WO2018042526A1

WO2018042526A1 - Method and device for manufacturing three-dimensional laminated molding

Info

Publication number: WO2018042526A1
Application number: PCT/JP2016/075381
Authority: WO
Inventors: 一穂森本; 敦司廣田; 博文石黒
Original assignee: 株式会社Ｏｐｍラボラトリー
Priority date: 2016-08-31
Filing date: 2016-08-31
Publication date: 2018-03-08

Abstract

Provided are a method and a device for manufacturing a three-dimensional laminated molding, which are capable of suppressing the formation of projected and recessed parts on the surface of the three-dimensional laminated molding by suppressing the occurrence of roughening the side surface of a solidified layer caused by powder material. The three-dimensional laminated molding is manufactured by forming solidified layers in which the powder material is irradiated with an energy beam so as to be solidified, laminating the solidified layers, and cutting the laminated solidified layers. The cutting process includes: a finishing step for cutting at least some parts of the solidified layers into necessary shapes by a first rotary cutting tool; and a removal step for removing the powder material from around the solidified layers by moving a rod-like tool larger in diameter than the first cutting tool around the solidified layers along the side surface of the solidified layers before the finishing step.

Description

Manufacturing method and manufacturing apparatus for three-dimensional layered object

The present invention relates to a method and a manufacturing apparatus for manufacturing a three-dimensional layered object by stacking solidified layers obtained by solidifying material powder.

A material powder such as a metal powder is irradiated with an energy beam such as a laser beam, and the material powder is sintered or melted and solidified to form a solidified layer, and the solidified layer is laminated to form a three-dimensional shape. There is a method of manufacturing a three-dimensional layered object by adding a cutting process in the middle of forming. Hereinafter, this manufacturing method is referred to as an optical modeling composite processing method.

In the stereolithography combined processing method, a plurality of solidified layers are stacked, and the plurality of solidified layers are collectively cut. In the cutting process, the side surfaces of the plurality of solidified layers are cut, and the side surfaces of the solidified layers thus cut finally become the surface of the three-dimensional layered object. However, when a new solidified layer is formed and laminated on the solidified layer that has been cut, the solidified layer that has already been cut may be deformed by the influence of heat from the new solidified layer. . For this reason, there exists a problem that an unevenness | corrugation arises on the surface of a three-dimensional laminate modeling thing. Therefore, in the conventional stereolithography combined processing method, rough finishing that leaves a slightly large finishing allowance from the desired shape is performed at the time of cutting, and to a certain degree of solidified layer that is not affected by the heat from the new solidified layer Then, finish to the desired shape. By this method, the generation of irregularities on the surface of the three-dimensional layered object is suppressed. Patent Document 1 describes an example of a conventional stereolithography combined processing method.

JP 2007-204828 A

However, even when the cutting process is divided into rough finishing and finishing, unevenness may occur on the surface of the three-dimensional layered object. In particular, as the number of the plurality of solidified layers subjected to the cutting process together increases, unevenness is more likely to occur. Even when the cutting process is divided into rough finishing and finishing, one of the causes of unevenness is that the material powder present around the three-dimensional layered product in the process of roughing the side of the solidified layer during cutting It is considered that. When the number of the plurality of solidified layers subjected to the cutting process is reduced, it is possible to suppress the generation of irregularities on the surface of the three-dimensional layered object, but there is a problem that the manufacturing time is lengthened.

The present invention has been made in view of such circumstances, and the object of the present invention is to prevent unevenness of the surface of the three-dimensional layered object by suppressing the material powder from roughening the side surface of the solidified layer. It is in providing the manufacturing method and manufacturing apparatus of a three-dimensional layered product which can suppress generation | occurrence | production of this.

The manufacturing method of the three-dimensional layered object according to the present invention includes forming a solidified layer obtained by solidifying the material powder by irradiation of an energy beam to the material powder, laminating the solidified layer, and laminating the plurality of solidified layers. In the method of manufacturing a three-dimensional layered object by performing cutting on the cutting process, the cutting process is performed by cutting at least a part of the plurality of solidified layers into a required shape with the rotating first cutting tool. The finishing step to be performed, and before the finishing step, by moving a rod-shaped tool having a diameter larger than that of the first cutting tool around the plurality of solidified layers along the side surfaces of the plurality of solidified layers, And a removing step of removing the material powder from the periphery of the plurality of solidified layers.

