JP5552100B2 - Powder sintering modeling method - Google Patents

Description

  The present invention relates to a powder sintering modeling apparatus and a powder sintering modeling method.

The powder sintering modeling apparatus is an apparatus that automatically creates a three-dimensional structure by sequentially melting and sintering powder materials in accordance with the cross-sectional shape of the three-dimensional structure. According to the powder sintering modeling method (SLS method) using this apparatus, slice data of a three-dimensional model to be prepared in advance is prepared, a thin layer of powder material is formed, and the thin layer is formed. By performing drawing heating with a laser based on the slice data, the powder particles are fused to each other to form a sintered thin layer, and by repeating these steps, a plurality of sintered thin layers are laminated to form 3 A three-dimensional structure is produced. Since the model is obtained in a state of being buried in a lump (cake) of uncured powder material, the model is finally dug out of the model. This work is called “breakout”.

  In the above powder sintering modeling method, it is common to preheat the powder material in order to reduce the time required for modeling while maintaining the internal stress between the thin layers low. When the preheating temperature is high, the breakout is made after waiting for the cake temperature to drop.

  By the way, in recent years, an increase in size of a modeled object has been desired. In this case, if the molded article is enlarged, the time required for the heat radiation becomes remarkably long (probably proportional to the square of the dimension), and as a result, there is a risk of causing inefficiency in system operation.

  The present invention was created in view of the problems of the conventional example described above, and shortens the time required for modeling and the time required to take out the completed modeled object while maintaining the internal stress between the thin layers low. A powder sintering modeling apparatus and a powder sintering modeling method that can be performed are provided.

In order to solve the above-mentioned problem, the first invention relates to a powder sinter molding method, and (i) a step of supplying a powder material on a workbench and spreading the powder material to form a thin layer of the powder material; (Ii) a step of selectively heating and sintering the thin layer of the powder material based on a drawing pattern; and (iii) a new thin layer of powder material on the heated and sintered thin layer. Before forming, the gaseous refrigerant is allowed to flow on the surface of the heated and sintered thin layer, and the flow rate of the refrigerant flowing on the surface of the thin layer is maintained in a range in which the flow of the refrigerant becomes a laminar flow. And a step of cooling the heated and sintered thin layer, repeating the steps (i) to (iii), and stacking the sintered thin layers to produce a three-dimensional structure. It is characterized by
A second invention relates to a powder sinter molding method, wherein (i) supplying a powder material on a work table and spreading the powder material to form a thin layer of the powder material; (ii) the powder A step of selectively heating and sintering a thin layer of material based on a drawing pattern; and (iii) before forming a new thin layer of powder material on the heated and sintered thin layer, Gaseous refrigerant is allowed to flow on the surface of the heated and sintered thin layer, the flow rate of the refrigerant flowing on the surface of the thin layer is maintained in a range where the flow of the refrigerant becomes turbulent, and Adjusting the thin layer or the stacked thin layer so as not to rise, cooling the heated and sintered thin layer, and repeating the steps (i) to (iii), It is characterized by stacking the sintered thin layers to produce a three-dimensional structure ,
A third invention relates to the powder sinter molding method of the second invention, wherein the flow rate of the refrigerant flowing on the surface of the thin layer is maintained in a range in which the flow of the refrigerant becomes a turbulent flow, After cooling the thin layer by flowing the refrigerant on the surface, the powder material around the thin layer is smoothed to smooth the surface ,
The fourth invention relates to the powder sinter molding method according to the first or second invention, wherein the steps (i) to (ii) are repeated and heated and sintered before the step (iii). Forming a plurality of thin layers ,
5th invention is related with the powder-sintering shaping | molding method of 1st or 2nd invention, In the process of cooling the said heat-sintered thin layer, the said heat-sintered thin layer has the said surface on the surface Providing a means for guiding the gaseous refrigerant, and flowing the gaseous refrigerant over the surface of the heated and sintered thin layer ,
A sixth invention relates to the powder sinter molding method of the first or second invention, wherein the powder material is nylon, polypropylene, polylactic acid, polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), It is at least one selected from the group consisting of acrylonitrile / butadiene / styrene copolymer (ABS), ethylene / vinyl acetate copolymer (EVA), styrene / acrylonitrile copolymer (SAN), and polycaprolactone.

