Molding method for making chiral component

Abstract

A method is disclosed that enables the use of a single preform charge jig to produce a preform charge suitable for producing a chiral component and its mirror image. The method utilizes a preform charge having a flat planar form, which differs from a near net shape preform charge used in applicant legacy methods. Two identical examples of a preform charge are manufactured from the preform charge fixture. A first instance of the preform charge is placed in a first orientation in a first compression mold for manufacturing a first part. A second instance of the preform charge is placed in a second orientation in a second compression mold for manufacturing a second part. The second orientation is obtained by rotating the second instance of the flat planar preform charge by 180 degrees relative to the first orientation about an axis parallel to a reflection axis of the first instance and the second instance of the preform charge.

Description

[0001] Statement on the relevant application

[0002] This specification claims priority to U.S. patent application serial number 63 / 349,921, filed on June 7, 2022, and incorporated herein by reference. Technical Field

[0003] The present invention relates to a molded material, specifically a method and an apparatus for molding a fiber-reinforced composite material component, and a fiber-reinforced composite material component manufactured using the method and the apparatus. Background Art

[0004] Composite materials, whose fibers are embedded in a supporting matrix material, are used to make strong yet lightweight components. These composites have an attractive combination of properties and offer significant manufacturing, performance and economic advantages.

[0005] Applicants have disclosed the use of a preform charge as a feed structure for a compression molding process to produce fiber composite parts. The preform charge comprises an arrangement of preforms based on fiber bundles. Each preform consists of a bundle of co-aligned resin-impregnated fibers, typically derived from a tow prepreg or the output of a resin impregnation line. In addition to being cut to the required size, each preform is also typically specially shaped. This provides an arrangement of preforms that matches the contour of the mold cavity in which the preform will be placed and provides the required fiber alignment throughout the mold. This alignment is maintained in the final part and produces a part with superior mechanical properties.

[0006] The preform charge is usually produced in a special fixture. The fixture has a structure suitable for arranging the preforms into a typical three-dimensional form, which is usually very close to the shape / size of the part to be formed ("near net shape"). The fixture may include, for example, a plurality of clamps (for defining the arrangement of the preforms) and clamps to fix the arranged preforms. In some other embodiments, the fixture includes a cavity that determines how the preforms are arranged and clamps for fixing. Because the preforms usually have a circular / elliptical cross-section and are usually stacked (to provide a three-dimensional form), the clamps stabilize / fix the stack and provide a certain degree of minimum downward and forward, and are described below.

[0007] After being properly arranged by the clamp, multiple preforms are "tacked" together. The term "tack" refers to heating to the softening point (but not melting) to effectively connect the preforms. Although the tack produces an integral structure, the individual preforms retain various aspects of their original form. In some cases, a minimum compression, such as supplied by a clamp, is applied to the tack operation. Since the resin in the preform is not heated to liquefaction (the preform is usually heated to a temperature above the heat deformation temperature of the resin but below the melting point), and the applied pressure is usually very low (less than 100 psig and in some cases it is nothing more than "gravity" acting on the preform), the preform charge is not fully consolidated and therefore cannot be used as a finished part. But connected in this way, the preform will not move, thereby maintaining the desired geometry and specific alignment of each preform in the combination. For example, see the published patent application US2020 / 0114596 and U.S. Patent No. 11,090,883, which are incorporated herein by reference.

[0008] While preform charging offers many advantages, its manufacture requires the design, fabrication and use of specific preform charging fixtures. For certain types of finished parts - particularly parts that require two separate molds where the molds are chiral - using preform charging can be problematic.

[0009] Chirality is the property of asymmetry. An object is "chiral" if its mirror image cannot be superimposed. Examples of chiral structures include certain anatomical features, such as the human hand, foot, and ear, among others.

[0010] The following example illustrates the problems caused by chiral components. Suppose a manufacturer must provide a fiber composite insole for a pair of sports shoes. Different insoles are required for the left and right sports shoes. Of course, two different molds are required to produce these two insoles. In a conventional compression molding process, the feed ingredients (usually multiple pieces of fiber and resin) will be placed one by one into each mold, forming a "stack" from which the component is molded. No preform charging is used, and no preform charging fixture is required.

