the midsole rests when attached to the footwear last at least during manufacturing.

[0038] In a preferred embodiment, the footwear last consists of the mid- and forefoot section and the hindfoot section. The mid- and forefoot section may comprise a midfoot section that represents a midfoot of a foot and a forefoot section that represents a forefoot of a foot. The hindfoot section may represent a hindfoot of a foot.

[0039] The at least one cavity of the mid- and forefoot section may be a void and / or a free, unfilled space. The at least one cavity of the mid- and forefoot section may be an internal cavity or a recess. The recess may be understood as a kind of open cavity, i.e. a cavity that is open on at least one side and / or not fully enclosed. The recess may be in particular different from a slit, a channel, a grooved profile, and / or any other surface structure. It may ONA-21576-P-WOOn Clouds GmbH 6 / 22

[0040] be envisaged that the at least one cavity of the mid- and forefoot section may be provided by an intrinsic material property of a material, in particular a foam or the like, from which the mid- and forefoot section is partially or entirely formed. Alternatively, the at least one cavity of the mid- and forefoot section may also be formed by a shaping of the mid- and forefoot section. Channels for guiding materials for manufacturing the footwear part, cooling channels for transporting a cooling fluid, heating channels, or the like may not be understood as such a “cavity”. In other words, the at least one cavity of the mid- and forefoot section may be different from a material guiding channel, a heating channel, a cooling channel, or the like. The at least one cavity of the mid- and forefoot section may be primarily or solely present for weight reduction. The mid- and forefoot section may comprise only one cavity, or a multitude of cavities. For example, also hundreds, or thousands of cavities may be envisaged to be present in the mid- and forefoot section. The at least one cavity of the mid- and forefoot section may be arranged in the midfoot section and / or in the forefoot section. It may also be envisaged that the midfoot section comprises the at least one cavity and the forefoot section comprises at least one further cavity.

[0041] In a preferred embodiment, the mid- and forefoot section may be essentially hollow. This means that a particularly lightweight footwear last can be provided. It is possible to shift the center of mass of the footwear last in the direction of a handling axis of the footwear last, which can, for example, improve the movement properties of the footwear last with regard to rotations around the handling axis.

[0042] A body that is “essentially hollow” may have at least 50 %, or at least 75 %, or at least 90 %, free, unfilled space in relation to a total volume of the body. In the context of the present description, the total volume of a body may denote its material volume and its enclosed volume. In other words, the total volume of a body may correspond to its outer envelope.

[0043] The hindfoot section may comprise at least one cavity. This enables a particularly light footwear last and thus improves its transportation properties.

[0044] The description with regard to the at least one cavity of the mid- and forefoot section may be applied analogously to the at least one cavity of the hindfoot section. It may be envisaged that the at least one cavity of the mid- and forefoot section and the at least one cavity of the hindfoot section may form a continuous cavity. Alternatively, the at least one cavity of the mid- and forefoot section and the at least one cavity of the hindfoot section may be formed separately from each other.

[0045] In a preferred embodiment, the hindfoot section may be essentially hollow. This means that a particularly lightweight footwear last can be provided.

[0046] ONA-21576-P-WOOn Clouds GmbH 7 / 22

[0047] It may be envisaged that the mid- and forefoot section and / or the hindfoot section may at least partially be open at a bottom side of the footwear last. This saves material and therefore weight, and a particularly light footwear load can be made available.

[0048] The mid- and forefoot section and / or the hindfoot section may be open to at least 25 %, or to at least 50 %, or to at least 75 %, or to at least 90 % at the bottom side of the footwear last. The bottom side may correspond to a sole section of the footwear last. It may be envisaged that a sole section of the mid- and forefoot section and / or the hindfoot section may be partially open, for example to at least 25 %, or to at least 50 %, or to at least 75 %, or to at least 90 %, or entirely open. For example, the at least partially open bottom side may be closed by the midsole element or the midsole during manufacturing, preferably also closing the at least one cavity.

[0049] The mid- and forefoot section and / or the hindfoot section may be rigid. This ensures high accuracy and repeatability for manufacturing.

