JP7484006B1 - Method for manufacturing objects - Google Patents

Abstract

[Problem] To provide a method for manufacturing a molded object that allows easy removal of supports. [Solution] The method for manufacturing a molded object includes a molding step and a removal step. The molding step is a step for molding a rough object W1 having a model M to be the molded object and supports S that support the support-requiring portion MO of the model M. The removal step is a step for removing the supports S from the rough object W1 by separating the model M and the supports S after the molding step. Then, in the molding step, the support-requiring portion MO of the model M is molded while forming a predetermined gap 20 between the supports S and the support-requiring portion MO of the model M. [Selected Figure] Figure 4

Description

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

In recent years, fused deposition modeling 3D printers, for example, have become widely known as modeling devices for producing three-dimensional objects (see, for example, Patent Document 1).

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).

JP 2000-500709 A

However, the supports that support the parts of the model that need support during printing are no longer necessary after printing, so it is necessary to separate the two and remove the supports, but this removal is often difficult.

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

The method for manufacturing a molded object according to an embodiment of the present invention is a method for manufacturing a three-dimensional object using a molded object manufacturing device, and includes a manufacturing process for manufacturing a rough object having a model that will become the molded 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 manufacturing process. In the manufacturing process, the part that requires support is molded while forming a predetermined gap between the support and the part of the model that requires support.

In the above-mentioned object manufacturing method, when the dimension of the predetermined gap in the object manufacturing process is H and the opening diameter of the nozzle in the object manufacturing device is φ, the relationship φ/2≦H≦φ may be satisfied.

In the above-mentioned method for manufacturing a molded object, the support for the rough molded object in the molding process may have a cylindrical portion and a plurality of extension portions extending radially from the cylindrical portion.

In the above-mentioned method for manufacturing a molded object, the support for the rough molded object in the molding process 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.

In the above-mentioned method for manufacturing a molded object, the support for the rough molded object in the molding process may include an additional cylindrical portion located inside the cylindrical portion.

In the above-mentioned method for manufacturing a molded object, the cylindrical portion may be a closed curve.

In the above-mentioned method for manufacturing a model, the support for the rough model in the modeling process is formed by a continuous function.

In the above-mentioned method for manufacturing a molded object, the support for the rough molded object in the molding process may have a plate-shaped spiral portion.

In the above-mentioned method for manufacturing a molded object, the support for the rough molded object in the molding process may have a cylindrical portion.

In the above-mentioned method for manufacturing a molded object, the support for the rough molded object in the molding process may have a bottom and a number of cylindrical parts standing on the bottom.

In the above-described method for manufacturing a molded object, the support removed in the removal step may be reusable as a support member for supporting a part of the model that requires support when manufacturing the same molded object.

In the above-mentioned object manufacturing method, the object manufacturing device may be a fused deposition model 3D printer.

The object manufacturing device according to the embodiment of the present invention is used in the object manufacturing method described above.

According to an embodiment of the present invention, the support can be easily removed.