[0011] However, Applicant's process does use preform charges that are produced prior to the forming operation. In the example of a fiber composite insole, two different preform charge fixtures are required; a first fixture to produce the preform charge for the left insole and a second preform charge fixture to produce the preform charge for the right insole. Thus, using preform charges for this component requires the design and manufacture of two preform charge fixtures with the associated expense. Moreover, consider that in the case of footwear, insoles must be produced in as many different sizes as the different sizes of sports shoes are sold in them. If sports shoes are sold in ten different sizes, then twenty preform charge fixtures are required - two for each size.

[0012] It would be beneficial to be able to fabricate such a pair of chiral components using a preform charge as a feed component, but to do so via a preform charge manufacturing process that does not require two preform charge fixtures. Summary of the invention

[0013] Embodiments of the present invention avoid the problems set forth above, thereby improving manufacturing efficiency, reducing design and tooling requirements and, therefore, reducing costs. More specifically, some embodiments of the present invention enable a single preform charge fixture to produce preform charges suitable for producing a chiral component and its mirror image. A non-limiting example of a chiral component made via embodiments of the present invention is a "left" insole (for a left sneaker, shoe, etc.) and its mirror image, a "right" insole (for a right sneaker, shoe, etc.).

[0014] Consider again the manufacture of a fiber composite insole, as discussed in the Background section. A right insole and a left insole are required. The lower surface of a human foot is contoured, and thus the insole must be correspondingly contoured. Applicant's preform charges have heretofore been formed into near net shape structures. Thus, using this prior art approach, the preform charge used to form the insole would be contoured (e.g., arch, etc.) to match the contour of the final part.

[0015] For example, suppose a preform charge fixture is created to produce a preform charge for molding a right insole. Due to the contoured nature of the "right" preform charge, it cannot simply be "flipped" to create a preform charge suitable for molding a left insole. This problem can be visualized by "mentally" flipping one's right foot over their left foot. While the toes of the right foot will overlie the corresponding toes of the left foot (so that the toes are properly positioned for the creation of the left insole via this flipping action), the bottom of the right foot (with its contoured surface) will face upward, rather than downward as desired.

[0016] According to the present teachings, the problem is solved by producing a preform charge from a single preform charge tool, which is used to form both a chiral component and its mirror image component during molding. The key feature of the preform charge is its flat planar form, which is unusual because applicant's preform charges typically have a near net shape. The preform charge having an orientation for molding a right insole is rotated about an axis parallel to the axis of reflection of the left and right insole pair, resulting in a mirror image orientation that enables the preform charge to be used to mold a left insole.

[0017] According to an illustrative embodiment, a method for producing a preform charge suitable for producing a chiral component and its mirror image, wherein the component is contoured, includes:

[0018] Design a pair of parts where the resulting part contains as much continuous fiber as possible across the major dimensions of the part;

[0019] projecting the contoured surface of the first component onto a flat plane, wherein the form projected onto said flat plane becomes the basis for designing an arrangement of preforms for producing a charge of preforms;

[0020] Calculation of the expected gap resulting from pressing a flat preform arrangement onto a contoured surface (e.g. during a forming operation);

[0021] Designing a flat preform arrangement that matches the projection of the contoured surface onto the flat plane, adding compensating preforms as needed to fill gaps created (due to pressing the flat arrangement onto the contoured surface during molding);

[0022] ·Placing the preform arrangement in the preform loading fixture;

[0023] · snapping the preforms together to produce a first (flat planar) charge of preforms; and

[0024] - Repeat the previous two operations to produce a second (flat planar) preform charge.

[0025] To form a chiral component and its mirror image:

[0026] • Placing a first preform charge into a mould for forming a first component and then compression moulding it to form the first component.

[0027] • "Flip" or rotate the second preform charge 180 degrees about an axis parallel to the "reflection axis". In this context, the reflection axis is the axis across which the desired mirror image is produced.

[0028] placing a second preform charge in an inverted / rotated orientation into the mold for forming the second component,

[0029] And then compression molded to form the second component.