  The operation based on the configuration of the present invention will be described below.

In the present invention, a gaseous or liquid refrigerant is passed over the surface of the thin layer heated and sintered to cool the thin layer heated and sintered. That is, each time a single layer or a suitable thin layer is heated and sintered, it is cooled.

  In this case, since the heat capacity of the object to be cooled is small, the temperature of the object to be cooled can be lowered in a short time. Moreover, by continuing such a method, the temperature of the three-dimensional structure remains low even when the three-dimensional structure is completed. Thereby, the completed molded object can be taken out immediately without the waiting time for cooling. As described above, the time required to take out the completed model including the cooling time during the modeling can be greatly reduced.

  In addition, regarding the internal stress, the temperature gradient between the inside and outside of the cake is cooled because one or a plurality of appropriate thin layers are cooled without preheating the intermediate object that has already been formed. It is possible to prevent the occurrence of stress due to.

In particular, gaseous refrigerant is used as a cooling means, and a cooling medium guide is provided above the work table so that at least a plane facing the work table can move up and down, and between the work table and the plane of the refrigerant guide. If allowed to flow the refrigerant, by adjusting the spacing between the workbench and the refrigerant guide plane, it can be adjusted such that the flow of the refrigerant becomes a laminar flow. Thereby, a turbulent flow can be prevented and it can suppress that a non-hardened powder material, the thin layer in the middle of modeling, or the stacked thin layer rises. In some cases, the flow rate of the refrigerant may be maintained at a flow rate at which turbulent flow occurs. This further increases the cooling effect. In this case, it is necessary to adjust and weaken the flow rate so that the thin layer in the middle of modeling or the stacked thin layer does not rise.

  Further, the refrigerant may be directly blown to cool a thin layer heated and sintered without providing the refrigerant guide. In this case, even if the surrounding uncured powder material soars, for example, by smoothing the surface by smoothing the powder material around the thin layer with a roller for supplying the powder material, the thin layer and the surrounding powder material Can be cooled quickly and the next thin layer can be formed immediately thereafter.

  When a liquid refrigerant is used, the thin layer can be cooled by spraying the refrigerant on the surface of the thin layer and causing the refrigerant to remove heat from the thin layer when the refrigerant evaporates.

  As described above, according to the present invention, each time a single layer or a suitable plurality of thin layers are heated and sintered, they are cooled. However, since the heat capacity of the object to be cooled is small, it is cooled in a short time. can do. In addition, by continuing such a method, the temperature of the three-dimensional structure remains low even when the three-dimensional structure is completed, so that the time until the breakout is started can be greatly shortened. As described above, the time required to take out the completed three-dimensional structure including the cooling time in the middle of the modeling can be greatly shortened, thereby improving the efficiency in system operation.

  In addition, since a large internal stress due to rapid cooling does not occur in the three-dimensional structure, a model with high accuracy can be produced.

  Embodiments of the present invention will be described below with reference to the drawings.

(Description of powder sinter molding equipment)
FIG. 1 is a perspective view showing a configuration of a powder sinter molding apparatus according to an embodiment of the present invention.

  This powder sintering modeling apparatus 101 includes a laser beam emitting unit 101A, a modeling unit 101B, and a control device 101C.

  The laser beam emitting unit 101A is provided with a laser beam light source 1 and a mirror 2 for controlling the laser beam irradiation direction. The laser beam emitted from the light source 1 is selectively irradiated to the thin layer of the powder material 8 on the part cylinder 6 of the modeling unit 101B by mirror control by a computer. For example, mirror control by a computer is performed based on slice data (drawing pattern) of a three-dimensional structure to be produced. The laser light source 1 and the mirror 2 constitute a heating and sintering means.

