Fabricated object production method

Abstract

The present invention provides a fabricated object production method that makes it possible to easily remove a support. This fabricated object production method comprises a fabrication step and a removal step. The fabrication step is for fabricating a rough fabricated object (W1) which has a model (M) that is to become a fabricated object and a support (S) that supports a support-requiring part (MO) of the model (M). The removal step is for removing the support (S) from the rough fabricated object (W1) by separating the model (M) and the support (S) after the fabrication step. In the fabrication step, the support-requiring part (MO) is fabricated while forming a prescribed gap (20) between the support (S) and the support-requiring part (MO) of the model (M).

Description

Modeled object manufacturing method

[0001] The present invention relates to a method for manufacturing a three-dimensional object.

[0002] 2. Description of the Related Art In recent years, fused deposition modeling 3D printers have become widely known as object manufacturing devices for manufacturing three-dimensional objects (see, for example, Patent Document 1).

[0003] When using a fused deposition modeling 3D printer to produce a three-dimensional object of a desired shape, depending on the shape of the desired object, supports (support materials) may be required to support the parts of the model that require support (overhanging parts).

[0004] Special Publication No. 2000-500709

[0005] However, since the supports that support the parts of the model that require support during modeling are unnecessary after modeling, it is necessary to separate the two and remove the supports, but this removal is often difficult.

[0006] Therefore, one object of the present invention is to provide a method for manufacturing a molded object that allows supports to be easily removed.

[0007] The method for manufacturing a three-dimensional object according to the present invention is a method for manufacturing a three-dimensional object using a fused deposition modeling 3D printer having a nozzle that ejects a thermally melted modeling material from an ejection port, and comprises: a manufacturing process for manufacturing a rough object having a model that will become the object and a support that supports a support-requiring portion of the model; and a removal process for removing the support from the rough object by separating the model and the support after the manufacturing process. When manufacturing the support-requiring portion of the model that contacts the upper surface of the support in the manufacturing process, a predetermined gap is formed between the ejection port of the nozzle and the upper surface of the support compared to when the modeling material is ejected onto the upper surface of the model that has already been manufactured, and the upper surface of the support is brought into contact with the lower surface of the support-requiring portion of the model due to deformation caused by the weight of the modeling material that hardens after ejection, thereby manufacturing the object.

[0008] In the above-described method for manufacturing a molded object, when the dimension of the predetermined gap in the molding process is H and the opening diameter of the nozzle outlet in a fused deposition model 3D printer is φ, the relationship φ / 2≦H≦φ may be satisfied.

[0009] In the above-described method for manufacturing a shaped object, the support for the rough shaped object in the shaping step may have a cylindrical portion and a plurality of extension portions extending radially from the cylindrical portion.

[0010] In the above-described method for manufacturing a shaped object, the support for the rough shaped object in the shaping step may include an inner cylindrical portion, an outer cylindrical portion, and a connecting portion that connects the inner cylindrical portion and the outer cylindrical portion.

[0011] In the above-described method for manufacturing a molded object, the support for the rough molded object in the molding step may include an additional cylindrical portion located inside the cylindrical portion.

[0012] In the above-described method for manufacturing a shaped object, the cylindrical portion may be formed in the shape of a closed curve.

[0013] In the above-described method for manufacturing a shaped object, the support for the rough shaped object in the shaping step may have a plate-like spiral portion.

[0014] In the above-described method for manufacturing a shaped object, the support for the rough shaped object in the shaping step may have a cylindrical portion.

[0015] In the above-described method for manufacturing a shaped object, the support for the rough shaped object in the shaping step may have a bottom portion and a plurality of cylindrical portions standing on the bottom portion.

[0016] In the above-described method for manufacturing a model, the supports removed in the removing step may be reusable as support members for supporting portions of the model that require support when the same model is manufactured.

[0017] According to embodiments of the present invention, the supports can be easily removed.

[0018] 1A and 1B are diagrams schematically illustrating a fused deposition modeling 3D printer, which is an apparatus for manufacturing a model according to an embodiment of the present invention, where (a) is a front view of the entire printer and (b) is an enlarged view of the modeling head.

[0023] FIG. 1A is a diagram illustrating a model (model) manufactured using the 3D printer, where (a) is a perspective view, (b) is a plan view, and (c) is an A-A cross-sectional view.

[0024] FIG. 1B is a diagram illustrating a method for manufacturing the model, where (a) to (c) are diagrams illustrating a modeling process and (d) is a diagram illustrating a removal process.

[0025] FIG. 1A and 1B are explanatory diagrams illustrating a predetermined gap in the modeling process.

[0026] FIG. 1B is a cross-sectional view of a rough model manufactured in the modeling process.

[0027] FIG. 1B is a partially cutaway plan view of a rough model manufactured in the modeling process.

[0028] FIG. 1B is a partially cutaway perspective view of a rough model manufactured in the modeling process.

[0029] FIG. 1A is a perspective view of a support (a support piece) removed in the removal process, and (b) is a diagram illustrating a modeling process using the support. 1A and 1B are photographs of prototypes of a molded object (satisfying φ / 2≦H≦φ). 1A to 1C are photographs of prototypes of a molded object (satisfying φ / 2≦H≦φ). 1B to 1C are photographs of prototypes of a molded object (satisfying φ / 2≦H≦φ). 1C are diagrams showing another molded object (model) manufactured using the same 3D printer, where (a) is a perspective view, (b) is a plan view, and (c) is an A-A cross-sectional view. 1D are diagrams schematically showing a molded object manufacturing method for manufacturing the same molded object, where (a) to (e) are diagrams of the molding process, and (f) is a diagram of the removal process. 1D are cross-sectional views of a rough molded object manufactured in the same molded object manufacturing process. 1D are partially cut-away perspective views of a rough molded object manufactured in the same molded object manufacturing process. 1D are perspective views of supports (placement pieces that are support members) removed in the removal process. 1D are diagrams showing another example of such supports manufactured in the same molded object manufacturing process, where (a) is a plan view, and (b) is a perspective view. 19A and 19B are diagrams showing yet another example of a model and a support, where (a) is a bottom view of the model, (b) is a perspective view of the model, (c) is a plan view of the support, and (d) is a perspective view of the support. 19B are diagrams showing yet another example of a model and a support, where (a) is a bottom view of the model, (b) is a perspective view of the model, (c) is a plan view of the support, and (d) is a perspective view of the support. 19C are diagrams showing yet another example of a model and a support, where (a) is a bottom view of the model, (b) is a perspective view of the model, (c) is a plan view of the support, and (d) is a perspective view of the support. 19D are explanatory diagrams relating to the support shown in FIG.23 is an enlarged plan view of the support shown in FIG. 23.

