Sand casting hybrid tooling pattern plate and method of manufacturing the same via in SITU casting

Abstract

A method of manufacturing a sand casting hybrid tooling pattern plate and including: forming, via additive manufacturing, a first mold portion having a first interface; forming, via additive manufacturing, a second mold portion with a second interface and a mold aperture; positioning a base plate between the first mold portion and the second mold portion such that the first interface is at least partially positioned within or adjacent to a base plate aperture and the second interface is at least partially positioned within or adjacent to the base plate aperture, the second interface positioned adjacent to but spaced apart from the first interface by a gap; and forming a pattern-forming member coupled to the base plate by casting material into the mold aperture such that the casting material fills the gap between the first mold portion and the second mold portion.

Description

Attorney Docket No. 208273-0015-W001SAND CASTING HYBRID TOOLING PATTERN PLATE AND METHOD OF MANUFACTURING THE SAME VIA IN SITU CASTINGCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 701,670, filed on October 1, 2024, the entire contents of which are incorporated herein.FIELD

[0002] Embodiments relate to a sand casting hybrid tooling pattern plate and a method of manufacturing the same.BACKGROUND OF THE DISCLOSURE

[0003] To produce parts in metals via a sand casting method, it is necessary to compress prepared foundry sand with tooling to form suitable mold cavities into which metal may be poured.

[0004] This requires tooling representative of the desired part which is the ‘master’ or ‘pattern’ from which the mold is being made. To produce both sides of a mold at once, this pattern usually takes the form of a plate with the part geometries mounted on both sides. This plate is traditionally either cut from a monolithic block of material, assembled from multiple machined components, or built up out of carved and hand-worked pieces of wood, tooling board, or other suitable materials worked and blended together to produce a suitable pattern against which to compress foundry sand to form molds.

[0005] The production of pattern plates by traditional methods is both time and labor intensive, and in machining approaches requires substantial material removal to achieve desired part forms.

[0006] For multi-part patterns, assembly usually requires extensive use of fasteners to combine the components together, which introduces a number of knock-on effects and concerns which require additional labor and cost to resolve.SUMMARYAttorney Docket No. 208273-0015-W001

[0007] In some aspects, the techniques described herein relate to a method of manufacturing a sand casting hybrid tooling pattern plate, the tooling used to form a mold from foundry sand, the method including: providing a base plate with a base plate aperture; forming, via additive manufacturing, a first mold portion having a first interface; forming, via additive manufacturing, a second mold portion with a second interface and a mold aperture; positioning the base plate between the first mold portion and the second mold portion such that the first interface is at least partially positioned within or adjacent to the base plate aperture and the second interface is at least partially positioned within or adjacent to the base plate aperture, the second interface positioned adjacent to but spaced apart from the first interface by a gap; and forming a patternforming member coupled to the base plate by casting material into the mold aperture such that the casting material fills the gap between the first mold portion and the second mold portion, the pattern-forming member including at least a portion of a pattern.

[0008] In some aspects, the techniques described herein relate to a method of manufacturing a sand casting hybrid tooling pattern plate, the tooling used to form a mold from foundry sand, the method including: providing a base plate with a base plate aperture; forming, via additive manufacturing, a first mold portion having a first interface; forming, via additive manufacturing, a second mold portion with a second interface and a mold aperture; positioning the base plate between the first mold portion and the second mold portion such that the first interface is at least partially positioned within or adjacent to the base plate aperture and the second interface is at least partially positioned within or adjacent to the base plate aperture, the second interface positioned adjacent to but spaced apart from the first interface by a gap; and forming a patternforming member coupled to the base plate by casting material into the mold aperture such that the casting material fills the gap between the first mold portion and the second mold portion and forms a mechanical joint with the base plate, the pattern-forming member including at least a portion of a pattern.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. l is a method for manufacturing a sand casting hybrid tooling pattern plate.

