JPH0533901B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical modeling method for forming a solid body of a desired shape using light and a photocurable fluid material.

Conventional technology and its problems Conventionally, models corresponding to the product shape required during mold production, models for tracing control in cutting machining, or models for die-sinking electric discharge machining electrodes have been produced by hand processing or by using an NC milling machine. This was done by NC cutting using tools such as. However, when using manual machining, there is a problem in that it requires a lot of time and skill, and when using NC machining, it is necessary to create a complex machining program that takes into account replacement and wear to change the shape of the cutting edge. In addition, there is a problem in that additional finishing machining may be required to remove steps formed on the machined surface.

In order to solve these problems, the present inventor has proposed the following optical modeling method (Japanese Patent Application Laid-open Nos. 60-247515 and 62-101408).

In one embodiment of the method, a photocurable fluid material is housed in a container, and the depth is such that a continuous hardened portion extending over the upper and lower surfaces of the fluid material is obtained by irradiating light from above the container, and selectively irradiate light through a light converging device such as a convex lens to form a hardened portion extending over the upper and lower surfaces of the fluid material, and further to form a depth corresponding to the above-mentioned depth on the hardened portion;
A photocurable fluid material is added, and the fluid material is selectively irradiated with light to form a cured portion that extends continuously upward from the cured portion, and the addition of the photocurable fluid material and the cured material are performed. A solid having a desired shape is formed by repeating addition and formation of a hardened portion.

The photocurable fluid material can be added by lowering the base plate 52 supported by a support rod 51 into the fluid material A as shown in FIG. 9, and as shown in FIG. , a liquid-tight box-shaped bottomed body 6 having a bottom wall 62 having optical transparency.
It can also be carried out by raising 1 in fluid material A. Hardened part a and the first part shown in FIG.
The hardened portions b shown in Figure 0 are in the process of forming a solid having the desired shape after repeated stepwise curing. In this solid formation process, the occurrence of various deformations described below becomes a problem.

Generally, the photocurable fluid material A has shrinkage properties during curing, and by repeating stepwise curing, differences in the amount of shrinkage between the cured portions accumulate. Therefore, in the method of adding a fluid substance shown in FIG. 9, when forming the tongue a' on the hardened portion a, the tongue
There was a problem that deformation occurred at the a′ end due to the difference in the amount of shrinkage.

On the other hand, in the method of adding a fluid substance shown in FIG. 10, the bottomed body 61 is once raised above the depth at which the continuous hardened portion b is obtained, the adhesion between the bottom wall 62 and the hardened portion b is peeled off, and then The bottomed body 61 is lowered to set the distance between the lower surface of the bottom wall 62 and the upper surface of the hardened portion b to a distance corresponding to the depth.
There was a problem in that the tongue piece b' was plastically deformed along with the bottom wall 62 of the bottomed body when it was peeled off.

Furthermore, when solid formation is carried out to obtain a solid 41 having a shape as shown in FIG. 11a in which the base surfaces of two truncated square pyramids are joined,
As shown in the figure, the solid body 42 whose four circumferential side walls are curved and deformed due to the difference in the amount of shrinkage, and the solid body 43 with the rectangular roof protruding as shown in figure 12a, are formed as shown in figure 12b. As shown in FIG. 2, there was a problem in that the peripheral edge of the roof portion 44' became a solid body 44 that warped upward.

In another embodiment of the above-mentioned optical modeling method, a container containing a fluid material A and a light guide that guides light emitted from a light source device into the fluid material A of the container are moved relatively to form a desired shape. A modeling method for forming a solid, and a method of converging the light emitted from two light sources into a point shape, making the respective concentrated light energy irradiation points intersect with each other in the fluid material A, and moving the intersection points. Although there are modeling methods for forming the above-mentioned solid, these methods also have the problem that deformations similar to those shown in FIGS. 9, 11b, and 12b occur.

An object of the present invention is to solve the above-mentioned problems and provide an optical modeling method that can prevent deformation from occurring during the formation of a hardened portion by light irradiation.

Means for Solving the Problems The above object of the present invention is to house a photocurable fluid material that is cured by light in a container, and while irradiating the fluid material with light, place the light irradiation area on the container. When forming a solid in the desired shape by moving it relative to the shape of the object in the horizontal and vertical directions, it adheres to the parts of the object where deformation is likely to occur in order to prevent deformation of the hardened portion during the formation process. Alternatively, the solid formation is performed while simultaneously hardening and forming a reinforcing shape-retaining part that extends between the part and other parts of the molded object, and after the formation, the shape-retaining part is removed as necessary. This is achieved by an optical modeling method characterized by the following.

As the photocurable fluid substance, various substances that are cured by light irradiation can be used, such as modified polyurethane methacrylate, oligoester acrylate, urethane acrylate, epoxy acrylate, photosensitive polyimide, and amino alkyd.