1A and 1B are schematic diagrams illustrating a fused deposition modeling 3D printer, which is an apparatus for manufacturing an object according to one embodiment of the present invention, in which FIG. 1A is an overall front view, and FIG. 1B is an enlarged view of a modeling head. 1A is a perspective view of a molded object (model) manufactured using the 3D printer, FIG. 1B is a plan view, and FIG. 1C is a cross-sectional view taken along line A-A. 5A to 5C are diagrams showing a modeling process, and FIG. 5D is a diagram showing a removal process, illustrating a method for manufacturing the above-mentioned model. 5A and 5B are explanatory views of a predetermined gap in the molding process. FIG. 4 is a cross-sectional view of a rough object produced in the manufacturing process. FIG. 4 is a partially cutaway plan view of a rough object produced in the manufacturing process. FIG. 2 is a partially cutaway perspective view of a rough object produced in the molding process; 4A is a perspective view of a support (a supporting piece that is a supporting member) removed in the removing step, and FIG. 4B is a diagram of a modeling step using the support. 6A and 6B are photographs of a prototype of a molded object (satisfying φ/2≦H≦φ). Photographs of prototypes of objects (not satisfying φ/2≦H≦φ) are shown in (a) to (c). 1A is a perspective view of another object (model) manufactured using the 3D printer, FIG. 1B is a plan view, and FIG. 1C is a cross-sectional view taken along line A-A. FIG. 5A to 5E are diagrams illustrating a modeling process, and FIG. 5F is a diagram illustrating a removal process, illustrating a method for manufacturing the above-mentioned model. FIG. 4 is a cross-sectional view of a rough object produced in the manufacturing process. FIG. 2 is a partially cutaway perspective view of a rough object produced in the molding process; FIG. 13 is a perspective view of a support (a support piece that is a supporting member) removed in the removal step. 11A and 11B are diagrams showing another example of such a support manufactured in the same molding process, in which FIG. 13A and 13B are diagrams showing still another example of the model and the support, in which (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. 13A and 13B are diagrams showing still another example of the model and the support, in which (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. 13A and 13B are diagrams showing still another example of the model and the support, in which (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. FIG. 20 is an explanatory diagram of the support shown in FIG. 19 . 13A and 13B are diagrams showing still another example of the model and the support, in which (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. FIG. 22 is an enlarged plan view of the support shown in FIG. 21 . 13A and 13B are diagrams showing still another example of the model and the support, in which (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. FIG. 24 is an enlarged plan view of the support shown in FIG. 23. 13A and 13B are diagrams showing still another example of the model and the support, in which (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. FIG. 26 is an enlarged plan view of the support shown in FIG. 25 . 13A and 13B are diagrams showing yet another example of a model and support. 27A, 27B, 27C, 27D, 27E, 27F, 27G, 27G, and 27G, respectively. FIG. 13A and 13B are diagrams showing still another example of a model and a support, in which (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. FIG. 30 is an enlarged plan view of the support shown in FIG. 29. 30A, 30B, 30C, and 30D are diagrams showing a rough model made up of the model and support shown in FIG. 29, in which (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. FIG. 13 is a schematic cross-sectional view of a rough molded object including a model and a support according to still another example of the model and the support.

One embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, 1 is a fused deposition modeling 3D printer, which is a modeling device. This fused deposition modeling 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 (dissolved) by heat, one layer at a time, based on 3D modeling data.

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

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

In addition, 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 FIG. 1, and may be configured in such a way that the modeling head 4 moves at least three-dimensionally relative to the modeling table 5).

The 3D printer 1 also includes a first drive unit 6 that moves the modeling head 4 in the X-axis direction and 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.

Then, based on the control by the control unit 8, the modeling head 4 moves three-dimensionally relative to the modeling table 5, while resin (molten resin) is ejected from the nozzle 11 of the moving modeling head 4. When 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.

However, depending on the shape of the desired object W, as described below, 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 created.

In other words, when supports S are required, a rough object W1 consisting of a model M and supports S is first produced, and then the supports S are removed from the rough object W1 to obtain the desired object W.

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 molten by heat from a heating means (not shown) in the modeling head 4 from an ejection port 10.

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 modeling head 4, and is discharged (exhausted) downward from the outlet 10 of one nozzle 11 for discharging the modeling material. Note that the heating means and extrusion means may be provided outside the modeling head 4, rather than inside it.

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).

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

The 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 that is integrally formed on the inner circumferential surface of the upper end of the cylindrical portion 16.

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

Figure 3 is a schematic diagram of a method for manufacturing the object W shown in Figure 2 (one 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.

The first process, the modeling process, is a process in which resin (dissolved resin made of one type of modeling material) is discharged from the outlet 10 of the nozzle 11 of the modeling head 4, which moves three-dimensionally relative to the modeling table 5, and layered on the modeling table 5 to form (create) a three-dimensional rough model W1 on the modeling table 5, the rough model W1 having a model M that will ultimately become the desired model W, and a support S that supports the parts MO of the model M that require support from below during modeling, as shown in Figures 3(a) to (c).

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 FIG. 3(d).

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 a predetermined gap 20 is temporarily formed (left open) between the support S and the support-requiring portion MO of the model M.

