JPS6340650B2 - - Google Patents

Description

[Detailed description of the invention]

FIELD OF THE INVENTION The present invention relates to an optical modeling method 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 complicated 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 this problem, a method has been proposed in which a thin photocurable resin layer is selectively and repeatedly irradiated with light by masking to obtain a desired three-dimensional shape. First, when light is irradiated onto a very shallow photocurable resin from above or below, a masking film with a light-transmitting part corresponding to the horizontal cross-sectional shape of the three-dimensional object to be obtained is placed in front of the photocurable resin. This irradiation obtains a thin-layer cured part with the desired cross-sectional shape, and for the continuous horizontal cross-sectional shape, the depth of the photocurable resin is increased little by little, the masking film is sequentially replaced, and the light irradiation is repeated. , to obtain the desired solid. However, this method has the following difficulties. (i) It is necessary to produce a masking film for each horizontal cross-sectional shape of the three-dimensional object to be obtained, which requires time and effort. In particular, in order to obtain a smooth curved surface, it is necessary to increase the number of solid divisions.
As a result, a large number of masking films are required, which increases production time and costs. (ii) In order to obtain a three-dimensional object with high dimensional accuracy, it is necessary to irradiate parallel light that accurately reflects the masking shape.
A restriction arises in that the type of light used is limited. (iii) Since irradiation is performed with parallel light, the curing of the resin can be controlled in the horizontal direction by masking, but in the vertical direction, it must be left to the absorption of light energy by the resin, that is, the depth at which the light energy reaches. This results in a disadvantage in terms of accuracy. (iv) Since part of the irradiated light is blocked by masking,
Light usage efficiency is low. (v) Since the entire horizontal section of the target shape is irradiated with light and cured at the same time, shrinkage distortion occurs all at once,
There is a risk of cracking or deformation. The present invention solves the problems of these conventional techniques,
Not only can you easily and accurately produce models for mold making, copying machining, and die-sinking electrical discharge machining, even if they have complex shapes, without having to change tools such as blades, It is an object of the present invention to provide a modeling method that can be applied to the production of various other shaped objects and requires less time and cost for production. Means for Solving the Problems The object of the present invention is to house a photocurable fluid material that is cured by light in a container, and to concentrate light energy in a point shape with an energy level necessary for curing the material. By an optical modeling method, the light energy concentration point is moved relative to the container in horizontal and vertical directions according to the shape of the object to be modeled, while irradiating light so as to obtain a solid having a desired shape. achieved. In order to irradiate the photocurable material with concentrated light in a point-like manner at an energy level necessary for curing, a light guide having a substantially hemispherical light emitting end is provided in the photocurable fluid material. By inserting the container and irradiating light through the light guide, a concentrated area of light energy can be obtained in front of the light emitting end, and while the container and the light emitting end are relatively moved, the light guide A solid having a desired shape can be obtained by irradiating light from a light body. The light guide may be a fiber or rod made of crystal, glass or synthetic resin. When using ultraviolet light, it is preferable to use quartz. The formation of the solid in the desired shape is achieved by placing the photocurable fluid material in a container at a depth that allows a continuous hardened portion covering the upper and lower surfaces of the material to be obtained by irradiating light from above; By irradiating light from above the substance through an optical lens, a point where light energy is concentrated is located in the substance to form a cured portion extending over the upper and lower surfaces of the substance, and the photocurable substance is further cured. The photocurable material is applied to the part to a depth corresponding to the depth, and the concentrated part of the light energy is moved from above the photocurable material to the added depth part of the material to remove the light from the cured part. This can be achieved by forming a continuously extending cured portion and repeating the addition of the photocurable substance and the formation of the cured portion. Formation of a solid through such repetition can be achieved, for example, by immersing a hollow or solid bottomed body that is translucent in the vertical direction into the photocurable fluid material in a container, so that the bottom surface of the bottomed body is immersed. and the upper surface of the bottom of the container, the material is stored at a depth such that a continuous hardened portion extending over the upper and lower surfaces of the material is obtained by light irradiation from above (for example, laser light irradiation), By irradiating light from above the body through an optical lens, a concentrated point of light energy is located in the substance to form a hardened portion that extends to the upper and lower surfaces of the substance between the bottom and top surfaces, and then the bottomed By slightly pulling up the body, the substance is added around the bottomed body so that a depth corresponding to the depth is formed between the upper surface of the hardened part and the bottom surface of the bottomed body, and The concentration point of the light energy is moved from above to the part to which the substance has been added to form a cured part that extends continuously from the cured part, and the addition of the photocurable substance and the formation of the cured part are repeated to obtain the desired effect. This can be done by forming a shaped solid. 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. 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. In order to perform concentrated light irradiation in a point-like manner with an energy level necessary for curing the photocurable fluid material, it is also necessary to use a wavelength equal to twice the wavelength suitable for curing the photocurable fluid material. irradiating two or more light beams having the same phase and intersecting each other in the photocurable material in a dotted manner, and absorbing two photons at the crossing point, which is necessary for curing the photocurable material. A desired level of light energy can be obtained, and by moving the point where the light beams intersect, a solid of a desired shape can be obtained. The phase-aligned light beam can be obtained by, for example, a laser beam. Alternatively, the photocurable fluid substance may be mixed with a modifying material such as pigment, ceramic powder, metal powder, etc. in advance. Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows one of the apparatuses for carrying out the method of the present invention.
An example is shown. The device includes a photocurable fluid material 4
A container 1 containing a container 1, a light source device 2, a light guide 3 that guides light emitted from the light source device to a photocurable material 4 in the container 1, and a container 1 and a light guide 3 are moved relatively. and a position control device 5. The container 1 can be of any suitable size and shape that can accommodate the shaped object to be obtained. The light source device 2 and the light guide 3 are fixed outside the container 1. The light guide 3 is a quartz fiber, and both ends are melted by an oxyhydrogen flame to form a radial shape in order to improve the efficiency of light incidence and to focus the light into a point shape when emitted. The position control device 5 supports the container 1 and is configured to control and move the container 1 in horizontal and vertical directions. This control can be performed as appropriate, such as automatic control such as NC, control by acquisition, or constant speed control. To perform modeling using this device, first the container 1