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[0098] [009 ... 29A and 29B are diagrams showing still another example of a model and a support, where (a) is a plan view of the model, (b) is a perspective view of the model, (c) is a plan view of the support, and (d) and (e) are perspective views of the support. 29B are enlarged plan views of the support shown in Fig. 29. 29C are diagrams showing a crudely manufactured object made of the model and support shown in Fig. 29, where (a) is a partially cutaway plan view, (b) is a partially cutaway perspective view, (c) is a partially cutaway front view, and (d) is a partially cutaway side view. 29C are diagrams showing still another example of a model and a support, and are schematic cross-sectional views of a crudely manufactured object made of the model and support.

[0019] An embodiment of the present invention will be described with reference to the drawings.

[0020] In Figure 1, reference numeral 1 denotes a fused deposition model 3D printer, which is a model manufacturing device. This fused deposition model 3D printer (hereinafter sometimes simply referred to as "3D printer 1") is a modeling machine that produces a three-dimensional model W by sequentially layering resin, which is a modeling material that has been melted (fused) by heat, one layer at a time based on 3D modeling data.

[0021] The resin used as the modeling material in the 3D printer 1 is, for example, a thermoplastic resin (filament, etc.), and more specifically, for example, PLA, plant fiber-filled PLA, ABS, glass fiber-filled ABS, carbon fiber-filled ABS, PP, glass fiber-filled PP, carbon fiber-filled PP, PC, PC-ABS, ASA, TPE, TPU, cellulose acetate, PA, PETG, etc. Furthermore, the 3D printer 1 is, for example, a single nozzle head model, and only one type of resin is required for modeling; a resin dedicated to support (such as a water-soluble resin) is not required.

[0022] As shown in Figures 1(a) and (b), the 3D printer 1 includes, for example, a box-shaped main body 3 having a modeling chamber 2 inside, a modeling head 4 that is movable within the modeling chamber 2 in the X-axis direction (horizontal, i.e., left-right direction) and the Z-axis direction (up-down, i.e., height direction), and a modeling table 5 that is movable within the modeling chamber 2 in the Y-axis direction (horizontal, i.e., front-to-back direction).

[0023] Since the modeling head 4 can move in the X-axis direction and the Z-axis direction and the modeling table 5 can move in the Y-axis direction, the modeling head 4 moves three-dimensionally relative to the modeling table 5 (as will be described later, the 3D printer 1 is not limited to the configuration shown in Figure 1, and may be configured in any way so long as the modeling head 4 moves at least three-dimensionally relative to the modeling table 5).

[0024] The 3D printer 1 also includes a first drive unit 6 that moves the modeling head 4 in the X-axis direction and the Z-axis direction within the modeling chamber 2, a second drive unit 7 that moves the modeling table 5 in the Y-axis direction within the modeling chamber 2, and a control unit 8 that controls the two drive units 6, 7, etc. based on 3D modeling data such as STL data.

[0025] Then, based on the control by the control unit 8, the modeling head 4 moves three-dimensionally relative to the modeling table 5, and resin (molten resin) is ejected from the nozzle 11 of the modeling head 4 while it is moving.As the ejected resin hardens and solidifies, the resin is layered on the modeling table 5, and a three-dimensional object W of the desired shape is formed.

[0026] However, depending on the shape of the desired object W, as will be described later, a support (support material) S may be required to support the support-requiring portion (overhang portion) MO of the model M that will ultimately become the desired object W. In this case, a rough object W1 consisting of the model M and the support S is formed.

[0027] In other words, when a support S is required, a rough object W1 consisting of a model M and a support S is first formed, and then the support S is removed from the rough object W1 to obtain the desired object W.

[0028] Here, the modeling head 4 of the fused deposition modeling 3D printer 1 with a single nozzle head is, for example, of a molten resin extrusion type, and has a single nozzle 11 that ejects resin melted by heat from a heating means (not shown) within the modeling head 4 from an outlet 10.

[0029] That is, the resin that has been heated and melted by a heating means such as a heater (not shown) is extruded by an extrusion means (not shown) such as a gear inside the model-forming head 4, and is discharged (exhausted) downward from the outlet 10 of one nozzle 11 for discharging the model-forming material. Note that the heating means and the extrusion means may be provided outside the model-forming head 4, rather than inside the model-forming head 4.

[0030] The opening diameter φ of the circular discharge port 10 that opens downward (the opening diameter of the nozzle 11) is, for example, 0.2 mm to 1.0 mm, and in this embodiment is, for example, 0.4 mm (φ=0.4 mm).

[0031] Next, a method for manufacturing a three-dimensional object W shown in FIG. 2 will be described, for example, using the fused deposition modeling 3D printer 1 described above.

[0032] The shaped object W shown in FIG. 2 is, for example, a cap-shaped lid body, and includes a cylindrical portion 16 and a disk-shaped portion 17 integrally provided on the inner circumferential surface of the upper end of the cylindrical portion 16 .

[0033] The disk-shaped portion 17 that constitutes part of the object (model M) W is a support-requiring portion MO that requires support from a support S to prevent it from collapsing under its own weight when being modeled by the 3D printer 1 (during modeling), i.e., a so-called overhanging portion (a portion of the model M that floats in the air) (see Figure 3).

[0034] 3A to 3C are diagrams that schematically show a method for manufacturing a molded object W shown in FIG. 2 (an example of a manufacturing method according to this embodiment), in which (a) to (c) are diagrams of the manufacturing process, and (d) is a diagram of the removal process.