[0050] “Rigid” in this context may mean that the mid- and forefoot section and / or the hindfoot section are formed such that they do not deform, at least during the manufacture of the footwear part. In the context of a body, the term “not deform” shall be understood to mean that the body substantially may retain its intended shape and dimensions under normal use conditions. Insignificant or unavoidable elastic deflections, dimensional tolerances, or minimal deformations occurring during handling, movement, or operation may not be regarded as deformation in the sense of this definition. In a preferred embodiment, the mid- and forefoot section and / or the hindfoot section are not inflatable or deflatable. It may also be envisaged for the entire footwear last to be rigid. At least the part of the footwear last that forms the footwear part contact surface may be rigid.

[0051] In a preferred embodiment, the mid- and forefoot section and the hindfoot section may be formed in one piece. Alternatively, the mid- and forefoot section and the hindfoot section may be implemented as separate parts that may be detachably fixed to each other, for example via a clamp connection, a screw connection, a latching connection, or the like. It may be envisaged that the mid- and forefoot section and / or the hindfoot section may be exchangeable with various other mid- and forefoot sections and / or hindfoot sections respectively, preferably having different material compositions, densities, weights, sizes, or the like. Thus, the footwear last can be easily adapted to different manufacturing requirements or a mid- and forefoot section and / or a hindfoot section that may be damaged, dirty, or the like can easily be maintained and / or replaced. It may also be envisaged that the mid- and forefoot section and the hindfoot section may be movable relative to each other to adjust the size of the footwear last, in particular of the footwear part contact surface, preferably to manufacture footwear parts of different sizes.

[0052] ONA-21576-P-WOOn Clouds GmbH 8 / 22

[0053] Moreover, it may also be envisaged that the mid- and forefoot section and / or hindfoot section consist / consists of multiple parts, that may be exchangeable and / or movable relative to each other. The footwear last may also be separable in a horizontal plane, i.e. in a longitudinal plane of the footwear last.

[0054] The footwear last may comprise at least one reinforcement element arranged in the at least one cavity. This ensures the required stability of the footwear last, in particular the at least one cavity, while at the same time reducing the weight of the footwear last by means of the at least one cavity.

[0055] The at least one reinforcement element may be constituted by a reinforcement rib, an increased material thickness, a reinforcement plate, a reinforcement strut, or the like. The at least one reinforcement element may be formed in one piece with a part of the footwear last defining the at least one cavity, in particular with the mid- and forefoot section and / or the hindfoot section, for example by a glued connection, by being manufactured in one piece, by a welded connection, or the like. Alternatively, the at least one reinforcement element may be formed separately to the part of the footwear last defining the at least one cavity, wherein the at least one reinforcement element may be, in particular detachably, fixed to the part defining the at least one cavity, for example via a screw connection, a clamping connection, a latching connection, or the like. The at least one reinforcement element may be arranged in the at least one cavity of the mid- and forefoot section and / or the hindfoot section. The footwear last may comprise one or multiple reinforcement elements that may be arranged in the at least one cavity of the mid- and forefoot section and / or the hindfoot section.

[0056] The at least one reinforcement element may provide at least one additional functionality apart from reinforcement. In particular, the at least one reinforcement element may allow attachment of a holding element, preferably a magnetic element, for example a permanent magnet, of the footwear last. For example, the at least one reinforcement element may have a receptacle for receiving the holding element, in particular the magnetic element. The holding element, in particular the magnetic element, may be configured for attachment of an at least partially magnetic sole unit and / or an at least partially magnetic shaping element of the footwear last for changing and / or adapting an outer shape of the footwear last, in particular during application of the thermoplastic filament onto the footwear last for forming the upper element.

[0057] In one embodiment the footwear last may comprise at least two footwear last components that may be attached or attachable to each other. In this case the at least one reinforcement element arranged at one of the footwear last components may comprise an attachment element for attaching the at least one other footwear last component.

[0058] ONA-21576-P-WOOn Clouds GmbH 9 / 22

[0059] Further still, the at least one reinforcement element may constitute at least a part of the interface for connecting the handling unit.

[0060] The footwear last, in particular the mid- and forefoot section and / or the hindfoot section, may partially, preferably to at least 10 %, or at least 50 %, or at least 75 %, or at least 90 % in relation to a total weight of the footwear last or in particular the mid- and forefoot section and / or the hindfoot section respectively, be made from a non-porous material, preferably from a plastic, for example from high-density polyethylene.

[0061] In one embodiment, the mid- and forefoot section and / or the hindfoot section may at least partially be made from a metal. This makes it possible to provide a footwear last in which the at least one cavity can be particularly large and which still has a high mechanical and thermal stability.