[0030] In some embodiments, embodiments of the present invention provide a method for manufacturing a first contoured component and a second contoured component, wherein the first contoured component and the second contoured component are mirror images of each other but exhibit chirality and are not superimposable, the method comprising:

[0031] A first example of manufacturing a flat planar preform charge via a preform charge fixture;

[0032] placing the first instance of the preform charge in a first mold for forming the first contoured component, wherein the first instance of the preform charge has a first orientation in the first mold;

[0033] compression molding the first contoured component;

[0034] manufacturing a second instance of the preform charge via the preform charge fixture, wherein the second instance is identical to the first instance;

[0035] placing the second instance of the preform charge in a second mold for molding the second contoured part, wherein the second instance of the preform charge has a second orientation in the second mold, wherein the second orientation is obtained by rotating the second instance of the preform charge by 180 degrees relative to the first orientation about an axis parallel to the reflection axis of the first and second instances of the preform charge; and

[0036] The second contoured component is compression molded.

[0037] In some embodiments, an embodiment of the present invention provides a method for manufacturing a left insole and a right insole of footwear, wherein the left insole and the right insole are mirror images of each other but exhibit chirality and are not superimposable, the method comprising:

[0038] manufacturing, via a preform charge fixture, a first instance of a flat planar preform charge, the first instance having a shape corresponding to a right foot;

[0039] placing said first instance of said preform charge in a first orientation in a first mold for molding said right insole;

[0040] compression molding said first instance of said preform charge to form said right insole;

[0041] manufacturing, via the preform charge fixture, a second instance of the flat planar preform charge, the second instance having the shape corresponding to the right foot;

[0042] placing said second instance of said preform charge in a second mold for molding said left insole in a second orientation, wherein said second orientation is a mirror image of said first orientation; and

[0043] The second instance of the preform charge is compression molded to form the left insole.

[0044] In some embodiments, an embodiment of the present invention provides a method for manufacturing a left insole and a right insole of footwear, wherein the left insole and the right insole are mirror images of each other but exhibit chirality and are not superimposable, the method comprising:

[0045] manufacturing, via a preform charge fixture, a first instance of a flat planar preform charge, the first instance having a shape corresponding to a left foot;

[0046] placing said first instance of said preform charge in a first orientation in a first mold for molding said left insole;

[0047] compression molding said first instance of said preform charge to form said left insole;

[0048] manufacturing, via the preform charge fixture, a second instance of the flat planar preform charge, the second instance having the shape corresponding to the left foot;

[0049] placing the second instance of the preform charge in a second mold for molding the right insole in a second orientation that is a mirror image of the first orientation; and

[0050] The second instance of the preform charge is compression molded to form the right insole. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 Depicted are methods for molding components that exhibit chirality and mirror images of such components in accordance with the teachings of the present invention.

[0052] Figure 2 Describes a method for completing the Figure 1 A method of performing one of the operations of a method.

[0053] Figure 3A and 3B The pressing of a flat planar preform charge onto a contoured surface is illustrated as occurs when molding a component and its mirror image that exhibits chirality in accordance with the teachings of the present invention.

[0054] Figure 4 Describes a method for completing the Figure 1 The method of operation of the second method.

[0055] Figure 5 Describes a method for completing the Figure 1 The method of the third party in the operation of the method.

[0056] Fig. 6A Depicting a preform charge used to form a component exhibiting chirality.

[0057] Figure 6B Describe the invention according to the teachings of the present invention Fig. 6A The same preform loading as the preform loading of FIG. 1 is shown, and the flipping operation is described.

[0058] Figure 7 Depiction Fig. 6AA preform charge, and a component formed therefrom that exhibits chirality. DETAILED DESCRIPTION

[0059] Definitions. The following terms are defined as used in this description and the appended claims:

[0060] • "Fiber" means a single strand of material. A fiber has a length much greater than its diameter.

[0061] • "Fiber bundle" means a plurality (usually a multiple of one thousand) of co-aligned fibers.

[0062] "Stiffness" in the context of a material means resistance to bending as measured by Young's modulus. "Stiffness" when used in the context of a spring or spring assembly means the resistance to displacement from an unstretched / uncompressed state. "Tow" means a bundle of fibers (i.e., a fiber bundle), and unless otherwise specified, these terms are used herein.

[0063] Used interchangeably. Tows are typically available in thousands of fibers: 1K tow (1000 fibers), 4K tow (4000 fibers), 8K tow, etc.

[0064] "Prepreg" means fibers impregnated with resin.

[0065] • "Tow prepreg" means a bundle of fibers (ie, tow) impregnated with resin.

