Skinned cell structure and method for manufacturing a skinned cell structure - Patents.com

Abstract

To provide an apparatus and method for producing skinned cell structures.SOLUTION: The device includes a placer to place foamable structures together to define a bundle, a restrainer to restrain the bundle, an activator to activate the foamable structures to expand and form a cell structure within the restrainer, a trimmer to trim the cell structure to define a core, and an assembler to couple a skin to the core to define the skinned cell structure.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE

[0001] This disclosure relates generally to laminated composites, and more particularly to skinned cellular structures and methods of making skinned cellular structures. [Background technology]

[0002]

[0002] In recent years, laminated composites (e.g., laminated composite structures) have become more frequently used due to their favorable stiffness-to-weight ratio combined with relatively low production costs. Laminated composites typically include at least two different material layers bonded together and are commonly implemented for aircraft component applications such as rudders, ailerons, spoilers, and flaps. Summary of the Invention

[0003]

[0003] An exemplary apparatus includes a placer for placing the foamable structures together to define a bundle, and a restrainer for restraining the bundle. The exemplary apparatus also includes an activator for adding an activator to the foamable structures to form a cellular structure within the restrainer. The exemplary apparatus further includes a trimmer for trimming the cellular structure to define a core, and an assembler for bonding the core to the skins.

[0004]

[0004] An exemplary method of making a skinned cellular structure includes attaching foam structures together to define a bundle and constraining the bundle. The exemplary method further includes adding an activator to the foam structures of the bundle to define the cellular structure. The exemplary method further includes arranging the cellular structure to define a core and assembling the core to a skin to define the skinned cellular structure.

[0005]

[0005] An exemplary skinned cellular structure includes a core having cells defined by a bundled, restrained, and activated foam structure via an activator. The exemplary skinned cellular structure further includes a skin bonded to at least one surface of the core. [Brief description of the drawings]

[0006] [Figure 1]

[0006] An exemplary process for manufacturing a skinned cell structure according to the teachings of the present disclosure is shown. [Diagram 2]

[0007] 1 is a schematic representation of an exemplary skinned cell structure manufacturing system for producing embodiments of the present disclosure. [Diagram 3]

[0008] 1 illustrates an exemplary restraint that may be implemented within embodiments of the present disclosure. [Figure 4A]

[0009] 4A-4D illustrate an exemplary skinned cell structure in accordance with the teachings of the present disclosure. [Figure 4B] 4A-4D illustrate an exemplary skinned cell structure in accordance with the teachings of the present disclosure. [Figure 4C] 4A-4D illustrate an exemplary skinned cell structure in accordance with the teachings of the present disclosure. [Figure 4D] 4A-4D illustrate an exemplary skinned cell structure in accordance with the teachings of the present disclosure. [Diagram 5]

[0010] 1 is a flow chart illustrating an exemplary method for manufacturing embodiments disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007]

[0011] The drawings are not to scale. Instead, the thickness of layers or regions may be exaggerated in the drawings. In general, the same reference numbers will be used for identical or similar parts throughout the drawing(s) and the accompanying description. As used in this patent application, a statement that any part is on (e.g., disposed on, located on, mounted on, formed on, etc.) another part in any manner means that the part referred to is either in contact with the other part or that the part referred to is on top of the other part with (one or more) intermediate part(s) between them. Connection references (e.g., attached, coupled, connected, and joined) should be interpreted broadly and, unless otherwise expressly stated, may include intermediate members between groups of elements and include relative movement between the elements. As such, connection references do not necessarily mean that two elements are directly connected and in a fixed relationship with respect to each other. A statement that any part is "in contact with" another part means that there are no intermediate parts between the two parts.

[0008]

[0012] Descriptions such as "first," "second," and "third" are used herein when identifying multiple elements or components that may be referenced individually. Unless otherwise specified or apparent based on the context of their use, such descriptions are not intended to imply any sense of priority, physical order, or arrangement in a list, or chronological order, but are used merely as labels to refer to multiple elements or components individually to facilitate understanding of the disclosed examples. In some embodiments, the description "first" may be used to refer to an element in the detailed description, but the same element may be referred to in the claims with a different description, such as "second" or "third." In such instances, it should be understood that these descriptions are used merely to facilitate reference to multiple elements or components.