  In the modeling part 101B, modeling is performed by irradiation of laser light thereon, and a part cylinder (workbench) 6 that can be moved up and down to produce a three-dimensional modeled object is installed in the central container 4 on both sides thereof. Feed cylinders 5a and 5b that can be moved up and down by placing the powder material 8 in containers 3a and 3b for storing the powder material are respectively installed. Further, a recoater roller (thin layer forming means) 7 is provided that moves while rotating over the entire area. The recoater roller 7 moves while rotating to supply the powder material 8 stored on the feed cylinder 5 b onto the part cylinder 6, and level the surface of the powder material 8 to powder onto the part cylinder 6. It has a function of forming the thin layer 8a of the material 8. Therefore, the supply amount of the powder material 8 is determined by the rising amount of the feed cylinder 5 b, and the thickness of the thin layer 8 a of the powder material is determined by the lowering amount of the part cylinder 6. As powder material 8, nylon, polypropylene, polylactic acid, polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), acrylic, tolyl / butadiene / styrene copolymer (ABS), ethylene / vinyl acetate copolymer (EVA), styrene -At least 1 sort (s) chosen from the group which consists of an acrylonitrile copolymer (SAN) and polycaprolactone can be used.

  Further, a refrigerant guide 11 having a flat surface facing the part cylinder 8 is disposed above the part cylinder 8, and the thin layer 8 b on the part cylinder 6 and the surface of the powder material 8 remaining in the periphery thereof and the refrigerant guide 11. A refrigerant flow path is formed between the opposite planes. A gaseous refrigerant such as cooling air or cooling nitrogen is used as the refrigerant. A refrigerant supply source (not shown) is connected to the end of the pipe 13 so that the refrigerant can be introduced into the refrigerant flow path. The refrigerant guide 11 can be moved up and down and moved in a plane. By moving the refrigerant guide 11 up and down, the distance between the thin layer 8b on the part cylinder 6 and the surface of the powder material 8 remaining around the thin layer 8b and the opposed plane of the refrigerant guide 11 can be adjusted. . Further, by moving in a plane, irradiation of the laser beam to the thin layer 8a of the powder material is not hindered.

  Next, a configuration of the refrigerant guide 11 and a method for controlling the flow rate of the refrigerant by the refrigerant guide 11 will be described with reference to FIGS. 2 (a) and 2 (b).

  The refrigerant guide 11 has a square shape as viewed from above as shown in FIG. 1 and a cross-sectional shape as viewed from the side as shown in FIGS. 2 (a) and 2 (b). It has such a shape. This shape corresponds to the arrangement of the left feed cylinder 5a, the center part cylinder 6 and the right feed cylinder 5b of the modeling part 101B. That is, the refrigerant guide 11 has a flat surface corresponding to the part cylinder 6 corresponding to the bottom surface of the bathtub, and the flat surface is at least as large as the upper surface of the part cylinder 6. The portions corresponding to the feed cylinders 5a and 5b are raised so as to draw a curve from the bottom surface corresponding to the periphery of the bathtub. In this case, the portion corresponding to the left feed cylinder 5a has a cross-sectional shape such that the bowl is turned down so that the refrigerant does not escape when viewed from the side, and the refrigerant inlet 12 is provided almost at the top. . On the other hand, a portion corresponding to the right feed cylinder 5b is opened so as to dissipate the refrigerant, and serves as an outlet 14 for the refrigerant.

  The refrigerant guide 11 is placed so that the flat surface faces the part cylinder 6. A flow path is formed between the flat surface of the refrigerant guide 11 and the surface of the thin layer 8b and the powder material 8a placed on the part cylinder 6. In order to adjust the flow rate of the refrigerant, the height of the flow path is adjusted. The refrigerant is introduced from the refrigerant inlet 12 on the left side of FIG. 2A and flows through the flow path below the flat surface of the refrigerant guide 11 to the refrigerant outlet 14 on the right side.

  According to the wind tunnel experiment of the inventor of the present application, when the Reynolds number (Re) is about 1700 or less, laminar flow is obtained, and when the Reynolds number (Re) is about 1700 or more, turbulent flow is generated. What has become clear from this experiment is that the surface of the powder can be cooled by laminar flow, and that the powder rises by turbulent flow.

  In the present invention, when the refrigerant is flowed using the refrigerant guide 11, the height of the flow path of the refrigerant below the flat surface of the refrigerant guide 11 is set so that the flow of the refrigerant becomes a laminar flow so that the powder material 8a does not rise. adjust.

