Patent ID: 12251858

DETAILED DESCRIPTION

The following detailed description is merely exemplary in nature and is not intended to limit the application and uses. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding introduction, brief summary or the following detailed description. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent example functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in an embodiment of the present disclosure.

As used herein, the term “axial” refers to a direction that is generally parallel to or coincident with an axis of rotation, axis of symmetry, or centerline of a component or components. For example, in a cylinder or disc with a centerline and generally circular ends or opposing faces, the “axial” direction may refer to the direction that generally extends in parallel to the centerline between the opposite ends or faces. In certain instances, the term “axial” may be utilized with respect to components that are not cylindrical (or otherwise radially symmetric). For example, the “axial” direction for a rectangular housing containing a rotating shaft may be viewed as a direction that is generally parallel to or coincident with the rotational axis of the shaft. Furthermore, the term “radially” as used herein may refer to a direction or a relationship of components with respect to a line extending outward from a shared centerline, axis, or similar reference, for example in a plane of a cylinder or disc that is perpendicular to the centerline or axis. In certain instances, components may be viewed as “radially” aligned even though one or both of the components may not be cylindrical (or otherwise radially symmetric). Furthermore, the terms “axial” and “radial” (and any derivatives) may encompass directional relationships that are other than precisely aligned with (e.g., oblique to) the true axial and radial dimensions, provided the relationship is predominantly in the respective nominal axial or radial direction. As used herein, the term “about” denotes within 10% to account for manufacturing tolerances. In addition, the term “substantially” denotes within 10% to account for manufacturing tolerances.

With reference toFIGS.1and2, a method for composite molding is shown generally as100in accordance with various embodiments. In this example, the method100enables the composite molding of a complex part with reduced post-processing required after molding is complete. The part is composed of a polymer-based material, including, but not limited to a composite material, such as carbon fiber, however, the method and systems described herein are not limited to carbon fiber. Rather, the various teachings of the present disclosure may be applied to any suitable polymer-based composite material. As will be discussed, the method100and the systems described herein result in a mold having a surface finish that requires minimal to no additional processing before use. Further, the method100and systems described herein enable the creation of complex details that are molded onto the part, including, but not limited to letters, numbers, graphics, surface graining, surface textures, trim lines, etc. In addition, the method100and systems described herein enable the formation of locating points, cylindrical shafts for positioning additional components, etc. on the part, which provides for ease of assembly of the part to other components.

In one example, at102, the method100for composite molding begins. At104, with additional reference toFIGS.2-7, the method100includes additively manufacturing a mold shell200,300,400,500,600. The mold shell200,300,400,500,600is composed of a polymer-based material, including, but not limited to stereolithography (SLA) resin.

In this example, the mold shell200,300,400,500,600is additively manufactured using SLA three-dimensional printing. It should be noted that the mold shell200,300,400,500,600may be composed of other polymer-based materials, and additively manufactured using different techniques, including, but not limited to vat polymerization (digital light processing (DLP) three-dimensional printing, etc.), powder bed fusion (selective laser sintering three-dimensional printing, Multi Jet Fusion three-dimensional printing, etc.), fused filament fabrication three-dimensional printing, etc. It should be noted that the use of SLA three-dimensional printing, DLP three-dimensional printing or vat polymerization to form the mold shell200,300,400,500,600typically results in the formation of the mold shell200,300,400,500,600with a smooth surface finish, while the use of the other additive manufacturing techniques may require sanding or smoothing of the surface of the mold shell200,300,400,500,600. The smooth surface finish of the mold shell200,300,400,500,600produced through SLA three-dimensional printing, DLP three-dimensional printing or vat polymerization results in the mold shell200,300,400,500,600being ready to use for composite lay-ups without sanding, which reduces time and processing of the mold shells200,300,400,500,600. Mold shells200,300,400,500,600made via other methods may be sanded smooth before composite lay-up to produce smooth composite parts, however, as discussed, this requires an additional processing step for the mold shells200,300,400,500,600produced via these other methods, which is undesirable. Generally, by additively manufacturing the thin mold shell200,300,400,500,600as described herein, a cost of the mold shell200,300,400,500,600may be reduced, and additionally, complex features, letters, numbers, graphics, etc. may be printed into the mold shell200,300,400,500,600, which reduces post-processing of the manufactured part.

With reference toFIG.2, in this example, the mold shell200includes a first mold half202and a second mold half204that cooperate to form a composite part700(FIG.15). Each of the first mold half202and a second mold half204is integrally formed, monolithic or one-piece. With reference toFIG.3, an exterior view of each of the first mold half202and the second mold half204is shown. Each of the first mold half202and the second mold half204includes a plurality of mold walls206, at least one reinforcement structure208, at least one mold assembly structure210, and at least one part forming cavity212. In addition, although not shown, one or both of the first mold half202and the second mold half204may include a mold identification feature, including, but not limited to text, numbers, symbols, etc. One or both of the first mold half202and the second mold half204may also include instructions for lay-up of the composite material, for example.

Generally, each of the first mold half202and the second mold half204are additively manufactured at an angle, so that each of the first mold half202and the second mold half204are supported during their manufacture. In other embodiments, the first mold half202and/or the second mold half204may include additively manufactured supports to assist in supporting the first mold half202and/or the second mold half204during additive manufacturing. These additively manufactured supports may be removed from the first mold half202and/or the second mold half204upon completion of additive manufacturing via trimming, etc. Each of the first mold half202and the second mold half204has a first or exterior side214and an opposite second or interior side216(FIG.4). Each of the first mold half202and the second mold half204has a first end218opposite a second end220. It should be noted that in this example, the first mold half202and the second mold half204are substantially similar and thus, the same reference numeral will be used to discuss components that are the same and the same reference numeral with an “′” will be used to denote components that are substantially similar. In other examples, the first mold half202and the second mold half204may be different depending upon the composite part to be manufactured.