[0009]

[0013] Skinned cellular structures and methods of manufacturing skinned cellular structures are disclosed. In known implementations, laminated composites (e.g., laminated composite structures) are typically implemented in aircraft due to their favorable strength characteristics. In particular, laminated composites are relatively lightweight, yet nevertheless exhibit a relatively high amount of structural strength. However, these known implementations can be expensive to manufacture and repair.

[0010]

[0014] Examples of the present disclosure enable cost-effective, high-strength, lightweight skinned cell structures. Examples of the present disclosure may also be rapidly manufactured for implementation in a manufacturing environment and / or for field repair (e.g., replacement of parts and / or sections for existing aircraft). Additionally, examples of the present disclosure may enable the manufacture of components having relatively complex shapes and / or dimensions. Additionally or alternatively, examples of the present disclosure may be used for thermal and acoustic insulation.

[0011]

[0015] The embodiments disclosed herein include a cellular structure core that is at least partially covered (e.g., completely covered) by a skin (e.g., a protective outer skin, an exterior skin surface, a carbon fiber skin, etc.). The cellular structure is formed by activating a foamable structure (e.g., pellets, rods, etc.) with an activator (e.g., a heat activator, a chemical activator, application of an electric current, an electrical substance, etc.) provided by an activator. In particular, the foamable structure is attached (e.g., bound together) by an attachment device and constrained (e.g., force constrained, encapsulated, elastically constrained, rigidly constrained, etc.) by a restrainer for activation. During activation, the foamable structure expands to define the cellular structure. Once formed, the cellular structure is trimmed and / or cut (e.g., machine cut, cut into layers, etc.) to define the core. The core can be a prismatic block, a laminated block, a contoured block, a core piece, a trimmed layer, etc. Additionally, the core is bonded and / or joined to said skins to define a skinned cellular structure.

[0012]

[0016] In some embodiments, the core comprises a fiber reinforced foam honeycomb material. Additionally or alternatively, the skins comprise prepregs or pre-cured components. In some embodiments, the foamable structure (e.g., pellets, rods, etc.) is formed by an extruder or pultruder. Additionally or alternatively, the foamable structure may be at least partially comprised of a fiber reinforced material. In some embodiments, the restrainer comprises a bladder for elastically restraining the bundled foamable structure during its expansion caused by the activation process. In some embodiments, the skins and core are co-cured in an oven and / or autoclave.

[0013]

[0017] As used herein, the term "expandable structure" refers to discrete material portions (e.g., pellets, rods, granules, solid structures, etc.) that are attached together (e.g., stacked side-by-side, bundled together) and activated to define relatively continuous cells of a cellular structure. As used herein, the term "bundled" refers to the aforementioned material portions being closely attached and / or brought into contact with each other (e.g., stacked, bundled, assembled, etc.) prior to activation. As used herein, the term "cellular structure" refers to a structure that at least partially resembles a cellular pattern (e.g., honeycomb pattern, closed cell pattern, etc.) formed from the activation of at least one expandable structure. As used herein, the term "core" refers to the aforementioned cellular structure that is bonded to a skin. Thus, the cellular structure may be shaped, trimmed, and / or cut to define a core that is bonded to the skin. As used herein, the term "skin" refers to a surface, wall, and / or contour attached to a core and / or cell structure to at least partially define its exterior (e.g., outer surface, outer wall, etc.). As used herein, the term "bladder" refers to an expandable structure, assembly, membrane, and / or component.

[0014]

[0018] FIG. 1 illustrates an exemplary process 100 for manufacturing a skinned cellular structure according to the teachings of the present disclosure. In one exemplary embodiment, an exemplary forming step 101 illustrates an expandable structure 102 after a forming process (e.g., extrusion, pultrusion, etc.). In this particular embodiment, the expandable structure 102 is extruded to have a generally circular cross-sectional profile along a respective longitudinal axis 104. However, in other embodiments, the expandable structure 102 may be extruded to have any other suitable cross-sectional profile, including, but not limited to, a rectangular profile, a triangular profile, a polygonal profile, etc. Additionally or alternatively, the expandable structure 102 is formed as pellets and / or granules. In some embodiments, the amount, size, density, and / or shape of the expandable structure 102 are varied based on the desired properties of the resulting cellular structure. In some embodiments, the expandable material includes and / or is at least partially composed of a thermoplastic resin.