[0066] "Preform" means a section of a plurality of co-aligned, resin-impregnated fibers, generally of equal length.

[0067] Cut to specific lengths, and in many cases, will be shaped (e.g., bent, twisted, etc.) into a specific form to fit the specific part being formed. Preforms are typically derived from tow prepreg (i.e., tow prepreg is segmented into the required lengths), but may also be derived from another source of multiple co-aligned, unidirectionally aligned fibers (e.g., from a resin infusion process, etc.). The cross-section of the preform is preferably, but not necessarily, substantially circular or elliptical. Applicants' use of the term "preform" expressly excludes any size shaped pieces of:

[0068] The term "modifier based on fiber bundles" or "aligned fibers" may be added before the word "preform" herein to emphasize the nature of Applicant's preform and to distinguish it from prior art preforms, which are usually in the form of strips / tapes, sheets or shapes cut from fiber sheets.

[0069] "Preform charge" means a charge of at least loosely joined together (i.e., stapled) to maintain their position relative to each other.

[0070] The preform charge may contain fibers in a form factor other than the form factor of the fiber bundle, and may contain various inserts (passive or active). The preform charge is not fully consolidated.

[0071] • "Preform stack" means an arrangement of individual preforms formed by placing the preforms one by one into a mould cavity.

[0072] A preform stack is distinguished from a preform charge, wherein in the latter the preforms are at least loosely bonded together and the combination is usually formed outside the mould cavity.

[0073] • "Compatible" when used to refer to two different resin materials means that the two resins will mix and combine with each other.

[0074] "Compression molding" is a molding process that involves applying heat and pressure to feed ingredients.

[0075] It is often placed in a female mold part having a mold cavity. When the desired amount of feed ingredients are placed in the female mold part, a second mold part—the male mold part—is connected to the female mold part to close the mold cavity. The male mold part typically includes features that extend into the female mold part to engage the feed ingredients therein. For the applicant's process, the pressure applied to the feed ingredients is typically in the range of about 1000 psi to about 5000 psi, and the temperature, which varies depending on the resin used, is typically in the range of about 150°C to about 400°C. Once the applied heat raises the temperature of the resin above its melting temperature, the resin is no longer solid and will flow. The resin will then conform to the mold geometry via the applied pressure and thereby consolidate the feed ingredients, producing a nascent part with very small void spaces. The high pressure and temperature are typically maintained for several minutes. After this compression molding scheme is completed,

[0076] The mold is cooled and removed from the pressure source. The finished part is removed from the mold.

[0077] "Consolidation" in the context of the present invention means removing void spaces in a group of fibers / resins (e.g., multiple preforms) as much as possible and to an extent acceptable to the final part. The feed structure loses any unique or individual identity, and any pre-existing boundaries between adjacent preforms disappear. This requires significantly increasing pressure via gas pressurization (or vacuum) or mechanical application of force (e.g., rollers, etc.) and high temperature (softening / melting resin).

[0078] "Partial consolidation" in the context of the present invention means that the void spaces in a fiber / resin set have not been removed to the extent required for the final part. As an approximation, full consolidation requires one to two orders of magnitude more pressure than partial consolidation. As a further very rough generalization, consolidating a fiber composite to about 80% of full consolidation requires only 20% of the pressure required to achieve full consolidation.

[0079] • "Neat" resin or other matrix material means the resin / matrix material contains no reinforcing fibers.

[0080] • "About" or "substantially" means + / - 20% relative to a specified figure or nominal value.

[0081] • Additional definitions may be provided contextually elsewhere in this specification.

[0082] It should be understood that any numerical range recited herein includes all sub-ranges contained therein. For example, the range "1 to 10" is intended to include all sub-ranges between (and including) the stated minimum value of about 1 and the stated maximum value of about 10, i.e., having a minimum value equal to or greater than about 1 and a maximum value equal to or less than about 10. As a non-limiting example, the range of "1 to 10 μm" includes "5 to 8 μm", "1 to 4 μm", "2 to 9 μm", etc.