The plurality of mold walls206define a perimeter of each of the first mold half202and the second mold half204. In one example, each of the first mold half202and the second mold half204has a substantially polygonal perimeter. Each of the mold walls206are planar or straight, and extend from the interior side216for a distance D. As will be discussed, by extending for the distance D, the mold walls206cooperate to retain a strengthening agent228(FIG.12), which provides each of the first mold half202and the second mold half204with temperature and pressure resistance. In one example, the mold walls206include a cavity wall230,230′, a pair of endwalls232and a pair of sidewalls234. The cavity wall230forms the interior side216of the first mold half202and the cavity wall230′ forms the interior side216of the second mold half204. The endwalls232extend along a respective one of the first end218and the second end220, and the sidewalls234interconnect each of the respective endwalls232. With reference toFIG.4, each of the cavity walls230,230′, the endwalls232and the sidewalls234have a thickness T. In one example, the thickness T is about 0.05 millimeters (mm) to about 1.0 millimeters (mm). By providing each of the mold walls206with the reduced thickness T, the mold shell200is thin and easy to produce with a minimal amount of material needed.

In one example, the at least one reinforcement structure208comprises a plurality of ribs236. Generally, each of the ribs236extends between the sidewalls234or extends substantially parallel to the endwalls232. Each of the ribs236has the thickness T (FIG.4). In one example, the ribs236are recessed relative to the sidewalls234such that the ribs236are not flush with the sidewalls234. In other words, the ribs236are defined to extend from the cavity wall230,230′ to proximate a terminal surface of the sidewalls234. This enables the strengthening agent228to encapsulate the ribs236such that the ribs236are internal to the strengthening agent228once the strengthening agent228is coupled to the first mold half202and the second mold half204. The ribs236cooperate with the cavity wall230,230′ to define a plurality of chambers238to receive the strengthening agent228. It should be noted that the use of ribs236is merely exemplary, as the at least one reinforcement structure208may comprise any support structure that cooperates with the strengthening agent228, including, but not limited to ribs, lattice, gyroids, or other semi-dense reinforcement structure. In this example, each of the first mold half202and the second mold half204includes four ribs236, however, the first mold half202and the second mold half204may include any number of ribs236, and may not include the same number of ribs236. In certain instances, the reinforcement structure208enables the first mold half202and the second mold half204to be additively manufactured without additive manufacturing supports.

In one example, the mold assembly structure210includes at least one fastener passage240, at least one fastener bore242(FIG.5) and at least one locating structure244(FIG.5). In this example, the mold assembly structure210of the first mold half202includes four fastener passages240and the mold assembly structure210of the second mold half204includes four fastener passages240′. The four fastener passages240and the four fastener passages240′ are spaced apart about the perimeter of the respective one of the first mold half202and the second mold half204. For example, two of the fastener passages240,240′ are defined proximate or near the first end218and two of the fastener passages240,240′ are defined proximate or near the second end220. Typically, the fastener passages240,240′ are defined so as to be near corners associated with each of the first mold half202and the second mold half204to assist in coupling the first mold half202to the second mold half204. Each of the fastener passages240are configured to receive a mechanical fastener, including, but not limited to a bolt, etc., which cooperates with a nut, etc. disposed at an end of the respective fastener passage240′ to clamp the first mold half202to the second mold half204. In one example, the fastener passages240′ associated with the second mold half204have a substantially circular cross-section, while the fastener passages240associated with the first mold half202have a substantially hexagonal cross-section. The circular cross-section of the fastener passages240′ assists in receiving the mechanical fastener and optionally, a tool associated with the mechanical fastener, while the hexagonal cross-section of the fastener passages240assists in receiving the nut, and optionally a tool associated with the nut, to clamp the first mold half202to the second mold half204. It should be noted that the fastener passages240,240′ may be the same between the first mold half202and the second mold half204, if desired. Each of the fastener passages240,240′ is in communication with a respective fastener bore242.

With reference toFIG.5, the interior side216of each of the first mold half202and the second mold half204is shown. In this example, each of the first mold half202and the second mold half204includes four fastener bores242, with each of the fastener bores242associated with one of the fastener passages240,240′. The fastener bores242are circular, and are defined through the part forming cavity212. The fastener bores242enable the mechanical fastener to pass through the interior side216and engage with the nut to clamp the first mold half202to the second mold half204.

In this example, the mold assembly structure210includes four locating structures244. The locating structures244assist in coupling the first mold half202and the second mold half204together, and may provide error proofing. In one example, each of the locating structures244includes a locating pin246and a pin recess248. The first mold half202includes the pin recesses248, while the second mold half204includes the locating pins246. It should be noted that the first mold half202may include the locating pins246and the second mold half204may include the pin recesses248, or each of the first mold half202and the second mold half204may include a combination of the locating pins246and the pin recesses248, if desired. Moreover, the use of the locating pins246and the pin recesses248is merely an example. The locating pins246are defined to extend outward from the cavity wall230′ of the interior side216, and are defined proximate or at corners of the second mold half204to assist in assembling the second mold half204to the first mold half202. Each of the locating pins246is cylindrical, and is also defined proximate or near a respective one of the fastener bores242to ensure that the second mold half204is properly aligned with and coupled to the first mold half202to assist in clamping the second mold half204to the first mold half202with the mechanical fastener. The pin recesses248are defined to extend inward or are defined into the cavity wall230of the interior side216. The pin recesses248are cylindrical and are defined to receive the respective one of the locating pins246when the second mold half204is properly aligned with and coupled to the first mold half202. In this example, each of the pin recesses248are also defined proximate or at corners of the second mold half204to receive the respective one of the locating pins246to assist in assembling the second mold half204to the first mold half202.