[0062] A body that is “at least partially made from a metal” may be made of at least 10 %, or at least 50 %, or at least 75 %, or at least 90 %, or completely of a metal or a metal alloy in relation to its total weight. It may also be envisaged that the footwear last may at least partially be made from a metal. The mid- and forefoot section and / or the hindfoot section may at least partially be made from aluminum, titanium, or the like.

[0063] Alternatively or additionally, the mid- and forefoot section and / or the hindfoot section may at least partially be made from a porous material. This makes it particularly easy to produce a footwear last with a particularly low weight.

[0064] The porous material may be a metal foam, for example an aluminum foam, a plastic foam, in particular a rigid foam, for example expanded polystyrene, or the like. A body that is “at least partially made from a porous material” may be made of at least 10 %, or at least 50 %, or at least 75 %, or at least 90 %, or completely of a porous material in relation to its total weight. It may also be envisaged that the footwear last may be entirely made from a porous material. The at least one cavity may be provided by manufacturing the mid- and forefoot section and / or the hindfoot section at least partially from a porous material.

[0065] The mid- and forefoot section and the hindfoot section may at least partially be made from different materials. This allows for adjusting the position of the center of mass of the footwear last and a particularly advantageous positioning of the center of mass of the footwear last, for example with regard to its transport properties, can be achieved.

[0066] Preferably, the mid- and forefoot section may be made from a material or a material combination that is lighter than a material or material combination from which the hindfoot section is made.

[0067] The center of mass of the footwear last may be closer to a, in particular the aforementioned, handling axis defined by the interface compared to a comparative footwear last made from a solid homogeneous material. In this way, improved movement properties can be achieved with regard to the footwear last, in particular with regard to rotations of the ONA-21576-P-WOOn Clouds GmbH 10 / 22

[0068] footwear last around the handling axis. The handling axis may correspond to a movement axis of the handling unit, around which the footwear last may be rotated by the handling unit.

[0069] The method for manufacturing the footwear part using the footwear last in the manufacturing system may comprise: a transport step of moving the footwear last relative to a filament output unit using the handling unit and an application step of applying at least one, in particular the aforementioned, thermoplastic filament onto the footwear last to form a plurality of path segments, in particular loops, on the footwear last along an, in particular the aforementioned, application path for forming at least one, in particular the aforementioned, footwear element of the footwear part. By using the footwear last as described herein, improved transport properties can be achieved during the manufacturing method. In particular, the footwear last can be accelerated and decelerated faster, so that shorter cycle times are possible. In addition, less energy is required for transportation, so that motors and drives for moving the footwear last have to apply less power. This also allows a manufacturing method to be realized in which particularly little wear occurs on the manufacturing system, for example on the joints of the handling unit. The low weight also means that vibrations and tracking movements can be reduced, resulting in a particularly high positioning accuracy of the footwear last.

[0070] The transport step may be performed prior, during, and after the application step. The footwear last may be moved translatory and / or rotationally, preferably around the handling axis, during the transport step.

[0071] The methods, elements and articles disclosed herein are not intended to be limited to the application and embodiment described above. In particular, they may have a number of individual elements, components and units as well as process steps deviating from a number specified herein in order to fulfill a mode of operation described herein. In addition, in the case of value ranges specified in this disclosure, values lying within the specified limits are also to be regarded as disclosed.

[0072] In particular, it is pointed out that all features, properties and methods described in relation to an element, or an article are transferable mutatis mutandis to methods and can be used in the sense of the invention and are deemed to be co-disclosed. The same applies in the opposite direction. This means that structural features mentioned in relation to methods can also be taken into account and claimed within the scope of device claims and can also be counted as part of the disclosure.

[0073] In the following, the present invention is described by way of example with reference to the accompanying figures. The drawing, the description and the claims contain numerous features in combination. The skilled person will also usefully consider the features individually and use them sensibly in combination in the context of the claims.

[0074] ONA-21576-P-WOOn Clouds GmbH 11 / 22

[0075] If there is more than one example of a particular object, only one of them may be provided with a reference sign in the figures and in the description. The description of this specimen can be transferred accordingly to the other specimens of the object. If objects are named in particular by means of numerical words, such as first, second, third object, etc., these are used to name and / or assign objects. Accordingly, for example, a first object and a third object, but no second object, can be included. However, a number and / or sequence of objects could also be derived from numerical words.