[0015]

[0019] In an exemplary constraining step 106, the foamable structures 102 are attached (e.g., bundled, stacked side-by-side, arranged, patterned, etc.) in contact with one another, thereby defining bundles 108. The foamable structures 102 may be arranged in an interwoven or staggered configuration, for example. In some embodiments, the foamable structures 102 are stacked side-by-side and / or arranged in a grid and / or lattice pattern. In this embodiment, the foamable structures 102 are attached in contact with one another. However, in other embodiments, the bundles 108 include a combination of foamable structures 102 and structural rods (e.g., metal rods, thermoplastic rods, hollow rods, thermoset rods, hollow glass beads, etc.). In some embodiments, the structural rods are generally solid (e.g., do not include internal voids or openings) with the foamable structures 102 attached between the structural rods. Additionally or alternatively, the foamable structure 102 may be attached inside an interior opening (e.g., a hollow opening) of a structural rod for subsequent activation. In some embodiments, the hollow structural rod acts as a restrainer. Additionally or alternatively, a skin is attached in contact with a metal rod and is provided with heat energy and / or electrical current / electricity from the metal rod (e.g., to harden the skin into an activated foamable structure).

[0016]

[0020] In an exemplary activation step 110, the foamable structure 102 is activated (e.g., thermally, electrically, and / or chemically activated) with an activator provided by an activator 208 (shown in FIG. 2 ) to define individual cells (e.g., activated foamable structure) 112 and thus cellular structures (e.g., a cellular grid, honeycomb pattern, cellular pattern, etc.) 114. In this example, the foamable structure 102 expands, bonds, and / or adheres to one another during its activation. Although the cells 112 are generally depicted as approximately hexagonal in this example, the cells 112 may be any suitable cell shape and / or pattern based on the relative placement of the foamable structure 102 within the bundle 108 and / or various activation process parameters.

[0017]

[0021] An exemplary conditioning step 116 corresponds to trimming and / or cutting (e.g., machine cut, sliced, laser cut, etc.) the cellular structure 114 around cut lines 118 to define at least one distinguishable core (e.g., core piece, core layer, trimmed core, etc.) 120. In this example, the core 120 is generally depicted as a layer. However, in other examples, the core 120 may be trimmed and / or cut into any other suitable shape. For example, the cellular structure 114 may be cut (e.g., machine, etched, water jet cut, etc.) along multiple directions (e.g., 3D cuts) to form relatively complex geometries (e.g., curved surfaces, openings, contours, etc.) of the core 120. In some other examples, the core is defined by an activation process (e.g., the core is not trimmed and / or trimmed).

[0018]

[0022] In an exemplary assembly step 125, the core 120 is shown being bonded, attached, assembled, and / or joined to a skin (e.g., a carbon fiber skin, an elastomeric skin, etc.) 126 to define a skinned cell structure 124. In this embodiment, the skin 126 has a corresponding surface 128 that at least partially covers the core 120. In an exemplary embodiment, the skin 126 does not cover at least a portion or side 130 of the core 120. However, in some other embodiments, the skin 126 generally surrounds (e.g., encases) all sides and / or surfaces of the core 120. In this embodiment, once the core 120 is bonded to the skin 126, the core 120 and the skin 126 are cured with a heating process. In some embodiments, a bonding layer (e.g., an attachment layer, an applied adhesive layer, an epoxy layer, etc.) 132 bonds the core 120 to the skin 126.

[0019]

[0023] 2 is a schematic representation of an exemplary skinned cellular structure manufacturing system 200 for manufacturing embodiments of the present disclosure. The illustrated embodiment skinned cellular structure manufacturing system 200 includes a former 202, an attachment 204, a restrainer 206, the aforementioned activator 208, a conditioner 210, an assembler 212, and a curer 214. In some embodiments, the former 202, the attachment 204, the restrainer 206, the activator 208, the conditioner 210, the assembler 212, and / or the curer 214 are part of a single process and / or apparatus.