[0035] The first step, the modeling step, is a step of forming (forming) a three-dimensional rough model W1 on the modeling table 5 by ejecting resin (molten resin consisting of one type of modeling material) from the outlet 10 of the nozzle 11 of the modeling head 4, which moves three-dimensionally relative to the modeling table 5, and stacking it on the modeling table 5, as shown in Figures 3(a) to (c).The rough model W1 has a model M that will ultimately become the desired model W, and a support S that supports the support-requiring parts MO of the model M from below during modeling.

[0036] The second step, the removal step, is a step in which the model M and the support S are separated from each other after the modeling step, thereby removing the support S from the rough object W1 to obtain the desired object W, as shown in Figure 3(d).

[0037] In the method for manufacturing a molded object according to this embodiment, in the above-mentioned molding process, the support-requiring portion MO of the model M is molded while temporarily forming (leaving open) a predetermined gap 20 between the support S and the support-requiring portion MO of the model M.

[0038] More specifically, as shown in Figure 4(a), during the modeling process, a predetermined gap (constant gap) 20 in the vertical direction is temporarily formed between the upper surface 21 of the already formed support S and the lower surface 22 of the support-requiring portion MO of the model M being modeled (the lower surface of the linear molten resin immediately after being ejected from the outlet 10 of the nozzle 11 while it is moving horizontally), and a layer on the lower surface of the support-requiring portion MO (one layer that will become the lower surface of the support-requiring portion MO, which is the disk-shaped portion 17) is modeled.

[0039] Furthermore, the method for manufacturing a molded object according to this embodiment satisfies φ / 2≦H≦φ, where H is the dimension (gap height dimension) of the predetermined gap 20 in the molding process and φ is the opening diameter (nozzle diameter) of the nozzle 11 in the fused deposition modeling 3D printer 1.

[0040] Therefore, when φ is 0.4 mm as in this embodiment, for example, H is a dimension within the range of 0.2 mm to 0.4 mm. In other words, the dimension H of the predetermined gap 20 in the modeling process is a dimension within the range of half or more of the opening diameter φ of the nozzle 11 that discharges the modeling material (dissolved resin) and equal to or less than the opening diameter φ.

[0041] Here, the gap 20 temporarily formed in the molding process is almost entirely filled by the resin sagging as the resin deforms (sags) downward due to its own weight, as shown in Figures 4(b) and 5. Note that Figure 3 is a diagram in which the resin sagging is omitted (the same applies to Figure 12).

[0042] In other words, if the molten resin ejected from the outlet 10 of the nozzle 11 moving horizontally cools and hardens at the same time as it is ejected, no dripping will occur. However, since it takes some time for the ejected molten resin to be cooled by the air in the molding chamber 2 and harden, dripping will basically occur due to its own weight, as shown in Figure 4(b).

[0043] As a result, the resin coming out of the outlet 10 of the nozzle 11 moving horizontally sags due to its own weight by the gap 20, and its lower surface 22 comes into contact with the upper surface 21 of the support S (the upper surface of the hardened layer, which is the hardened portion), and is supported by said upper surface 21.

[0044] However, even when the contact portion of the resin supported by the upper surface 21 (the lower surface of the resin drip) hardens and solidifies, it does not firmly integrate (adhere) with the upper surface 21 of the support S, which makes it easy to remove the support S in the removal process after the molding process.

[0045] In other words, in this manufacturing process, the support S, which is not firmly integrated with the model M when the manufacturing is completed and is easily removable, is manufactured together with the model M using the same material.

[0046] Furthermore, it is preferable that the dimension H of the predetermined gap 20, which is required to prevent the model M and the support S from being firmly integrated (adhered), satisfies the relationship φ / 2≦H≦φ, as described above, in relation to the opening diameter φ of the nozzle 11. This is because, for example, if H is smaller than φ / 2, the model M and the support S will be relatively firmly integrated, whereas, for example, if H is larger than φ, the support S will be meaningless and at least a portion of the support-requiring portion MO of the model M will collapse.

[0047] In short, when the relationship φ / 2≦H≦φ is satisfied, collapse of the model M can be prevented, resin dripping can be minimized, and the model M and the support S will not be firmly integrated (adhered).

[0048] 3( d ), for example, an operator can easily separate the model M from the support S on the modeling table 5 (the support S that is additively manufactured in direct contact with the upper surface of the modeling table 5) by simply lifting the model M upward by hand on the modeling table 5 without using any tools (tool-less). In other words, the support S can be extremely easily removed from the model M with just the single action of lifting the model M, and the support S can be easily removed from the rough model W1.

[0049] In addition to the gap 20 described above, as shown in Figures 4 and 5, during the molding process, a predetermined horizontal gap (constant gap) 25 is formed around the entire circumference between the outer surface 26 of the support S (the outer surface of the outer cylindrical portion 32) and the inner surface 27 of the model M (the inner surface of the cylindrical portion 16).

[0050] The dimension D of this gap 25 is, for example, 0.4 mm, which is the same as the opening diameter φ of the nozzle 11. However, it is not necessary for D to be equal to φ, and the dimension D of the gap 25 may be, for example, 0.5 mm.

[0051] 6 and 7 , the support S of the rough object W1 formed in the forming process has an inner cylindrical portion 31 that is annular in plan view, i.e., a cylindrical portion that is, for example, annular in plan view, an outer cylindrical portion 32 that is annular in plan view and has a circular shape in plan view, the outer cylindrical portion 32 being located outward from the inner cylindrical portion 31 at a predetermined distance and in close proximity to the inner circumferential surface 27 of the model M, and has a shape that corresponds to the inner circumferential surface 27 of the model M, i.e., for example, having a circular shape in plan view and centered around the center point P of the inner cylindrical portion 31, and connecting portions (connecting plate-like portions) 33 that are multiple plate-like extensions that are located radially from the center point P of the inner cylindrical portion 31 and extend radially outward from the inner cylindrical portion 31, and that integrally connect the inner cylindrical portion 31 and the outer cylindrical portion 32.

