JPH0584834A - Molding method of three dimensional shape - Google Patents

Abstract

PURPOSE:To provide a method capable of firmly positively supporting an optical curing layer, and simply efficiently carrying out a work for removing a formed molding from the molding table in a method of forming an optical curing layer by irradiating rays to optical curing resin and forming a desirable three dimensional shape in stacking a plurality of the optical curing layers. CONSTITUTION:An optical layer 40 that constitutes a three dimensional shape is formed on the molding table 20 via a supporting optical curing layer 42, and the supporting optical curing layer 42 is supported on the upper end of a supporting projection part of the male screw parts 32 and the like projected out on time upper surface of the molding table 20, wherein the support of the supporting projection parts 32 relative to the supporting optical curing layer 42 can prevent the supporting optical curing layer 42 from moving upward and the supporting optical curing layer 42 can also be dislodged without breakdown.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a three-dimensional shape, and more specifically, a method for molding and manufacturing an article having a three-dimensional shape using a photocurable resin which is cured by irradiation with light. It is about.

[0002]

2. Description of the Related Art A method of forming a three-dimensional shape using a photocurable resin can easily and accurately form a complicated three-dimensional shape without using a molding die or a special processing tool. As a method, it is considered to be used for manufacturing various product models and three-dimensional models, and specifically, for example, the method disclosed in JP-A-62-35966 is known.

FIG. 6 shows an example of a three-dimensional shape forming apparatus, in which the molding table 3 is sunk slightly below the liquid surface with respect to the photocurable resin liquid 2 stored in the liquid storage tank 1. When a thin layer of the resin liquid 2 formed between the upper surface of the molding table 3 and the liquid surface is irradiated with laser light or the like from above the liquid surface, a photocurable layer corresponding to the light irradiation pattern is formed. When the molding table 3 is gradually sunk deeply and the light irradiation as described above is alternately repeated, photocurable layers having a predetermined plane pattern are sequentially stacked to form a large number of photocurable layers. A molded product having a three-dimensional shape consisting of is obtained.

In the above method, the photocurable layers are sequentially stacked while being supported by the photocurable layer below. Like the pyramid structure, the outer shape of the photocurable layer stacked on top is
Always be the same size or smaller than the photocuring layer below,
The photo-curing layer can be stacked stably, but when the outer shape of the photo-curing layer stacked on top is larger than the photo-curing layer below, the stacking of the photo-curing layer becomes unstable and the photo-curing layer above There is a problem that the layer is deformed or the three-dimensional shape is broken. In particular, when the photo-curable resin is photo-cured, it may shrink or warp, and the photo-cured layer of the portion that greatly protrudes from the outer shape of the three-dimensional shape is likely to be warped or contracted as described above. .. Furthermore, when forming the photocurable layers by stacking, the stacked photocurable layers or molded products may be moved up and down in the liquid of the photocurable resin liquid. The photo-curable layer is likely to be deformed by the above.

Therefore, in the case of manufacturing a three-dimensional molded article having a complicated shape portion or an unstable shape portion, which requires a photocurable layer larger than the lower photocurable layer to be stacked above, A method is provided in which a support is provided on the base on which the photocurable layers are stacked, and the upper photocurable layer is supported by the support (Japanese Patent Laid-Open No. 2-52725), or on a wide lower photocurable layer,
At the same time as the formation of the photo-curing layer forming the three-dimensional shape, a supporting photo-curing layer is formed at a different position from the photo-curing layer forming the three-dimensional shape, and the supporting photo-curing layers are sequentially stacked. A method in which a vertical columnar reinforcing shape retaining portion is provided and the protruding portion of the upper photocurable layer is supported by this retaining portion (Japanese Patent Laid-Open No. 2203/1990).
No. 5) is proposed.