[0083] Feed Components. The basic feed component used with the methods disclosed herein is a fiber tow-based preform (hereinafter "preform"). The preform is typically "formed" from a tow prepreg, but may also be derived from the output of a resin infusion line. In order to form a preform from the tow prepreg (or the output of a resin infusion line), the tow prepreg is cut into segments of the desired size and is typically also shaped (e.g., bent, etc.). Each preform contains thousands of co-aligned resin-infused fibers, typically in multiples of one thousand (e.g., 1k, 10k, 24k, etc.). The preform may have any suitable cross-sectional shape (e.g., circular, elliptical, trilobal, polygonal, etc.), but is most typically circular or elliptical.

[0084] Individual fibers within a preform may have any diameter, typically but not necessarily in the range of 1 to 100 microns. Individual fibers may have any length specific to the application, where the length results from the cutting operation that produces the associated preform. Individual fibers may include an external coating, such as but not limited to a sizing agent, to facilitate handling, adhesion of a binder, minimize self-adhesion of the fiber, or to impart certain properties (e.g., conductivity, etc.).

[0085] Each individual fiber may be formed from a single material or multiple materials (e.g., from the materials listed below), or may itself be a composite material. For example, an individual fiber may include a core (of a first material) coated with a second material, such as an electrically conductive material, an electrically insulating material, a thermally conductive material, or a thermally insulating material.

[0086] In terms of its composition, each individual fiber may be, for example, but not limited to, carbon, carbon nanotubes, glass, natural fibers, aramids, boron, metals, ceramics, polymers, synthetic fibers, and others. Non-limiting examples of metal fibers include steel, titanium, tungsten, aluminum, gold, silver, alloys of any of the foregoing, and shape memory alloys. "Ceramic" refers to all inorganic and non-metallic materials. Non-limiting examples of ceramic fibers include glass (e.g., S-glass, E-glass, AR-glass, etc.), quartz, metal oxides (e.g., alumina), aluminum silicate, calcium silicate, rock wool, boron nitride, silicon carbide, and combinations of any of the foregoing. Non-limiting examples of suitable synthetic fibers include nylon (polyamide), polyester, polypropylene, meta-aramid, para-aramid, polyphenylene sulfide, and rayon (regenerated cellulose).

[0087] Any resin - thermoplastic or thermoset - that bonds to itself under heat and / or pressure may be used in conjunction with embodiments of the present invention.

[0088] Exemplary thermoplastic resins for use in conjunction with embodiments of the present invention include, but are not limited to, acrylonitrile butadiene styrene (ABS), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), liquid crystal polymer (LCP), polyamide (nylon), polyaryletherketone (PAEK), polybenzimidazole (PBI), polybutylene terephthalate (PBT), polycarbonate (PC) and polycarbonate-ABS (PC-ABS), polyethylene (PE), polyetheretherketone (PEEK), polyetherimide (PEI), polyethersulfone (PES), polyterephthalate (PET), polyethersulfone (PES), polyetheretherketone (PEEK), polyetherimide (PEI), polyethersulfone (PES), polyetheretheretherketone (PEEK ... Polyethylene glycol ester (PET), perfluoroalkoxy copolymer (PFA), polyimide (PI), polymethyl methacrylate (PMMA), polyoxymethylene (polyacetal) (POM), polypropylene (PP), polyphosphoric acid (PPA), polyphenylene ether (PPE), polyphenylene oxide (PPO), polyphenylene sulfide (PPS), polyphenylene sulfone (PPSU), polystyrene (PS), polysulfone (PSU), polytetrafluoroethylene (PTFE), polyurethane (PU), polyvinyl chloride (PVC), styrene acrylonitrile (SAN) and styrene butadiene styrene (SBS). The thermoplastic plastic can be a thermoplastic elastomer, such as polyurethane elastomer, polyether ester block copolymer, styrene block copolymer, polyolefin elastomer, polyether block amide, thermoplastic olefin, elastomeric alloy (TPE and TPV), thermoplastic polyurethane, thermoplastic copolyester, thermoplastic polyamide and thermoplastic silicone vulcanizate.

[0089] Non-limiting examples of suitable thermosetting materials include epoxy adhesives, phenolic resins, epoxy resins, melamine, phenol / formaldehyde, polyesters, polyhexahydrotriazines, polyimides, polyisocyanates, polyureas, silicones, urea / formaldehyde, vinyl esters, phenolics, and polycarbonates. Suitable thermosetting materials can be prepared as partially cured B-stages.