[0010] FIG. 2 is a schematic view of a base plate of the sand casting hybrid tooling pattern plate during the method of FIG. 1.Attorney Docket No. 208273-0015-W001

[0011] FIG. 3 is a plan view of a base plate of the sand casting hybrid tooling pattern plate of FIG. 2.DETAILED DESCRIPTION

[0012] Before any embodiments are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. Other embodiments, than those described below, are capable of being practiced or of being carried out in various ways.

[0013] FIG. 1 illustrates a method 100 of manufacturing a sand casting hybrid tooling pattern plate (e.g., hybrid pattern plate, tooling). The resulting tooling pattern plate 200, once manufactured, is used to form a mold from foundry sand. The method includes, at step 104, providing a base plate 204 with one or more base plate recesses or apertures 208. The method further includes, at step 108, forming, via additive manufacturing, a first mold portion 300a having a first interface 308a. The method further includes, at step 112, forming, via additive manufacturing, a second mold portion 300b with a second interface 308b and a mold aperture 312. The method further includes, at step 116, positioning the base plate 204 between the first mold portion 300a and the second mold portion 300b such that the first interface 308a is at least partially positioned within or adjacent to the base plate aperture 208 and the second interface 308b is at least partially positioned within or adjacent to the base plate aperture 208. The second interface 308b is positioned adjacent to but spaced apart from the first interface 308a by a gap. The method further includes, at step 120, forming a pattern-forming member 350 with the base plate 204 by pouring (e.g., casting) material into the mold aperture 312 such that material fills the gap between the first mold portion 300a and the second mold portion 300b and couples to the base plate 204. The pattern-forming member 350 comprising a portion or entirety of a pattern, depending upon the individual details of any given embodiment. Further with respect to step 120, forming the pattern-forming member 350 is formed in-situ and coupled with the base plate 204 by one of several possible methods depending on pattern architecture. In some embodiments, curable polymers (e.g., chemically curable) may be poured such that the material fills the gap between the first mold portion 300a and the second mold portion 300b and couples to the baseAttorney Docket No. 208273-0015-W001 plate 204. The polymers can include, but are not limited to, a polyurethane, an acrylate, a methacrylate, an epoxy one or two component resin system, and combinations thereof. In other embodiments, molten aluminum or other alloys may be poured into the mold aperture 312 such that the material fills the gap between the first mold portion 300a and the second mold portion 300b and couples to the base plate 204. The mold portions 300a, 300b are temporarily used to create the tooling pattern plate 200. The mold portions 300a, 300b are used to create the tooling pattern plate and then the mold portions 300a, 300b are removed from the tooling pattern plate. The mold portions 300a, 300b may be reused or discarded.

[0014] Further with respect to step 104, the method may further include machining the base plate 204 to include the base plate aperture 208. The term “machining” as used herein is a subtractive manufacturing process in which a material is removed from the base plate 204. The material may be removed using any suitable means and may include a combination of means. The base plate 204 preferably comprises a metal, such as aluminum, magnesium alloys (e.g., Dowmetal), cast iron, or steel, although any suitable metal may be used.

[0015] In other embodiments, with respect to step 104, the base plate 204 may be formed from a non-metallic material (e.g., wood or polymer) using any suitable method. Accordingly, the method 100 may further include forming the base plate 204 from a nonmetallic material. In one example, the base plate 204 may be formed, via any suitable process (such as machining), from wood. In another example, the base plate 204 may be formed via additive manufacturing using a polymer material. Accordingly, the base plate 204 can include a polymer. Any suitable additive manufacturing technique may be used to create the base plate 204. In such case, the base plate 204, formed from polymer, may include the same features discussed above - a base plate aperture 208 having one or more recesses 212 or projections 220. Such features could be integrally formed with the base plate 204 (e.g., via the additive manufacturing process) or via a suitable subtractive manufacturing method, such as a machining. Additionally, the base plate 204 may be formed in any suitable way. For example, the base plate 204 can be made via filament or pellet-fed extrusion deposition, sheet lamination, directed-energy deposition, selective laser sintering, continuous fiber placement, material jetting, casting, injection molding, compression molding, thermoforming, or machined from stock, to name some potential techniques.Attorney Docket No. 208273-0015-W001