The method for manufacturing a three-dimensional layered object according to the present invention is characterized in that the removing step removes the material powder to a position deeper than a deepest position of the first cutting tool in the finishing step.

In the method for producing a three-dimensional layered object according to the present invention, the cutting step includes a rough finishing step of cutting at least a part of the plurality of solidified layers with a second cutting tool before the removing step. The finishing step cuts at least a part of a portion that has already been cut by the rough finishing step, and the removal step includes side surfaces of the plurality of solidified layers cut by the rough finishing step. The bar-shaped tool is moved at a predetermined distance from the tool.

The manufacturing method of the three-dimensional layered object according to the present invention includes a lifting table on which the material powder is placed and the plurality of solidified layers are stacked, and the lifting table to hold the material powder on the lifting table. And the removing step is performed in a state where the lifting table is raised until the position of the portion to be cut of the plurality of solidified layers is higher than the upper end of the wall. It is characterized by being.

The manufacturing method of the three-dimensional layered object according to the present invention includes a lifting table on which the material powder is placed and the plurality of solidified layers are stacked, and the lifting table to hold the material powder on the lifting table. The wall is formed with a discharge portion for discharging the material powder, and in the step of forming and laminating the solidified layer, the mounting surface of the lifting table is formed by the discharge portion from the discharge portion. The cutting step is performed by lowering the lifting table until the position of the mounting surface is lower than a part of the discharge portion, and the mounting surface described above. And elevating the elevating table until the position becomes higher than the discharge unit, and the removing step is performed after the elevating table is lowered and raised.

An apparatus for manufacturing a three-dimensional layered object according to the present invention forms a solidified layer obtained by solidifying the material powder by irradiation of an energy beam to the material powder, and stacks a plurality of stacked layers. An apparatus for manufacturing a three-dimensional layered object, wherein the cutting unit needs at least a part of the plurality of solidified layers by a rotating cutting tool. A finishing part that cuts into a desired shape, and before cutting by the finishing part, a rod-shaped tool having a diameter larger than that of the cutting tool is disposed around the plurality of solidified layers along the side surfaces of the plurality of solidified layers. And a removing unit that removes the material powder from the periphery of the plurality of solidified layers by being moved.

The apparatus for manufacturing a three-dimensional layered object according to the present invention includes a lift table on which the material powder is placed and the plurality of solidified layers are stacked, and the lift table to hold the material powder on the lift table. A wall that surrounds the plurality of solidified layers when the removal portion is operated by the removal portion until a position of a portion to be cut of the plurality of solidified layers is higher than an upper end of the wall. It further has a raising part which raises the raising / lowering table.

The apparatus for manufacturing a three-dimensional layered object according to the present invention includes a lift table on which the material powder is placed and the plurality of solidified layers are stacked, and the lift table to hold the material powder on the lift table. And a wall for forming a discharge portion for discharging the material powder, and the stacking portion is positioned higher than the discharge portion. The solidified layer is formed and laminated in a state, and the cutting unit is a lowering unit that lowers the lifting table until the position of the placement surface is lower than a part of the discharge unit, And a second ascending unit that raises the elevating table until the position of the placement surface is higher than the discharge unit, and the removing unit operates the descending unit and the second ascending unit Characterized by performing work later

In the present invention, the manufacturing apparatus that manufactures the three-dimensional layered object by the optical modeling composite processing method, before the finishing process of cutting a plurality of solidified layers into a necessary shape by the first cutting tool in the cutting process. In addition, a removal step of removing the material powder from the periphery of the solidified layer to be cut is performed. In the removing step, the material powder is removed by moving a rod-shaped tool having a diameter larger than that of the first cutting tool around the solidified layer along the side surface of the solidified layer. During the finishing process, the material powder is less likely to come into contact with the first cutting tool, and the material powder in contact with the first cutting tool is suppressed from roughening the side surface of the solidified layer.