Put an appropriate amount of photocurable substance 4 into the container, and place the light source device 2 with the tip 3a of the light guide 3 close to the bottom of the container 1.
emit light from. Since the light is concentrated in a point in front of the output end, by adjusting the intensity of the incident light, the material 4 can be cured only at the point where the light is concentrated. In this state, the container 1 is moved by the position control device 5 to form a hardened portion in contact with the bottom surface of the container 1. Subsequently, after lowering the container 1 slightly or while lowering it gradually, it is moved in the horizontal direction to form a hardened part that is continuous with the hardened part. In this way, by appropriately moving the container 1 and continuously forming the hardened portion, it is possible to obtain the solid 6 in the desired shape. Also, depending on the shape of the object to be obtained, as shown in Fig. 1, an appropriate stand 7 may be placed inside the container 1, and the object may be shaped from the stand 7 separately from the bottom of the container. The two cured portions may be made to be continuous. The position control device only needs to be able to move the container 1 and the light guide 3 relatively horizontally and vertically. 1. The light guide 3 can be arbitrarily configured to be moved either horizontally or vertically. Next, another embodiment of the method of the present invention will be described with reference to FIG. First, as shown in FIG. 2a, a photocurable fluid material 4 is placed in a container 1 to an appropriate depth.
As shown in FIG. 2b, light is irradiated from above the substance 4 through an optical lens 20, thereby concentrating the light in the substance 4. In this state, the light concentration point is moved relative to the container, and light is selectively irradiated in accordance with the shape of the object to be obtained. At this time, the depth of the substance 4 is set to such a depth that a continuous hardened portion 60 extending over the upper and lower surfaces of the substance 4 is obtained by the light irradiation. If the depth is greater than this, the hardened portion formed loosely from the bottom of the container 1 will settle, making it impossible to obtain an accurate shaped object. Next, as shown in FIG. 2c, a photocurable material 4 is further added, and as shown in FIG. 2d, light is selectively irradiated from above the material 4. At this time, the substance 4 is added onto the hardened portion 60 to the same depth as described above. Further, the light irradiation is performed so that the newly formed hardened portion 61 is continuous with the previously formed hardened portion 60. Furthermore, by repeating the addition of the photocurable substance 4 and the formation of a cured portion by light irradiation,
Solids of desired shapes can be formed. Of course, a plurality of light source devices may be used, and light irradiation may be performed using a light guide such as a light fiber. Alternatively, light irradiation can be performed by a position control device that relatively moves the light source device and the container, as in the previous example. FIG. 3 shows still another example of the method of the present invention. In this example, two laser beams 8a and 8b are applied to the photocurable fluid material 4 from the light source devices 2a and 2b.
are irradiated in the substance 4 so as to cross each other. The wavelengths of the irradiated laser beams are the same and twice the wavelength suitable for curing the substance 4. In this way, when light beams with good optical coherence and the same phase, such as laser beams, are crossed and their wavelengths are made equal, the light energy increases nonlinearly at the crossing point, resulting in the so-called 2
High energy can be obtained by photon absorption. Therefore, by adjusting the intensity of each laser beam appropriately, the substance 4 can be cured at the intersection point 80 of the laser beams 8a, 8b by the intersection point 80 of the laser beams 8a, 8b. By relatively moving the light source devices 2a, 2b and the container 1 using a position control device such as the one described above, a solid body having a desired shape can be formed. Preferably, the container 1 is transparent so that light can be irradiated through the walls of the container. Furthermore, in order to obtain greater light energy at the optical fork, it is advantageous to increase the number of light beams. Note that the following example can be cited as a modification of the example shown in FIG. First, as shown in FIG. 4a, a box-shaped bottomed body 9 having a liquid-tight bottom wall and side walls is immersed in the photocurable fluid material 4 in the container 1.
The photocurable fluid material 4 is accommodated at a certain depth between the bottom surface 90 of the bottomed body 9 and the top surface 10 of the bottom of the container. As described above, this depth is such that a continuous hardened portion covering the upper and lower surfaces of the material 4 can be obtained by irradiating light from above. In this state, as shown in FIG. 4b, the optical lens 20 is inserted from above the bottomed body 9.
By irradiating light through the substance 4, the light is concentrated in the substance 4 and selectively irradiated, and the hardened portion 6
Get 0. Therefore, the bottom wall of the bottomed body 9 is made transparent to the irradiation light. Next, as shown in FIG. 4c, the bottomed body 9 is pulled up slightly. As a result, the substance 4 around the bottomed body 9 flows into the bottom of the bottomed body 9 and is added thereto. The lifting amount is
The depth of the substance 4 added between the upper surface of the already existing hardened portion 60 and the bottom surface 90 of the bottomed body is determined to be the same depth as described above. Also, in order to maintain a constant distance between the lens 20 constituting the light source and the bottom surface 90 of the bottomed body. The light source device 2 is raised by the same distance as the bottomed body 9. Thereafter, as shown in FIG. 4d, light is selectively irradiated by condensing light as described above so as to obtain a cured portion 61 continuous to the cured portion 60 from above the bottomed body 4. Furthermore, by repeating the addition of the photocurable substance 4 below the bottom surface 90 by pulling up the bottomed body 9 and the formation of a cured portion by light irradiation, a solid having a desired shape can be obtained.
In this example, the bottomed body 9 and the light source device 2 are raised, but it goes without saying that the container 1 may be lowered instead. In any case, changes in these relative positions can be controlled by a suitable positioning mechanism. According to the example shown in FIG. 4, the liquid surface of the photocurable material 4 to be cured is covered by the bottom surface 90 of the bottomed body, so that
This has the advantage of preventing the influence of the atmosphere inside the container, such as components in the air and dust. Experimental examples of the method of the present invention are shown below. Experimental example 1 A helium-cadmium laser beam with a wavelength of 3250 Å emitted from a light source with an output of 20 mW is focused at a focal length of 20 mm.
The light was focused using a quartz lens, and a cylinder with a diameter of 11 mm, height of 14 mm, and thickness of 0.2 mm was formed based on the method shown in Figure 2. In this case, while the container containing the photocurable material is circulated at a constant velocity around the vertical axis,
A cylinder with good accuracy was obtained by a simple operation of vertically raising the light source device. Note that Table 1 shows the photocurable materials used and the time required for modeling.