  The control device 101C lowers the part cylinder 6 by one thin layer, causes the recoater roller 7 to supply the powder material 8 onto the part cylinder 6, and forms a thin layer 8a of the powder material on the part cylinder 6. Next, the thin layer 8a of the powder material is selectively heated and sintered based on the laser beam and the slice data (drawing pattern) of the three-dimensional structure to be produced by the control mirror 2 (heating and sintering means), and then One layer or a plurality of stacked thin layers 8b heated and sintered are cooled by cooling means.

(Other cooling means)
Next, other first to eighth cooling means in the modeling unit 101B will be described with reference to FIGS.

  FIG. 8A is a side view showing the configuration of another first cooling unit and the device configuration that does not prevent laser light irradiation.

  The other first cooling means includes a refrigerant supply means and a refrigerant guide 11a.

  As shown in FIG. 8A, the refrigerant guide 11a has a planar portion 22a facing the part cylinder 6 attached to the main body 21a by an expandable / contractible bellows 23a. When forming the refrigerant flow path, the planar portion 22a is moved downward by the push-down shaft 24a. When the powder material 8 is supplied and the laser beam is irradiated, the planar portion 22a is raised.

  In addition, laser windows 25a and 25b are provided in the main body 21a and the plane portion 22a so that the laser beam passes when the plane portion 22a is raised during the laser beam irradiation.

  In addition, the other code | symbol shows the same code | symbol as FIG. 1 and the same code | symbol as FIG.

  FIG. 8B is a side view showing another configuration of the second cooling means and another device configuration for supplying the refrigerant.

  The other second cooling means is also composed of the refrigerant supply means and the refrigerant guide 11b.

  The refrigerant guide 11b is attached to the main body 21b by a bellows 23b whose plane portion 22b facing the part cylinder 6 is extendable. When forming the refrigerant flow path, the flat portion 22b is moved downward by the push-down shaft 24b. When the powder material 8 is supplied and the laser beam is irradiated, the planar portion 22b is raised.

  The difference from FIG. 8A is that the square case 26b having a depth is turned upside down so as to cover a necessary region so that the refrigerant does not flow out except where the cooling target is present. The refrigerant inlet 12b and the outlet 14b are provided in the case 26b via a bellows 23b.

  In addition, the other code | symbol shows the same code | symbol as FIG. 1 and the same code | symbol as FIG.

  Fig.9 (a) is a perspective view shown about an example of the installation method of the refrigerant | coolant guide 11c in another 3rd cooling means.

  The other third cooling means is also composed of the refrigerant supply means and the refrigerant guide 11c.

  The difference from FIG. 8B is that the refrigerant guide 11d is provided with only a square case 26c having a depth without a main body and a push-down shaft. One side of the square case 26c is fixed. The case 26c can be lifted from the opposite side of the fixed side when supplying the powder material 8 or irradiating the laser beam.

  In FIG. 9A, the other reference numeral 12c is a refrigerant inlet, 14c is a refrigerant outlet, and 13c is a bellows through which the refrigerant flows. The other reference numerals are the same as those in FIG. 1, and the same reference numerals as those in FIG.

  FIG. 9B is a perspective view showing the configuration of another fourth cooling means and a refrigerant supply method.

  The difference from FIG. 9A is that the entire cooling means is made to move together with the recoater rollers 7a and 7b. In the figure, means for fixing the cooling means to the recoater rollers 7a and 7b is omitted, but for example, the cooling means can be fixed to a support shaft inserted in the center of the recoater rollers 7a and 7b. .

  In FIG. 9 (b), the other reference numeral 26d is a square case having a depth, 22d is a plane portion of the case 26d facing the part cylinder 6, 13d is a bellows through which refrigerant flows, and 27 is a refrigerant guided to the case 26d. It is a flow passage surrounded by plates.

  FIG. 10A is a side view for explaining the configuration of another fifth cooling means and the cooling method.

  The other first to fourth cooling means use a gaseous refrigerant supply means and refrigerant guides 11a to 11d for adjusting the flow rate of the refrigerant, but the gaseous state as shown in FIG. Only the refrigerant supply means 27a may be used. In this case, the powder material 8 a rises due to the discharge of the refrigerant, but the surface of the powder material 8 a that is uneven due to the rise is leveled using the recoater roller 7. Thereafter, in order to form a thin layer of the next powder material, the part cylinder 6 is lowered to supply new powder material. In FIG. 10A, another reference numeral 12e is a refrigerant inlet.