In this example, the at least one part forming cavity212is defined by a portion256,256′ of the cavity wall230,230′. Stated another way, the cavity wall230,230′ is formed with a shape that corresponds to the predetermined exterior shape of the composite part700(FIG.15). As the part forming cavity212may have any shape to form any predetermined part, the following description of the part forming cavity212is merely an example. In this example, the part forming cavity212includes a first conduit cavity250,250′, a second conduit cavity252,252′ and a third conduit cavity254,254′ each of which is defined in the portion256,256′ of the cavity wall230,230′. Generally, each of the first conduit cavity250,250′, the second conduit cavity252,252′ and the third conduit cavity254,254′ is recessed relative to a second portion258,258′ of the cavity wall230,230′. The second portion258,258′ of the cavity wall230,230′ forms a contact surface for the respective one of the first mold half202and the second mold half204against the other of the first mold half202and the second mold half204when the first mold half202is coupled to the second mold half204.

In the example of the first mold half202, the cavity wall230defines the first conduit cavity250, the second conduit cavity252and the third conduit cavity254. The first conduit cavity250is substantially semi-cylindrical, and includes a taper259proximate or near the first end218. The second conduit cavity252and the third conduit cavity254are each substantially semi-cylindrical, and are in communication with the first conduit cavity250. The second conduit cavity252is spaced apart from the third conduit cavity254by a section260of the second portion258of the cavity wall230so that the second conduit cavity252is discrete from the third conduit cavity254. A section262of the second portion258of the cavity wall230defines a boundary of the first conduit cavity250, and a section264defines a boundary between the first conduit cavity250and the second conduit cavity252. A section266defines a boundary between the second conduit cavity252and the third conduit cavity254. Each of the pin recesses248and the fastener bores242are defined in respective ones of the sections262,264,266.

In addition, one or more of the cavities250,252,254may include one or more part surface structures270. In this example, the first conduit cavity250includes two pairs of cut or trim line grooves272. The trim line grooves272provide a corresponding line on the exterior surface of the composite part700(FIG.15), which may be used by an operator as a reference for a cutting or trimming operation. The first conduit cavity250includes one pair of trim line grooves272proximate the first end218, and one pair of trim line grooves272proximate the second end220. The first conduit cavity250also includes a recessed tab274. The recessed tab274creates a projection on the exterior surface of the part (FIG. X), which may be used to couple a conduit or hose to the part. Similarly, each of the second conduit cavity252and the third conduit cavity254includes a pair of the trim line grooves272. The second conduit cavity252and the third conduit cavity254also includes at least one of the recessed tabs274.

In the example of the second mold half204, the cavity wall230′ defines the first conduit cavity250′, the second conduit cavity252′ and the third conduit cavity254′. The first conduit cavity250′ is substantially semi-cylindrical, and includes the taper259proximate or near the first end218. The second conduit cavity252′ and the third conduit cavity254′ are each substantially semi-cylindrical, and are in communication with the first conduit cavity250′. The second conduit cavity252′ is spaced apart from the third conduit cavity254′ by the section260of the second portion258′ of the cavity wall230′ so that the second conduit cavity252′ is discrete from the third conduit cavity254′. A section262′ of the second portion258′ of the cavity wall230′ defines a boundary of the first conduit cavity250′, and a section264′ defines a boundary between the first conduit cavity250′ and the second conduit cavity252′. A section266′ defines a boundary between the second conduit cavity252′ and the third conduit cavity254′. Each of the locating pins246and the fastener bores242are defined in respective ones of the sections262′,264′,266′.

In addition, one or more of the cavities250′,252′,254′ may include one or more part surface structures270. In this example, the first conduit cavity250′ includes two pairs of the trim line grooves272. The first conduit cavity250′ includes one pair of trim line grooves272proximate the first end218, and one pair of trim line grooves272proximate the second end220. The first conduit cavity250′ also includes the recessed tab274. Each of the second conduit cavity252′ and the third conduit cavity254′ includes a pair of the trim line grooves272. The second conduit cavity252′ and the third conduit cavity254′ also includes the recessed tab274.

Thus, generally, the cavity wall230,230′ defines the cavities250,250′,252,252′,254,254′ for the manufacture of the composite part700(FIG.15), and also defines the boundaries (sections260,262,262′,264,264′,266,266′) associated with the composite part700(FIG.15). It should be noted that even though the cavity wall230,230′ includes both the cavities250,250′,252,252′,254,254′ and the boundaries (sections260,262,262′,264,264′,266,266′), the thickness of the entirety of the cavity wall230,230′ is the thickness T (FIG.4). The cavity wall230,230′ has the part forming cavity212on a first side280, and an opposite second side282of the cavity wall230,230′ cooperates with the mold walls206and the ribs236to define the chambers238to receive the strengthening agent228.

It should be noted that the mold shell shown inFIGS.2-5may be configured differently for composite molding. For example, with reference toFIGS.6and7, another exemplary mold shell300is shown for use with the method100. As the mold shell300includes components that are the same or similar to components of the mold shell200discussed with regard toFIGS.2-5, the same reference numerals will be used to denote the same components. In this example, the mold shell300includes a first mold half302and a second mold half304that cooperate to form the composite part700(FIG.15), and each of the first mold half302and the second mold half304includes a conformal system301. Each of the first mold half302and a second mold half304is integrally formed, monolithic or one-piece with the conformal system301. With reference toFIG.6, an exterior view of the first mold half302is shown, and an exterior view of the second mold half304is shown inFIG.7. Each of the first mold half302and the second mold half304includes a plurality of mold walls306, a reinforcement structure308, the mold assembly structure210, and the part forming cavity212. In addition, although not shown, one or both of the first mold half302and the second mold half304may include a mold identification feature, including, but not limited to text, numbers, symbols, etc. One or both of the first mold half302and the second mold half304may also include instructions for lay-up of the composite material, for example.

Generally, each of the first mold half302and the second mold half304are additively manufactured at an angle, so that each of the first mold half302and the second mold half304are supported during their manufacture. In other embodiments, the first mold half302and/or the second mold half304may include additively manufactured supports to assist in supporting the first mold half302and/or the second mold half304during additive manufacturing. These additively manufactured supports may be removed from the first mold half302and/or the second mold half304upon completion of additive manufacturing via trimming, etc. Each of the first mold half302and the second mold half304has a first or exterior side314and the opposite second or interior side216(FIG.4). Each of the first mold half302and the second mold half304has the first end218opposite the second end220. It should be noted that in this example, the first mold half302and the second mold half304are substantially similar and thus, the same reference numeral will be used to discuss components that are the same and the same reference numeral with an “′” will be used to denote components that are substantially similar. In other examples, the first mold half302and the second mold half304may be different depending upon the composite part to be manufactured.