[Table] Experimental Example 2 The same light source as in Experimental Example 1 was used, and a quartz fiber manufactured by Fujikura Electric Wire Co., Ltd. with a diameter of 0.125 mm was used as the light guide.
A cylinder having the same dimensions and shape as Experimental Example 1 was manufactured using SM100-SY. The quartz fiber used had both ends melted using an oxyhydrogen flame to form a hemispherical shape with a diameter of about 0.2 mm. This allows the container containing the photocurable material to be rotated around the vertical axis.
A cylinder with good accuracy was obtained by a simple operation of vertically raising the tip of the light guide. The photocurable material used was the same as in Example 1, and the time required for modeling was also approximately the same. Effects of the Invention As is clear from the above, according to the present invention, the photocurable fluid material is
By irradiating light so that the light energy necessary for curing is concentrated in a point shape and moving the concentrated point relative to the container containing the substance, a solid with a desired shape can be formed. Even if it has a similar shape, it can be easily manufactured without considering tool replacement or wear, and even members with complicated internal hole structures can be manufactured in a single process. Therefore, the program can be simplified when manufacturing is automated by numerical control or the like. In particular, in the present invention, since the irradiation light is concentrated in a dotted manner, high energy can be obtained at the concentrated point, making it possible to speed up curing. Further, since the curing is performed at the concentrated areas, it is possible to accurately control the curing area not only in the horizontal direction but also in the vertical direction, resulting in good modeling accuracy. Therefore, there is no need for a masking film as in the conventional example described above, and the time and cost required for modeling can be reduced. Moreover, since there is no light blocking due to masking, the efficiency of light utilization is high. In addition, since the reaction always occurs at one narrow point, even if the photocurable material shrinks during curing, the volume loss due to shrinkage is compensated for by the supply of surrounding uncured material, thus curing a wide area at the same time. There are no problems such as hardening distortion or cracking as in the case of hardening. As can be understood from the above description, the method of the present invention can be applied not only to the production of molds, copying machining, and die-sinking electrical discharge machining electrode models, but also to the production of various other shaped products. It is. Furthermore, by dispersing pigments, metal powders, ceramic powders, etc. in photocurable materials and modeling them, it is possible to manufacture products with various characteristics such as decorative effects, conductivity, and wear resistance. . In this case, the shaped object can be used not only as a model or a matrix, but also for various purposes.