[0052] Furthermore, the support S has a plurality of, for example, two small-diameter cylindrical portions 36, 37 that are additional cylindrical portions that are formed with a smaller diameter than the inner cylindrical portion 31 and are annular in plan view located inside the inner cylindrical portion 31, i.e., annular in plan view centered on the center point P of the inner cylindrical portion 31. In other words, the planar shape (support pattern) of the support S is not restricted to being drawn in one stroke, and the central small-diameter cylindrical portions 36, 37 are not connected to the inner cylindrical portion 31.

[0053] These small-diameter cylindrical portions 36, 37, inner cylindrical portion 31, and outer cylindrical portion 32 are concentric and all have a cylindrical shape (a cylindrical shape with an axial direction in the vertical direction and openings on the top and bottom) centered on a central axis L that extends in the vertical direction (Z-axis direction) and passes through the same center point P (see Figure 5).

[0054] Furthermore, each of the short, cylindrical tubular sections 31, 32, 36, and 37, which are open on the top and bottom, forms a single closed curve in a planar view (the same applies to the tubular sections described below). A single closed curve (Jordan closed curve) is a closed curve that does not intersect with itself. More specifically, it is a curve whose starting point and end point coincide and does not touch or intersect with itself from the starting point to the end point. Single closed curves include circles and ellipses. Furthermore, single closed curves include polygons such as triangles and quadrilaterals, as well as cardioids (heart shapes). Furthermore, a closed curve is a curve whose starting point and end point coincide (for example, a lemniscate), but a lemniscate is not a single closed curve because its area is divided into three parts.

[0055] As shown in FIG. 6 , the angle θ between two adjacent connecting portions (extension portions) 33 in the circumferential direction is, for example, 10°. Although the angles θ are all equal in the illustrated example, they do not necessarily have to be equal. The thickness (plate thickness dimension) t of the plate-shaped connecting portion 33 is the same as the opening diameter φ of the nozzle 11, for example, 0.4 mm. The spacing dimension between the two small diameter cylindrical portions 36, 37 is the same as the spacing dimension between the small diameter cylindrical portion 36 and the inner cylindrical portion 31, for example, 0.8 mm. In the illustrated example, the number of small diameter cylindrical portions 36, 37 located inside (on the inner circumferential side of) the inner cylindrical portion 31 is two, but it may be one or three or more.

[0056] The support S removed in the removal process has exactly the same shape as before removal, as shown in Figure 8 (a), and has an inner cylindrical portion 31, an outer cylindrical portion 32, a connecting portion 33, and small-diameter cylindrical portions 36, 37.

[0057] Therefore, after removal, the support S can be reused as a support piece (support member) that supports the support-requiring part MO of the model M during modeling when manufacturing a model W (a three-dimensional model of the same shape) that is the same as the model W when the support S is modeled together with the model M.

[0058] 2 is repeatedly manufactured (printed) by reusing the removed support S shown in Fig. 8(a) as a placed piece, the printing operation can be stopped temporarily just before the support-requiring portion MO of the model M is printed, and the support S as a placed piece (a base that supports the support-requiring portion MO) can be placed on the printing table 5, as shown in Fig. 8(b), and the printing operation can be resumed to print the support-requiring portion MO of the model M on the placed piece. In Fig. 8(b), (1) is a diagram just before the support-requiring portion MO of the model M is printed, (2) is a diagram showing the placed piece set on the printing table 5, and (3) is a diagram showing the completed printing of the model M.

[0059] In this support reuse modeling process, in which support S is reused as a placing piece in this way and support modeling is not performed, but only the model M is modeled, as in the above-mentioned modeling process, a predetermined gap 20 is temporarily formed between the removed support (placement piece) S and the support-requiring part MO of the model M, and the support-requiring part MO is modeled.

[0060] As a result, the model M and the support (placement piece) S are not firmly integrated (adhered) together, and therefore, even when the support S is to be reused as a placement piece, the model M and the support (placement piece) S can be easily separated in the removal process. Furthermore, the support S after removal can be reused any number of times.

[0061] The method for manufacturing a molded object according to the present embodiment described above includes a manufacturing step of manufacturing a rough object W1 having a model M that will become the object W and supports S that support the support-requiring portions MO of the model M, and a removal step of removing the supports S from the rough object W1 by separating the model M from the supports S after the manufacturing step. When manufacturing the support-requiring portions MO of the model M that contact the upper surfaces 21 of the supports S in the manufacturing step, the distance between the discharge opening 10 of the nozzle 11 and the upper surfaces 21 of the supports S is increased by a predetermined gap 20 compared to when the resin, which is the molding material, is discharged onto the upper surface of the already-manufactured model M. The resin, which is the molding material, hardens after dispensing and deforms due to its own weight, bringing the upper surface 21 of the supports S into contact with the lower surfaces 22 of the support-requiring portions MO of the model M, thereby facilitating separation of the model M from the supports (support structures) S in the removal step. This facilitates removal of the supports S from the rough object W1, thereby improving the manufacturability of the object W.

[0062] Furthermore, support marks are less likely to remain in the support-requiring portions MO of the shaped object (model M) W, and the quality of the shaped object W can also be improved.

[0063] Furthermore, if the dimension of the specified gap 20 in the modeling process is H and the opening diameter of the nozzle 11 in the fused deposition modeling 3D printer 1 is φ, then by satisfying φ / 2≦H≦φ, not only can the collapse of the model M in the modeling process be appropriately prevented, but the separation of the model M and the support S in the removal process can be easily performed, and the support S can be easily and appropriately removed from the rough model W1.

[0064] Furthermore, the support S of the rough object W1 in the manufacturing process has a cylindrical inner tubular portion 31 that is annular in plan view, a cylindrical outer tubular portion 32 that is annular in plan view and is located outside the inner tubular portion 31 and has a shape that corresponds to the cylindrical inner surface of the model M, and a plurality of flat connecting portions (extension portions) 33 that extend radially outward from the inner tubular portion 31 and have a planar line of sight that connect the inner tubular portion 31 and the outer tubular portion 32.This makes it even easier to separate the model M and the support S in the removal process, and makes it even easier to remove the support S from the rough object W1.