In the present invention, the material powder is removed in the removing step up to a position deeper than the position of the first cutting tool in the finishing step. For this reason, it becomes difficult for the material powder to come into contact with the first cutting tool during the finishing process.

In the present invention, a rough finishing process of cutting a plurality of solidified layers with the second cutting tool is performed, and a finishing process is performed after the rough finishing process. In the removal process, the bar-shaped tool moves at a predetermined distance from the side surface of the solidified layer cut in the rough finishing process. Thereby, material powder is removed from the circumference | surroundings of the solidification layer used as the object of a finishing process.

In the present invention, the manufacturing apparatus includes an elevating table on which material powder is placed and a solidified layer is stacked, and a wall surrounding the elevating table. The removing step is performed in a state where the lifting table is raised until the position of the solidified layer to be cut is higher than the upper end of the wall. Since the metal powder is discharged to the outside beyond the upper end of the wall, the material powder is effectively removed.

In the present invention, the manufacturing apparatus includes an elevating table on which material powder is placed and a solidified layer is stacked, and a wall surrounding the elevating table. The wall is formed with a discharge portion for discharging the material powder. The manufacturing apparatus temporarily lowers the lifting table until the position of the placement surface is lower than a part of the discharge portion, and raises the position until the position of the placement surface is higher than the discharge portion. The removing process is performed after the lift table is lowered and raised. When the lifting table is once lowered, a part of the metal powder is discharged to the outside through the discharge portion. For this reason, removal of material powder is performed effectively.

In the present invention, since the material powder is suppressed from roughening the side surface of the solidified layer when finishing the cutting process, the occurrence of unevenness on the surface of the three-dimensional layered object is suppressed. Therefore, the present invention has an excellent effect such that it is possible to manufacture a high-quality three-dimensional layered object with less surface irregularities while avoiding an increase in manufacturing time.

It is a typical fragmentary sectional view showing the composition of the manufacturing device of the three-dimensional layered object concerning Embodiment 1. It is a typical fragmentary sectional view which shows the process of the optical shaping composite processing method. It is a typical fragmentary sectional view which shows the process of the optical shaping composite processing method. It is a typical fragmentary sectional view which shows the process of the optical shaping composite processing method. It is a typical fragmentary sectional view which shows the process of the optical shaping composite processing method. It is a typical sectional view showing the state where a new modeling layer was laminated on a plurality of modeling layers. 3 is a flowchart illustrating a procedure of a cutting process according to the first embodiment. It is typical sectional drawing which shows a rough finishing process. FIG. 3 is a schematic cross-sectional view showing a removal process according to Embodiment 1. 5 is a schematic cross-sectional view showing a finishing process according to Embodiment 1. FIG. 5 is a schematic cross-sectional view showing a finishing process according to Embodiment 1. FIG. It is the figure which showed the photograph of the three-dimensional layered object manufactured with the manufacturing method which concerns on Embodiment 1, and the conventional manufacturing method. 10 is a flowchart showing a procedure of a cutting process according to the second embodiment. It is a typical fragmentary sectional view which shows the state of a part of manufacturing apparatus at the time of performing the removal process which concerns on Embodiment 2. FIG. 10 is a schematic cross-sectional view showing a removal process according to Embodiment 2. FIG. 10 is a schematic cross-sectional view showing a finishing process according to Embodiment 2. FIG. It is typical sectional drawing which shows the structure of a part of manufacturing apparatus of the three-dimensional laminate modeling thing which concerns on Embodiment 3. FIG. 10 is a flowchart illustrating a procedure of a cutting process according to the third embodiment. It is a typical fragmentary sectional view which shows the state which lowered the raising / lowering table.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
(Embodiment 1)
FIG. 1 is a schematic partial cross-sectional view illustrating a configuration of a three-dimensional layered object manufacturing apparatus 1 according to the first embodiment. The manufacturing apparatus 1 irradiates a metal powder (material powder) with laser light (energy beam), sinters the metal powder to form a solidified layer, and stacks the solidified layer to form a three-dimensional shape. A stereolithography combined processing method is performed in which cutting is performed during the formation of the original shape. The manufacturing apparatus 1 includes a lifting table 12 that can be lifted while holding a modeled object, a wall 13 that surrounds the lifting table 12, and a blade 14 that applies metal powder 4 onto the lifting table 12. The wall 13 holds the metal powder 4 placed on the lifting table 12 so as not to spill from the lifting table 12 when the blade 14 is applied. The lifting table 12 moves up and down in the space surrounded by the wall 13.