[Brief explanation of the drawing]

The figures are for explaining embodiments of the invention.
Fig. 1 is a longitudinal sectional front view schematically showing a device for carrying out one example, Fig. 2 is an explanatory diagram sequentially showing the implementation status of another example, and Fig. 3 is a diagram for carrying out still another example. FIG. 4 is a longitudinal sectional front view schematically showing an apparatus for the purpose of the present invention, and FIG. 4 is an explanatory diagram sequentially showing the implementation status of another example. 1... Container, 2... Light source device, 3... Light guide,
4... Photocurable fluid substance, 6... Solid with desired shape, 9... Bottomed body, 60, 61... Cured portion, 9
0...bottom surface of a bottomed body.

Claims (1)

[Scope of Claims] 1. A photocurable fluid material that is cured by light is placed in a container, and light is irradiated so that the light energy is concentrated in a dot shape with an energy level necessary for curing the material. , an optical modeling method characterized in that a solid body having a desired shape is obtained by moving the light energy concentration point relative to the container in horizontal and vertical directions according to the shape of the object to be modeled. 2. A light guide whose light emitting end is substantially hemispherical is inserted into the photocurable fluid material, and light is irradiated through the light guide to form a concentration point of light energy in front of the emitting end. 2. The optical modeling method according to claim 1, wherein the output end is moved relative to the container. 3. The photocurable fluid material is placed in a container at a depth such that a continuous hardened portion covering the upper and lower surfaces of the material is obtained by irradiating light from above, and the photocurable material is irradiated with light from above through an optical lens. By irradiating the light with light, a point where light energy is concentrated is located in the material to form a hardened portion extending over the upper and lower surfaces of the material, and the photocurable material is further applied to the hardened portion to a depth corresponding to the depth. The photocurable material is applied to a depth such that the light energy is concentrated from above the photocurable material to the added depth portion of the material to form a cured portion that extends continuously from the cured portion. 2. The optical modeling method according to claim 1, wherein a solid having a desired shape is formed by repeating the addition of the photocurable substance and the formation of the cured portion. 4. By immersing a hollow or solid bottomed body having translucency in the vertical direction into the photocurable fluid material in the container, a gap is formed between the bottom surface of the bottomed body and the upper surface of the container bottom, The substance is housed at a depth such that a continuous hardened portion extending over the upper and lower surfaces of the substance is obtained by irradiating light from above, and light is irradiated from above the bottomed body through an optical lens to generate optical energy. by locating a concentrated point in the substance to form a hardened part extending over the upper and lower surfaces of the substance between the bottom and top surfaces, and then by slightly pulling up the bottomed body, the upper surface of the hardened part and the bottom face of the bottomed body are separated. During the process, the substance is added around the bottomed body to a depth corresponding to the depth, and the light energy is concentrated from above the bottomed body to the added part of the substance. The method of claim 1 is characterized in that a cured portion is formed that extends continuously from the cured portion by moving the photocurable material, and the addition of the photocurable substance and the formation of the cured portion are repeated to form a solid having a desired shape. The optical modeling method described in Section 3. 5. Two or more beams of light having equal wavelengths twice as long as the wavelength suitable for curing the photocurable fluid material and having the same phase are arranged so as to intersect each other in a dotted manner in the photocurable material. By irradiating and obtaining a level of light energy necessary for curing the photocurable material through two-photon absorption at the intersection point, and moving the intersection point of the light beam relative to the container, the photocurable material is cured. Claim 1, characterized in that the light energy necessary for curing is selectively supplied.
Optical modeling method described in section. 6. According to any one of claims 1 to 5, wherein the photocurable fluid substance is mixed with a modifying material such as a pigment, ceramic powder, or metal powder in advance. The optical lithography method described.