[0016] If used, the polymer used for the base plate 204 is not generally limited and can be any polymer that has the requisite mechanical properties to function as a base plate 204 in a sand casting tooling pattern plate. For example, match plates need sufficient flexural and compressive strength to tolerate up to ~ 150psi transient loads, thermal operating range to maintain strength in hot foundry conditions and processing steps up to 150°F, abrasion resistance to foundry sand with a minimum ASTM-D3363 rating of 8H, and stiffness to resist deflection under uneven sand packing. Example polymers which can be used include, but are not limited to, nylons, PEI, PPA, PEEK, PEKK, PC, ASA, ABS, and UHMW.

[0017] The polymer can be used neat or compounded with an additive such as reinforcing spherical, rough, or fibrous additives. Compounded polymers may also be referred to as polymer composites. In embodiments where the polymer is a polymer composite, the polymer can include at least one other material that can improve mechanical properties of the polymer. An example material includes, but is not limited to, a fiber (e.g., a reinforcing fiber). The fiber can be suspended or spread out in a polymer matrix. Example fibers include, but are not limited to, glass, carbon, basalt, aramid, and combinations thereof. In some embodiments, the polymer includes an additive, such as but not limited to, chopped carbon fibers.

[0018] Additionally, step 104 may further include creating, via machining, a projection 220 (FIG. 2) that extends from the wall 216 of the base plate aperture 208. The projection 220 may be a single projection 220 extending about the entire perimeter of the base plate aperture 208 or there may be multiple projections 220 extending from the wall 216. Additionally, the projections 220 may have any suitable size and shape.

[0019] Alternatively, or in combination with producing projections 220 through the thickness of the base plate 204, step 104 may further include creating, via machining, a plurality of recesses 212 in the wall 216 of the base plate aperture 208. The plurality of recesses 212 extending about the perimeter of base plate aperture 208 and may or may not be equidistantly spaced. The number of recesses 212 is merely exemplary. There may be more or fewer recesses 212 in other embodiments. Additionally, the recesses 212 may have any suitable size and shape or may have alternative spacing than that shown in FIG. 3.Attorney Docket No. 208273-0015-W001

[0020] There is a single base plate aperture 208 shown herein, but in other embodiments there may be additional base plate apertures 208, each having one or more recesses 212 or projections 220 in the walls 216 thereof.

[0021] With respect steps 108 and 112, “additive manufacturing” is an industry standard term (ASTM F2792) and encompasses various manufacturing and prototyping techniques known under a variety of names, including freeform fabrication, 3D printing, rapid prototyping / tooling, and the like. Additive manufacturing techniques are capable of fabricating complex components from a wide variety of materials. Generally, a freestanding object can be fabricated from a computer aided design (CAD) model. A particular type of additive manufacturing process uses light to solidify a photopolymer, creating a solid three-dimensional object.

[0022] The first and second mold portions 300a, 300b may be formed via any suitable additive manufacturing technique from any suitable material that is compatible with material and process used to form the pattern-forming member 350. Even further the first and second mold portions 300a, 300b may be formed from another suitable method, such as machining, casting, or another suitable method.

[0023] Further with respect to step 116, positioning the base plate 204 between the first mold portion 300a and the second mold portion 300b may further include positioning the base plate 204 on the first mold portion 300a such that the first interface 308a is at least partially positioned within or adjacent to the base plate aperture 208. In the illustrated embodiment, a portion of the first interface 308a includes a portion that is below the base plate 204, a portion that extends through the base plate aperture 208, and a portion that is coplanar with a bottom surface 204a of the base plate 204. Additionally, positioning the base plate 204 between the first mold portion 300a and the second mold portion 300b may further include positioning the second mold portion 300b on the base plate 204 such that the second interface 308b is at least partially positioned within or adjacent to the plate aperture 208. In the illustrated embodiment, the second interface 308b includes a portion that extends through the base plate aperture 208, a portion that is positioned at a height above a top surface 204b of the base plate 204, and a portion that is coplanar with the top surface 204b of the base plate 204. This mold and interface configurationAttorney Docket No. 208273-0015-W001 is merely exemplary. The mold portions 300a, 300b and the interfaces 308a, 308b thereof may have any suitable configuration.