7 and 8 show a method for forming a three-dimensional shape using a photo-curing support layer. As shown in FIG. 7 (a), a three-dimensional molded article M having a main body b formed of a two-tiered rectangular parallelepiped and laterally extending portions a and a at the upper portion of the main body b is described above. The photo-curing layers are stacked and formed by the process. At this time, as shown in FIG. 7B, the overhanging portions a and the vertical columnar supporting portions S ₁ that support the a are formed in the same step as the photo-curing layer forming the three-dimensional shape. Further, the main body b of the molded product M is also formed on the lattice support-shaped support portion S ₂ formed of a photocurable layer. That is, as shown in FIG. 8, the main body b of the molded product M is formed on the upper surface of the molding table 3 via the lattice-shaped support portion S _2, and the overhanging portions a and a protruding from the main body b are formed. Of the columnar support S
_{With 1} , it will be supported by the molding table 3.

As a result, the tips of the overhanging portions a and a do not hang down or warp upward. It should be noted that the lattice-shaped support portion S _{2 that} supports the main body b facilitates the separation of the main body b from the surface of the molding table 3.

[0008]

However, according to the above-mentioned
According to the conventional technique, after the molded product M is molded,
There is a problem that it is difficult to take out the molded product M from the
It was To take out the molded product M from the molding table 3, the process shown in FIG.
So that each support S₁, S ₂The bottom edge of the
Between the molding tool 3 and the upper surface of the molding table 3
Insert the above separating tool H into the
Item M and each support S₁, S₂Peel off
remove. At this time, the molded product M is the lattice supporter S₂Through
If the separating tool H is formed on the molding table 3 as
Since it does not touch M directly, the molded product M is less likely to be damaged.
Yes. Also, the molded product M is in close contact with the molding table 3 over the entire surface.
In comparison with,₂Is the contact area with the molding table 3
Is less, so less force is required to separate it from the molding table 3.
You don't have to.

However, the photo-cured layer immediately after curing and the molded article M in which the photo-cured layers are stacked are not completely cured, and are in a relatively flexible and easily deformable state. Therefore, when a strong force or a biased force is applied when taking out the molded product M from the molding table 3, the molded product M is deformed. Even if an accurate three-dimensional shape can be formed by light irradiation, if the molded product M is deformed when taken out from the molding table 3, the final product shape accuracy will be greatly reduced. In particular, since the above-mentioned overhanging portions a, a, etc. are extremely easily deformed, it was extremely difficult to take out the molded product M without deforming it.

After the molded product M is placed on the molding table 3 and sent to a heating furnace, an ultraviolet irradiation device, etc., and finally cured, that is, after-cured, the photo-cured layer,
If the molded product M is separated from the molding table 3, it is possible to prevent the molded product M from being deformed. However, in this method, the molded product M
At the same time that the respective support portions S ₁ and S ₂ are completely hardened, they are strongly fixed at the contact surface with the molding table 3 and cannot be separated from the molding table 3 by the above-mentioned operation by the separating tool H. Will end up. In addition, if a shock is applied to the molded product M during the above separating operation, the molded product M may be chipped or cracked. Further, since the molding table 3 is also used in a post-process such as after-curing, the molding table 3 cannot be used for the work of forming the photocurable layer during that time, and there is a problem that the work efficiency deteriorates.

In order to solve such a problem, Japanese Patent Laid-Open No. 2-
In the method disclosed in No. 128829, a flexible sheet-shaped member is provided between the molding table and the molded product, and after removing the sheet-shaped member and the molded product from the molding table, the sheet is pressed from the lower surface of the molded product. The member is peeled off. In this method, the sheet-shaped member and the molding table can be easily separated. However, there is a drawback that the work of peeling off the sheet-shaped member from the molded product and the work of sticking the sheet-shaped member on the molding table for each molding operation are troublesome. In particular, if is supported overhanging portion a columnar support portion S ₁ as described above, only the columnar support part S ₁ rests a flexible sheet-like member, it is not fixed to the molding platform 3 Therefore, when the tip of the overhanging portion a warps upward, the columnar supporting portion S ₁ and the sheet-like member also warp upward, so that the overhanging portion a
The effect of preventing the deformation of is completely lost.

Therefore, an object of the present invention is to easily and efficiently take out the formed product in the above-described three-dimensional shape forming method, and at the time of this taking-out work, the formed product is deformed. It is an object of the present invention to provide a method for forming a three-dimensional shape that can favorably prevent damage and breakage.