In addition, the manufacturing apparatus 1 applies a laser light source 31 for irradiating the metal powder 4 on the lifting table 12 with laser light, a mirror 32 for reflecting the laser light, a lens 33 for condensing the laser light, and a modeling object. And a cutting machine 2 that performs the cutting process. The laser light source 31 uses a laser that can effectively heat the metal powder 4 such as a fiber laser. By moving the mirror 32, the position where the metal powder 4 is irradiated with the laser light is adjusted. In FIG. 1, laser light is indicated by arrows. In addition to the mirror 32 and the lens 33, the manufacturing apparatus 1 may include an optical system for adjusting the irradiation position of the laser light. The cutting machine 2 includes a first cutting tool 21 for performing finishing, a second cutting tool 22 for performing rough finishing, and a rod-shaped tool 23 for removing the metal powder 4.

Furthermore, the manufacturing apparatus 1 includes a control unit 11 that controls the operation of the entire manufacturing apparatus 1. The control unit 11 includes a calculation unit that performs calculation for controlling the operation, a memory that stores information associated with the calculation, a storage unit that stores a control program, and the like. The control unit 11 controls the operation of each part constituting the manufacturing apparatus 1, and controls the irradiation position of the laser light irradiated to the metal powder 4 and the cutting position of the shaped object cut by the cutting machine 2.

An outline of the stereolithography combined processing method will be described. 2 to 5 are schematic partial cross-sectional views showing the steps of the stereolithography combined processing method. As shown in FIG. 2, the base plate 51 is placed on the lifting table 12, and the metal powder 4 is applied to the base plate 51 by the blade 14. The metal powder 4 is placed on the elevating table 12 up to the upper end of the wall 13 and leveled almost horizontally by the blade 14. Next, as shown in FIG. 3, the laser light source 31 irradiates the metal powder 4 with laser light, the metal powder 4 is heated and sintered, and the solidified layer 52 in which the metal powder 4 is solidified is formed. . The laser beam is scanned in the shape of the cross-sectional shape of the modeled object, and the solidified layer 52 forms the cross-sectional shape of the modeled object. The scanning shape of the laser light is controlled by the control unit 11. Next, the lifting table 12 is slightly lowered, the metal powder 4 is applied to the solidified layer 52 by the blade 14, the laser light is irradiated to the metal powder 4, the metal powder 4 is sintered, and the next solidified layer 52 is formed. Is done. Application of the metal powder 4, irradiation with laser light, and sintering of the metal powder 4 are repeated, and a plurality of solidified layers 52 are laminated. The blade 14, the laser light source 31, the mirror 32, the lens 33, and the control unit 11 correspond to a stacked unit.

When the predetermined number of solidified layers 52 are laminated, as shown in FIG. 4, the cutting machine 2 performs cutting on the modeling layer 53 formed by laminating a plurality of solidified layers 52. By the cutting process, the modeling layer 53 is processed into a desired shape forming a part of the modeled object. A desired shape to be processed by the modeling layer 53 is determined in advance and stored in the control unit 11. The shape of the modeling layer 53 to be processed is controlled by the control unit 11 controlling the operation of the cutting machine 2. The cutting machine 2 and the control unit 11 correspond to a cutting unit. The formation and lamination of the modeling layer 53 and the cutting process on the modeling layer 53 are repeated, and as shown in FIG. 5, a three-dimensional layered object 54 formed by laminating a plurality of modeling layers 53 is manufactured. The side surface of the modeling layer 53 becomes the surface of the three-dimensional layered object 54.