[0020]

[0024] To form and / or produce the expandable structure 102, the example former 202 applies a forming process (e.g., extrusion process, pultrusion process, etc.) to a expandable medium (e.g., slurry, dry medium, etc.), thereby producing a structure (e.g., pellets, rods, tubes, etc.) for subsequent activation (e.g., foam activation). In some other embodiments, the former 202 is implemented as a pelletizer system. In some such embodiments, the pelletized medium and / or structure may be bonded together during a bonding process to define the expandable structure 102.

[0021]

[0025] To define the bundle 108 shown in FIG. 1 , a fixture 204 defines an array (e.g., a lattice) of the foamable structures 102 by attaching and / or arranging the foamable structures 102 together. In some embodiments, the fixture 204 stacks the foamable structures 102 side-by-side so that the foamable structures 102 contact each other (e.g., in a lattice pattern or woven configuration) to more efficiently form a closed cellular structure once the foamable structures 102 are activated. In some embodiments, a reinforcement material, such as, for example, a laminate composite layer, is attached within the bundle 108. In some such embodiments, the reinforcement material may provide structural support to the resulting cellular structure.

[0022]

[0026] To restrain the foamable structure 102 prior to activation, an exemplary restrainer 206 is positioned to encase and / or partially surround the foamable structure 102 and / or bundles 108. In particular, the restrainer 206 elastically expands with the foamable structure 102 during activation. Alternatively, the restrainer 206 may be implemented to rigidly restrain the foamable structure 102.

[0023]

[0027] To form the cellular structure 114, the activator 208 applies an activator to the foamable structure 102 while the foamable structure is held and / or constrained by the constrainer 206. The activator causes the foamable structure 102 in the bundle 108 to expand and bond (e.g., coalesce, sinter, etc.), thereby forming the cellular structure 114. In some embodiments, the activator includes thermal energy generated or provided by an oven or other suitable thermal energy source. Additionally or alternatively, the activator includes a chemical compound and / or a chemical agent that activates the foamable structure 102. In some other embodiments, the activator includes, for example, a current or voltage source (e.g., a generator, an electricity, a voltage source, etc.). In some embodiments, the current or voltage source generates thermal energy (e.g., via an electrical resistance) to activate the foamable structure 102. Additionally or alternatively, in some embodiments, the hardener 214 at least partially activates the foamable structure 102.

[0024]

[0028] In an example embodiment, conditioner 210 cuts and / or divides (e.g., subdivides) cellular structure 114 to define at least one of cores 120 (e.g., cellular structure 114 is subdivided into multiple ones of cores 120). In some embodiments, cellular structure 114 is cut and / or trimmed into a single one of cores 120 that is then coupled to skin 126. In some other embodiments, cellular structure 114 is not cut and / or trimmed.

[0025]

[0029] To bond the skin 126 to the core 120, the assembler 212 of the illustrated embodiment is implemented to place the skin 126 and the core 120 in contact with one another and add and / or define a bonding layer 132 therebetween. In some embodiments, the assembler 212 places the core 120 and the skin 126 in a vacuum bag after they are adhesively bonded to one another (via structural attachment). In this embodiment, bonding the skin 126 to the core 120 via the bonding layer 132 defines a skinned cell structure 124.

[0026]

[0030] In some embodiments, a curing machine 214 solidifies the bonding layer 132 between the skin 126 and the core 120 to define the skinned cell structure 124. The curing machine 214 may be implemented as an oven or an autoclave. In some such embodiments, the skin 126 may be at least partially cured on at least one side of the core 120.