The plurality of mold walls306define a perimeter of each of the first mold half302and the second mold half304. In one example, each of the first mold half302and the second mold half304has a substantially polygonal perimeter. Each of the mold walls306are planar or straight, and extend from the interior side216for the distance D. By extending for the distance D, the mold walls306cooperate to retain the strengthening agent228(FIG.12), which provides each of the first mold half302and the second mold half304with temperature and pressure resistance. In one example, the mold walls306include a cavity wall330,330′, the pair of endwalls232, and the pair of sidewalls234. The cavity wall330forms the interior side216of the first mold half302and the cavity wall330′ forms the interior side216of the second mold half304. Each of the cavity walls330,330′, the endwalls232and the sidewalls234have the thickness T (FIG.4).

In one example, the at least one reinforcement structure308comprises a plurality of ribs336. Generally, each of the ribs336extends between the sidewalls234or extends substantially parallel to the endwalls232. Each of the ribs336has the thickness T (FIG.4). In one example, the ribs336are recessed relative to the sidewalls234such that the ribs236are not flush with the sidewalls234. In other words, the ribs336are defined to extend from the cavity wall330,330′ or the conformal system301to proximate a terminal surface of the sidewalls234. This enables the strengthening agent228to encapsulate the ribs336such that the ribs336are internal to the strengthening agent228once the strengthening agent228is coupled to the first mold half302and the second mold half304. The ribs336cooperate with the conformal system301and the cavity wall330,330′ to define a plurality of chambers338to receive the strengthening agent228. It should be noted that the use of ribs336is merely exemplary, as the at least one reinforcement structure308may comprise any support structure that cooperates with the strengthening agent228, including, but not limited to ribs, lattice, gyroids, or other semi-dense reinforcement structure. In this example, each of the first mold half302and the second mold half304includes four ribs336, however, the first mold half302and the second mold half304may include any number of ribs336, and may not include the same number of ribs336. In certain instances, the reinforcement structure308enables the first mold half302and the second mold half304to be additively manufactured without additive manufacturing supports.

The mold assembly structure210assists in forming the mold shell300. In this example, the mold assembly structure210includes the fastener passages240,240′, the fastener bores242(FIG.5) and the locating structures244(FIG.5). Each of the fastener passages240are configured to receive the mechanical fastener, including, but not limited to a bolt, etc., which cooperates with the nut, etc. disposed at an end of the respective fastener passage240′ to clamp the first mold half302to the second mold half304. Each of the fastener passages240,240′ is in communication with a respective fastener bore242. The mold assembly structure210includes four locating structures244to assist in coupling the first mold half302and the second mold half304together, and may provide error proofing. In one example, each of the locating structures244includes the locating pin246and the pin recess248(FIG.5).

The part forming cavity212is defined by the portion256,256′ (FIG.5) of the cavity wall330,330′. Stated another way, the cavity wall330,330′ is formed with a shape that corresponds to the predetermined exterior shape of the composite part700(FIG.15). As the part forming cavity212is the same between the mold shell200and the mold shell300, the part forming cavity212and the interior side216will not be discussed in detail herein. In this example, the part forming cavity212includes the first conduit cavity250,250′, the second conduit cavity252,252′ and the third conduit cavity254,254′ each of which is defined in the portion256,256′ of the cavity wall330,330′. The second portion258,258′ of the cavity wall330,330′ forms a contact surface for the respective one of the first mold half302and the second mold half304against the other of the first mold half302and the second mold half304when the first mold half302is coupled to the second mold half304.

Generally, the cavity wall330,330′ defines the cavities250,250′,252,252′,254,254′ (FIG.5) for the manufacture of the composite part700(FIG.15), and also defines the boundaries (sections260,262,262′,264,264′,266,266′) associated with the composite part700(FIG.15). It should be noted that even though the cavity wall330,330′ includes both the cavities250,250′,252,252′,254,254′ and the boundaries (sections260,262,262′,264,264′,266,266′), the thickness of the entirety of the cavity wall330,330′ is the thickness T (FIG.4). The cavity wall330,330′ has the part forming cavity212on the first side280,280′ (FIG.5), and an opposite second side382of the cavity wall330,330′ cooperates with the mold walls306, the ribs336and the conformal system301to define the chambers338to receive the strengthening agent228. The conformal system301is defined along the second side382of the cavity wall330,330′.

In this example, the conformal system301is a conformal tubing system, which is defined to extend in a serpentine pattern generally indicated as384along at least a portion of the second side382of the cavity wall330,330′. Generally, the conformal system301extends in the serpentine pattern384along the second side382so as to be opposite the first conduit cavity250,250′. The conformal system301also extends in a first loop386on the second side382opposite the second conduit cavity252,252′ and a second loop388on the second side382opposite the third conduit cavity254,254′. Each of the serpentine pattern384, the first loop386and the second loop388are in fluid communication. In this example, the conformal system301includes an inlet390and an outlet392. Fluid, including, but not limited to heated or cooled air, heated or cooled gas, heated or cooled non-Newtonian fluid, heated or cooled liquid, etc. may enter the conformal system301via the inlet390and flow through the serpentine pattern384, the first loop386and the second loop388to exit via the outlet392. The use of a heated fluid may reduce cure time by heating the part forming cavity212, while the use of a cooled fluid may assist in removing the part from the part forming cavity212.