The photocurable fluid substance may be mixed with a modifying material such as pigment, ceramic powder, metal powder, etc. in advance.

As the light, various types of light such as visible light and ultraviolet light can be used depending on the photocurable material used. Although the light may be ordinary light, using laser light has the advantages of increasing the energy level, shortening the modeling time, and improving the modeling accuracy by utilizing good light focusing. can.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

Figure 1 shows the target U-shaped solid 1 in side view.
shows. Regarding the method of forming this solid 1, Fig. 3 shows the following:
A method using a support rod 51 and a base plate 52 (shown in FIG. 9), FIG.
1 (shown in Figure 10),
Each shows one embodiment in which the present invention is applied.

First, the method of the present invention shown in FIG. 3 will be explained.
First, the base portion 2 of the solid body 1 is formed on the base plate 52 by repeating the lowering of the base plate 52 in the photocurable fluid material A and the formation of a cured portion based on selective light irradiation via the light concentrator 6 as described above. After forming the base 2, a side wall 3 extending upward from one end of the base 2 is formed, and then an upper wall 4 is formed on the side wall 3. During the stepwise hardening process, A thin tongue piece 4' corresponding to the lower end of the upper wall part 4 is formed. The tongue piece 4' is the ninth
As shown in the figure, the solid 1 is most likely to deform during the stepwise hardening process. Therefore, in the case of forming a solid body with such a shape, a reinforcing shape-retaining portion 5 extending between the tongue piece 4', which is likely to be deformed, and the vicinity of the other end of the base 2 is provided, and the holding portion 5 is formed at the same time as the side wall portion 3 is hardened and formed, and after forming the side wall portion 3 and the shape retaining portion 5, the upper side portion 4 continuous to the upper ends thereof is hardened and formed. Therefore,
When the tongue piece 4' is formed, the shape retaining part 5 extending from the base 2 reinforces and supports the tongue piece 4' and prevents deformation of the tongue piece 4', so that the upper side part 4 can be formed without deformation. The solid 7 thus formed (second
By removing the shape-retaining portion 5 from the solid material (see figure) by an appropriate method such as cutting, it is possible to obtain a solid body 1 having a desired shape without deformation.

In addition, when adding the fluid substance A onto the cured portion after once forming a cured portion based on light irradiation, it is actually desirable to perform the following operation. As shown in FIG. 7a, when the base plate 52 is lowered to a depth that provides a continuous hardened portion on the hardened portion and the fluid substance A is caused to flow onto the hardened portion, the descending distance of the base plate 52 is extremely long. Since the amount of the fluid is small, as shown in FIG. 7b, the surface tension of the fluid material A may prevent the fluid material A from flowing onto the hardened portion, and the above-mentioned addition is always not reliable, and furthermore, it is not necessary to manually apply the fluid material A. It is necessary to introduce the fluid substance A onto the hardened portion, which requires time and effort. In contrast, as shown in FIG. 8, the base plate 52 is lowered below the above depth to allow the fluid material A to flow onto the hardened portion, and then the base plate 52 is raised to separate the upper surface of the fluid material A and the upper surface of the hardened portion. If the distance is the distance corresponding to the above depth, then the fluid material A
can be added reliably, and does not require manual introduction of the fluid substance.

Next, the method of the present invention shown in FIG. 4 will be explained.
In this method, as shown in FIG.
A solid having a desired shape is formed by repeating the rising of No. 1 in the fluid material A and the formation of a hardened portion based on selective light irradiation passing through the bottom wall 62. This method also involves forming the base 2 and then hardening the side portions 3 in the same manner as described in FIG.
At the same time, a shape-retaining portion 5 extending from the base 2 to the tongue 4' which may be deformed is hardened and formed, and an upper side portion 4 is formed on the side portion 3 and the shape-retaining portion 5 as shown in FIG. A solid 7 with a shape-retaining portion is obtained, and the shape-retaining portion 5 is removed from the solid 7 to obtain a desired-shaped solid 1 without the above-mentioned deformation. Even with this method, the tongue piece 4', which is likely to be deformed, is
The solid body 1 is reinforced and supported by the shape retaining portion 5, and thus has a desired shape without deformation.

Next, to explain the case of forming the solid 41 shown in FIG. 11a, when obtaining the outer shape of the solid 41 based on the optical modeling method shown in FIG. 3 or 4, as shown in FIG. In addition, if the reinforcing shape retaining portions 32 that vertically connect the opposing side walls 31 are formed at the same time while hardening the side walls 31, the side walls 31, which are prone to curve deformation, can support each other via the shape retaining portions 32. As a result, the occurrence of the curved deformation is prevented, and the solid body 33 with the shape-retaining portion 32 having an accurate outer shape can be obtained. In addition, in order to obtain the solid body 43 having a rectangular roof overhang shape as shown in FIG. 12a, as shown in FIGS. A shape-retaining base 36 extending outward from the lower end and a reinforcing shape-retaining portion 38 extending upward from the periphery of the base 36 and continuing to the periphery 37' where there is a risk of deformation of the roof 37 are formed by hardening, and then A roof portion 37 is formed. As a result, the peripheral edge part 37', which is likely to be deformed, is reinforced and held by the shape retaining part 38 extending from the shape retaining base 36, and the peripheral edge part 37' as shown in FIG. 12b is
The occurrence of deformation is prevented, and the solid 39 shown in FIGS. 6a and 6b can be obtained. After obtaining the solid 39, by removing the shape retaining portion 38 and the shape retaining base 36 from the solid 39, a solid 43 having a desired shape can be obtained.