Detailed explanation about cutting. FIG. 6 is a schematic cross-sectional view showing a state in which a new modeling layer 53 is laminated on a plurality of modeling layers 53. Here, the plurality of stacked modeling layers 53 are referred to as a first modeling layer 531, a second modeling layer 532, a third modeling layer 533, and a fourth modeling layer 534, respectively. A plurality of modeling layers 53 are laminated from the lower layer in the order of the first modeling layer 531, the second modeling layer 532, the third modeling layer 533, and the fourth modeling layer 534. Another modeling layer 53 is laminated below the first modeling layer 531. The first modeling layer 531 is finished in a desired shape for constituting a part of the modeled object. A part of the second modeling layer 532 is finished to a desired shape, and the other part is cut to leave a finishing allowance 55 protruding outward from the desired shape. The portion where the finishing is performed is below the portion where the finishing allowance 55 is left. The third modeling layer 533 is in a state of being cut with the finishing allowance 55 left. The fourth modeling layer 534 is newly formed by stacking the plurality of solidified layers 52 and has not yet been cut.

When the solidified layer 52 is newly laminated on the modeling layer 53, heat for forming the solidified layer 52 is transmitted to the modeling layer 53, and the modeling layer 53 is deformed. For example, the heat-transferred portion contracts. The finishing allowance 55 is provided in the upper modeling layer 53 where heat is easily transmitted in order to cancel the deformation of the modeling layer 53. The thickness d at which the finishing allowance 55 protrudes outward from the desired shape of the modeling layer 53 is large enough to offset the deformation of the modeling layer 53. A thickness d of the finishing allowance 55 is, for example, 0.035 mm.

FIG. 7 is a flowchart showing a procedure of a cutting process according to the first embodiment. The manufacturing apparatus 1 uses the second cutting tool 22 to perform a rough finishing process of cutting the modeling layer 53 while leaving the finishing allowance 55 (S11). Next, the manufacturing apparatus 1 performs the removal process which removes the metal powder 4 from the circumference | surroundings of the modeling layer 53 which should be processed using the rod-shaped tool 23 (S12). Next, the manufacturing apparatus 1 uses the first cutting tool 21 to perform a finishing process in which the finishing allowance 55 is cut off and the modeling layer 53 is cut into a desired shape (S13). The process of S13 corresponds to the finishing part, and the process of S12 corresponds to the removal part.

FIG. 8 is a schematic cross-sectional view showing the rough finishing process. The cutting machine 2 performs processing using the second cutting tool 22. The second cutting tool 22 is a substantially cylindrical end mill. Although omitted in FIG. 8, the second cutting tool 22 has a cutting blade on the side surface, and a groove is formed. The 2nd cutting tool 22 rotates centering on a central axis, and cuts what contacts a side. The cutting machine 2 rotates the second cutting tool 22 to bring the side surface of the second cutting tool 22 into contact with the side surface of the modeling layer 53 to cut the modeling layer 53. At this time, as shown in FIG. 8, the second modeling layer 532, the third modeling layer 533, and the fourth modeling layer 534 are processed to leave the finishing allowance 55. The metal powder 4 exists around the modeling layer 53, and the second cutting tool 22 performs the cutting process while scraping the metal powder 4.

FIG. 9 is a schematic cross-sectional view showing the removal process according to the first embodiment. The cutting machine 2 changes the tool from the second cutting tool 22 to the rod-shaped tool 23. The rod-shaped tool 23 is a substantially cylindrical tool. For example, the rod-shaped tool 23 is a cutting tool such as a drill or an end mill. The diameter a of the rod-shaped tool 23 is larger than the maximum diameter of the first cutting tool 21. The cutting machine 2 rotates the rod-shaped tool 23 with the central axis as the center of rotation, and inserts it into the metal powder 4 around the modeling layer 53. At this time, the cutting machine 2 slightly separates the bar-shaped tool 23 from the side surface of the modeling layer 53 processed by the rough finishing process. Further, the cutting machine 2 inserts the rod-shaped tool 23 to a position deeper than the deepest position of the first cutting tool 21 in the subsequent finishing process.