More specifically, as shown in FIG. 4(a), during the modeling process, a predetermined gap (constant gap) 20 in the height direction is temporarily formed between the upper surface 21 of the already modeled support S and the lower surface 22 of the support-requiring part MO of the model M being modeled (the lower surface of the linear molten resin immediately after being discharged from the outlet 10 of the nozzle 11 during horizontal movement), while a layer of the lower surface of the support-requiring part MO (one layer that will become the lower surface of the support-requiring part MO, which is the disk-shaped part 17) is modeled.

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 model 3D printer 1.

Therefore, for example, when φ is 0.4 mm as in this embodiment, H is a dimension within the range of 0.2 mm to 0.4 mm. In other words, the dimension H of the specified 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 ejects the modeling material (dissolved resin) and equal to or less than the opening diameter φ.

The gap 20 temporarily formed in the modeling process is filled almost entirely by the resin dripping as the resin deforms (sagging) downwards due to its own weight, as shown in Figures 4(b) and 5. Note that the resin dripping is omitted in Figure 3 (as is the case in Figure 12).

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

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

However, the contact portion of the resin supported by the upper surface 21 (the lower surface of the resin drip) does not firmly become integrated (adhered) with the upper surface 21 of the support S even after it hardens and solidifies, which makes it easier to remove the support S in the removal process after the modeling process.

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

Furthermore, it is preferable that the dimension H of the predetermined gap 20 for preventing the model M and the support S from being firmly integrated (adhered) in this way satisfies 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 part of the part MO of the model M that requires support will collapse.

In short, when the relationship φ/2≦H≦φ is satisfied, the collapse of the model M can be prevented while minimizing resin dripping, and the model M and the support S do not become tightly integrated (adhered).

Therefore, the model M and the support S can be easily separated in the removal process. For example, as shown in FIG. 3(d), an operator can simply lift the model M upwards by hand on the modeling table 5 without using any tools (tool-less), and the model M can be easily separated from the support S (the support that is layer-modeled in direct contact with the upper surface of the modeling table 5) on the modeling table 5. In other words, the support S can be extremely easily removed from the model M with a single action of simply lifting the model M, and the support S can be easily removed from the rough model W1.

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

The dimension D of this gap 25 is, for example, the same as the opening diameter φ of the nozzle 11, for example, 0.4 mm. However, D does not necessarily have to be equal to φ, and the dimension D of the gap 25 may be, for example, 0.5 mm.

In the method for manufacturing a molded object according to this embodiment, as shown in FIG. 6 and FIG. 7, the support S of the rough molded object W1 molded in the molding 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 located outside the inner cylindrical portion 31 at a predetermined distance from the inner cylindrical portion 31 and is located close to the inner peripheral surface 27 of the model M and has a shape that corresponds to the inner peripheral surface 27 of the model M, i.e., an outer cylindrical portion 32 that is annular in plan view, i.e., annular in plan view, centered on the center point P of the inner cylindrical portion 31, and a connecting portion (connecting plate-shaped portion) 33 that is a plurality of plate-shaped extension portions that are located radially around the center point P of the inner cylindrical portion 31 so as to extend radially outward from the inner cylindrical portion 31 and integrally connect the inner cylindrical portion 31 and the outer cylindrical portion 32 in a planar line of sight.

The support S has a smaller diameter than the inner cylindrical portion 31 and has a plurality of, for example, two small diameter cylindrical portions 36, 37 that are additional cylindrical portions that are annular in plan view and located inside the inner cylindrical portion 31, i.e., annular in plan view with the center point P of the inner cylindrical portion 31 as the center. In other words, the planar shape (support pattern) of the support S is not restricted to a single stroke, and the small diameter cylindrical portions 36, 37 on the central side are not connected to the inner cylindrical portion 31.

The small diameter cylindrical portions 36, 37, the inner cylindrical portion 31, and the outer cylindrical portion 32 are concentric and are all formed in a cylindrical shape (a cylindrical shape with an axial direction in the vertical direction and open on both the top and bottom) centered on a central axis L that extends in the vertical direction (Z-axis direction) passing through the same center point P (see Figure 5).

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 plan view (the same goes for 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 which does not touch or intersect with itself on the way from the starting point to the end point. Single closed curves include circles and ellipses. Single closed curves also include polygons such as triangles and rectangles, as well as cardioids (heart shapes). 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.