[0027]

[0031] 3 illustrates an exemplary restrainer 206 that may be implemented within the embodiments disclosed herein. The restrainer 206 is for constraining and / or restraining the bundle 108 during activation of the foamable structure 102. In the exemplary embodiment, the restrainer 206 includes end stops 302 on either side of the restrainer 206, a flow path (e.g., tube, pipe, container, channel, etc.) 304, an opening (e.g., vent, slit, etc.) 306, and a bladder (e.g., elastic bladder, etc.) 308. In the illustrated view of FIG. 3, the bundle 108 is shown disposed within the exemplary restrainer 206.

[0028]

[0032] The exemplary bladder 308 is implemented to constrain (e.g., elastically constrain) and hold the foamable structure 102 together as it expands during activation. In this embodiment, the bladder 308 expands with the foamable structure 102 during activation, but provides a constraining force to the foamable structure 102. In particular, the exemplary bladder 308 constrains the foamable structure 102 to generally maintain the relative configuration of the bundles 108 and ensure that the foamable structure 102 is held with sufficient pressure, thereby causing the foamable structure 102 to expand into a relatively ordered cellular pattern. In some embodiments, the relatively small constraining force provided by the bladder 308 promotes adhesion of the foamable structure 102 during and after the activation process. In other embodiments, the bladder 308 has different elasticity at various locations, resulting in locally different expansion of the foamable structure 102 and therefore a variable density across the resulting cellular structure. In other embodiments, a rigid container is implemented in place of the bladder 308.

[0029]

[0033] In certain embodiments, the flow path 304 provides the aforementioned activating agent to the reservoir 206 and then to the expandable structure 102. In the illustrated embodiment, the flow path 304 is implemented as a tube (e.g., an elastic tube, a rigid tube, a conduit, etc.) that is fluidly coupled and sealed to the restrainer 206. In some such embodiments, an opening 306 may be implemented to allow gas by-products from the activation process to exit the restrainer 206. In some other embodiments, the flow path 304 is not implemented. In some such embodiments, the activating agent migrates from the activator 208 through the bladder 308 and thus to the expandable structure 102 (e.g., the bladder 308 is at least semi-permeable).

[0030]

[0034] In some embodiments, end stops 302 are implemented to reduce (e.g., prevent) expansion of the foam structure 102 along the length of the restrainer 206. In particular, the exemplary end stops 302 may be rigid or resilient and contact (e.g., border, cover, etc.) at least one longitudinal end of the bundle 108 to restrain the longitudinal end. In other embodiments, only one end cap 302 is implemented. Additionally or alternatively, the end stops 302 laterally restrain the foam structure 102 (e.g., restrain at least a side of the foam structure 102).

[0031]

[0035] In some embodiments, two or more restrainers 206 are stacked side-by-side (e.g., adjacent side-by-side, vertical side-by-side, concentric side-by-side, etc.) to vary the size of the cell(s) 112 and thus the density of the cellular structure 114 in various areas (e.g., to define density variations, local variations, and / or gradients). In some such embodiments, the density of the resulting core 120 may be increased at edges, attachment points, build-ups, bond areas / points, etc.

[0032]

[0036] Additionally or alternatively, the restrainer(s) 206 at least partially define the desired shape of the core 120, followed by the cellular structure 114 being bonded to the skin 126 after activation of the expandable structure 102. In some other embodiments, the restrainer 206 defines and / or forms the skin 126. In such embodiments, the restrainer 206 remains at least partially bonded to the cellular structure 114 after activation of the expandable structure 102, and thus becomes the skin 126 after the activation process. In some embodiments, the restrainer 206 comprises a thermoplastic material. The thermoplastic material may be burned off and / or decomposed during or after the activation process.

[0033]

[0037] 4A-4D illustrate an exemplary skinned cellular structure according to the teachings of the present disclosure. Referring to FIG. 4A, an exemplary skinned cellular structure 124 is shown in which the core 120 has a relatively uniform density. In one exemplary embodiment, the skinned cellular structure 124 includes the aforementioned core 120 bonded to the skin 126 via a bonding layer (e.g., adhesive bonding layer) 132, which may be implemented as a chemical fastener and / or adhesive. In other words, the bonding layer 132 is disposed between the skin 126 and the core 120. In other embodiments, mechanical fastener(s) (e.g., screws, rivets, etc.) are implemented instead.