The cutting machine 2 moves the rod-shaped tool 23 inserted into the metal powder 4 around the modeling layer 53 along the side surface of the modeling layer 53. At this time, the cutting machine 2 moves the rod-shaped tool 23 while being separated from the side surface of the modeling layer 53 by a predetermined distance. The metal powder 4 is pushed away by the moving rod-shaped tool 23, and the metal powder 4 is removed from the periphery of the modeling layer 53. The metal powder 4 that has been in contact with the side surface of the modeling layer 53 to be subjected to the finishing process is also removed. The predetermined distance for separating the bar-shaped tool 23 from the side surface of the modeling layer 53 is such a distance that the metal powder 4 is removed from the side surface of the modeling layer 53 as much as possible. This distance is, for example, 0.05 mm.

10 and 11 are schematic cross-sectional views showing the finishing process according to the first embodiment. The cutting machine 2 changes the tool from the rod-shaped tool 23 to the first cutting tool 21. The first cutting tool 21 is an end mill and has a substantially cylindrical shape as a whole. The first cutting tool 21 includes a columnar part 212 and a cutting part 211 connected to the tip of the columnar part 212. Although omitted in the drawing, the cutting portion 211 has a cutting blade on its side surface and has a groove. The columnar portion 212 does not have a cutting blade. Further, the maximum diameter of the cutting part 211 exceeds the diameter of the columnar part 212. For this reason, the side surface of the cutting part 211 protrudes from the side surface of the columnar part 212. Further, as described above, the diameter a of the rod-shaped tool 23 is larger than the maximum diameter b of the first cutting tool 21. The first cutting tool 21 rotates with the cutting portion 211 on the lower side and the central axis of the columnar portion 212 as the rotation center, and cuts the one that contacts the side surface of the cutting portion 211.

The cutting machine 2 rotates the first cutting tool 21, inserts the first cutting tool 21 around the modeling layer 53, contacts the side surface of the cutting part 211 with the side surface of the modeling layer 53, and cuts the modeling layer 53. Process. At this time, the cutting machine 2 scrapes off a part of the finishing allowance 55 in the third modeling layer 533 and performs a process of finishing a part of the third modeling layer 533 into a desired shape. FIG. 10 shows a state where the finishing allowance 55 in the third modeling layer 533 is scraped off. The cutting machine 2 lowers the first cutting tool 21 while continuing the cutting process, so that the finishing allowance 55 in the second modeling layer 532 is scraped off and the second modeling layer 532 is processed into a desired shape. FIG. 11 shows a state in which the finishing allowance 55 in the second modeling layer 532 is scraped off, and the first cutting tool 21 is at a substantially deepest position. By this finishing process, the second modeling layer 532 and a part of the third modeling layer 533 are finished in a desired shape. The other portions of the third modeling layer 533 and the finishing allowance 55 in the fourth modeling layer 534 are left without being cut. The portion where the finishing allowance 55 is left in the third modeling layer 533 is above the portion where the finishing is performed. Since the side surface of the cutting portion 211 protrudes from the side surface of the columnar portion 212, it is possible to perform a process of removing the finishing allowance 55 in the lower modeling layer 53 while leaving the finishing allowance 55 in the upper modeling layer 53. After the finishing process is finished, the cutting process is finished. After the cutting process is completed, the solidified layer 52 is further formed and laminated, and when the next cutting process is executed, the process starts again from the state shown in FIG.

Since the metal powder 4 is removed from the periphery of the modeling layer 53 in the removal process, as shown in FIGS. 10 and 11, in the finishing process, the first cutting tool 21 is inserted into the space from which the metal powder 4 has been removed. The Since the removal process is performed using the rod-shaped tool 23 whose diameter a exceeds the maximum diameter b of the first cutting tool 21, the metal powder 4 is removed from the range where the inserted first cutting tool 21 comes into contact. In the removal process, since the rod-shaped tool 23 is inserted to a position deeper than the deepest position of the first cutting tool 21 in the finishing process, the metal powder 4 is removed even at the deepest position of the first cutting tool 21. Yes. For this reason, in a finishing process, the 1st cutting tool 21 moves in the space from which the metal powder 4 was removed. The possibility that the first cutting tool 21 contacts the metal powder 4 during the finishing process is low, and the metal powder 4 that has contacted the first cutting tool 21 is suppressed from roughening the side surface of the modeling layer 53. Therefore, it is prevented that the metal powder 4 roughens the side surface of the modeling layer 53, so that the surface of the three-dimensional layered object is not uneven, and the generation of the surface unevenness of the three-dimensional layered object is suppressed. Even when the number of the solidified layers 52 constituting the modeling layer 53, that is, the number of the plurality of solidified layers 52 that are collectively subjected to the cutting process, is increased, the occurrence of unevenness on the surface of the three-dimensional layered object can be suppressed. Therefore, it is possible to manufacture a high-quality three-dimensional layered object with less surface irregularities while avoiding an increase in manufacturing time.