As shown in FIG. 6, the angle θ between the 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 on the inside (inner peripheral side) of the inner cylindrical portion 31 is two, but it may be one or three or more, for example.

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 and 37.

Therefore, after the support S is removed, it can be reused as a support piece (support member) that supports the part MO of the model M that requires support 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.

In other words, when reusing the removed support S shown in FIG. 8(a) as a placement piece to repeatedly manufacture (form) the object (model M) W shown in FIG. 2, as shown in FIG. 8(b), the formation operation is stopped once just before the support-requiring portion MO of the model M is formed, and the support S as a placement piece (a base that supports the support-requiring portion MO) is placed on the formation table 5, and then the formation operation is resumed to form the support-requiring portion MO of the model M on the placement piece.

In this way, by reusing the support S as a placement piece, support modeling is not performed, and in the support reuse modeling process in which only the model M is modeled, similar to the modeling process described above, a specified 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.

As a result, even in this case, the model M and the support (placement piece) S are not firmly integrated (adhered), 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 used repeatedly any number of times.

The method for manufacturing a model according to the present embodiment described above includes a manufacturing process for manufacturing a rough model W1 having a model M that will become the model W and supports S that support the support-requiring portion MO of the model M, and a removal process for removing the supports S from the rough model W1 by separating the model M and the supports S after the manufacturing process. In the manufacturing process, the support-requiring portion MO of the model M is manufactured while forming a small predetermined gap 20 between the supports S and the support-requiring portion MO of the model M. This facilitates the separation of the model M and the supports (support structures) S in the removal process, and allows the supports S to be easily removed from the rough model W1, thereby improving the manufacturability of the model W.

In addition, support marks are less likely to remain in the areas MO of the model W that require support, improving the quality of the model W.

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, by satisfying φ/2≦H≦φ, not only can the collapse of the model M be appropriately prevented in the modeling process, 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.

Furthermore, the support S of the rough object W1 in the modeling process has a cylindrical inner tubular portion 31 that is annular in plan view, a cylindrical outer tubular portion 32 that is located outside the inner tubular portion 31 and has a shape that corresponds to the cylindrical inner peripheral 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 form a line of sight in plan view to 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.

In addition, 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 supports easily collapsing during modeling. However, in the manufacturing method of this embodiment, such problems do not occur because a support S of a predetermined shape is used.

Furthermore, in the manufacturing method of this embodiment, it is possible to obtain supports S that can be easily removed in the removal process without being limited by modeling software or modeling machines. In other words, 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, so it can be applied to any fused deposition modeling machine.

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

Here, Figures 9(a) and (b) are photographs of a prototype of the object W (one that satisfies φ/2≦H≦φ), and Figures 10(a) to (c) are photographs of a prototype of the object W (one that does not satisfy φ/2≦H≦φ).

The lid of the model 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.

The prototype shown in Figure 9(a) has H = 0.2 mm and D = 0.4 mm. In this case, there was almost no resistance, and by simply lifting the model M by hand above the modeling table 5, the model M could be easily separated from the support S on the modeling table 5. Furthermore, although some support marks are visible on the parts MO of the model M that require support, they are not uneven, and there is no problem with the quality of the model W, and there is no stacking abnormality (collapse). Furthermore, the separated support S can be reused as a placement piece.

The prototype shown in Figure 9(b) has 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 above the modeling table 5. Furthermore, there are some signs of resin dripping in the areas MO of the model M that require support, but this does not pose a problem for the quality of the model W and there are no stacking abnormalities (collapse). Furthermore, the separated support S can be reused as a placement piece.

On the other hand, the prototype shown in FIG. 10(a) has H = 0.1 mm and D = 0.4 mm. In this case, the model M could not be separated by simply lifting it by hand, and after removing the rough model W1 from the modeling table 5, the model M and the support S were separated using a pair of needle-nose pliers, but there was some resistance during this process. In addition, there were traces of deformation on the support S when it was held with the needle-nose pliers, and this support S cannot be reused as a placement piece.

The prototype shown in Figure 10(b) has 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 above the modeling table 5. However, partial stacking abnormalities (collapse) occurred in the part MO of the model M that required support.

Furthermore, the prototype shown in Figure 10(c) is without support, and in this case, stacking abnormalities (collapse) occurred in the part MO of model M that required support.