It should be noted while the conformal system301is described herein as being used for the heated or cooled fluid, the conformal system301may also be used to position one or more sensors adjacent to the cavity wall330,330′ to observe the curing of the composite. For example, a strain gauge or a temperature sensor may be inserted through the conformal system301for observing the part forming cavity212. Moreover, in certain examples, the conformal system301may be in fluid communication with the first side380and may be coupled to a source of a vacuum, to assist in coupling the composite to the mold shell300or a pneumatic supply to assist in ejecting the part from the mold shell300. Further, the conformal system301may be used to position electrical wires for heating the mold shell300. Generally, since the conformal system301is integrally formed with the first mold half302and the second mold half304during additive manufacturing, the position of the conformal system301on each of the first mold half302and the second mold half304may be precisely located.

It should be noted that the mold shells200,300shown inFIGS.2-7are merely example mold shells for producing a duct, and that a variety of other mold shells may be additively manufactured to produce a variety of different parts. Moreover, while the mold shells200,300are illustrated and described herein as including two pieces, the mold shells produced using the method100may have any number of pieces and any predetermined geometry. For example, with reference toFIG.8, a mold shell400is shown for use with the method100. In this example, the mold shell400includes a first mold half402and a second mold half404that cooperate to form a composite part. With reference toFIG.8, an interior view of the first mold half402is shown along with an exterior view of the second mold half404. Although not shown, one or both of the first mold half402and the second mold half404may include a mold identification feature, including, but not limited to text, numbers, symbols, etc. One or both of the first mold half402and the second mold half404may also include instructions for lay-up of the composite material, for example.

The first mold half402includes at least one part forming cavity412. Generally, the first mold half402is additively manufactured at an angle, so that the first mold half402is supported during manufacture. In other embodiments, the first mold half402may include additively manufactured supports to assist in supporting the first mold half402and/or the second mold half404during additive manufacturing. These additively manufactured supports may be removed from the first mold half402upon completion of additive manufacturing via trimming, etc. The first mold half402has a first or exterior side414and an opposite second or interior side416. The first mold half402has a first end418opposite a second end420.

In this example, the part forming cavity412is defined by a portion456of a cavity wall430. Stated another way, the cavity wall430is formed with a shape that corresponds to the predetermined exterior shape of the composite part700(FIG.15). In this example, the part forming cavity412includes a first cavity450and a second cavity452defined within the first cavity450. Generally, each of the first cavity450and the second cavity452is recessed relative to a second portion458of the cavity wall430. The second portion458of the cavity wall430receives the second mold half404in the proper orientation relative to the first mold half402when the first mold half402is coupled to the second mold half404. The second mold half404is substantially a rectangular ring. The second mold half404may be received within the first mold half402to form the mold shell400.

In this example, the first mold half402does not define a reinforcement structure that receives the strengthening agent228. Rather, in this example, with reference toFIG.9, a lattice structure492may be used to reinforce the mold shell400once the composite material is positioned within the cavities450,452. In one example, the lattice structure492may be positioned within the second mold half404, when the second mold half404is coupled to the first mold half402. The lattice structure492may be composed of a polymer-based material, including, but not limited to stereolithography (SLA) resin. In this example, the lattice structure492is additively manufactured using SLA three-dimensional printing. It should be noted that the lattice structure492may be composed of other polymer-based materials, and additively manufactured using different techniques, including, but not limited to vat polymerization (digital light processing three-dimensional printing, etc.), powder bed fusion (selective laser sintering three-dimensional printing, MultiJet fusion three-dimensional printing, etc.), fused filament fabrication three-dimensional printing, etc. The lattice structure492may include a portion with enlarged cell walls494, which cooperate to define one or more chambers496. Each of the chambers496may be configured to receive the strengthening agent228to impart temperature and pressure resistance to the mold shell400via the lattice structure492.

It should be noted that the reinforcement structure208associated with the mold shells200,300shown inFIGS.2-7is merely an example, and that a mold shell may include other reinforcement structures for receiving the strengthening agent228. For example, with reference toFIGS.10and11, a mold shell500is shown for use with the method100. With reference toFIG.10, an exterior view of the mold shell500is shown. The mold shell500may include the part forming cavity412of the mold shell400on an interior side. In this example, the mold shell500includes an internal reinforcement chamber502that is accessed via an access opening504defined through a mold wall506. In this example, the internal reinforcement chamber502includes a lattice508, however, the internal reinforcement chamber502may be open or devoid of the lattice508. The internal reinforcement chamber502, and optionally the lattice508, may be additively manufactured with the manufacture of the mold shell500. The internal reinforcement chamber502may be defined within the mold shell500to extend from a first end510to an opposite second end512. The access opening504is defined through the mold wall506about at a center of the mold wall506. The access opening504enables the strengthening agent228to be received within the internal reinforcement chamber502. In one example, the mold wall506may also include one or more drain openings514, which enable excess strengthening agent228to be removed from the internal reinforcement chamber502.

With reference toFIG.11, once the strengthening agent228is received within the internal reinforcement chamber502or the internal reinforcement chamber502is filled with the strengthening agent, the access opening504and the drain openings514may be sealed with one or more additively manufactured covers520. The covers520are sized to occlude the respective one of the access opening504and the drain openings514to seal the internal reinforcement chamber502.

It should be noted that the mold shell shown inFIGS.2-5may be configured differently for composite molding. For example, with reference toFIGS.12and13, another exemplary mold shell600is shown for use with the method100. As the mold shell600includes components that are the same or similar to components of the mold shell200discussed with regard toFIGS.2-5and the mold shell300discussed with regard toFIGS.6and7, the same reference numerals will be used to denote the same components. In this example, the mold shell600includes a first mold half602and a second mold half604that cooperate to form the composite part700(FIG.15), and each of the first mold half602and the second mold half604includes the conformal system301. Each of the first mold half602and a second mold half604is integrally formed, monolithic or one-piece with the conformal system301. Each of the first mold half602and the second mold half604includes a plurality of mold walls606, a reinforcement structure608, the mold assembly structure210, and the part forming cavity212. In addition, although not shown, one or both of the first mold half602and the second mold half604may include a mold identification feature, including, but not limited to text, numbers, symbols, etc. One or both of the first mold half602and the second mold half604may also include instructions for lay-up of the composite material, for example.