[0034]

[0038] In the illustrated embodiment, at least one of the surfaces 128 exhibits curvature while the other of the surfaces 128 is relatively flat. In particular, the skin 126 is continuous, with a first portion 402 of the skin 126 attached to a curved portion and / or surface of the core 120 while a second portion 404 of the skin 126 is attached to a relatively flat surface of the core 120. Additionally or alternatively, the first and second portions 402, 404 of the skin 126 are separate and bonded separately during separate bonding steps or in a single bonding step. In some embodiments, at least a portion of the skin 126 and / or the core 120 is cut away to expose at least one interior surface of the core 120.

[0035]

[0039] In this example, the core 120 includes an exposed side 130 that may be attached adjacent to an exposed non-exterior surface of another component (e.g., during a field repair). In some examples, multiple ones of the skinned cellular structures 124 are bonded to their respective exposed surfaces 130 to form a single part. In some other examples, the core 120 is completely surrounded (e.g., completely encased, completely enclosed, etc.) by the skin 126.

[0036]

[0040] 4B illustrates an exemplary skinned cellular structure 410 having a composite core 411 with cores 412, 414, 416 of varying density in various regions. In one exemplary embodiment, the varying density of the core 411 allows the skinned cellular structure 410 to exhibit different strengths and flexibility based on the loading conditions (e.g., location of the applied load). In some embodiments, the cores (e.g., core regions) 412, 414, 416 are formed during a single activation step (e.g., using side-by-side stacks of the restrainers 206 and / or varying elasticity along various sections of the bladder 308). In other embodiments, the cores 412, 414, 416 are formed during separate activation steps and then side-by-side stacked and / or bonded together to define the core 411.

[0037]

[0041] 4C illustrates an exemplary skinned cellular structure 420 with a reinforcement 422 implemented within the core 424. In some embodiments, the reinforcement 422 comprises a laminated composite and / or metal structure that provides structural support to the skinned cellular structure 420. In some embodiments, the reinforcement 422 is mounted within and surrounded by the foamable structure 102 prior to the activation step, thereby causing the core 424 to adhere to the reinforcement 422. In other embodiments, the reinforcement 422 is inserted into an opening in the core 424 and coupled (e.g., bonded, glued, etc.) to the core 424.

[0038]

[0042] 4D illustrates an exemplary skinned cell structure 430 with a reinforcement 432 affixed to a core 434. In this embodiment, the reinforcement 432 is bonded to an exterior surface(s) of the core 434 and / or to the skin 126 (e.g., an interior surface of the skin 126). In some embodiments, the reinforcement 432 is bonded and / or attached onto the skin 126.

[0039]

[0043] 5 is a flow chart illustrating an example method 500 for implementing embodiments disclosed herein. The example method 500 is performed by the skinned cellular structure manufacturing system 200 to manufacture a skinned cellular structure (e.g., the skinned cellular structure 124). In this particular embodiment, the skinned cellular structure is assembled to a surface of an aerodynamic body of an aircraft (e.g., as a section of a wing of the aircraft).

[0040]

[0044] At block 502, a foamed structure (e.g., foamed structure 102) is formed by a former (e.g., former 202). In some embodiments, the foamed structure is formed with fiber reinforcement. In some such embodiments, the fiber reinforcement may be pulled through an extruder. Additionally or alternatively, the fiber reinforcement may be located near or on an exterior surface of the foamed structure. In some embodiments, the foamed structure is extruded into a tubular shape by the extruder.

[0041]

[0045] At block 504, the foam structures are attached together (e.g., arranged together in a patterned array). For example, the foam structures are arranged in an interspersed grid array, whereby hexagonal cell shapes are defined after the activation process. In some embodiments, reinforcements (e.g., reinforcements 422, 432) are attached between the foam structures or in contact with the foam structures (e.g., on the outer surface of the foam structures).

[0042]

[0046] In block 506, the foamable structure is constrained and / or restrained via a restrainer (e.g., restrainer 206). In this embodiment, the foamable structure is held together as a patterned array. In some embodiments, the restrainer includes end stops (e.g., end stops 302) that may be movable (e.g., translatable).