Therefore, these prototypes confirmed that it is preferable to satisfy φ/2≦H≦φ.

In the above embodiment, the case of manufacturing the object W shown in FIG. 2 has been described, but the present invention is not limited to this. For example, the object W shown in FIG. 11 can also be manufactured in a similar manner, and in this case, the support S can also be easily removed, and similar effects can be achieved.

That is, the object W shown in FIG. 11 is, for example, a stepped, oblique cap-shaped lid body, and includes a lower cylindrical portion 41, an upper cylindrical portion 42 that is integrally formed with the inner peripheral 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 that is integrally formed with the inner peripheral surface of the upper end of the upper cylindrical portion 42.

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

FIG. 12 is a diagram that shows an outline of a method for manufacturing a molded object W shown in FIG. 11 (one example of a manufacturing method according to this embodiment), in which (a) to (e) are diagrams of the molding process, and (f) is a diagram of the removal process.

As in the case of manufacturing the object W shown in FIG. 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 as to satisfy φ/2≦H≦φ. Note that the predetermined gap 20 is almost entirely filled by resin dripping due to its own weight (see FIG. 13).

The support S produced by additive manufacturing in the manufacturing process shown in FIG. 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 FIGS. 13 to 15, in the same manner as in the case of producing the object W shown in FIG. 2 described above. The outer cylindrical portion 32, which has a shape corresponding to the inner peripheral 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.

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.

The support S according to this embodiment is not limited to those shown in Figs. 8 and 15, but may have a plate-shaped spiral portion (spiral plate portion) 51 that is spiral in plan view (e.g., Archimedes' spiral, etc.), as shown in Fig. 16, for example.

That is, the support S shown in FIG. 16 is made up of only one continuous plate-like spiral portion 51, and has a cross-sectional shape that is a figure 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, for example, 0.4 mm.

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

_Xt = t cos(t)
_Yt = t sin(t)

The support S shown in FIG. 16 can also be used to produce a cap-shaped object W as shown in FIG. 2 in a similar manner, and in this case too, the support S can be easily removed, providing similar effects.

In addition, because this type of 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, allowing for a reduction in modeling time.

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 according to 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 any case, the same effect can be achieved, such as the support S being easily removable.

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

_Xt = at cos(t)
_Yt = bt sin(t)

The disk-shaped portion (upper plate portion) 62 that constitutes part of the model M is a support-required 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 modeling (during modeling) using the 3D printer 1.

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 plate-shaped spiral portion 51 having a perfect circle shape shown in Figure 16 above.

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 have a five-pointed star shape or an eight-pointed star shape, etc.), and is equipped with a six-pointed star shaped cylindrical portion 66 and a six-pointed star shaped plate portion 67 that is integrally formed on the inner peripheral surface of the upper end portion of this cylindrical portion 66.

The plate-like portion (upper plate portion) 67 that constitutes part of this model M is a support-required 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 modeling (during modeling) using the 3D printer 1.

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

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 provided on the inner circumference side of this cylindrical portion 71 and has a spiral hole (spiral hole) 72 formed on the inside that opens downward.

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

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

Such a support (support pattern) S can be designed, for example, by applying Archimedes' spiral. The continuous function that is the basis of the design is shown below in parametric notation, and the specific design method is, for example, as shown in Figure 20.

_Xt = t cos(t)
_Yt = t sin(t)
_Zt = t

Next, model M shown in Figures 21(a) and (b) is, for example, a circular lid, and like the one shown in Figure 2, has a cylindrical portion 76 and a disk-shaped portion 77 that is integrally formed on the inner circumferential surface of the upper end of this cylindrical portion 81.

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

The support S shown in Figs. 21(c) and (d) and Fig. 22, like that shown in Fig. 6 etc., has an inner cylindrical portion (cylindrical portion) 81, an outer cylindrical portion 82 located on the outermost side, and a number of plate-shaped connecting portions (extending portions) 83 that extend radially outward from the inner cylindrical portion 81 and connect both cylindrical portions 81, 82.

The support S also has multiple, for example two, small diameter cylindrical sections 86, 87 that are additional cylindrical sections located inside the inner cylindrical section 81, and these cylindrical sections 86, 87 are connected to the inner cylindrical section 81 via a connecting section 88 that is cross-shaped in plan view.