Generally, each of the first mold half602and the second mold half604are additively manufactured at an angle, so that each of the first mold half602and the second mold half604are supported during their manufacture. In other embodiments, the first mold half602and/or the second mold half604may include additively manufactured supports to assist in supporting the first mold half602and/or the second mold half604during additive manufacturing. These additively manufactured supports may be removed from the first mold half602and/or the second mold half604upon completion of additive manufacturing via trimming, etc. Each of the first mold half602and the second mold half604has a first or exterior side614and the opposite second or interior side216(FIG.4). Each of the first mold half302and the second mold half304has the first end218opposite the second end220. It should be noted that in this example, the first mold half602and the second mold half604are substantially similar and thus, the same reference numeral will be used to discuss components that are the same and the same reference numeral with an “′” will be used to denote components that are substantially similar. In other examples, the first mold half602and the second mold half604may be different depending upon the composite part to be manufactured.

The plurality of mold walls606define a perimeter of each of the first mold half602and the second mold half604. In one example, each of the first mold half602and the second mold half604has a substantially polygonal perimeter. Each of the mold walls606are planar or straight, and extend from the interior side216for the distance D. By extending for the distance D, the mold walls606cooperate to retain the strengthening agent228(FIG.14), which provides each of the first mold half602and the second mold half604with temperature and pressure resistance. In one example, the mold walls606include a cavity wall630,630′, the pair of endwalls232, and the pair of sidewalls234. The cavity wall630forms the interior side216of the first mold half602and the cavity wall630′ forms the interior side216of the second mold half604.

With reference toFIG.13, each of the cavity walls630,630′ include at least one first wall section632with the thickness T and at least one second wall section634with a second thickness T2. In this example, the cavity walls630,630′ include three second wall sections634, and each of the three second wall sections634alternate with a respective one of the first wall sections632. It should be noted that this arrangement of the first wall sections632and the second wall sections634is merely an example, as the cavity walls630,630′ may include any number and arrangement of second wall sections634. Moreover, while the cavity walls630,630″ are shown and described as having the same arrangement of the first wall sections632and the second wall sections634, the cavity walls630,630′ may each include a different number and arrangement of the first wall sections632and the second wall sections634. The first wall sections632, the endwalls232and the sidewalls234have the thickness T. The second wall sections634have the thickness T2, which is different and greater than the thickness T. In one example, the second thickness T2 is about 1.05 millimeters (mm) to about 5.0 millimeters (mm), and in some examples, the thickness T2 is about 1.05 millimeters (mm) to about 3.0 millimeters (mm). Generally, the second thickness T2 is different and greater than the thickness T to provide rigidity to predetermined portions of the cavity wall630,630′ that may experience increased stress. For example, the second wall sections634may reinforce the cavity wall630,630′ at predetermined locations where the thermal growth rate between the first mold half602and/or the second mold half604and the composite part700(FIG.15) is different. In other examples, the second wall sections634may reinforce the cavity wall630,630′ at predetermined locations where the composite part700(FIG.15) is removed from the first mold half602and/or the second mold half604to provide increased rigidity during demolding. In addition, the second wall sections634may be defined on the cavity wall630,630′ at predetermined locations to control an amount of heat experienced by the composite part700(FIG.15). For example, the second wall section(s)634may be defined at predetermined locations where it is desirable for the composite part to cool slowly. Thus, the cavity walls630,630″ may each be defined with a varying wall thickness to provide reinforcement to the cavity walls630,630″ and/or to control an amount of heat experienced by the composite part700(FIG.15).

In one example, with reference back toFIG.12, the at least one reinforcement structure608comprises a plurality of ribs636. Generally, each of the ribs636extends between the sidewalls234or extends substantially parallel to the endwalls232. Each of the ribs636has the thickness T (FIG.4). In one example, the ribs636are recessed relative to the sidewalls234such that the ribs636are not flush with the sidewalls234. In other words, the ribs636are defined to extend from the cavity wall630,630′ or the conformal system301to proximate a terminal surface of the sidewalls234. This enables the strengthening agent228to encapsulate the ribs636such that the ribs636are internal to the strengthening agent228once the strengthening agent228is coupled to the first mold half602and the second mold half604. The ribs636cooperate with the conformal system301and the cavity wall630,630′ to define a plurality of chambers638to receive the strengthening agent228. It should be noted that the use of ribs636is merely exemplary, as the at least one reinforcement structure608may comprise any support structure that cooperates with the strengthening agent228, including, but not limited to ribs, lattice, gyroids, or other semi-dense reinforcement structure. In this example, each of the first mold half602and the second mold half604includes four ribs636, however, the first mold half602and the second mold half604may include any number of ribs636, and may not include the same number of ribs636. In certain instances, the reinforcement structure608enables the first mold half602and the second mold half604to be additively manufactured without additive manufacturing supports.

The mold assembly structure210assists in forming the mold shell600. In this example, the mold assembly structure210includes the fastener passages240,240′, the fastener bores242(FIG.5) and the locating structures244(FIG.5). Each of the fastener passages240are configured to receive the mechanical fastener, including, but not limited to a bolt, etc., which cooperates with the nut, etc. disposed at an end of the respective fastener passage240′ to clamp the first mold half602to the second mold half604. Each of the fastener passages240,240′ is in communication with a respective fastener bore242. The mold assembly structure210includes four locating structures244to assist in coupling the first mold half602and the second mold half604together, and may provide error proofing. In one example, each of the locating structures244includes the locating pin246and the pin recess248(FIG.5).