[0013]

In the method for forming a three-dimensional shape according to the present invention for solving the above problems, a photocurable resin is irradiated with light to form a photocurable layer, and the photocurable layer is formed into a plurality of layers. In the method of stacking to form a three-dimensional shape, a photo-curing layer forming a three-dimensional shape is formed on a molding table via a supporting photo-curing layer, and the supporting photo-curing layer is formed on the upper surface of the molding table. The supporting convex portion is supported on the upper end of the projecting supporting convex portion, and the supporting convex portion can be supported with respect to the supporting photocurable layer without preventing the supporting photocurable layer from moving upward and destroying the supporting photocurable layer. Be prepared to remove it.

In the method of the present invention, basically, the same work steps, materials to be used, and equipment as in the method for forming a three-dimensional shape using a usual photocurable resin can be applied. Specifically, for example, a thin layer of the photocurable resin liquid is irradiated with light such as laser light according to a predetermined pattern, and a photocured layer having a constant thickness is formed in the portion irradiated with the light. A new photo-curable resin liquid is supplied on the photo-curable layer to form a thin layer of the photo-curable resin liquid, or the photo-curable layer is submerged in the resin liquid to form a thin resin liquid layer on the photo-curable layer. Then, light is irradiated in the same manner as described above to form a new photocurable layer on the photocurable layer. By repeating such steps, a plurality of photo-curing layers are sequentially stacked to manufacture a molded product having a desired three-dimensional shape.

According to the present invention, the photo-curable layer forming a three-dimensional shape is formed on a molding table which can be raised and lowered or fixed. The basic structure of the molding table is the same as in the case of a normal three-dimensional shape forming method and apparatus. In addition, a supporting photocurable layer is formed below the photocurable layer forming the three-dimensional shape. That is, on the molding table, first, after forming a supporting photocurable layer of a predetermined shape pattern and number of layers,
A photocurable layer forming a three-dimensional shape will be formed thereon. The shape pattern and the number of layers of the supporting photocurable layer are
It is arbitrarily set according to the shape of the three-dimensional molded product formed on it. The supporting photocurable layer may be formed so that the bottom surface portion of the molded product can be supported with a constant thickness, but when a part of the molded product has an overhanging portion that needs to be supported, The supporting photocurable layer is formed up to a position where the protruding portion can be supported. The stacking thickness or the number of layers of the supporting photo-curable layer is set so that the molded product can be supported reliably and that it can be supported by the supporting projections described later.

The supporting photo-curable layer is partially supported by the upper ends of the supporting projections at a plurality of positions projecting on the upper surface of the molding table. Therefore, the supporting photocurable layer, that is, the molded product is supported by the molding table only through the plurality of supporting convex portions. The supporting protrusions are arranged at a plurality of positions on the molding table in accordance with the shapes of the molded product and the supporting photocurable layer. The support convex part is detachably attached to the molding table,
If the mounting position is changeable, the mounting position of the supporting convex portion can be changed according to the arrangement shape of the molded product and the supporting photocurable layer.

The supporting photo-curable layer is formed near the upper end of the supporting convex portion. That is, at a position near the upper end of the support protrusion,
By irradiating the photocurable resin liquid with light to form the supporting photocurable layer, the supporting photocurable layer is formed with the upper end of the supporting convex portion embedded in the supporting photocurable layer. It The depth of embedding the supporting convex portion in the supporting photo-curable layer may be set to such an extent that the integral bonding property between the supporting convex portion and the supporting photo-curing layer is sufficient. The supporting protrusions may be embedded in a layer or a plurality of supporting photocurable layers.

The supporting convex portion is capable of preventing the supporting photo-curable layer from moving upward with respect to the supporting photo-curable layer, and can be removed without breaking the supporting photo-curable layer. That is, as described above, in the state in which the vicinity of the upper end of the supporting convex portion is embedded in the supporting photo-curable layer, even if the supporting photo-curing layer tries to move upward, the supporting convex portion prevents the movement, and When necessary, the supporting protrusions can be removed from the supporting photocurable layer without destroying the supporting photocurable layer.