[0024] Further with respect to step 120, the material used to form the pattern-forming member 350 may be a castable alloy such as A356, a brass / bronze, or other suitable alloy, or a castable polymer which cures in-mold, such as a polyurethane, acrylate, methacrylate or epoxy one or two component resin system. Accordingly, the pattern-forming member 350 can be composed of only one body made from a polymer, or metal, or could be composed of multiple sequential castings which would permit for portions to be made from either or both. Importantly, to improve interactions between the pattern-forming member 350 and the base plate 204, the materials used to form the pattern-forming member 350 should be compatible and be able to adhere with the material used for the base plate 204. This can also improve overall integrity of the provided tooling pattern plate 200. Additionally, the method may further include forming, by the material of the pattern-forming member 350, a joint with a wall 216 of the base plate aperture 208. For example, with respect to FIG. 3, as the material moves through the mold aperture 312 to the gap between the mold portions 300a, 300b, the material moves into the recesses 212, such that when cured, the material of the pattern-forming member 350 will form a mechanical interference joint with the wall 216 of the base plate aperture 208. Alternatively, as shown in FIG. 2, as the material moves through the mold aperture 312 to the gap between the mold portions 300a, 300b, the material surrounds into the project! on(s) 220, such that when cured, the material of the pattern-forming member 350 will form a mechanical interference joint with the wall 216 of the base plate aperture 208 once solidified.

[0025] Additionally or alternatively, the method may further include applying an adhesive or other preparatory treatment to a surface of the wall 216, the recesses 212, and / or the projection(s) 220 prior to the material being poured. Then, after the material is poured and cured, the patternforming member may also be adhesively coupled to the wall of the base plate 204 (e.g., the wall 216 of the base plate aperture 208). Example adhesives include, but are not limited to, acrylate- based adhesives, methacrylate-based adhesives, and epoxide-based adhesives. An example acrylate-based adhesive includes, but is not limited to, 3M DP810.Attorney Docket No. 208273-0015-W001

[0026] Additionally, in some embodiments, the method may further include applying a ceramic coating to the tooling pattern plate 200. The ceramic coating may aid in the durability of the tooling pattern plate 200. In some embodiments, the ceramic coating may be applied to all or a portion of the base plate 204, all or a portion of the pattern-forming member 350, or both. The ceramic coating increases the hardness of the tooling pattern plate 200, particularly the patternforming member 350. Additionally, over time, the ceramic coating can be reapplied to maintain the hardness of the tooling pattern plate 200 with successive use. The ceramic coating may include combinations of multiple different engineering ceramics, refractory resins, pigments, and other functional additives. Suitable example ceramic coatings include formulations from, but are not limited to, some CERAKOTE® oven-cured and air-cured products. In some embodiments, the ceramic coating is comprised of a suitable polymer system such as, but not limited to, a polyurethane, epoxy, acrylate, methyl or phenyl modified silicone, utilized as a matrix material to form a composite coating with engineering ceramics, such as but not limited to, alumina, zirconia, carbides, and nitrides.

[0027] In some embodiments, the method includes applying a second ceramic coating. The second ceramic coating can be applied to at least a portion (e.g., surface) of the ceramic coating. The description of the ceramic coating can also be applied to the second ceramic coating. Embodiments that include the ceramic coating and the second ceramic coating can be used to assess wear of the tooling pattern plate 200. For example, the ceramic coating can include a pigment, and the second ceramic coating can include a pigment that is different from the pigment of the ceramic coating. As the second ceramic coating experiences wear and is removed from the tooling pattern plate 200, the pigment of the ceramic coating will become more visible. The change of color can be used to assess wear of the ceramic coating(s) and inform a user when the tooling pattern plate 200 requires additional application of a ceramic coating.

