Model supporting method and model molding apparatus

The present invention relates to a model support method and structure by model support means (support and / or gantry) in stereolithography.

Conventionally, by irradiating a photocurable resin in a liquid state with light to form a planar cured layer above the table, the relative positional relationship between the table and the light irradiation position is shifted in order, and the cured layers are stacked and formed. , A method of stereolithography of a three-dimensional shaped object (model) is known. In this conventional stereolithography, a model supporting means is usually stereolithographically formed between the model and the table. The model supporting means is a support that supports at least a part of the cured layer from the lower side in order to prevent the cured layer that is not supported by the lower cured portion from hanging down, which protrudes greatly from the lower cured portion of the cured layer constituting the model. The model and the model support means are provided as a gantry for forming the model and the support upwardly separated from the table so that the model and the model support means can be easily cut and separated from the table. The model support means is formed integrally with the model during modeling of the model. For example, as disclosed in Japanese Patent Application Laid-Open No. 6-8342 and as shown in FIGS. 5 to 7, the conventional model supporting means 1 is a cross section surrounded by a closed wall 2 in the horizontal direction. It has a plurality of cells 3 (small chambers) having a surface and extending in the vertical direction. The upper end of the wall around each cell 3 of the model supporting means 1 is integrally connected to the bottom surface 5 of the model 4 by the total length in the peripheral direction of each cell. After the stereolithography is completed, the model and the model supporting means are cut at the pedestal and removed from the table, and the model supporting means is separated and removed from the model.

<p> However, the method of supporting a model by the model supporting means in the conventional stereolithography has the following problems. When the model and the model supporting means are removed from the table as a unit after the optical modeling is completed, each cell of the model supporting means is supported by the cell wall around the horizontal direction, and the model supporting means is separated and removed from the model. At that time, there is a problem that the wall of the model supporting means remains on the bottom surface of the model. An object of the present invention is to solve such a conventional problem.</p>

<p> In order to solve the above problems, in the model modeling method of the present invention, in the process of modeling a model from a liquid resin, the wall of the model supporting means does not remain or remains on the bottom surface of the model after the model and the model supporting means are separated. There is a step of reducing the area of the connecting portion between the upper end of each wall in the vertical direction and the model, which constitutes the model supporting means, so that the amount of the model is small. With this configuration, the model modeling method of the present invention can realize a method in which the model supporting means can be easily separated from the model.</p><p> Further, in order to solve the above problems, in the model modeling method of the present invention, the connecting portions are arranged in a perforated pattern. With this configuration, the model modeling method of the present invention can support a stable model, and can easily distinguish between the model and the model supporting means, so that the model can be easily separated.</p><p> Further, in order to solve the above problems, the model modeling apparatus of the present invention is an apparatus for modeling a model from a liquid resin, and the wall of the model supporting means does not remain on the bottom surface of the model after the model and the model supporting means are separated. It has a configuration in which the area of the connection portion between the upper end of each wall in the vertical direction and the model, which constitutes the model supporting means, is reduced so that the amount of the remaining portion is small. With this configuration, the model modeling apparatus of the present invention can realize an apparatus in which the model supporting means can be easily separated from the model.</p><p> Further, in order to solve the above problems, the model modeling apparatus of the present invention has a configuration in which the connection portions are arranged in a perforated pattern. With this configuration, the model modeling apparatus of the present invention can stably support the model, and it is easy to distinguish between the model and the model supporting means, so that a modeled object that can be easily separated can be obtained.</p>

<p> As described above, according to the present invention, the wall of the model supporting means does not remain on the bottom surface of the model after the separation of the model and the model supporting means, or even if it remains, the amount is very small, so that the model supporting means can be easily separated from the model. Methods and devices can be provided.</p>