  FIG.10 (b) is a side view which shows the structure of the modification of a 5th cooling means. The cooling means of FIG. 10B includes two recoater rollers 7c and 7d. Pipes through which the refrigerant flows are used as the rotating shafts, and refrigerant inlets 12f and 12g of the refrigerant supply pipe 27b are connected to the pipes. The recoater rollers 7c and 7d are movable while rotating on the powder material 8a while maintaining an appropriate interval. The two recoater rollers 7c and 7d supply the powder material and flatten the surface of the powder material.

  Unlike the other cooling means, the cooling means shown in FIGS. 10 (a) and 10 (b) can be expected to be efficiently cooled by intentionally raising the powder material. When the stack of thin layers stacked so far is small, there is a risk that the thin layer or the stack of thin layers may rise by the discharge of the coolant. Consideration such as weakening is necessary.

  In addition to the cooling means described in the above drawings, the following sixth to eighth cooling means can be used.

  As another sixth cooling means, a liquid refrigerant supply means may be used. Alternative chlorofluorocarbon, alcohol, water, liquid air, or the like can be used as the liquid refrigerant. In this case, when the refrigerant is sprayed on the surface of the heated and sintered thin layer and the refrigerant evaporates, the thin layer can be cooled by removing heat from the thin layer.

  Further, by cooling the recoater roller as another seventh cooling means, the recoater roller itself can also function as the cooling means.

  As another eighth cooling means, a cooling plate having a contact surface with a thin layer heated and sintered can be newly provided. In this case, the cooling plate is cooled and the contact surface is brought into contact with the thin layer to cool the thin layer. Further, for example, a refrigerant guide as shown in FIG.

  The cooling methods realized by the above-described FIG. 1 and the other first to eighth cooling means are four types of cooling methods shown in P4-1, P4-2, P4-3, and P4-4 in FIG. It corresponds to any one of them. In summary:

  The cooling method realized by FIG. 1 and the other first to fourth cooling means corresponds to P4-1, the cooling method realized by the other fifth cooling means corresponds to P4-2, and the like. The cooling method realized by the sixth cooling means corresponds to P4-3, and the cooling methods realized by the other seventh and eighth cooling means correspond to P4-4.

  According to the powder sinter molding apparatus 101 as described above, there is a control unit that cools, by a cooling unit, one or a plurality of stacked thin layers heated and sintered. That is, each time a single layer or appropriate thin layers are heated and sintered, they are cooled.

  In this case, since the heat capacity of the object to be cooled is small, the temperature of the object to be cooled can be lowered in a short time. Moreover, by continuing such a method, the temperature of the three-dimensional structure remains low even when the three-dimensional structure is completed. Thereby, the time required for breakout can be shortened. As described above, the time required to take out the completed model including the cooling time during the modeling can be greatly reduced.

  In addition, regarding the internal stress, the temperature gradient between the inside and outside of the cake is cooled because one or a plurality of appropriate thin layers are cooled without preheating the intermediate object that has already been formed. It is possible to prevent the occurrence of stress due to.

(Explanation of powder sintering modeling method)
Next, with reference to FIG. 3 and FIG. 5 to FIG. 7, a powder sintering modeling method according to an embodiment of the present invention will be described. FIG. 3 is a flowchart illustrating the powder sintering modeling method, and FIGS. 5 to 7 are process cross-sectional views illustrating the powder sintering modeling method. In this case, the powder sintering apparatus of FIG. 1 is used, and a gaseous refrigerant is used as the refrigerant.

  First, as shown in FIG. 5A, in the modeling part 101B, the left and right feed cylinders 5a and 5b are lowered, and the powder material 8 is supplied onto the feed cylinders 5a and 5b. Save it.

  Next, as shown in FIG. 5B, the part cylinder 6 is lowered by an amount corresponding to one thin layer (P1 step in FIG. 3). Next, the right feed cylinder 5b is raised so that the powder material 8 comes out from the flat surface.