[0065] Furthermore, in recent years, modeling software has evolved, and it is sometimes possible to select support structures that are relatively easy to remove. However, because they are easy to remove, problems arise such as the support easily collapsing during modeling. However, in the manufacturing method of this embodiment, such problems do not arise by using a support S of a predetermined shape.

[0066] Furthermore, the manufacturing method of this embodiment makes it possible to obtain supports S that can be easily removed in the removal step, without being limited by modeling software, modeling machines, etc. That is, for example, support generation does not depend on modeling software, and a desired support shape (support material) corresponding to the model shape (model material) can be modeled and embedded in the 3D modeling data, making it possible to apply the method to any fused deposition modeling machine.

[0067] In addition, since the model M and the support S can be made of the same molding material, there is no limit to the number of nozzles, and there is no problem with a single-head 3D printer 1.

[0068] Here, Figures 9(a) and (b) are photographs of prototypes of the object W (satisfying φ / 2≦H≦φ), and Figures 10(a) to (c) are photographs of prototypes of the object W (satisfying φ / 2≦H≦φ).

[0069] The lid of the model M W has a diameter of 53 mm, a height of 10 mm, and a thickness of 1.5 mm. The nozzle diameter φ of the 3D printer 1 is 0.4 mm.

[0070] The prototype shown in Figure 9(a) has dimensions H = 0.2 mm and D = 0.4 mm. In this case, there was almost no resistance, and the model M could be easily separated from the support S on the modeling table 5 simply by lifting the model M by hand above the modeling table 5. Furthermore, although some support marks were visible in the areas MO of the model M that required support, they were not uneven, and there was no problem with the quality of the model W, nor was there any stacking abnormality (collapse). Furthermore, the separated support S can be reused as a placeholder.

[0071] The prototype shown in Figure 9(b) has dimensions H = 0.4 mm and D = 0.4 mm. In this case, there was absolutely no resistance, and the model M could be easily separated from the support S on the modeling table 5 simply by lifting the model M by hand. Although there were some signs of resin dripping in the support-requiring areas MO of the model M, this did not pose a problem for the quality of the model W, and there were no stacking abnormalities (collapses). Furthermore, the separated support S can be reused as a placeholder.

[0072] 10(a) shows a prototype with H = 0.1 mm and D = 0.4 mm. In this case, the model M could not be separated simply by lifting it by hand. After removing the rough molded object W1 from the molding table 5, the model M and the support S were separated using a pair of needle-nose pliers, but some resistance was encountered during the process. Furthermore, there were traces of deformation on the support S caused by pinching it with the needle-nose pliers, meaning that this support S could not be reused as a piece.

[0073] 10(b) shows a prototype with H = 0.5 mm and D = 0.4 mm. In this case, there was absolutely no resistance and the model M could be easily separated from the support S on the modeling table 5 simply by lifting the model M by hand. However, partial stacking abnormalities (collapse) occurred in the support-requiring portion MO of the model M.

[0074] Furthermore, the prototype shown in FIG. 10(c) is a case where there is no support, and in this case, stacking abnormalities (collapse) occurred in the part MO of the model M that required support.

[0075] Therefore, it was confirmed from these prototypes that it is preferable to satisfy φ / 2≦H≦φ.

[0076] In the above embodiment, the case of manufacturing the object W shown in Figure 2 was described, but this is not limited to this. For example, the object W shown in Figure 11 can also be manufactured in a similar manner, and in this case, similar effects can be achieved, such as the support S being easily removed.

[0077] That is, the object W shown in Figure 11 is, for example, a lid body in the shape of a stepped, oblique cap, and comprises a lower cylindrical portion 41, an upper cylindrical portion 42 which is integrally formed on the inner surface of the upper end of the lower cylindrical portion 41 and has a smaller diameter than the lower cylindrical portion 41, and an inclined disk-shaped portion 43 which is integrally formed on the inner surface of the upper end of the upper cylindrical portion 42.

[0078] The upper cylindrical portion 42 and the disk-shaped portion 43 that constitute part of the object (model M) W are support-requiring portions (overhanging portions) MO that require support S to prevent them from collapsing under their own weight when being modeled (during modeling) by the 3D printer 1 (see Figure 12).

[0079] Also, Figure 12 is a diagram that schematically shows a method for manufacturing a molded object (an example of a manufacturing method according to this embodiment) for manufacturing the molded object W shown in Figure 11, where (a) to (e) are diagrams of the manufacturing process and (f) is a diagram of the removal process.

[0080] 2 described above, in the modeling process shown in Fig. 12, the support-requiring portion MO of the model M is modeled while temporarily forming a predetermined gap 20 between the support S and the support-requiring portion MO of the model M so that φ / 2≦H≦φ is satisfied. Note that the predetermined gap 20 is almost entirely filled by resin dripping due to its own weight (see Fig. 13).

[0081] 12 also has an inner cylindrical portion 31, an outer cylindrical portion 32, a connecting portion 33, and small-diameter cylindrical portions 36, 37, as shown in Figures 13 to 15, similar to the case of producing the above-mentioned object W shown in Figure 2. The outer cylindrical portion 32, which has a shape corresponding to the inner circumferential surface 27 of the model M, is composed of a cylindrical lower cylindrical portion 32a corresponding to the lower cylindrical portion 41, and a cylindrical upper cylindrical portion 32b corresponding to the upper cylindrical portion 42.

[0082] Furthermore, the support (placement piece) S after removal shown in FIG. 15 can be reused as a placement piece to support the support-requiring portion MO of the model M when manufacturing the same object W, similar to the support S shown in FIG. 8 .

[0083] The support S according to this embodiment is not limited to those shown in Figures 8 and 15, but may also have a plate-shaped spiral portion (spiral plate portion) 51 that is spiral in plan view (for example, an Archimedes spiral, etc.), as shown in Figure 16, for example.