Hereinafter, desirable embodiments of the present invention will be described with reference to FIGS. 1 to 4. The model supporting method by the model supporting means in the stereolithography of the present invention is a model supporting means 1 having a plurality of cells 3 (small chambers) extending in the vertical direction having a cross section surrounded by a closed wall 2 in the horizontal direction. It consists of a process of stereolithography of the part of the gantry 1b and a process of stereolithography of the part of the support 1a of the model support means 1 at the same time as the modeling of the model 4. Then, in the stereolithography step, the inside of the cell 3 is set as a part of the total length in the peripheral direction of the upper part (including the upper end and the vicinity of the upper end) of the wall 2 around each cell 3 of the model supporting means 1. Form a communication passage 5 that communicates with the outside of the. Each cell 3 is finalized through a passage 5 provided on the surrounding wall forming the cell alone or through another passage 5 provided on the surrounding wall forming another cell connected by the passage 5. It communicates with the outside of the model support means 1. At the site where the communication passage 5 exists, the wall 2 of the cell 3 is formed uncoupled with the model bottom surface 7. The model support structure by the model support means in the stereolithography of the embodiment of the present invention has a cross section surrounded by a closed wall 2 in the horizontal direction and extends in the vertical direction during the stereolithography of the model 4 (small chamber). ) Is stereolithographically modeled on the model supporting means 1 (means consisting of at least one of the support 1a and the gantry 1b), and at least a part of the model 4 is supported by the upper end of the wall 2 around each cell 3 of the model supporting means 1. It consists of a structure. Then, in the above structure, the inside of the cell 3 is the outside of the cell 3 as a part of the total length in the peripheral direction of the upper part (including the upper end and the vicinity of the upper end) of the wall 2 around each cell 3 of the model supporting means 1. A communication passage 5 that communicates with is formed. Each cell 3 is finalized through a passage 5 provided on the surrounding wall forming the cell alone or through another passage 5 provided on the surrounding wall forming another cell connected by the passage 5. It communicates with the outside of the model support means 1. At the site where the communication passage 5 exists, the wall 2 of the cell 3 is formed uncoupled with the model bottom surface 7.

More specifically, the table 6 is submerged in a photocurable resin liquid so that a thin layer of the resin liquid is formed on the table 6, and the resin liquid on the table 6 is irradiated with light (laser) to form a planar shape. A predetermined figure is drawn, the portion is cured to form a cured layer, and then the table 6 is lowered by a predetermined amount to photo-cure the liquid layer on the cured layer, and the cured layers are sequentially laminated and formed. Then, a three-dimensional shape model 4 is formed. If the hardened layer of model 4 is not supported by the lower hardened layer on the entire surface or at the edges, it will hang under its own weight during formation, and to prevent this, support 1a under the layer before forming the layer. Is formed. Support 1a is generated by the same method as model 4 when a hardened layer having the same height is formed, and a model part and a support part are generated. In addition, the gantry 1b may be formed by stereolithography under the support 1a, and the model may be directly supported by the gantry 1b. The combination of the support 1a and the gantry 1b constitutes the model support means 1.

The wall 2 around each cell 3 of the model support means 1 is about 0.3 mm thick. When a plurality of cells 3 are arranged in a grid pattern in the cross section, the wall 2 forms a grid in which the planes are in a grid pattern as shown in FIG. When the wall 2 of the cell 3 is formed by photocuring, the uncured resin liquid in the cell 3 is trapped in the wall 2 forming the closed cross section as it is. The model supporting means 1 is sequentially formed in the height direction, and at the upper end of the model supporting means 1, a communication passage 5 is formed in a part of the peripheral direction of the upper end of the wall 2 around each cell 3. It is formed.