The part forming cavity212is defined by the portion256,256′ (FIG.5) of the cavity wall630,630′. Stated another way, the cavity wall630,630′ is formed with a shape that corresponds to the predetermined exterior shape of the composite part700(FIG.15). As the part forming cavity212is the same between the mold shell200and the mold shell600, the part forming cavity212and the interior side216will not be discussed in detail herein. In this example, the part forming cavity212includes the first conduit cavity250,250′, the second conduit cavity252,252′ and the third conduit cavity254,254′ each of which is defined in the portion256,256′ of the cavity wall630,630′. The second portion258,258′ of the cavity wall630,630′ forms a contact surface for the respective one of the first mold half602and the second mold half604against the other of the first mold half602and the second mold half604when the first mold half602is coupled to the second mold half604.

Generally, the cavity wall630,630′ defines the cavities250,250′,252,252′,254,254′ (FIG.5) for the manufacture of the composite part700(FIG.15), and also defines the boundaries (sections260,262,262′,264,264′,266,266′) associated with the composite part700(FIG.15). The cavity wall630,630′ has the part forming cavity212on the first side280,280′ (FIG.13), and an opposite second side682of the cavity wall630,630′ cooperates with the mold walls606, the ribs636and the conformal system301to define the chambers638to receive the strengthening agent228. The conformal system301is defined along the second side682of the cavity wall630,630′.

In this example, the conformal system301is the conformal tubing system, which is defined to extend in the serpentine pattern generally indicated as384along at least a portion of the second side682of the cavity wall630,630′. Generally, the conformal system301extends in the serpentine pattern384along the second side682so as to be opposite the first conduit cavity250,250′. The conformal system301also extends in the first loop386on the second side382opposite the second conduit cavity252,252′ and the second loop388on the second side382opposite the third conduit cavity254,254′ (FIGS.6and7). Each of the serpentine pattern384, the first loop386and the second loop388are in fluid communication. Fluid, including, but not limited to heated or cooled air, heated or cooled gas, heated or cooled non-Newtonian fluid, heated or cooled liquid, etc. may enter the conformal system301via the inlet390and flow through the serpentine pattern384, the first loop386and the second loop388to exit via the outlet392(FIGS.6and7). The use of a heated fluid may reduce cure time by heating the part forming cavity212, while the use of a cooled fluid may assist in removing the part from the part forming cavity212.

With reference back toFIG.1, from104the method100proceeds to106. At106, the method100includes filling at least a portion of the mold shell200,300,500,600with the strengthening agent228. At106, the method includes filling the lattice structure492with the strengthening agent228. In one example, the method100at106includes filling the chambers238,338,638defined by the ribs236,336,636and the second side282,382,682of the cavity wall230,230′,330,330′,630,630′ with the strengthening agent228. The method100at106also includes filling the chambers496of the lattice structure492with the strengthening agent228, or filling the internal reinforcement chamber502with the strengthening agent228. In one example, the strengthening agent228comprises a pourable hardenable liquid, including, but not limited to an epoxy, a resin, a cast silicone, a urethane, etc. It should be noted that the strengthening agent228may also include additional reinforcing agents that alter thermal conductivity and/or mechanical properties of the mold shell200,300,500,600or lattice structure492, including, but not limited to metal, glass beads, composite fibers, etc.

At108, the method100includes curing or hardening the strengthening agent228to form a mold. Generally, the mold shell200,300,400,500,600with the hardened strengthening agent228provides a system for composite molding. The strengthening agent228may be cured by the passage of a predetermined amount of time, by subjecting the mold shell200,300,500,600or lattice structure492with the strengthening agent228to a predetermined temperature and/or pressure, by subjecting the mold shell200,300,500,600or lattice structure492with the strengthening agent228to light, etc. In the example of the mold shell200,300,600with reference toFIG.14, the mold shell200,300,600is shown with the strengthening agent228cured to form a mold702. It should be noted that the mold702includes the first mold half202,302,602and the second mold half204,304,604each filled with the strengthening agent228, which has been cured or hardened. In this example, the strengthening agent228is a polyurethane, which is not transparent once hardened. In other examples, the strengthening agent228may harden to be transparent or clear, such that instructions regarding the use of the mold shell200,300,500,600or lattice structure492may be printed on or positioned within the chambers238,338,496,502,638and visible once the strengthening agent228is cured. Generally, the strengthening agent228may harden to be transparent or clear, or may harden to a desired color. In the example ofFIG.14, the strengthening agent228is poured into each of the chambers238,338,638so as to extend from the second side282,382,682of the cavity wall230,230′,330,330′,630,630′ to at or proximate the terminal end of the mold walls206,306,606. It should be noted that in the view ofFIG.14, the first mold half202,302,602is shown with the strengthening agent228filling the chambers238,338,638the second mold half204,304,604is filled with the strengthening agent228in the same manner.

Generally, the strengthening agent228when hardened improves the resistance of the mold shell200,300,500,600or lattice structure492to deformation caused by heat, pressure, etc. The use of the strengthening agent228in combination with the additively manufactured mold shell200,300,500,600or lattice structure492enables the mold shell200,300,500,600or lattice structure492to withstand temperatures and pressure during the composite molding, which the mold shell200,300,500,600or lattice structure492without the strengthening agent228may not be able to withstand. Thus, the use of the mold shell200,300,500,600or lattice structure492with the strengthening agent228provides the mold, such as the mold702(FIG.14), that is substantially equivalent in performance to a metal or metal alloy mold, but the use of the mold shell200,300,500,600or lattice structure492results in improved surface finish and enables hard to machine features to be formed in the composite part during molding, which thereby reduces post-processing of the composite part.

With reference back toFIG.1, the method100at110includes laying-up the composite material within the mold shell200,300,400,500,600. In one example, the composite material comprises any suitable polymer-based material, including, but not limited to carbon fiber, etc. In one example, layers of composite material are applied to the mold shell200,300,400,500,600and each layer is wetted with a resin. In one example, the composite material is pre-impregnated (“prepreg”) with resin prior to placement in the mold shell200,300,400,500,600. In addition to composite materials, any product that is manufactured in a mold may have the mold produced via blocks104-108of the method100for molding the product, including, but not limited to, sheet wood bending, injection molding, urethane or silicone castings, vacuum thermoforming, and stamping.