[0028] Conventional tooling is often made entirely via machining. The time required to create tooling via machining alone is significant because small details of tooling are difficult to capture. Additionally, because the details are difficult to capture, mistakes during machining are common, and the cost to re-machine the tooling is considerable. In contrast, the disclosed method (using additive and subtractive manufacturing) and the resulting tooling 200 is an easier, faster, and more cost effective production of tooling 200. This is because using machining forAttorney Docket No. 208273-0015-W001 only the base plate 204 reduces the complexity of the machining process and using additive manufacturing to produce molds for the pattern-forming members (which include the details of the tooling 200) is faster and easier. Accordingly, the disclosed method and resulting tooling 200 allows for a reduction in raw materials costs, due to reducing required input starting material for machining portions of the assembly and processing time / effort to achieve desired tooling surfaces. Additionally, there is reduced labor and machine-time requirement to produce machined portions of the assembly, due to moving complex features to parts produced by additive manufacturing.

[0029] Clauses

[0030] Clause 1. A method of manufacturing a sand casting hybrid tooling pattern plate, the tooling used to form a mold from foundry sand, the method comprising: providing a base plate with a base plate aperture; forming, via additive manufacturing, a first mold portion having a first interface; forming, via additive manufacturing, a second mold portion with a second interface and a mold aperture; positioning the base plate between the first mold portion and the second mold portion such that the first interface is at least partially positioned within or adjacent to the base plate aperture and the second interface is at least partially positioned within or adjacent to the base plate aperture, the second interface positioned adjacent to but spaced apart from the first interface by a gap; and forming a pattern-forming member coupled to the base plate by casting material into the mold aperture such that material fills the gap between the first mold portion and the second mold portion, the pattern-forming member comprising at least a portion of a pattern.

[0031] Clause 2. The method of clause 1, wherein the base plate aperture includes a wall that has a projection extending therefrom, and wherein forming the pattern-forming member includes forming, by the material, a mechanical joint with the projection.

[0032] Clause 3. The method of clause 2, further comprising applying an adhesive to a surface of the projection of the base plate aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.Attorney Docket No. 208273-0015-W001

[0033] Clause 4. The method of clause 1, wherein the base plate aperture includes a wall that has a plurality of recesses, the plurality of recesses extending about a perimeter of the base plate aperture, and wherein forming the pattern-forming member includes forming, by the material, a joint within each of the recesses.

[0034] Clause 5. The method of clause 4, further comprising applying an adhesive to a surface of each of the recesses of the base plate aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.

[0035] Clause 6. The method of clause 1, further comprising applying an adhesive to a surface of a wall of the base plate aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.

[0036] Clause 7. The method of clause 1, wherein forming, via additive manufacturing, the first mold portion and the second mold portion includes forming, via additive manufacturing, the first mold portion and the second mold portion from a polymer.

[0037] Clause 8. The method of clause 1, wherein the material used to form the patternforming member comprises a polymer, a metal, or a combination thereof.

[0038] Clause 9. The method of clause 8, wherein the material used to form the patternforming member comprises a polymer that is a photopolymer.

[0039] Clause 10. The method of clause 1, wherein the base plate comprises a metal.

[0040] Clause 11. The method of clause 10, wherein the metal comprises aluminum, a magnesium alloy, cast iron, or steel.

[0041] Clause 12. The method of clause 1, further comprising applying a ceramic coating on at least a portion of the base plate, at least a portion of the pattern-forming member, or both.

[0042] Clause 13. The method of clause 12, wherein the ceramic coating is derived from a polymer system selected from the group consisting of a polyurethane, an epoxy, an acrylate, a methyl or phenyl modified silicone, and any of the foregoing further comprising an engineering ceramic.Attorney Docket No. 208273-0015-W001

[0043] Clause 14. The method of clause 1, wherein coupling the pattern-forming member to the base plate includes coupling the pattern member to the base plate without fasteners.

[0044] Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention as described.

[0045] Various features of the invention are set forth in the following claims.