[0084] 16 is made up of only one continuous plate-like spiral portion 51, and has a cross-sectional shape that can be drawn in one stroke. In other words, this support S is formed by seamless nozzle operation (continuous movement of the nozzle 11) that traces a curve (the same applies to the spiral portion, etc., described below). The thickness (plate thickness dimension) of the spiral portion 51 is the same as the opening diameter φ of the nozzle 11, e.g., 0.4 mm.

[0085] Furthermore, such a spiral (whirlpool) support (support pattern) S can be designed by applying, for example, Archimedes' spiral, and the continuous function that is the basis of the design is expressed in parametric terms as follows:

[0086] X ｔ =t・cos(t) Y ｔ = t sin(t)

[0087] 16, a cap-shaped object W as shown in FIG. 2 can be manufactured in a similar manner, and in this case too, the support S can be easily removed, and similar effects can be achieved.

[0088] In addition, since such a spiral support pattern is created using a continuous function, support design can be completed in a short time, and the operation of the nozzle 11 during modeling becomes smoother, thereby shortening the modeling time.

[0089] The model (a shaped object that is the target of a product or the like) M and the support (a reusable support piece) S produced by the manufacturing method of this embodiment are not limited to the shapes described above, and various shapes are possible, such as those shown in Figures 17 to 32, and in either case, similar effects can be achieved, such as the ability to easily remove the support S.

[0090] 17(a) and 17(b) is, for example, an elliptical lid body, and includes an elliptical cylindrical portion 61 and an elliptical disk portion 62 integrally formed on the inner circumferential surface of the upper end of the cylindrical portion 61. The continuous function that forms the basis for designing the support S when forming such an elliptical model M is expressed as follows in parametric notation, where a≠b.

[0091] X ｔ =at・cos(t) Y ｔ =bt・sin(t)

[0092] The disk-shaped portion (upper plate portion) 62 that constitutes part of the model M is a support-requiring portion MO that requires support by supports S shown in Figures 17(c) and (d) so that it does not collapse under its own weight when being modeled by the 3D printer 1 (during modeling).

[0093] The support S shown in Figures 17(c) and (d) is composed of a plate-shaped spiral portion 63 having an elliptical shape, unlike the support S consisting of a plate-shaped spiral portion 51 having a perfect circular shape shown in Figure 16 above.

[0094] Next, model M shown in Figures 18(a) and (b) is a lid body having, for example, a six-pointed star shape (it can also be a five-pointed star shape or an eight-pointed star shape), and is equipped with a six-pointed star-shaped cylindrical portion 66 and a six-pointed star-shaped plate portion 67 integrally formed on the inner surface of the upper end of this cylindrical portion 66.

[0095] The plate-like portion (upper plate portion) 67 that constitutes part of this model M is a support-requiring portion MO that requires support by supports S shown in Figures 18(c) and (d) so that it does not collapse under its own weight when being modeled by the 3D printer 1 (during modeling).

[0096] The support S shown in Figures 18(c) and (d) has a plate-like spiral portion 68 having a perfect circular shape, and a six-pointed star-shaped outer plate portion 69 integrally formed on the outer periphery of this spiral portion 68, and triangular through holes 70 are formed in this outer plate portion, penetrating through the top and bottom surfaces.

[0097] Next, model M shown in Figures 19(a) and (b) is a lid body that is a structure that utilizes, for example, a three-dimensional Archimedes spiral shape, and includes a cylindrical portion 71 and a hole forming portion 73 that is integrally formed on the inner periphery of this cylindrical portion 71 and has a spiral hole (spiral hole) 72 that opens downward formed on the inside.

[0098] The hole forming portion 73, which constitutes part of this model M, is a support-requiring portion MO that requires support by the support S shown in Figures 19 (c) and (d) so that it does not collapse under its own weight when being modeled by the 3D printer 1 (during modeling).

[0099] 19(c) and 19(d) is made up of a plate-like spiral portion 75 whose width (vertical dimension) gradually increases from the outer periphery toward the center. As is clear from FIG. 19(c), this spiral portion 75 has a perfect circular shape in plan view, but is not limited to this and may have other shapes, such as an elliptical shape.

[0100] Such a support (support pattern) S can be designed, for example, by applying an Archimedes' spiral, and the continuous function that forms the basis of the design is expressed in parametric terms as shown below, and a specific design method is shown, for example, in Figure 20. In Figure 20, (1) is a diagram showing the process of creating a three-dimensional Archimedes' spiral, (2) is a diagram showing the process of drawing the Archimedes' spiral corresponding to (1) on a plane, (3) is a diagram showing the process of connecting (1) and (2) with a surface loft, (4) is a diagram showing the process of thickening and solidifying using the nozzle diameter, and (5) is a diagram showing the process of trimming as necessary.

[0101] X ｔ =t・cos(t) Y ｔ =t・sin(t) Z ｔ = t

[0102] Next, model M shown in Figures 21(a) and (b) is, for example, a lid body having a perfect circular shape, and similar to the one shown in Figure 2, has a cylindrical portion 76 and a disk-shaped portion 77 integrally formed on the inner surface of the upper end of this cylindrical portion 76.

[0103] The disk-shaped portion 77 that constitutes part of this model M is a support-requiring portion MO that requires support by the supports S shown in Figures 21(c) and (d) and Figure 22 so that it does not collapse under its own weight when being modeled by the 3D printer 1 (during modeling).

[0104] The support S shown in Figures 21(c) and (d) and Figure 22, like that shown in Figure 6, etc., has an inner cylindrical portion (cylindrical portion) 81, an outer cylindrical portion 82 located at the outermost position, and a plurality of plate-shaped connecting portions (extending portions) 83 that extend radially outward from the inner cylindrical portion 81 to connect the two cylindrical portions 81, 82.

[0105] In addition, this support S has multiple, for example two, small-diameter cylindrical portions 86, 87 which are additional cylindrical portions located inside the inner cylindrical portion 81, and these cylindrical portions 86, 87 are connected to the inner cylindrical portion 81 via a connecting portion 88 which is cross-shaped when viewed in a plane.