Furthermore, the support S has multiple, for example three, intermediate cylindrical portions 91, 92, 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, 93 of the support S is cylindrical, but the cylindrical portions are not limited to this shape, as described below.

Next, model M shown in Figures 23(a) and (b) is, for example, a square-shaped lid, and includes a rectangular cylindrical portion 96 and a square plate portion 97 that is integrally formed on the inner peripheral surface of the upper end of the cylindrical portion 96.

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

The support S shown in Figs. 23(c) and (d) and Fig. 24, like that shown in Fig. 6 etc., has an inner cylindrical portion (cylindrical portion) 101, an outer cylindrical portion 102 located on the outermost side, and a number of plate-shaped connecting portions (extending portions) 103 that extend radially outward from the inner cylindrical portion 101 and connect both cylindrical portions 101, 102.

The support S also has multiple, for example two, additional cylindrical parts 104 and 105 located inside the inner cylindrical part 101. The additional cylindrical part 104 is connected to the inner cylindrical part 101 via multiple connecting parts 108 located radially. On the other hand, the additional cylindrical part 105 is not connected to the additional cylindrical part 104, and is arranged as a separate part inside the additional cylindrical part 104.

Furthermore, this support S has multiple, for example two, intermediate cylindrical parts 106, 107 located between the inner cylindrical part 101 and the outer cylindrical part 102 so as to intersect with each connecting part 103. Note that in this support S, the additional cylindrical parts 104, 105 are triangular cylindrical, the inner cylindrical part 101 is cylindrical, and the outer cylindrical part 102 and the intermediate cylindrical parts 106, 107 are rectangular cylindrical, but again, they are not limited to the shapes shown in the figures and can be any cylindrical shape.

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

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

The support S shown in Figs. 25(c) and (d) and Fig. 26, like that shown in Fig. 6 etc., has an inner cylindrical portion (cylindrical portion) 116, an outer cylindrical portion 117 located on the outermost side, and a number 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.

The support S also has an 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 into a shape that corresponds to the outer peripheral surface of the columnar portion 111 of the model M.

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

Next, model M shown in Figures 27(a) and (b) is a grease trap main body that is, for example, box-shaped with an open top, and includes a rectangular, bottomed, cylindrical tubular section 121 and a rectangular, annular plate section (flange section) 122 that is integrally formed on the outer circumferential surface of the upper end of this tubular section 121. In addition, a roughly cross-shaped bulge section 124 is formed on the bottom plate 123 of the tubular section 121 in a bulging shape toward the top, and the lower end of an oil-water separation member 125, which is an attachment member, is attached to this bulge section 124 by fitting.

The bulge 124 and plate-like portion (brim portion) 122 that constitute part of this model M are support-required parts 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 modeling (during modeling) using the 3D printer 1.

Support S1 has a plate-shaped bottom (base) 126 that is shaped to correspond to the bulge 124 of model M, and a plurality (e.g., 10 or more) of cylindrical parts 127 standing on the top surface of the bottom 126. Support S2 has a rectangular, annular, plate-shaped bottom (base) 128 that is shaped to correspond to the plate-shaped part (brim) 122 of model M, and a plurality (e.g., 5 or more) of cylindrical parts 129 standing on the top surface of the bottom 128. In other words, each of supports S1 and S2 has a support shape that does not have radial elements (extensions) that extend radially from the cylindrical parts.

Next, model M shown in Figures 29(a) and (b) is a component (ornament, pet grave, etc.) that imitates an animal such as a seal, and has 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.

The plate-like portion 132 that constitutes part of this model M is a support-required portion MO that requires support by supports S shown in Figs. 29(c) to (e) and 30 so that it does not collapse under its own weight when modeling (during modeling) using the 3D printer 1. Note that Fig. 31 shows a rough model W1 consisting of the model M and supports S.

This support S, like that shown in FIG. 6, has an inner cylindrical portion (cylindrical portion) 136, an outer cylindrical portion 137 located at the outermost position, and a number of plate-shaped connecting portions (extending portions) 138 that extend radially outward from the inner cylindrical portion 136 and connect both cylindrical portions 136, 137.