[0076] Brief description of the drawings

[0077] Embodiments of the present disclosure will now be described by way of example only and with reference to the following accompanying drawings.

[0078] Figure 1 contains a schematic representation of a manufacturing system for manufacturing a footwear part.

[0079] Figure 2 shows a footwear last of the manufacturing system in a lateral crosssection.

[0080] Figure 3 shows a schematic sequence of a method for manufacturing the footwear part.

[0081] Figure 4 shows a footwear last of a first alternative embodiment in a lateral crosssection.

[0082] Figure 5 shows the footwear last of Figure 4 in a bottom view.

[0083] Figure 6 shows a footwear last of a second alternative embodiment in a lateral crosssection.

[0084] Figure 7 shows a footwear last of a third alternative embodiment in a lateral crosssection.

[0085] Figure 8 shows footwear last of a fourth alternative embodiment in a side view.

[0086] Detailed Description

[0087] Figure 1 shows a schematic overview of a manufacturing system 32a for manufacturing a footwear part. The manufacturing system 32a comprises a footwear last 10a and a handling unit 18a.

[0088] The footwear part is part of an article of footwear, in particular a running shoe. The footwear part comprises an upper element and a midsole element 40a. The midsole element 40a constitutes a midsole of a sole unit of the article of footwear. The sole unit comprises an outsole that is attached to the midsole element 40a. The upper element forms an upper of the article of footwear.

[0089] The upper element is made from a sprayed thermoplastic filament F. The thermoplastic filament F is a polymer composition. The polymer composition is a ONA-21576-P-WOOn Clouds GmbH 12 / 22

[0090] thermoplastic polyurethane, such as Desmopan® 2790A or Desmopan® 9392A (Covestro). The thermoplastic filament F of the upper element comprises a plurality of path segments in the form of intersecting loops (not shown here).

[0091] The thermoplastic filament F is provided by a filament output unit 38a of the manufacturing system 32a. The filament output unit 32a is configured to apply, in particular spray, the thermoplastic filament F onto the footwear last 10a for shaping the upper element thereon. The filament output unit 32a comprises a dosing unit 42a, a melting unit 44a and a nozzle unit 46a.

[0092] The melting unit 44a is configured to melt a filament raw material that is a polymer composition, e.g. a thermoplastic polyurethane, which is then used to manufacture the upper element. The melting unit 44a comprises an extruder having a barrel 48a and a screw 50a. The screw 50a is arranged in the barrel 48a. For melting the filament raw material, the melting unit 44 comprises an output material heating unit (not shown).

[0093] The nozzle unit 46a is configured to dispense the molten filament raw material. The dosing unit 42a comprises a pump 52a, a pump drive 54a to drive the pump 52a and a dosing head 56a. The pump 52a generates pressure for dispensing the molten filament raw material as the thermoplastic filament F through the nozzle unit 46a. The pump 52a is configured to control, in particular fine tune, the output pressure of the molten filament raw material through the nozzle unit 46a. The nozzle unit 46a comprises a plurality of gas outlet openings (not shown here), through which a flow of gas, in particular compressed air, is output. The flow of gas output by the gas outlet openings is used to influence the filament F emerging from the nozzle unit 46a to form a helical shaped filament F.

[0094] The filament output unit 38a and the method of forming the helical shaped filament F is disclosed in more detail in WO 2022 / 069583 A1.

[0095] The handling unit 18a is detachably attached to the footwear last 10a. The handling unit 18a is configured to move the footwear last 10a. The handling unit 18a is configured to control an application path P for applying, in particular spraying, the thermoplastic filament F onto the footwear last 10a to form the upper element. The handling unit 18a is configured to generate a relative movement of the footwear last 10a and the filament output unit 38a, in particular the nozzle unit 46a, by moving the footwear last 10a. The handling unit 18a is detachably connected to the footwear last 10a to create the relative movement during application of the thermoplastic filament F onto the footwear last 10a for forming the upper element. The handling unit 18a is implemented as a robotic handler.

[0096] By applying the upper element onto an upper element contact surface 58a of the footwear last 10a a shape of the upper element can be defined. The upper element contact surface 58a refers to a surface of the footwear last 10a on which the upper element rests after being applied to the footwear last 10a.