[0106] Furthermore, the support S has a plurality of, for example, three intermediate cylindrical portions 91, 92, and 93 located between the inner cylindrical portion 81 and the outer cylindrical portion 82 so as to intersect with each connecting portion 83. Note that each of the cylindrical portions 81, 82, 86, 87, 91, 92, and 93 of the support S is cylindrical, but the cylindrical portions are not limited to this shape, as will be described later.

[0107] Next, model M shown in Figures 23(a) and (b) is, for example, a square-shaped lid body, and is equipped with a rectangular cylindrical portion 96 and a square plate-shaped portion 97 integrally formed on the inner surface of the upper end of this cylindrical portion 96.

[0108] The plate-shaped portion 97 that constitutes part of this model M is a support-requiring portion MO that requires support by the support S shown in Figures 23(c) and (d) and Figure 24 so that it does not collapse under its own weight when being modeled by the 3D printer 1 (during modeling).

[0109] The support S shown in Figures 23(c) and (d) and Figure 24, like that shown in Figure 6, etc., has an inner cylindrical portion (cylindrical portion) 101, an outer cylindrical portion 102 located on the outermost side, and a plurality of plate-shaped connecting portions (extending portions) 103 extending radially outward from the inner cylindrical portion 101 to connect the two cylindrical portions 101, 102.

[0110] The support S also has a plurality of additional cylindrical portions 104, 105, for example, located inside the inner cylindrical portion 101. The additional cylindrical portion 104 is connected to the inner cylindrical portion 101 via a plurality of connecting portions 108 located radially. On the other hand, the additional cylindrical portion 105 is not connected to the additional cylindrical portion 104, but is arranged inside the additional cylindrical portion 104 as a separate body.

[0111] Furthermore, this support S has a plurality of, for example, two intermediate cylindrical portions 106, 107 located between the inner cylindrical portion 101 and the outer cylindrical portion 102 so as to intersect with each connecting portion 103. Note that in this support S, the additional cylindrical portions 104, 105 are triangular cylindrical, the inner cylindrical portion 101 is cylindrical, and the outer cylindrical portion 102 and the intermediate cylindrical portions 106, 107 are square cylindrical, but again, they are not limited to the shapes shown in the drawings and can be any cylindrical shape.

[0112] Next, model M shown in Figures 25(a) and (b) is, for example, a circular lid body, and is provided with a short, cylindrical columnar portion 111 and an annular plate-like portion 112 integrally formed on the outer peripheral surface of the upper end of this columnar portion 111.

[0113] The plate-shaped portion (flange portion) 112 that constitutes part of this model M is a support-requiring portion MO that requires support by the supports S shown in Figures 25(c) and (d) and Figure 26 so that it does not collapse under its own weight when being modeled by the 3D printer 1 (during modeling).

[0114] The support S shown in Figures 25(c) and (d) and Figure 26, like that shown in Figure 6, etc., has an inner cylindrical portion (cylindrical portion) 116, an outer cylindrical portion 117 located at the outermost position, and a plurality of plate-shaped connecting portions (extending portions) 118 that extend radially outward from the inner cylindrical portion 116 and connect both cylindrical portions 116, 117.

[0115] The support S also has one additional cylindrical portion 119 located inside the inner cylindrical portion 116, but this additional cylindrical portion 119 is not connected to the inner cylindrical portion 116 and is separate from the inner cylindrical portion 116. The inner peripheral surface of this additional cylindrical portion 119 is formed in a shape that corresponds to the outer peripheral surface of the columnar portion 111 of the model M.

[0116] Furthermore, this support S has one intermediate cylindrical portion 120 located between the inner cylindrical portion 116 and the outer cylindrical portion 117 so as to intersect with each connecting portion 118. Note that in this support S, each of the cylindrical portions 116, 117, 119, and 120 is cylindrical.

[0117] 27(a) and (b), a model M is a grease trap body having, for example, a box shape with an open top, and includes a rectangular cylindrical portion 121 having a bottom and a rectangular annular plate portion (flange portion) 122 integrally formed on the outer peripheral surface of the upper end of the cylindrical portion 121. A generally cross-shaped bulge 124 is formed on the bottom plate 123 of the cylindrical portion 121 so as to bulge upward, and the lower end of an oil-water separation member 125, which is an attachment member, is attached to the bulge 124 by fitting.

[0118] The bulge portion 124 and the plate-like portion (flange portion) 122 that constitute part of this model M are support-requiring portions MO that require support by two separate supports S (S1, S2) shown in Figures 27 and 28 so that they do not collapse under their own weight when being modeled by the 3D printer 1 (during modeling).

[0119] Furthermore, support S1 has a plate-like bottom (base) 126 shaped to correspond to bulging portion 124 of model M, and a plurality (e.g., 10 or more) of cylindrical portions 127 erected on the upper surface of bottom 126. Furthermore, support S2 has a rectangular annular plate-like bottom (base) 128 shaped to correspond to plate-like portion (flange) 122 of model M, and a plurality (e.g., 5 or more) of cylindrical portions 129 erected on the upper surface of bottom 128. In other words, each of supports S1 and S2 has a support shape that does not have radial elements (extending portions) extending radially from a cylindrical portion.

[0120] Next, model M shown in Figures 29(a) and (b) is a component (a figurine, a pet grave, etc.) that resembles an animal such as a seal, and comprises a cylindrical portion 131 and a dome-shaped plate portion 132 that is integrally formed on the upper end side of this cylindrical portion 131.

[0121] The plate-like portion 132 constituting part of this model M is a support-requiring portion MO that needs to be supported by supports S shown in Figures 29(c) to 29(e) and 30 so as not to collapse under its own weight when (during) modeling by the 3D printer 1. Note that Figure 31 shows a rough model W1 consisting of the model M and supports S.

[0122] Similar to the support S shown in Figure 6, etc., this support S has an inner cylindrical portion (cylindrical portion) 136, an outer cylindrical portion 137 located at the outermost position, and a plurality of plate-shaped connecting portions (extending portions) 138 extending radially outward from the inner cylindrical portion 136 to connect the two cylindrical portions 136, 137.