[0043]

[0047] At block 508, the foamable structure is activated via an activator (e.g., activator 208) to define a cellular structure (e.g., cellular structure 114). In this example, the foamable structure expands as a result of the sinter activation process. In some examples, the cellular structure includes a reinforcing member (e.g., reinforcing member 422) disposed therein.

[0044]

[0048] At block 510, the cellular structure is trimmed via a trimmer (e.g., trimmer 210) to define a core (e.g., core 120). In some embodiments, the cellular structure is trimmed into multiple core layers. In some other embodiments, the cellular structure is cut and / or trimmed to define a single core (e.g., a shaped core, a machined core, etc.). In still other embodiments, the cellular structure is not trimmed, thus defining a core.

[0045]

[0049] At block 512, a skin (e.g., skin 126) is coupled and / or assembled to the core via an assembler (e.g., assembler 212) to define a skinned cellular structure (e.g., skinned cellular structure 124). In some embodiments, the assembler adhesively bonds the core and skin together. In other embodiments, the restrainers remain attached to the core and thus function as skins. Additionally or alternatively, reinforcements may be assembled to or within the core.

[0046]

[0050] The skinned cell structure is then mounted in and / or surrounded by an enclosure at block 514. In some embodiments, the enclosure includes a vacuum bag to ensure that the bond between the core and the skins is intact.

[0047]

[0051] At block 516, in some embodiments, the cellular structure is cured (e.g., by curing machine 214). In this embodiment, an oven is utilized to provide heat to the skinned cellular structure, thereby curing the bond layer between the skin and the core. In some embodiments, an autoclave is implemented to solidify the bond layer between the core and the skin.

[0048]

[0052] Exemplary methods, apparatus, systems, and articles of manufacture for manufacturing skinned cellular structures are disclosed herein. Further examples and combinations thereof include the following:

[0049] Clause 1 includes an apparatus for manufacturing a skinned cellular structure, the apparatus including an attachment device for attaching foamable structures together to define a bundle, a restrainer for restraining the bundle, an activator for adding an activator to the foamable structures to form the cellular structure within the restrainer, a conditioner for arranging the cellular structure to define a core, and an assembler for bonding the skins to the core to define the skinned cellular structure.

[0050] Clause 2 comprises the apparatus of clause 1, further comprising a former for extruding or pultruding the foamed structure.

[0051]

[0053] Clause 3 includes the apparatus of clause 1, wherein the foam structure includes a fiber reinforced material.

[0052]

[0054] Clause 4 comprises the apparatus of clause 3, wherein the fiber reinforcement material is positioned adjacent an exterior surface of the foam structure.

[0053]

[0055] Clause 5 comprises the device of clause 1, wherein the restrainer includes end stops at the longitudinal ends of the bundle.

[0054]

[0056] Clause 6 includes the apparatus of clause 1, wherein the restraint includes an elastic bladder for laterally surrounding the bundle.

[0055]

[0057] Clause 7 includes the apparatus of clause 6, wherein the bladder has different elasticities in different portions thereof.

[0056]

[0058] Clause 8 includes the apparatus of clause 1, wherein the activating agent includes at least one of thermal energy, electrical current, or a chemical agent.

[0057]

[0059] Clause 9 comprises the apparatus of clause 1, further comprising a hardener for hardening the skinned cell structure.

[0058]

[0060] Clause 10 includes a method of making a skinned cellular structure, the method including attaching foamed structures together to define a bundle, constraining the bundle, adding an activator to the foamed structures of the bundle to define a cellular structure, arranging the cellular structures to define a core, and assembling the core to a skin to define a skinned cellular structure.

[0059]

[0061] Clause 11 includes the method of clause 10, further including attaching a stiffener within the bundle.

[0060]

[0062] Clause 12 includes the method of clause 10, wherein attaching the foam structures together includes attaching the foam structures as a patterned array.

[0061]

[0063] Clause 13 includes the method of clause 10, wherein the activating agent includes at least one of thermal energy, electrical current, or a chemical agent.

[0062]

[0064] Clause 14 includes the method of clause 10, wherein assembling the core to the skin includes defining a bonding layer between the core and the skin.