[0090] For use in conjunction with the present invention, the preforms are organized into preform charges having a flat planar form factor.

[0091] Figure 1 Depicted is a method 100 for producing two chiral components (more specifically, a chiral component and its mirror image) having a contoured surface in accordance with the teachings of the present invention.

[0092] According to operation S101, two identical instances of a preform charge from which two components are to be molded are produced. According to an embodiment of the present invention, the preform charge has a flat planar shape and is produced from a single preform charge fixture. Figure 2 To further describe, a preform charge having a specific preform arrangement is designed based on the requirements of the final formed part (e.g., mechanical and aesthetic specifications, external forces to which the part will be subjected when in use, etc.). Once the design of the preform charge is established, a preform charge fixture for producing the preform charge is designed and manufactured.

[0093] According to operation S102, a first component is manufactured from a first (identical) instance of a preform charge. Figure 4 In operation S103, a second component is produced from a second (identical) example of the preform charge. This operation is combined with Figure 5 Described in further detail.

[0094] Figure 2 A method for completing operation S101 is depicted; namely, producing two identical instances of a preform charge from which a chiral component and its mirror image are formed.

[0095] According to operation S201, a chiral component and its mirror image are designed. Typically, the design is based on (1) the overall physical properties required of the component, particularly its size and shape, and (2) the mechanical specifications and expected in-use loads to which the component will be subjected. Consideration (2) provides ideal fiber alignment for the component. Fiber alignment can be determined via the methods described in U.S. Patent No. 10,800,115, U.S. Published Patent Applications 2021 / 0069998 and 2021 / 0279384, all of which are incorporated herein by reference.

[0096] In operation S202, the component is projected onto a flat plane. For example, in the case of an insole, this involves projecting all of the rib-like structures and the perimeter of the insole onto a flat plane. The projected form becomes the basis for the design of the preform charge (i.e., the arrangement of the preforms) and the preform charge fixture. For example, the projection can be done using a CAD program. Any CAD program will have a feature that projects an object onto a flat plane, thereby producing a sketch of the "shadow" of the object. This sketch is then used as the basis for the design of the preform charge and the design of the cavity geometry (or splint layout) of the preform charge fixture used to manufacture the preform charge.

[0097] In operation S203 , a gap that will result from pressing the flat planar preform charge onto the contoured surface (ie, during a compression molding operation) is calculated.

[0098] With respect to the previous two operations, when an arc is projected onto a flat plane, the length of the projected image will be shorter than the length of the arc. (See step S202.) Therefore, when a flat planar stack of preforms (i.e., preform charges) sized based on the projection of the contoured part surface is pressed onto the contoured (mold) surface, the stack will be too short to completely cover the contoured surface, resulting in a "gap." (See step S203.)

[0099] Figure 3A and 3B The gap referenced in operation S203 is described. Figure 3A A simplified mold 310 is depicted, which includes a contoured surface 312, against which a flat planar preform charge 314 is to be pressed to imprint a contour onto a finished part. It should be appreciated that the spline length of the contoured surface 312 is greater than the length of the linear preform charge 314, since the endpoints of both the contoured surface 312 and the preform charge 314 extend the same horizontal distance. Figure 3B Depicted are gaps 316A and 316B that are created when preform charge 314 is pressed against contoured surface 312 (a slight gap between the preform charge and the contoured surface is shown for clarity of illustration). The pressing operation is accomplished by a plunger or appropriately shaped convex feature extending from a convex portion (not depicted) of mold 310. While gaps 316A and 316B are depicted at the left and right contoured surfaces 312, it should be appreciated that gaps may also occur at other locations depending on the nature of the contour.

[0100] According to operation S204, a flat preform arrangement is developed based on the projection of the part obtained in operation S202. The ideal fiber alignment determined in operation S201 is appropriately modified to comply with manufacturing related constraints, see, for example, U.S. Pat. No. 10,800,115. Examples of constraints applicable to preforms include, but are not limited to, maximizing the number of straight (unbent) preforms (faster production), minimizing the number of unique bend radii (reducing process variability), maximizing the length of the preform (longer is stronger), etc.