[0123] The support S also has an additional cylindrical portion 139 located inside the inner cylindrical portion 136, and a rod-shaped portion 140 (which may be a cylindrical or rectangular cylindrical portion, for example) that is a round rod-shaped central axis portion located inside the additional cylindrical portion 139. In the support S, the cylindrical portions 136, 137, and 139 are all cylindrical. The shape of the upper surface of the support S is dome-shaped, corresponding to the plate-shaped portion 132 of the model M.

[0124] 32 has an undercut shape, and is molded such that the support-requiring portions MO of the model M are supported by supports S. In this case, too, the method for manufacturing a molded object according to this embodiment allows the supports S to be easily removed from the rough molded object W1 after molding, but this removal requires that part of the supports S be destroyed. Therefore, unlike the case described above, the removed supports S cannot be reused as placement pieces.

[0125] The fused deposition model 3D printer, which is a modeling device for producing (shaping) the various models described above, may be a large-scale pellet-type 3D printer with a nozzle diameter φ of 10 mm or more, and this large-scale 3D printer can use inexpensively obtainable general pellet-shaped thermoplastic resin (which may be recycled pellet material, etc.) as the modeling material, rather than a dedicated filament resin.

[0126] Furthermore, the object manufacturing device is not limited to a fused deposition model 3D printer, but may also be, for example, a stereolithography (DLP or SLA) 3D printer.

[0127] Furthermore, the three-dimensional objects formed using the object manufacturing device are not limited to those described above, but may be, for example, housings, joints, boxes, etc., and the type, shape, size, etc. of the object are arbitrary.

[0128] Furthermore, the object manufacturing device is not limited to a configuration in which the modeling head (discharge means) having a nozzle for discharging the modeling material is movable in the X-axis direction and the Z-axis direction and the modeling table is movable in the Y-axis direction, but may be configured so that the modeling head is movable in at least three dimensions relative to the modeling table. For example, the device may be configured so that the modeling head is movable in the X-axis direction and the Y-axis direction and the modeling table is movable in the Z-axis direction, or the device may be configured so that the modeling head is attached to the tip of a robot arm (preferably the robot arm of a six-axis robot) and is movable in any direction including the three directions of the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0129] Furthermore, the dimensions of the specified gap during the modeling process should be such that resin dripping (dripping of modeling material) due to its own weight is minimized and the clearance (slight gap height dimension) is such that the lower surface of the part of the model that requires support and the upper surface of the support that supports the part that requires support do not become firmly integrated (adhered) with each other.

[0130] Furthermore, the support for the rough molded object in the molding process may have, for example, no outer cylindrical portion, no additional cylindrical portion, or no radially extending portion.

[0131] Furthermore, the additional cylindrical portion located inside the inner cylindrical portion of the support may be configured either to be connected to the inner cylindrical portion (integral configuration) or not to be connected to the inner cylindrical portion (separate configuration), and the number and shape of the additional cylindrical portions may also be arbitrary.

[0132] DESCRIPTION OF SYMBOLS 1 Fused deposition modeling 3D printer as a model manufacturing device 11 Nozzle 20 Predetermined gap 31, 81, 101, 116, 136 Inner cylindrical portion as a cylindrical portion 32, 82, 102, 117, 137 Outer cylindrical portion 33, 83, 103, 118, 138 Connecting portion as an extension portion 36, 37, 86, 87, 104, 105, 119, 139 Additional cylindrical portion 51, 63, 68, 75 Spiral portion 126, 128 Bottom portion 127, 129 Cylindrical portion H Predetermined gap dimension (gap height dimension) φ Nozzle opening diameter (nozzle diameter) W Model W1 Roughly modeled object M Model MO Portion requiring support (overhang portion) S Support

Claims

1. A method for manufacturing a three-dimensional object using a fused deposition modeling 3D printer having a nozzle that ejects modeling material melted by heat from an ejection port, the method comprising: a modeling process for manufacturing a rough object having a model to be the object and a support that supports a part of the model that requires support; and a removal process for removing the support from the rough object by separating the model and the support after the modeling process; wherein, in the modeling process, when the part requiring support of the model that contacts the upper surface of the support is modeled, a specified gap is formed between the ejection port of the nozzle and the upper surface of the support compared to when the modeling material is ejected onto the upper surface of the model that has already been modeled, and the upper surface of the support is brought into contact with the lower surface of the part requiring support of the model by deformation due to the weight of the modeling material that hardens after ejection, thereby manufacturing the object.

2. The method for manufacturing a molded object according to claim 1, characterized in that, when the dimension of the predetermined gap in the molding process is H and the opening diameter of the nozzle outlet of a fused deposition model 3D printer is φ, φ / 2≦H≦φ is satisfied.

3. A method for manufacturing a molded object as claimed in claim 1 or 2, characterized in that the support for the rough molded object in the molding process has a cylindrical portion and a plurality of extension portions extending radially from the cylindrical portion.

4. A method for manufacturing a molded object as described in claim 1 or 2, characterized in that the support for the rough molded object in the molding process has an inner cylindrical portion and an outer cylindrical portion, and a connecting portion connecting the inner cylindrical portion and the outer cylindrical portion.

5. The method for manufacturing a molded object according to claim 3, characterized in that the support for the rough molded object in the molding process has an additional cylindrical portion located inside the cylindrical portion.

6. The method for manufacturing a molded object according to claim 3, characterized in that the cylindrical portion forms a closed curve.

7. The method for manufacturing a molded object according to claim 1 or 2, characterized in that the support for the rough molded object in the molding process has a plate-shaped spiral portion.

8. The method for manufacturing a molded object according to claim 1 or 2, characterized in that the support for the rough molded object in the molding process has a cylindrical portion.

9. A method for manufacturing a molded object as claimed in claim 1 or 2, characterized in that the support for the rough molded object in the molding process has a bottom and a plurality of cylindrical parts erected on the bottom.

10. The method for manufacturing a molded object according to claim 1 or 2, characterized in that the supports removed in the removing step can be reused as support members for supporting parts of the model that require support when manufacturing the same molded object.

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