[0097] ONA-21576-P-WOOn Clouds GmbH 13 / 22

[0098] The footwear last 10a comprises a footwear part contact surface 64a. The upper element contact surface 58a is part of the footwear part contact surface 64a. The footwear part contact surface 64a refers to a surface of the footwear last 10a on which the footwear part, i.e. the upper element and the midsole element 40a, rests after being manufactured and before being separated from the footwear last 10a, for example by means of the handling unit 18a and / or manually.

[0099] The footwear last 10a is detachably connected to the midsole element 40a prior to applying the filament F to the footwear last 10a to form the upper element. The midsole element 40a is for example mechanically, magnetically, adhesively, electrostatically, by a negative pressure, a combination thereof, or the like, detachably held at the footwear last 10a, in particular on a midsole contact surface 66a of the footwear last 10a. The midsole contact surface 66a is part of the footwear part contact surface 64a and refers to a surface of the footwear last 10a on which the midsole element 40a rests when attached to the footwear last 10a at least during manufacturing, in particular during the application of the thermoplastic filament F for forming the upper element. The handling unit 18a is also configured to move the footwear last 10a during the manufacturing process between different manufacturing stations of the manufacturing system 32a. The filament output unit 38a is one such manufacturing station.

[0100] The filament output unit 38a is configured for applying at least part of the upper element onto the midsole element 40a to connect the upper element to the midsole element 40a.

[0101] The manufacturing system 28a comprises a heating chamber 62a. The heating chamber 62a is one of the previously mentioned manufacturing stations of the manufacturing system 32a. A printer unit to apply a print to the footwear part and / or a plasma unit to treat the footwear part are possible further manufacturing stations of the manufacturing system 32a (not shown here). The heating chamber 62a is configured to heat the footwear last 10a and / or the midsole element 40a prior to application of the upper element onto the midsole element 40a and the footwear last 10a.

[0102] The manufacturing system 32a comprises a direct heat unit 60a for heating the midsole element 40a prior and / or while applying the upper element onto the footwear last 10a by a direct heat input. This allows the midsole element 40a to be heated both in the heating chamber 62a and by the direct heat unit 60a. For example, the midsole element 40a can first be heated in the heating chamber 62a and then specifically with the direct heat unit 60a. The manufacturing system 32a may also be implemented solely with the heating chamber 62a or the direct heat unit 60a.

[0103] The heating of the midsole element 40a in the heating chamber 62a and / or by direct heat input through the direct heat unit 60a may soften and / or melt at least sections of the ONA-21576-P-WOOn Clouds GmbH 14 / 22

[0104] midsole element 40a for connecting the upper element to the midsole element 40a when the upper element is applied onto the footwear last 10a.

[0105] The direct heat input is provided by irradiation, in particular at least partially electromagnetic radiation. Thus, the direct heat unit 60a comprises an irradiation unit. The irradiation unit comprises a laser unit to provide laser light. Alternatively, or additionally, the electromagnetic radiation may comprise microwave radiation. Additionally or alternatively, the irradiation unit may also comprise an acoustic unit for providing acoustic radiation for heating the midsole element 40a, in particular by ultrasound.

[0106] The footwear last 10a comprises a mid- and forefoot section 12a and a hindfoot section 14a. The hindfoot section has an interface 16a for connecting to the handling unit 18a. The mid- and forefoot section 12a comprises a midfoot section that represents a midfoot of a foot and a forefoot section that represents a forefoot of a foot. The hindfoot section 14a represents a hindfoot of a foot.

[0107] The mid- and forefoot section 12a comprises a cavity 20a (cf. Figure 2). The cavity 20a is a free, unfilled space. The cavity 20a is an internal cavity. The cavity 20a is different from a material guiding channel, a heating channel, a cooling channel, or the like. The cavity 20a is primarily present for weight reduction.

[0108] The mid- and forefoot section 12a is essentially hollow, wherein at least 75 % of the mid- and forefoot section 12a in relation to a whole volume of the mid- and forefoot section 12a is a free, unfilled space, which is provided by the cavity 20a.

[0109] The hindfoot section 14a comprises a cavity 22a. The cavity 22a and the cavity 20a form a continuous cavity. The hindfoot section 14a is essentially hollow, wherein at least 75 % of the hindfoot section 14a in relation to a whole volume of the hindfoot section 14a is a free, unfilled space, which is provided by the cavity 22a.

[0110] The mid- and forefoot section 12a and the hindfoot section 14a are rigid. The mid-and forefoot section 12a and the hindfoot section 14a are formed such that they do not deform at least during the manufacture of the footwear part. The entire footwear last 10a is rigid. The mid- and forefoot section 12a and the hindfoot section 14a are formed in one piece.