[0101] To account for gaps that occur when the profile is impressed onto a flat planar preform charge during molding, compensating preforms are added to the preform arrangement (beyond what is required based on the projection of the part). This can be done by lengthening preforms close to the gap, or simply adding preforms to fill the gap. In some cases, short preforms (less than 40 mm) are added to the preform arrangement; the fibers from such preforms will preferentially flow towards the gap with the liquefied resin during molding, as the pressure in such (empty) areas will be lower. The gap can be calculated based on:

[0102] The absolute size of the gap (length, width, height);

[0103] The percentage of adjacent segments;

[0104] ·volume;

[0105] The number of preforms of a predetermined size that must be added to fill the gap;

[0106] • The number, length or volume of short preforms (with "flowable" fibers) placed in adjacent sections.

[0107] In operation S205, a preform charging fixture is manufactured for producing the flat preform arrangement determined in operation S204. In some embodiments, the preform charging fixture includes a plurality of clamping plates / columns positioned to facilitate production of the preform arrangement. That is, placing the preforms against the clamping plates produces the desired preform arrangement. Alternatively, a cavity of appropriate size and shape is created and the preforms are placed in the cavity. Clamps are typically included in both types of fixtures.

[0108] In operation S206, the preform is placed in a preform loading fixture. The clamp stabilizes the preform and applies minimal pressure to it (typically less than 100 psig).

[0109] According to operation S207, the preforms are snapped together. For preforms containing thermoplastic resins, this is achieved by heating the resin to a temperature above its heat deformation temperature but below its melting temperature. The high temperature and applied pressure cause the preforms to adhere to each other. Although the result is a single preform, the preforms retain their individuality and, importantly, their orientation relative to each other. The arrangement of preforms is then cooled, producing a preform charge.

[0110] In operation S208, operations S206 and S207 are repeated to manufacture a second flat planar preform charge that is identical to the first preform charge.

[0111] Back to Figure 1 Operation S102 describes forming a first component exhibiting chirality from a first example of a flat planar preform charge. Figure 4 A method of prefabrication operation S102 is depicted. According to operation S401, a first instance of a flat planar preform charge is placed into a mold for making a first component. The preform charge is placed in the mold in a first orientation. According to operation S402, the first component is made by compression molding the first instance of the preform charge.

[0112] Continue to refer Figure 1 , in operation S103, a second component that is a mirror image of the first component is formed. Figure 5 Depicting a method for performing operation S103. According to operation S501, a second instance of the flat planar preform charge is flipped or rotated 180 degrees relative to the first orientation about an axis parallel to the "reflection axis" of the first part-second part pairing. (See, e.g., Figure 6B . ) According to operation S502, a second instance of the preform charge is placed in the mold in a second orientation. According to operation S503, a second component is manufactured by compression molding the second instance of the preform charge.

[0113] Fig. 6A 620-1 is an example of a flat planar preform charge for manufacturing a fiber composite insole according to an embodiment of the present invention. Preform charge 620-1 consists of an arrangement of preforms 622. In this example, all preforms 622 are linear. The preforms are as long as possible to comply with the use of linear (i.e., no bends) preforms. Fig. 6A In the orientation shown in , preform charge 620-1 is placed into a mold for producing a "right" insole.

[0114] Reference Figure 6B , to produce a left insole, another instance of the same preform charge is needed—preform charge 620-2. In accordance with the teachings of the present invention, preform charge 620-2 is rotated 180 degrees about an axis parallel to the "reflection axis" AA—axis BB. In this context, the reflection axis is the axis that "splits" the mirrored preform charge. As shown, this rotation produces a second orientation of the preform charge; namely, the "left" foot orientation.

[0115] Once this second (in this case left foot) orientation is established, the preform charge is placed into the mold of the left insole. Because the preform charge 620 has a flat planar form, it can be flipped as shown to produce the two orientations required for the right and left foot molds in accordance with the teachings of the present invention.

[0116] It is worth noting that in some embodiments, a modified compression molding process is used to compression mold the preform charge (steps S102 and S103). If the flat planar preform charge is pressed against the contoured surface of the mold (e.g., via a plunger, etc.), the relatively rigid preform may fracture under the applied force. In some embodiments, a male mold component (e.g., a plunger, etc.) is brought into contact with the preform, applying only minimal force thereto. The mold is then heated to an intermediate temperature, e.g., just above the glass transition temperature T of the resin in the preform charge. g As the resin in the preform charge softens, the plunger applies increasing force to the preform charge, causing it to conform to the contoured surface of the mold cavity. The temperature eventually increases to the melting temperature of the resin, T m To achieve a melt flow state, the pressure is raised (ca 1000 to 5000 psi) to consolidate the resin and fibers in the preform charge. After a brief hold (up to a few minutes) at pressure and temperature, the mold is cooled and then depressurized.