As a supporting means therefor, for example, even if the upper end of the supporting convex portion is formed in a rod shape such as a column or a polygonal column, the upward movement of the supporting photocurable layer can be prevented to some extent. It is also possible to take out the supporting protrusions by pulling out the supporting protrusions below the supporting photo-curable layer. However, in order to surely and firmly prevent the upward movement of the supporting photocurable layer and to smoothly take out the supporting convex portion, the following structures are preferable.

That is, a male screw is cut on the upper end of the supporting convex portion. When the photocurable resin liquid is photocured around the male screw portion to form the supporting photocurable layer, a female screw is cut on the contact surface of the supporting photocurable layer with the male screw portion. In this state, the supporting photocurable layer is favorably supported on the supporting convex portion by the screw engagement with the supporting convex portion while surely preventing the movement in the vertical or horizontal direction. Then, when the male screw portion of the supporting convex portion is rotated with respect to the supporting photocurable layer, the male screw portion smoothly comes out from the female screw portion of the supporting photocurable layer, and the supporting photocurable layer is broken or a strong force is applied. The support protrusion can be removed without adding the.

In order to form a supporting photo-curable layer in close contact with the periphery of the male screw portion of the supporting convex portion, it is necessary to irradiate the valley portion of the male screw portion with light to photo-cur the resin liquid. For that purpose, the focal position of the laser beam is adjusted so that the irradiation light spreads diagonally below the liquid surface of the resin liquid and reaches the valley of the male screw part, or in the resin liquid. It is effective to make the light diffuse to some extent.

As another preferable supporting means, the upper end of the supporting convex portion is made of a heat-soluble material such as wax, and the supporting convex portion having the heat-soluble portion is mounted on a molding table by a bolt or the like. It is possible to adopt a method in which the auxiliary support plate is detachably attached so as to protrude from the upper surface. If the resin liquid is photo-cured around the heat-fusible portion to form the supporting photo-curable layer, the supporting function of the supporting photo-curable layer can be achieved by the supporting convex portion, as described above. Then, after the molded product is formed, if the auxiliary support plate is removed from the molding table and the molded product is subjected to aftercure with this holding support plate, the supporting photocurable layer is heated by heating with a heating lamp or the like during the aftercure. The embedded heat-fusible portion melts out, and the supporting convex portion comes off from the supporting photocurable layer. Therefore, the material of the heat-fusible part is preferably one having a melting temperature at which it is melted by heating in the aftercure. The shape of the heat-fusible part is one that has an enlarged part to prevent coming out, an inverse taper part, a dovetail joint structure, etc. Is preferable because it can be reliably prevented.

As the supporting means for the supporting photocurable layer by the supporting convex portion, in addition to the specific examples described above, if the above-mentioned action can be achieved, the usual supporting means for resin molding or machinery may be applied. You can

[0024]

The photocurable layer constituting the three-dimensional molded article is supported by the molding table via the supporting photocurable layer and the supporting convex portion, and the supporting convex portion is located above the supporting photocuring layer. As long as it is able to prevent movement, a three-dimensional shape consisting of a precise shape of the photocurable layer formed by light irradiation can be used without causing a part of the photocurable layer to sag or warp during the molding process. It can be made. In particular, by providing the supporting photocurable layer, even if a part of the molded product has an overhang or the like, it can be reliably supported so as not to be deformed.

If the supporting photocurable layer is formed directly on the surface of the molding table, as described above, when peeling the supporting photocurable layer from the surface of the molding table, an excessive force is applied to the molded product. In addition, there arises a problem that it is deformed or a part of the molded product is damaged. However, if the supporting photo-curable layer is supported by the molding table via the supporting protrusions, and this supporting table can be removed without destroying the supporting photo-curable layer,
The supporting photo-curable layer and the molded article thereon can be easily removed from the molding table without applying undue force to the molded article.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an implementation state of the method of the present invention, in which a photocurable resin liquid 10 stored in a liquid storage tank 1 is added to a horizontal plate-shaped molding table 2 which moves up and down in the liquid.
0 is sunk. An operating arm 22 extends above the liquid surface from the molding table 20, and the operating arm 22 is moved up and down by various operating mechanisms to immerse the molding table 20 in the photocurable resin liquid 10 to an arbitrary depth. The molding table 20 can be lifted above the liquid surface.