The example which verified the manufacturing method of the three-dimensional layered object concerning this embodiment is explained. A three-dimensional layered object having the same shape was manufactured by the manufacturing method according to this embodiment and the conventional manufacturing method. The conventional manufacturing method is a method that does not include a removal step of removing the metal powder using the rod-shaped tool 23. Other conditions are the same. FIG. 12 is a view showing a photograph of a three-dimensional layered object manufactured by the manufacturing method according to Embodiment 1 and the conventional manufacturing method. The three-dimensional layered object manufactured by the conventional manufacturing method has irregularities on the surface. The generated unevenness has a striped pattern that intersects the direction in which the solidified layer 52 is laminated. On the other hand, the three-dimensional layered object manufactured by the manufacturing method according to the present embodiment has clearly reduced surface irregularities. As a result of comparing the surface roughness between the two, Ra, which indicates the average height of the unevenness, was 0.342 μm in the conventional manufacturing method, whereas it was 0.222 μm in the present embodiment. In addition, Rz, which is the maximum value of the height difference of the unevenness, was 2.906 μm in the conventional manufacturing method, whereas it was 1.436 μm in the present embodiment. The three-dimensional layered object manufactured by the conventional manufacturing method has a surface roughness of 1.5 times or more compared to the three-dimensional layered object manufactured by the manufacturing method according to this embodiment. That is, it is clear that a high-quality three-dimensional layered object having few surface irregularities can be manufactured by this embodiment.

(Embodiment 2)
The configuration of the three-dimensional layered object manufacturing apparatus 1 according to the second embodiment is the same as that of the first embodiment. In the second embodiment, the cutting process is different from that of the first embodiment. Of the steps for manufacturing the three-dimensional layered object, steps other than the cutting step are the same as those in the first embodiment.

FIG. 13 is a flowchart showing a procedure of a cutting process according to the second embodiment. The manufacturing apparatus 1 uses the second cutting tool 22 to perform a rough finishing process of cutting the modeling layer 53 while leaving the finishing allowance 55 (S21). Next, the manufacturing apparatus 1 raises the elevating table 12 until the position of the modeling layer 53 that is the object of cutting is higher than the upper end of the wall 13 (S22). The position of the lifting table 12 is controlled by the control unit 11. Next, the manufacturing apparatus 1 performs the removal process which removes a metal powder from the circumference | surroundings of the modeling layer 53 which should be processed using the rod-shaped tool 23 (S23). The process of S22 corresponds to the ascending part, and the process of S23 corresponds to the removal part.

FIG. 14 is a schematic partial cross-sectional view illustrating a partial state of the manufacturing apparatus 1 when performing the removing process according to the second embodiment. From the state for the step of laminating the solidified layer 52 as shown in FIG. 2 and FIG. 3, the position of a part of the three-dimensional layered object 54 being manufactured is higher than the upper end of the wall 13 as shown in FIG. The lift table 12 is raised to the position. FIG. 15 is a schematic cross-sectional view illustrating a removal process according to the second embodiment. The lifting table 12 is raised until at least a part of the modeling layer 53 to be cut is higher than the upper end of the wall 13. For example, the positions of the second modeling layer 532, the third modeling layer 533, and the fourth modeling layer 534 that are the objects of cutting, and the position of a part of the first modeling layer 531 are higher than the upper end of the wall 13. It is desirable to become. Similarly to the first embodiment, the cutting machine 2 rotates the rod-shaped tool 23 and inserts it into the metal powder 4 around the modeling layer 53, and around the modeling layer 53 along the side surface of the modeling layer 53. Move. At this time, the cutting machine 2 inserts the rod-shaped tool 23 to a position deeper than the deepest position of the first cutting tool 21 in the subsequent finishing process.