Claims

Attorney Docket No. 208273-0015-W001CLAIMSWhat is claimed is:

1. A method of manufacturing a sand casting hybrid tooling pattern plate, the tooling used to form a mold from foundry sand, the method comprising: providing a base plate with a base plate aperture; forming, via additive manufacturing, a first mold portion having a first interface; forming, via additive manufacturing, a second mold portion with a second interface and a mold aperture; positioning the base plate between the first mold portion and the second mold portion such that the first interface is at least partially positioned within or adjacent to the base plate aperture and the second interface is at least partially positioned within or adjacent to the base plate aperture, the second interface positioned adjacent to but spaced apart from the first interface by a gap; and forming a pattern-forming member coupled to the base plate by casting material into the mold aperture such that the casting material fills the gap between the first mold portion and the second mold portion, the pattern-forming member comprising at least a portion of a pattern.

2. The method of claim 1, wherein the base plate aperture includes a wall that has a projection extending therefrom, and wherein forming the pattern-forming member includes forming, by the material, a mechanical joint with the projection.

3. The method of claim 2, further comprising applying an adhesive to a surface of the projection of the base plate aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.

4. The method of claim 1, wherein the base plate aperture includes a wall that has a plurality of recesses, the plurality of recesses extending about a perimeter of the base plate aperture, and wherein forming the pattern-forming member includes forming, by the material, a joint within each of the plurality of recesses.Attorney Docket No. 208273-0015-W0015. The method of claim 4, further comprising applying an adhesive to a surface of each of the plurality of recesses of the base plate aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.

6. The method of claim 1, further comprising applying an adhesive to a surface of a wall of the base plate aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.

7. The method of claim 1, wherein forming, via additive manufacturing, the first mold portion and the second mold portion includes forming, via additive manufacturing, the first mold portion and the second mold portion from a polymer.

8. The method of claim 1, wherein the material used to form the pattern-forming member comprises a polymer, a metal, or a combination thereof.

9. The method of claim 8, wherein the material used to form the pattern-forming member comprises a polymer that is a photopolymer.

10. The method of claim 1, wherein the base plate comprises a metal.11 . The method of claim 10, wherein the metal comprises aluminum, a magnesium alloy, cast iron, or steel.

12. The method of claim 1, further comprising applying a ceramic coating on at least a portion of the base plate, at least a portion of the pattern-forming member, or both.

13. The method of claim 12, wherein the ceramic coating is derived from a polymer system selected from the group consisting of a polyurethane, an epoxy, an acrylate, a methyl or phenyl modified silicone, and any of the foregoing further comprising an engineering ceramic.

14. The method of claim 1, wherein coupling the pattern-forming member to the base plate includes coupling the pattern-forming member to the base plate without fasteners.Attorney Docket No. 208273-0015-W00115. A method of manufacturing a sand casting hybrid tooling pattern plate, the tooling used to form a mold from foundry sand, the method comprising: providing a base plate with a base plate aperture; forming, via additive manufacturing, a first mold portion having a first interface; forming, via additive manufacturing, a second mold portion with a second interface and a mold aperture; positioning the base plate between the first mold portion and the second mold portion such that the first interface is at least partially positioned within or adjacent to the base plate aperture and the second interface is at least partially positioned within or adjacent to the base plate aperture, the second interface positioned adjacent to but spaced apart from the first interface by a gap; and forming a pattern-forming member coupled to the base plate by casting material into the mold aperture such that the casting material fills the gap between the first mold portion and the second mold portion and forms a mechanical joint with the base plate, the pattern-forming member comprising at least a portion of a pattern.

16. The method of claim 15, wherein the base plate aperture includes a wall that has one of a projection and a recess, and wherein forming the pattern-forming member includes forming, by the material, the mechanical joint with the one of the projection and the recess.

17. The method of claim 16, further comprising applying an adhesive to a surface of the one of the projection or the aperture prior to casting the material, and adhesively coupling the pattern-forming member, once cured, to the base plate.

18. The method of claim 15, wherein the base plate comprises a metal.

19. The method of claim 18, wherein the material used to form the pattern-forming member comprises a polymer, a metal, or a combination thereof.

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