[0063]

[0065] Clause 15 includes the method of clause 10, wherein conditioning the cellular structure includes subdividing the cellular structure into layers.

[0064]

[0066] Clause 16 includes the method of clause 11, further including mounting the core and skins in a vacuum bag and curing the core and skins via an oven.

[0065]

[0067] Clause 17 includes a skinned cellular structure including a core including cells defined by a foamable structure bound, restrained, and activated via an activator, the skin being bonded to at least one surface of the core.

[0066]

[0068] Clause 18 comprises the skinned cellular structure of clause 17, the core comprising a fibre reinforced material.

[0067]

[0069] Clause 19 comprises the skinned cellular structure of clause 17, the core including reinforcement between the cells.

[0068]

[0070] Clause 20 includes the skinned cell structure of clause 17, wherein the skin includes at least one of a precured composite material or a prepreg composite material.

[0069]

[0071] From the foregoing, it will be appreciated that exemplary methods, apparatus, and articles of manufacture have been disclosed that enable high strength, lightweight, cost-effective skinned cellular structures. The embodiments disclosed herein can be rapidly manufactured and deployed. As a result, the embodiments disclosed herein can be utilized on a relatively short notice basis (e.g., for emergency field repair or production needs, etc.).

[0070]

[0072] The following claims are hereby incorporated by reference into the Detailed Description, with each claim standing on its own as a separate embodiment of this disclosure.

Claims

1. 1. An apparatus for manufacturing a skinned cell structure, comprising: an attachment device for attaching a plurality of the foam structures together to define a bundle; a restrainer for restraining the bundle; an activator for adding an activator to the plurality of foam structures to expand a portion of the plurality of foam structures into cells of a first size and another portion of the plurality of foam structures into cells of a second size different from the first size to form a cellular structure within the restrainer; a conditioner for arranging the cell structure to define a core; and an assembler for bonding skins to the core to define a skinned cellular structure.

2. An apparatus for manufacturing a skinned cell structure, comprising: A molder for extruding or pultruding the foam structure; an attachment device for attaching the foam structures together to define a bundle; a restrainer for restraining the bundle; an activator for adding an activator to the foamable structure to form a cellular structure within the confinement device; a conditioner for arranging the cell structure to define a core; and an assembler for bonding skins to the core to define a skinned cellular structure.

3. An apparatus for manufacturing a skinned cell structure, comprising: an attachment device for attaching the foam structures including the fiber reinforcement material together to define a bundle; a restrainer for restraining the bundle; an activator for adding an activator to the foamable structure to form a cellular structure within the confinement device; a conditioner for arranging the cell structure to define a core; and an assembler for bonding skins to the core to define a skinned cellular structure.

4. The apparatus of claim 3 , wherein the fiber reinforcement material is positioned adjacent an exterior surface of the foam structure.

5. An apparatus for producing a skinned cell structure, comprising: an attachment device for attaching the foam structures together to define a bundle; a restrainer for restraining the bundle, the restrainer including end stops at longitudinal ends of the bundle; an activator for adding an activator to the foamable structure to form a cellular structure within the constrainer; a conditioner for arranging the cell structure to define a core; and an assembler for bonding skins to the core to define a skinned cellular structure.

6. 6. The apparatus of claim 1, wherein the restrainer comprises an elastic bladder for laterally surrounding the bundle.

7. The device of claim 6 , wherein the bladder has different elasticities in various portions thereof.

8. The apparatus of claim 1 , wherein the activating agent comprises at least one of thermal energy, electrical current, or a chemical agent.

9. The apparatus of claim 1 further comprising a curing device for curing the skinned cell structure.

10. 1. A method for producing a skinned cell structure, comprising the steps of: attaching a plurality of foam structures together to define a bundle; constraining the bundle; adding an activator to the plurality of foamable structures of the bundle to expand a portion of the plurality of foamable structures into cells of a first size and another portion of the plurality of foamable structures into cells of a second size different from the first size to define a cellular structure; arranging the cellular structure to define a core; and and assembling said core with a skin to define a cellular structure surrounded by said skin.

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