  Next, as shown in FIG. 5 (c), the recoater roller 7 is rotated to move the powder material 8 on the right feed cylinder 3b and above the flat surface to the part cylinder 6 while leveling it. . As a result, as shown in FIG. 6A, a thin layer 8a of one layer of powder material is formed on the part cylinder 6 (step P2 in FIG. 3).

  Next, as shown in FIG. 6B, the laser beam is emitted from the light source 1 of the laser beam emitting unit 101A, and the mirror 2 is controlled by a computer based on the slice data of the three-dimensional structure to be produced. The thin layer 8a of powder material is selectively irradiated with laser light. Thereby, the thin layer 8b of powder material is heated and sintered (P3 process of FIG. 3).

  Next, as shown in FIG. 6 (c), the refrigerant guide 11 is moved onto the part cylinder 6 and further lowered to sinter the flat surface of the refrigerant guide 11 and the part cylinder 6. The height of the flow path formed between the thin layer 8b and the surface of the powder material 8a remaining around the thin layer 8b is adjusted. In this case, the height of the flow path is adjusted so that a laminar flow is generated in the refrigerant flowing through the flow path. For example, the height is about 10 mm.

  Next, the refrigerant is caused to flow from the refrigerant inlet 12 to the flow path to cool the sintered thin layer 8b on the part cylinder 6 and the powder material 8a remaining around the thin layer 8b (step P4 in FIG. 3). In this case, since the flow of the refrigerant is a laminar flow, the powder material 8a around the thin layer 8b can be maintained as it is without flying up. In particular, it is effective in the case of producing a small shaped object, for example, when it is not desired to fly the powder material and redistribute it on the part cylinder 6.

  In addition, since the heat capacity of the cooling target composed of one thin layer is small, the temperature of the cooling target can be lowered in a short time. As for internal stress, since it is cooled for each thin layer without preheating the intermediate object that has already been formed, stress due to the temperature gradient between the inside and outside of the cake is generated. Can be prevented.

  Next, as shown in FIG. 7A, the part cylinder 6 is lowered by one thin layer and the feed cylinder 5b is raised. Thereafter, in the same manner as described above, a new powder material 8 is supplied onto the part cylinder 6 and, as shown in FIG. 7B, a new powder material thin layer is formed on the sintered thin layer 8b. 8a is formed. Next, in the same manner as shown in FIGS. 6B, 6C, 7A, and 7B, heat sintering → cooling → formation of a thin layer 8a of powder material → heat sintering → Repeat the process.

  In this way, a three-dimensional structure is completed. At this time, the temperature of the three-dimensional structure remains low even immediately after the completion of the three-dimensional structure. Therefore, after the three-dimensional structure is completed, the three-dimensional structure can be taken out without taking time.

  As described above, in the powder sinter molding method according to the embodiment of the present invention, cooling is performed every time the thin layers heated and sintered are stacked. In this case, since the heat capacity of the object to be cooled is small, the temperature of the object to be cooled can be lowered in a short time. Moreover, by continuing such a method, the temperature of the three-dimensional structure remains low even immediately after the completion of the three-dimensional structure. As a result, it is possible to shorten the time until the breakout is started. As described above, the time required to take out the completed model including the cooling time during the modeling can be greatly reduced.

  As for internal stress, it is possible to prevent large internal stress due to temperature gradient between the inside and outside of the modeled object by quenching in a thin layer. Can be produced.

  Although the present invention has been described in detail with the embodiments, the scope of the present invention is not limited to the examples specifically shown in the above embodiments, and the above embodiments within the scope of the present invention are not deviated. Variations in form are within the scope of this invention.

  For example, in the powder sintering molding method of this embodiment, as shown in FIGS. 6B, 6C, 7A, and 7B, one thin layer 8a is heated and sintered. Before cooling, the thin layer formation and heat sintering are repeated multiple times to form an appropriate multiple layer within a range where the heat capacity does not become too large, and then the multiple layers are formed. You may cool collectively.