[0117] Figure 7 Depicted is a fiber composite insole 730-1 having the outlines as shown produced from the flat planar preform charge 620-1.Due to the flat planar form of the preform charge, only a single preform charge design is required to manufacture the two (chiral) components.

[0118] Region 732 is "out of plane" relative to the major surface of the fiber composite insole 730-1. This region is formed by extending the preform in said region of the preform charge or providing a sufficiently short preform (less than 40 mm) to ensure that fibers from this region will flow to said region during the molding operation.

[0119] It will be understood that this disclosure describes several embodiments and that those skilled in the art may readily devise numerous variations of the invention upon reading this disclosure and that the scope of the invention will be determined by the following claims.

Claims

1. A method for manufacturing a first component and a second component, wherein the first component and the second component are mirror images of each other but exhibit chirality and cannot be superimposed, the method comprising: A first example of manufacturing a flat planar preform charge via a preform charge fixture; placing the first instance of the preform charge in a first mold for forming the first contoured component, wherein the first instance of the preform charge has a first orientation in the first mold; Compression molding the first component; manufacturing a second instance of the preform charge via the preform charge fixture, wherein the second instance is identical to the first instance; placing said second instance of said charge of preforms in a second mould for moulding said second component, wherein said second instance of said charge of preforms has a second orientation in said second mould, wherein said second orientation is obtained by rotating said second instance of said charge of preforms by 180 degrees relative to said first orientation about an axis parallel to an axis of reflection of said first instance and said second instance of said charge of preforms; and The second component is compression molded.

2. The method of claim 1, comprising designing the flat planar preform charge, wherein the flat planar preform charge has a shape based on a planar projection of the first component.

3. The method of claim 1 , wherein designing the flat planar preform charge comprises: arranging a first plurality of fiber tow-based preforms at appropriate areas of the planar projection; calculating a size of a gap in the first mold that would otherwise occur when pressing the flat planar preform charge onto the contoured surface in the first mold; and The first plurality of fiber tow-based preforms are supplemented by extending the length of some of the preforms in the first plurality or adding a second plurality of preforms to the flat planar preform charge to fill the gaps.

4. The method of claim 1 , wherein compression molding the first component comprises pressing the first instance of the preform charge against a contoured surface in the first mold after heating the first instance of the preform charge to at least a heat deformation temperature of a resin in the first instance of the preform charge.

5. The method of claim 1, wherein the first component is an insole for a right article of footwear and the second component is an insole for a left article of footwear.

6. A method for manufacturing a left insole and a right insole for footwear, wherein the left insole and the right insole are mirror images of each other but exhibit chirality and cannot be superimposed, the method comprising: manufacturing, via a preform charge fixture, a first instance of a flat planar preform charge, the first instance having a shape corresponding to a right foot; placing said first instance of said preform charge in a first orientation in a first mold for molding said right insole; compression molding said first instance of said preform charge to form said right insole; manufacturing, via the preform charge fixture, a second instance of the flat planar preform charge, the second instance having the shape corresponding to the right foot; placing said second instance of said preform charge in a second mold for molding said left insole in a second orientation, wherein said second orientation is a mirror image of said first orientation; and The second instance of the preform charge is compression molded to form the left insole.

7. A method for manufacturing a left insole and a right insole for footwear, wherein the left insole and the right insole are mirror images of each other but exhibit chirality and cannot be superimposed, the method comprising: manufacturing, via a preform charge fixture, a first instance of a flat planar preform charge, the first instance having a shape corresponding to a left foot; placing said first instance of said preform charge in a first orientation in a first mold for molding said left insole; compression molding said first instance of said preform charge to form said left insole; manufacturing, via the preform charge fixture, a second instance of the flat planar preform charge, the second instance having the shape corresponding to the left foot; placing the second instance of the preform charge in a second mold for molding the right insole in a second orientation that is a mirror image of the first orientation; and The second instance of the preform charge is compression molded to form the right insole.

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