The passage 5 is allowed to take various forms. For example, if the bottom surface 7 of model 4 extends diagonally, linearly or curvedly, the top edge of the wall 2 around the cell is formed diagonally along the bottom surface 7 in a staircase pattern, with corners 8 of this staircase. The model support means 1 and the model 4 are linearly connected only by a single, and the side view formed between the horizontally extending wall upper end 9 at the upper end of each cell 3 and the diagonal model bottom surface 7 creates a triangular gap. Let it be a continuous passage 5. In this case, the upper end of the wall 2 is not connected to the model bottom surface 7 at the site where the communication passage 5 exists. When the bottom surface 7 of the model 4 extends horizontally, at least one upper end of the wall portion 2a extending in the X-axis direction and the wall portion 2b extending in the Y-axis direction among the surrounding wall 2 of each cell 3. A notch 10 is formed, and the opening surrounded by the edge of the notch 10 and the bottom surface 7 of the model is referred to as a continuous passage 5. In this case, the upper end of the wall 2 is not connected to the model bottom surface 7 at the site where the communication passage 5 exists. The configuration in which the wall 2 is not connected to the model bottom surface 7 at the site where the communication passage 5 is present in claims 2 and 4 includes both the above-mentioned stepped and notched cases, and the model bottom surface 7 is connected. Includes all cases forming the upper edge of the edge of passage 5. Further, as shown in FIG. 4, the communication passage 5 may have an opening 11 having an appropriate shape, for example, a slit shape, formed at a position slightly separated downward from the upper end of the wall 2. In this case, the upper end of the wall 2 is connected to the bottom surface 7 of the model even in the portion where the communication passage 5 exists.

At least a part of the model 4 is formed on the upper side of the model supporting means 1. After the stereolithography of the model support means 1 and the model 4 is completed, the model 4 and the model support means 1 are cut at the gantry portion 1b below the model 4, and the integrally modeled object of the model 4 and the model support means 1 is removed from the table 6 and outside the resin liquid layer. Taken out. At this time, outside air can easily enter each cell 3 of the model supporting means 1 through the communication passage 5 above the model supporting means 1, and the resin liquid contained in the cell can easily enter by its own weight. It does not fall out into the resin liquid layer through the opening at the lower end of the cell 3 and stay in the cell 3. Therefore, unlike the conventional case, when the model supporting means 1 is separated from the model 4, the resin axilla that has accumulated in the cell 3 is not opened and falls. Therefore, the resin liquid can be effectively recovered, the cost increase can be suppressed, and the deterioration of the working environment can be prevented.

After being taken out from the resin liquid layer, the model supporting means 1 is separated and removed from the integrally modeled object of the model 4 and the model supporting means 1, and the wall part of the model supporting means remaining on the bottom surface of the model is scraped off with a knife or the like. , The model support means separation surface of model 4 is finished. In this case, since the cell peripheral wall 2 of the model supporting means 1 is only connected to the model 4 by only a part of the total length in the cell peripheral direction, a perforation is made in the model connecting portion of the model supporting means 1. It is in the same state as the above, and can be easily separated along the perforation (communication passage 5). Further, since the support wall does not remain in the portion where the communication passage 5 of the model supporting means is located, or even if it remains, the bottom surface of the model after the model supporting means is separated makes it easy to finish the bottom surface of the model.

<figref num="1">It is a top view of the model support means part of the model support means and the model integrally model obtained during the practice of the method of one Example of this invention, or which concerns on the structure of one Example of this invention.</figref><figref num="2">It is a side view of the model support means of FIG. 1 and the integrated model of the model.</figref><figref num="3">It is a front view seen from the right side of the integrated model of the model supporting means and the model of FIG.</figref><figref num="4">It is a partial side view of the model support means which shows another form of the communication passage formed in the model support means.</figref><figref num="5">It is a top view of the model support means part of the model support means and the model integral model obtained during the practice of the conventional method.</figref><figref num="6">It is a side view of the model support means of FIG. 5 and the integrated model of the model.</figref><figref num="7">It is a front view seen from the right side of the model support means of FIG. 6 and the integrated model of the model.</figref>

Code description

1 Model support means 1a Support 1b Stand 2 (of cell) Wall 3 Cell 4 Model 5 Passage 6 Table 7 Model bottom 8 Square 9 Wall top 10 Notch 11 Opening