It is a perspective view which shows the structure of the powder sintering modeling apparatus which is embodiment of this invention. (A) is sectional drawing shown about the structure of the cooling means of the powder sintering modeling apparatus which is embodiment of this invention, and the installation method of the refrigerant guide of a cooling means. (B) is a figure explaining the method of making a laminar flow and a turbulent flow using the refrigerant | coolant guide of a cooling means. It is a flowchart shown about the powder sintering modeling method which is embodiment of this invention. It is a figure shown about the cooling method in the powder sintering modeling method which is embodiment of this invention. It is sectional drawing (the 1) shown about the powder sintering modeling method which is embodiment of this invention. It is sectional drawing (the 2) shown about the powder sintering modeling method which is embodiment of this invention. It is sectional drawing (the 3) shown about the powder sintering modeling method which is embodiment of this invention. (A), (b) is a side view shown about the structure of the other 1st, 2nd cooling means in the powder sintering modeling apparatus which is embodiment of this invention. (A), (b) is a perspective view shown about the structure of the other 3rd, 4th cooling means in the powder sintering modeling apparatus which is embodiment of this invention. (A), (b) is a side view shown about the structure of the other 5th cooling means in the powder sintering modeling apparatus which is embodiment of this invention, and its modification.

1 Laser light source (laser light emitting means)
2 Mirror (Laser light emitting means)
3a, 3b, 4 Container 5a, 5b Feed cylinder 6 Part cylinder (work bench)
7, 7a, 7b, 7c, 7d Recoater roller (thin layer forming means)
8 Powder material 8a Thin layer 8b of powder material Sintered thin layers 11, 11a, 11b, 11c, 11d Refrigerant guides 12, 12a, 12b, 12c, 12e, 12f, 12g Refrigerant inlets 14, 14a, 14b, 14c Refrigerant outlet 101A Laser beam emitting unit 101B Modeling unit 101C Control device

Claims (6)

(I) supplying a powder material on a workbench and spreading the powder material to form a thin layer of the powder material;
(Ii) a step of selectively heating and sintering the thin layer of the powder material based on a drawing pattern;
(Iii) the heated before forming a thin layer of new powder material onto a sintered thin layer, by flowing a gaseous coolant to the surface of the heated sintered thin layer, the thin Maintaining the flow rate of the refrigerant flowing on the surface of the layer in a range in which the flow of the refrigerant becomes a laminar flow, and cooling the heated and sintered thin layer,
A powder sinter molding method characterized by repeatedly performing the steps (i) to (iii) and stacking the sintered thin layers to produce a three-dimensional structure. (I) supplying a powder material on a workbench and spreading the powder material to form a thin layer of the powder material;
(Ii) a step of selectively heating and sintering the thin layer of the powder material based on a drawing pattern;
(Iii) the heated before forming a thin layer of new powder material onto a sintered thin layer, by flowing a gaseous coolant to the surface of the heated sintered thin layer, the thin The flow rate of the refrigerant flowing on the surface of the layer is maintained in a range in which the flow of the refrigerant becomes a turbulent flow, and is adjusted so that the thin layer or the stacked thin layer in the middle of modeling does not rise, and the heating is performed. And cooling the sintered thin layer,
A powder sinter molding method characterized by repeatedly performing the steps (i) to (iii) and stacking the sintered thin layers to produce a three-dimensional structure. After the flow rate of refrigerant flowing on the surface of the thin layer flow of the refrigerant is maintained in the range such that turbulence was cooling the thin layer by flowing the refrigerant to the surface of the thin layer, the thin layer around 3. The powder sintering method according to claim 2, wherein the powder material is smoothed to smooth the surface. 3. The powder firing according to claim 1 , wherein the steps (i) to (ii) are repeated to form a plurality of thin layers heated and sintered before the step (iii). Forming method. In the step of cooling the heated and sintered thin layer, the surface of the heated and sintered thin layer is provided with means for introducing the gaseous refrigerant to the surface of the heated and sintered thin layer. 3. The powder sintering molding method according to claim 1 or 2 , wherein the gaseous refrigerant is flowed through the apparatus. The powder materials are nylon, polypropylene, polylactic acid, polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), acrylonitrile-butadiene-styrene copolymer (ABS), ethylene-vinyl acetate copolymer (EVA), styrene- 3. The powder sintered molding method according to claim 1, wherein the method is at least one selected from the group consisting of acrylonitrile copolymer (SAN) and polycaprolactone.

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