This support S also has an additional cylindrical portion 139 located inside the inner cylindrical portion 136, and a rod-shaped portion (which may be a cylindrical or square cylindrical portion, for example) 140 that is a round bar-shaped central axis portion located inside the additional cylindrical portion 139. In this support S, each of the cylindrical portions 136, 137, and 139 is cylindrical. The shape of the upper surface of this support S is a dome shape that corresponds to the plate-shaped portion 132 of the model M.

Next, model M shown in FIG. 32 has an undercut shape, and the part MO of model M that requires support is supported by supports S when it is molded. Even in such a case, according to the molded object manufacturing method of this embodiment, the supports S can 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 support S described above, the removed supports S cannot be reused as placement pieces.

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

The object manufacturing device is not limited to a fused deposition model 3D printer, but may be, for example, a stereolithography (DLP or SLA) 3D printer.

Furthermore, the three-dimensional objects produced using the object production 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.

Furthermore, the object manufacturing device is not limited to a configuration in which a modeling head (discharge means) having a nozzle for discharging 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, a configuration in which 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 a configuration in which the modeling head is attached to the tip of a robot arm (for example, the robot arm of a six-axis robot is preferable) and can be moved in any direction including the three directions of the X-axis direction, the Y-axis direction, and the Z-axis direction.

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 bottom surface of the part of the model that needs support and the top surface of the support that supports the part that needs support are not firmly integrated (adhered) to each other (slight gap height dimension).

Furthermore, the support for the rough object in the molding process may be, for example, a configuration that does not have an outer cylindrical portion, a configuration that does not have an additional cylindrical portion, a configuration that does not have a radial extension portion, etc.

The additional cylindrical portion located inside the inner cylindrical portion of the support may be either connected to the inner cylindrical portion (integral configuration) or not connected to the inner cylindrical portion (separate configuration), and the number and shape of the additional cylindrical portions are also optional.

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 Rough model M Model MO Part requiring support (overhanging part)
S Support

Claims (10)

A method for manufacturing a three-dimensional object using a fused deposition modeling 3D printer having a nozzle that discharges a modeling material melted by heat from a discharge port, comprising:
a modeling step of forming a rough object having a model to be the object and supports for supporting portions of the model that require support;
a removing step of removing the support from the rough object by separating the model and the support after the modeling step,
In the modeling process, when modeling the support-requiring portion of the model that contacts the upper surface of the support, a distance between the discharge port of the nozzle and the upper surface of the support is formed by a predetermined gap larger than when the modeling material is discharged 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 support-requiring portion of the model by deformation due to the weight of the modeling material that hardens after being discharged.
A method for manufacturing a shaped object, comprising: 2. The method for manufacturing a molded object according to claim 1, wherein, when a dimension of the predetermined gap in the molding process is H and an opening diameter of an outlet of a nozzle in a fused deposition modeling 3D printer is φ, φ/2≦H≦φ is satisfied. The support for the rough model in the modeling process is
A cylindrical portion;
The method for manufacturing a molded object according to claim 1 or 2, further comprising: a plurality of extending portions extending radially from the cylindrical portion. The support for the rough model in the modeling process is
an inner tubular portion and an outer tubular portion;
The method for manufacturing a molded object according to claim 1 or 2, further comprising a connecting portion that connects the inner cylindrical portion and the outer cylindrical portion. The method for manufacturing a molded object according to claim 3 , wherein the support for the rough molded object in the molding step has an additional cylindrical portion located inside the cylindrical portion. The method for manufacturing a molded object according to claim 3 , wherein the cylindrical portion forms a closed curve. The method for manufacturing a molded object according to claim 1 or 2, wherein a support for the rough molded object in the molding step has a plate-shaped spiral portion. The method for manufacturing a molded object according to claim 1 or 2, wherein a support for the rough molded object in the molding step has a cylindrical portion. The support for the rough model in the modeling process is
The bottom and
The method for manufacturing a shaped object according to claim 1 or 2, further comprising: a plurality of cylindrical portions provided upright on the bottom portion. 3. The method for manufacturing a molded object according to claim 1, wherein the supports removed in the removing step can be reused as support members for supporting portions of the model that require support when the same molded object is manufactured.

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