As described above, the method of the present invention is capable of simultaneously hardening and forming a reinforcing shape-retaining portion that is attached to a location where deformation is likely to occur or that extends between the location and other locations, and at the same time forming a solid material having a desired shape. It is characterized by performing formation, and as long as it has this feature, it can be applied to various modeling methods based on light irradiation. Therefore, in addition to the modeling method based on light irradiation described in the above embodiments, for example, a method in which the upper surface of a photocurable fluid material in a container is slightly raised and a solid is formed by light irradiation from above, A part of the bottom wall is a transparent plate, a base surface for supporting the cured portion is placed facing the transparent plate, and a solid is applied to the base surface based on light irradiation through the transparent plate while keeping the base surface away from the transparent plate. It can be applied to a method of forming the same. In addition, light irradiation in these methods includes, for example, light irradiation using a light guide, light irradiation in which light emitted from multiple light sources intersects at one point, and light irradiation in which the portion of high light intensity in a cross section perpendicular to the optical axis is annular. It is possible to employ methods such as irradiation of light that exhibits a distribution. When using the above-mentioned light guide, if the tip of the light guide is hemispherical, there is an advantage that the light can be converged and irradiated so that the light energy is concentrated in a point shape. Further, by employing light irradiation in which the plurality of lights intersect, the light energy can be nonlinearly increased at the intersection of the lights, and a solid having a desired shape can be quickly formed. By irradiating the light having the above-mentioned annular light intensity distribution, a relatively thick band-shaped solid can be formed with high dimensional accuracy by one scan of the light irradiation, and solids having a desired shape can be formed efficiently. .

Effects of the Invention As is clear from the above, according to the method of the present invention, when forming a solid of a desired shape by relatively moving the irradiation area of concentrated light energy with respect to a photocurable fluid material, in the forming process, The solid formation is performed while simultaneously hardening and forming a reinforcing shape-retaining part that is attached to a part of the object where there is a risk of deformation or that extends between the part and other parts of the molded object, and after the formation, the solid part is formed. Since the shape-retaining portion is removed as necessary, it is possible to provide an optical modeling method based on the shape-retaining portion that can reliably prevent the occurrence of deformation peculiar to the formation of a cured portion by light irradiation.

[Brief explanation of the drawing]

Figure 1 shows one of the solids formed according to the method of the present invention.
FIG. 2 is a perspective view showing an example of a solid with a shape-retaining part, FIG. 3 is an explanatory diagram schematically showing an embodiment of the method of the present invention, and FIG. An explanatory diagram schematically showing another embodiment, FIG. 5 is a perspective view showing a solid body with a shape-retaining portion obtained based on the method of the present invention, and FIG. 6a is a shape-retaining base and a shape-retaining portion obtained based on the method of the present invention. A perspective view showing a solid with parts, Figure 6b is a vertical front view thereof, Figures 7a and b
is an explanatory diagram showing a conventional method of adding a photocurable fluid material using a support rod and a base plate, FIG. 8 is an explanatory diagram showing a method for reliably adding the fluid material, and FIG. An explanatory diagram schematically showing one example of a modeling method, FIG. 10 is an explanatory diagram schematically showing another example of a conventional optical modeling method, and FIG. 11a shows a solid to be obtained based on the conventional method. 11b is a perspective view showing a solid formed based on the conventional method, FIG. 12a is a perspective view showing another solid to be obtained based on the conventional method, and FIG. 12b is a perspective view showing a solid formed based on the conventional method. FIG. DESCRIPTION OF SYMBOLS 1... Solid with desired shape, 4'... Lower part of upper piece (tongue piece), 5, 32, 38... Shape retaining part, 6... Light converging device, A... Photocurable fluid material.

Claims (1)

[Claims] 1. A photocurable fluid material that is hardened by light is placed in a container, and while irradiating light into the fluid material,
When the light irradiation point is moved horizontally and vertically relative to the container according to the shape of the object to be modeled to form a solid of the desired shape, in order to prevent deformation of the hardened portion during the formation process, The solid formation is performed while simultaneously hardening and forming a reinforcing shape-retaining part that is attached to a part where deformation is likely to occur or extends between the part and other parts of the modeled object, and after the formation, the shape-retaining part is formed. An optical modeling method characterized by removing parts as necessary.