[0111] The mid- and forefoot section 12a and the hindfoot section 14a are made from a metal, in particular from aluminum. Alternatively, the mid- and forefoot section 12a and / or the hindfoot section 14a may be made from another metal, and / or any other applicable material.

[0112] Figure 3 shows a schematic sequence of a method for manufacturing the footwear part by using the footwear last 10a in the manufacturing system 32a.

[0113] ONA-21576-P-WOOn Clouds GmbH 15 / 22

[0114] In a step 68a of the method, the handling unit 18a connects to the footwear last 10a for conveying the footwear last 10a between the various manufacturing stations of the manufacturing system 32a.

[0115] In a step 70a, the midsole element 40a is connected to the footwear last 10a by means of the handling unit 18a and / or manually.

[0116] In a heating step 72a, the footwear last 10a and the attached midsole element 40a are transported to the heating chamber 62a by means of the handling unit 18a and are heated in the heating chamber 62a. Alternatively it may be envisaged that only the footwear last 10a or only the midsole element 40a are heated in the heating chamber 62a.

[0117] The method comprises a transport step 34a of moving the footwear last 10a with the attached midsole element 40a to the filament output unit 38 using the handling unit 18a.

[0118] In a step, in particular in a further heating step 74a, the midsole element 40a is heated by direct heat input, in particular via the direct heat unit 60a. The direct heat unit 60a heats an upper edge area of the midsole element 40a, onto which the upper element is then applied for connection. By heating the upper edge area of the midsole element 40a, the midsole element 40a is intended to be softened and / or melted for bonding with the upper element. The handling unit 18a moves the footwear last 10a and thus, the midsole element 40a relative to the direct heat unit 60a in such a way that the upper edge area of the midsole element 40a is heated.

[0119] In a step, in particular in an application step 36a, the upper element is shaped on the footwear last 10a by the application of the thermoplastic filament F. Herein, the upper element is connected to the midsole element 40a. Connecting the upper element to the midsole element 40a is performed while shaping the upper element. For this purpose, the filament F is applied also onto the midsole element 40a, in particular onto the upper edge area of the midsole element 40a, for connecting the upper element to the midsole element 40a. The upper element is shaped on the footwear last 10a by applying the thermoplastic filament F onto the footwear last 10a to form the plurality of path segments, in particular intersecting loops, on the footwear last 10a along the application path P.

[0120] In a step, in particular a print step 76a, a print is applied to the footwear part and the footwear part is treated via a plasma unit (not shown here).

[0121] In a step, in particular a detaching step 78a, the footwear part is automatically removed from the footwear last 10a by means of the handling unit 18a or manually removed from the footwear last 10a.

[0122] Figures 4 to 8 show further embodiments of the invention. The following description and drawings are essentially limited to the differences between the embodiments, whereby reference can in principle also be made to the drawings and / or description of the other embodiments, in particular to Figure 1 to Figure 3, with regard to components with the same ONA-21576-P-WOOn Clouds GmbH 16 / 22

[0123] designation, in particular with regard to components with the same reference signs. To differentiate between the embodiments, the letter “a” is placed after the reference signs of the embodiment of Figure 1 to Figure 3. In the embodiments of Figures 4 to 8, the letter “a” is replaced by the letters “b”, “c”, “d”, and “e”.

[0124] Figure 4 shows a footwear last 10b comprising a mid- and forefoot section 12b and a hindfoot section 14b. The hindfoot section 14b has an interface 16b for connecting to a handling unit.

[0125] The mid- and forefoot section 12b comprises a cavity 20b such that the mid- and forefoot section 12b is essentially hollow. The hindfoot section 14b comprises a cavity 22b such that the hindfoot section 14b is essentially hollow. The cavities 20b, 22b form a continuous cavity.

[0126] The mid- and forefoot section 12b and the hindfoot section 14b are open at a bottom side 24b of the footwear last 10b (cf. Figure 5). The mid- and forefoot section 12b and hindfoot section 14b are open to at least 75 % at the bottom side 24b of the footwear last 10b. The bottom side 24b corresponds to a sole section of the footwear last 10b. The open bottom side 24b of the footwear last 10b is closed by the midsole element 40b when the midsole element 40b is attached to the footwear last 10b.