Once the composite material lay-up is completed, at112, the method100includes assembling the mold. In the example of the mold702(FIG.14) formed by the mold shells200,300,600with the strengthening agent228, with the locating structures244aligned, the mechanical fastener is inserted through the fastener passages240′, through the fastener bores242and secured with the nut inserted through the fastener passage240to clamp the first mold half202,302,602to the second mold half204,304,604. In the example of the mold shell400, the second mold half404may be coupled to or positioned into the first mold half402, and the lattice structure492may be coupled to or positioned within the second mold half404.

At114, the method100includes curing the mold, such as the mold702(FIG.14), to form the composite part700. For example, the method100includes positioning the mold702in an autoclave to cure the composite material under a predetermined pressure at a predetermined temperature. Generally, the parameters associated with the curing of the mold including the composite material at114is based on the type of composite material contained within the mold. In the example of a carbon fiber composite material, the mold is cured under a vacuum or autoclave pressure and the temperature is about 80 degrees Celsius (° C.) to about 175 degrees Celsius (° C.). The mold702may be cured by the method100for a predetermined period of time, such as about 1 hour to about 12 hours. A secondary post cure at a higher temperature or for a longer period of time may be performed once the composite part is demolded to achieve improved material properties, if desired.

At116, the method100includes demolding and removing the composite part700(FIG.15) from the mold, such as the mold702(FIG.14). In the example of the mold shells200,300,600the mechanical fastener is uncoupled from the nut and removed through the fastener passages240′ and the fastener bores242to unclamp the first mold half202,302,602and the second mold half204,304,604. In the example of the mold shell400, the lattice structure492may be removed from the second mold half404, and the second mold half404may be removed from the first mold half402. With the mold disassembled, with reference toFIG.15, the composite part700may be removed.FIG.15illustrates the exemplary composite part700formed using the mold shells200,300,600. In this example, the composite part700is composed of carbon fiber, and the composite part700is a duct, such as a cooling duct. The composite part700may be removed from the first mold half202,302,602.

With reference back toFIG.1, the method100at118optionally includes finishing the composite part700(FIG.15). For example, the method100at118may include trimming the composite part700along the trim lines formed by the trim line grooves272. The method100at118may also include any suitable post-processing techniques used on raw composite parts such as applying one or more surface treatments to the composite part700, including, but not limited to, sanding a portion of the composite part700(FIG.15); applying a coating such as a clearcoat, a paint, or a ceramic thermal barrier; wrapping the part in thermal insulation such as gold foil, fiberglass and foil wrap, etc. The method100ends at120.

Thus, the method100enables the formation of a composite part, such as the composite part700(FIG.15) using the mold shell200,300,400,500,600which is additively manufactured and enhanced with the strengthening agent228. The use of the additively manufactured mold shell200,300,400,500,600along with the strengthening agent228enables the mold shell200,300,400,500,600to withstand the temperature and pressure involved in curing the composite part700without deformation of the mold shell200,300,400,500,600. This ensures quality of the composite part700, and in addition, enables the use of higher temperature composite resins, which results in a composite part that can withstand greater temperatures. Stated another way, the use of the additively manufactured mold shell200,300,400,500,600along with the strengthening agent228enables the use of different composite materials, which offer various performance benefits and cure at higher temperatures. In addition, the use of the additively manufactured mold shell200,300,400,500,600enables the formation of hardware bosses (nut and bolt, clamping recesses, etc.), part edge lines for trimming and/or assembly, embossing or engraving lettering or graphics, surface graining and/or surface textures, features to position additional components (such as cylindrical shafts, etc.) on the composite part700during printing of the mold shell200,300,400,500,600, without requiring additional processing steps on the formed composite part. Typically, multiple machine setups and/or hand operations are required to achieve the same level of detail on molds formed using metal, metal alloy or foam.

The use of the additively manufactured mold shell200,300,400,500,600along with the strengthening agent228enable the mold shell200,300,400,500,600to be manufactured with permanent manufacturing instructions, such as fiber lay-up direction, underneath the strengthening agent228, which may be transparent. Generally, molds composed of metal, metal alloy or foam would require machining in text, or using non-permanent marking methods such as paint pens or markers that may require reapplication. Further, the use of the additively manufactured mold shell200,300,400,500,600enables the mold shell200,300,400,500,600to be scaled, if needed, via scaling the digital computer aided design (CAD) data used to print the part to accommodate thermal growth of the composite material. The use of the additively manufactured mold shell200,300,400,500,600also allows complex geometry to be included in the mold shell200,300,400,500,600that may be difficult to achieve with machining. The use of the additively manufactured mold shell600with the variable wall thickness, such as the thickness T and the second thickness T2 of the cavity walls630,630′ accommodates areas of the mold shell600with different stress and thermal profiles. This variable wall thickness would also be substantially impractical to create via machining, for example.

It should be noted that the part forming cavity212,412may be coated with a mold release film. In addition, first mold half202,302,402,602the second mold half204,304,404,604and/or the mold shell500may be coated with paint or a hardener to extend the life of the mold shell200,300,400,500,600. Generally, a surface finish of the mold shell200,300,400,500,600is such that the mold shell200,300,400,500,600does not require sanding or other surface finish enhancements before the lay-up of the composite material. The use of the strengthening agent228also reduces the time required to form the mold shell200,300,400,500,600as the strengthening agent228enables the use of thin walls for the mold shell200,300,400,500,600. In addition, any changes in the design of the composite part may be made by modifying the CAD data associated with the mold shell200,300,400,500,600and does not require reprogramming of a tooling machine, for example. Thus, the method100enables easy part variations without requiring retooling or reprogramming.

It should be noted that one or more sensors may be positioned adjacent to the part forming cavity212of the mold shell200,300,400,500,600without requiring the use of a conformal system, such as the conformal system301. Rather, the one or more sensors may be positioned adjacent to the part forming cavity212and secured during the curing or hardening of the strengthening agent228.

While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the disclosure as set forth in the appended claims and the legal equivalents thereof.