As shown in FIG. 2, a large number of support bolts 30 serving as support projections are screwed and attached to the molding table 20 from the lower surface side of the molding table 20.
The tip of the male screw portion 32 of the above-mentioned protrudes from the upper surface of the molding table 20. A three-dimensional shape is formed using the above-described molding device. When the molding table 20 is submerged near the liquid surface of the photocurable resin liquid 10, the liquid surface is irradiated with the laser beam 60 in a predetermined pattern. The thin layer is photo-cured to form a photo-curable layer 40 for forming a three-dimensional shape. At this time, the photocurable layer 4 is provided at a position different from the photocurable layer 40 for forming the three-dimensional shape.
A supporting photo-curable layer 42 for supporting 0 is also formed. If the molding table 20 is gradually submerged in the liquid and the pattern irradiation of the laser beam 60 is performed at each step, the molding table 2
0 and a plurality of photo-curing layers 40 and supporting photo-curing layer 4
2 are stacked to form a molded article M having a desired three-dimensional shape, a lattice support portion S ₁ and a columnar support portion S ₂ as shown in FIGS. 7 and 8. Become.

However, in this embodiment, as shown in FIG. 1, the position where the lowermost photocurable support layer 42 is formed is not on the surface of the molding table 20, but on the male screw portion 3 of the support bolt 30.
Set near the top of 2. Specifically, as shown in FIG. 4, when the upper end of the male screw portion 32 is arranged near the liquid surface and the laser beam 60 is irradiated, the resin liquid 1 is formed around the male screw portion 32.
0 is photocured to form a supporting photocurable layer 42 having a constant thickness. By appropriately setting the focal position and light intensity of the laser light 60, the resin liquid 10 can be photo-cured to a certain depth.

In order to surely form the supporting photo-curing layer 42 also in the valley portion of the male screw portion 32, the focus position of the laser light 60 is set to be slightly higher than the liquid surface. By doing so, the laser beam 60 spreads below the liquid surface, and therefore reaches the valley portion of the male screw portion 32 and the resin liquid 1 at that portion is reached.
0 can be photocured. The resin liquid 10 is
Since the light is hardened slightly outside the beam of the laser light 60, even if the laser light 60 does not completely irradiate the valley portion of the male screw portion 32, the supporting light hardening layer 42 that adheres to the entire periphery of the male screw portion 32 is formed. It is possible to form.

As shown in FIGS. 3 and 2, the male screw portion 3
2 is completely filled with a number of supporting photocurable layers 42, and then a photocurable layer 40 forming a three-dimensional shape is formed,
The tip of the male screw part 32 does not bite into the molded product M.
The supporting portion S _{2 in which the} male screw portion 32 is composed of the supporting photocurable layer 42
In the embedded state, so that the internal thread corresponding to the outer shape of the male thread portion 32 to the supporting photocurable layer 42 is off, so are engaged with each other, the flow resistance of the resin solution 10 to the support portion S ₂ Or even when shrinkage stress at the time of light curing is added,
The supporting portion S ₂ does not move in either the vertical direction or the horizontal direction.

When the photo-curable layer 40 forming a three-dimensional shape is formed up to the uppermost layer and the molded article M having a predetermined shape is molded,
The molded product M and the supporting portions S ₁ and S ₂ are removed from the molding table 20. For example, in FIG. 2 or FIG. 3, by rotating the support bolt 30, the external thread 32 is relatively screws rotated relative female thread of the support portion S _2, will get out of the support unit S _2. The supporting portions S ₂ , S ₁ and the molded product M on the supporting portions S ₂ and S ₁ after the male screw portion 32 has come out are separated from the molding table 20, and are sent to the next after-cure process or the like. Subsequent steps may be performed in the same manner as a normal three-dimensional shape forming method, and therefore description thereof is omitted. In addition, each support S
₁ and S ₂ may be cut or scraped from the molded product M at an appropriate time in the manufacturing process.