[0127] The footwear last 12b comprises three reinforcement elements 26b, 28b. Alternatively, the footwear last 12b may comprise one, two, more than three, or no reinforcement elements 26, 28b. A reinforcement element 26b of the three reinforcement elements 26b, 28b extends over both cavities 20b, 22b. Two further reinforcement elements 28b of the three reinforcement elements 26b, 28b are arranged in the cavity 20b of the mid-and forefoot section 12b.

[0128] The three reinforcement elements 26b, 28b are formed as reinforcement struts. The reinforcement element 26b is arranged in a longitudinal direction of the footwear last 10b. The two further reinforcement elements 28b are arranged in a transverse direction of the footwear last 10b, in particular perpendicular to the reinforcement element 26b. The further reinforcement elements 28b are fixed to the reinforcement element 26b. The three reinforcement elements are firmly connected to the mid- and forefoot section 12b and / or the hindfoot section 14b, in particular by a welded connection.

[0129] One, some, or all of the reinforcement elements 26b, 28b may comprise attachment points for attaching and / or receptacles for receiving magnetic elements of the footwear last 10b (not shown). These magnetic elements may be configured for holding a sole unit and / or additional shaping elements of the footwear last 10b (also not shown) during application of a thermoplastic filament onto the footwear last 10b.

[0130] ONA-21576-P-WOOn Clouds GmbH 17 / 22

[0131] The footwear last 10b, in particular the mid- and forefoot section 12b and the hindfoot section 14b, are made entirely from a non-porous plastic, for example from high-density polyethylene.

[0132] Figure 6 shows a footwear last 10c comprising a mid- and forefoot section 12c and a hindfoot section 14c. The hindfoot section 14c has an interface 16c for connecting to a handling unit. The mid- and forefoot section 12c comprises a cavity 20c such that the mid-and forefoot section 12c is essentially hollow.

[0133] The hindfoot section 14c has a higher density than the mid- and forefoot section 12c. The hindfoot section 14c is made from a solid homogeneous material, i.e. is formed free from cavities.

[0134] A center of mass of the footwear last 10c is closer to a handling axis 30c defined by the interface 16c compared to a comparative footwear last made from a solid homogeneous material.

[0135] The footwear last 10c comprises a reinforcement element 32c formed as a reinforcement rib. The reinforcement element 32c is integrally formed, i.e. formed in one piece with the mid- and forefoot section 12c.

[0136] Figure 7 shows a footwear last 10d comprising a mid- and forefoot section 12d and a hindfoot section 14d. The hindfoot section 14d has an interface 16d for connecting to a handling unit.

[0137] The mid- and forefoot section 12d and the hindfoot section 14b comprise a multitude of cavities (not shown here). The mid- and forefoot section 12d and the hindfoot section 14d are made from a porous material except for the interface 16d. The cavities of the mid- and forefoot section 12d and the hindfoot section 14b are provided by manufacturing the mid-and forefoot section 12d and the hindfoot section 14b from the porous material. The porous material is expanded polystyrene.

[0138] Figure 8 shows a footwear last 10e comprising a mid- and forefoot section 12e and a hindfoot section 14e. The hindfoot section 14e has an interface 16e for connecting to a handling unit.

[0139] The hindfoot section 14e has a higher density than the mid- and forefoot section 12e. The mid- and forefoot section 12e and the hindfoot section 14e are made from different materials. The mid- and forefoot section 12e is made from a porous material and the hindfoot section is made from a non-porous plastic.

[0140] A center of mass of the footwear last 10e is closer to a handling axis 30e defined by the interface 16e compared to a comparative footwear last entirely made from a solid homogeneous material.

[0141] The mid- and forefoot section 12e and the hindfoot section 14e are detachably connected to each other. The mid- and forefoot section 12e and / or the hindfoot section 14e ONA-21576-P-WOOn Clouds GmbH 18 / 22

[0142] can be exchanged with various other mid- and forefoot sections and other hindfoot sections respectively, having different material compositions, densities, weights, sizes, or the like. The mid- and forefoot section 12e and the hindfoot section 14e have corresponding latching elements (not shown here) for a detachable connection to each other. Alternatively or additionally, the mid- and forefoot section 12e and the hindfoot section 14e may be detachably connected via a screw connection, a clamp connection, or the like.

[0143] Various modifications to the embodiments described are possible and will occur to those skilled in the art without departing from the invention, which is defined by the following claims.

[0144] List of reference symbols

[0145] 10 footwear last

[0146] 12 mid- and forefoot section

[0147] 14 hindfoot section

[0148] 16 interface

[0149] 18 handling unit

[0150] 20 cavity

[0151] 22 cavity

[0152] 24 bottom side

[0153] 26 reinforcement element

[0154] 28 reinforcement element

[0155] 30 handling axis

[0156] 32 manufacturing system

[0157] 34 transport step

[0158] 36 application step

[0159] 38 filament output unit

[0160] 40 midsole element

[0161] 42 dosing unit

[0162] 44 melting unit

[0163] 46 nozzle unit

[0164] 48 barrel

[0165] 50 screw

[0166] 52 pump

[0167] ONA-21576-P-WOOn Clouds GmbH

[0168] 19 / 22 54 pump drive

[0169] 56 dosing head

[0170] 58 upper element contact surface 60 direct heat unit

[0171] 62 heating chamber

[0172] 64 footwear part contact surface 66 midsole contact surface

[0173] 68 step

[0174] 70 step

[0175] 72 heating step

[0176] 74 heating step

[0177] F thermoplastic filament

[0178] P application path

[0179] ONA-21576-P-WO

Claims

On Clouds GmbH 20 / 22Claims1. A footwear last (1 Oa-e) for manufacturing a footwear part, comprising:- a mid- and forefoot section (12a-e); and- a hindfoot section (14a-e) having an interface (16a-e) for connecting to a handling unit (18a),characterized in thatthe mid- and forefoot section (14a-d) comprises at least one cavity (20a-c).

2. The footwear last (1 Oa-c) according to claim 1 ,wherein the mid- and forefoot section (12a-c) is essentially hollow.

3. The footwear last (10a; 10b; 10d) according to claim 1 or 2,wherein the hindfoot section (14a; 14b; 14d) comprises at least one cavity (22a; 22b).

4. The footwear last (10a; 10b) according to claim 3,wherein the hindfoot section (14a; 14b) is essentially hollow.

5. The footwear last (10b) according to any one of the preceding claims, wherein the mid- and forefoot section (12b) and / or the hindfoot section (14b) are / is at least partially open at a bottom side (24b).

6. The footwear last (10a-e) according to any one of the preceding claims, wherein the mid- and forefoot section (12a-e) and / or the hindfoot section (14a-e) are / is rigid.

7. The footwear last (10b; 10c) according to any one of the preceding claims, further comprising:- at least one reinforcement element (26b, 28b; 26c) arranged in the at least one cavity (20b, 22b; 20c).

8. The footwear last (10a) according to any one of the preceding claims, wherein the mid- and forefoot section (12a) and / or the hindfoot section (14a) are / is at least partially made from a metal.

9. The footwear last (10d) according to any one of the preceding claims, wherein the mid- and forefoot section (12d) and / or the hindfoot section (14d) are / is made at least partially from a porous material.

10. The footwear last (10c; 10e) at least according to the preamble of claim 1, in particular according to any one of the preceding claims,wherein the hindfoot section (14c; 14e) has a higher density than the mid- and forefoot section (12c; 12e).

11. The footwear last (1 Oe) according to any one of the preceding claims, wherein the mid- and forefoot section (12e) and the hindfoot section (14e) are at least partially made from different materials.ONA-21576-P-WOOn Clouds GmbH 21 / 2212. The footwear last (10c; 10e) according to any one of the preceding claims, wherein a center of mass of the footwear last (10c; 10e) is closer to a handling axis (30c; 30e) defined by the interface (16c, 16e) compared to a comparative footwear last made from a solid homogeneous material.

13. A manufacturing system (32a) for manufacturing a footwear part, comprising:- a footwear last (10a-e) according to any one of the preceding claims; and- a handling unit (18a) attached to the interface (16a-e).

14. A method for manufacturing a footwear part by using a footwear last (10a-e) according to any one of the claims 1 to 12 in a manufacturing system (32a) according to claim 13.

15. The method according to claim 14, comprising:- a transport step (34a) of moving the footwear last (10a-e) relative to a filament output unit (38a) of the manufacturing system (32a) using the handling unit (18a); and- an application step (36a) of applying at least one thermoplastic filament (F) onto the footwear last (10a-e) to form a plurality of path segments, in particular loops, on the footwear last (10a-e) along an application path (P) for forming at least one footwear element of the footwear part.ONA-21576-P-WO

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