Next, the embodiment shown in FIG. 5 is different from the above embodiment in the structure of the supporting projections. In this embodiment, the auxiliary support plate 50 is mounted on the molding table 20 with mounting bolts 52. A plurality of screw shafts 34 are embedded in the upper surface of the auxiliary support plate 50. A heat-fusible member 36 such as wax is attached to the upper end of the screw shaft 34. The heat-fusible member 36 has a reverse tapered shape or a reverse truncated cone shape with a wide upper end and a narrow lower end.

Using the molding apparatus as described above, the molding table 20 is lowered stepwise and the laser beam 60 is irradiated in the same manner as in the above-described embodiment, so that the photocurable layer 40 and the supporting photocurable layer 42 are formed.
Are formed, and the supporting portions S ₁ and S ₂ and the molded product M are manufactured. The supporting photo-curable layer 42 of the supporting portion S ₂ is formed with the heat-soluble member 36 embedded therein. Since the heat-fusible member 36 has the inverse taper structure, the supporting photo-curable layer 42 is prevented from moving in both the vertical direction and the horizontal direction, and the heat-fusible member 36 is screwed from the heat-fusible member 36 to the auxiliary support plate. It is supported and fixed to the molding table 20 via 50.

After the molded product M is molded, the mounting bolt 52
Then, the auxiliary support plate 50 supporting the molded product M and the supporting portions S ₁ and S ₂ is separated from the molding table 20. The auxiliary support plate 50 is sent as it is to the after-cure process. The heat-soluble member 36 is melted by the heating in the after-cure process. Then, the supporting photo-curable layer 4 of the supporting portions S ₁ and S ₂
The fixing to 2 is released, and the molded product M and each support S
₁ and S ₂ are separated from the auxiliary support plate 50. Subsequent work steps are performed in the same manner as in a normal three-dimensional shape forming method.

[0035]

According to the method for forming a three-dimensional shape according to the present invention described above, the photocurable layer forming the three-dimensional shape is supported on the molding table via the supporting photocurable layer and the supporting projections. By doing so, it is possible to reliably prevent deformation of the photocurable layer, that is, the molded product during the molding operation, and obtain a molded product having a three-dimensional shape with excellent shape accuracy.

In particular, since the supporting means for supporting the photo-curable layer by the supporting projections can prevent the photo-curable layer for support from moving upward, the photo-curable layer can be prevented from being deformed upward due to warping or the like. As well as being able to remove the supporting photo-curing layer without destroying it, you can easily take out the molded product without applying excessive force to the molded product to deform or damage it. it can.

As a result, a molded product having a highly accurate three-dimensional shape can be manufactured extremely efficiently, which greatly improves the processing accuracy and work efficiency in this type of three-dimensional shape forming method. You can contribute.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the main part of the above.

FIG. 3 is an enlarged sectional view of part A in FIG.

FIG. 4 is a schematic cross-sectional view illustrating a photo-curing process.

FIG. 5 is a partially sectional front view showing another embodiment.

FIG. 6 is a perspective view showing a specific example of a three-dimensional shape forming apparatus.

FIG. 7 is a perspective view showing a specific example of a molded product and a supporting portion.

FIG. 8 is a front view showing a method for taking out a molded product in a conventional example.

[Explanation of symbols]

10 Photocurable Resin Liquid 20 Molding Table 30 Support Bolt 32 Male Thread Part (Supporting Convex Part) 40 Photocurable Layer Forming Three-Dimensional Shape 42 Photocurable Layer for Support 60 Laser Light M Molded Product S ₁ , S ₂ Support Part

Claims (1)

[Claims] 1. A method for forming a photocurable layer by irradiating a photocurable resin with light to form a photocurable layer, and stacking a plurality of the photocurable layers to form a three-dimensional shape. The support photo-curable layer is formed on the molding table via the supporting photo-curing layer, and the supporting photo-curing layer is supported on the upper ends of the supporting convex portions projecting on the upper surface of the molding table. The method for forming a three-dimensional shape, characterized in that the supporting photocurable layer can be prevented from moving upward and can be removed without destroying the supporting photocurable layer.