The metal powder 4 around the modeling layer 53 at a position higher than the upper end of the wall 13 can overflow to the outside beyond the upper end of the wall 13. When the rod-shaped tool 23 moves around the modeling layer 53, the metal powder 4 pushed away by the rod-shaped tool 23 is discharged outside beyond the upper end of the wall 13. For this reason, the amount of the metal powder 4 that cannot be removed from the surroundings of the modeling layer 53 in the removal step or the amount of the metal powder 4 that returns to the surroundings of the modeling layer 53 after being removed is reduced, and the effect from the periphery of the modeling layer 53 is reduced. Thus, the metal powder 4 is removed.

Next, the manufacturing apparatus 1 uses the first cutting tool 21 to cut off the finishing allowance 55 and perform a finishing process of cutting the modeling layer 53 into a desired shape (S24). FIG. 16 is a schematic cross-sectional view illustrating a finishing process according to the second embodiment. The cutting machine 2 rotates the first cutting tool 21, inserts the first cutting tool 21 around the modeling layer 53, contacts the side surface of the cutting part 211 with the side surface of the modeling layer 53, and cuts the modeling layer 53. Process. At this time, the cutting machine 2 scrapes off a part of the finishing allowance 55 in the third modeling layer 533, finishes a part of the third modeling layer 533 into a desired shape, and sets the finishing allowance 55 in the second modeling layer 532. It cuts and performs the process which finishes the 2nd modeling layer 532 in a desired shape. The process of S24 corresponds to the finishing part.

After the finishing process is completed, the manufacturing apparatus 1 lowers the elevating table 12 until the position of the three-dimensional layered object 54 being manufactured is lower than the upper end of the wall 13 (S25). The process ends. After the cutting process is completed, the metal powder 4 is applied to the three-dimensional layered object 54 being manufactured by the blade 14, and the solidified layer 52 is formed and laminated.

In the present embodiment, since the metal powder 4 is effectively removed from the periphery of the modeling layer 53 in the removal process, the first cutting tool 21 is a metal powder during the finishing process as shown in FIG. 4 becomes difficult to contact. It is unlikely that the metal powder 4 in contact with the first cutting tool 21 roughens the side surface of the modeling layer 53, and the surface of the three-dimensional layered object is uneven because the metal powder 4 roughens the side surface of the modeling layer 53. Is prevented from occurring. Therefore, it is possible to manufacture a high-quality three-dimensional layered object with less surface irregularities while avoiding an increase in manufacturing time.

Note that the manufacturing apparatus 1 may execute the processes of S21 and S22 in the reverse order. That is, the manufacturing apparatus 1 may perform rough finishing after raising the lifting table 12. Moreover, the manufacturing apparatus 1 may perform the process of S24 and S25 in reverse order. That is, the manufacturing apparatus 1 may perform finishing after lowering the lifting table 12. Moreover, the manufacturing apparatus 1 may perform a removal process by raising the raising / lowering table 12. FIG. When the raising / lowering table 12 is raised until the position of the modeling layer 53 to be cut is higher than the upper end of the wall 13, the metal powder 4 collapses and passes the upper end of the wall 13 to the outside. Overflows. Therefore, the manufacturing apparatus 1 can remove the metal powder 4 from the surroundings of the modeling layer 53 that is the object of cutting only by raising the elevating table 12.

(Embodiment 3)
FIG. 17 is a schematic cross-sectional view illustrating a partial configuration of the three-dimensional layered object manufacturing apparatus 1 according to the third embodiment. A discharge hole 131 for discharging the metal powder 4 is formed in the wall 13. The discharge hole 131 corresponds to the discharge portion. The step of forming and stacking the solidified layer 52 is performed in a state where the mounting surface 121 of the lifting table 12 is at a position higher than the discharge hole 131. Other configurations of the manufacturing apparatus 1 are the same as those in the first embodiment. In the third embodiment, the cutting process is different from the first embodiment. Of the steps for manufacturing the three-dimensional layered object, steps other than the cutting step are the same as those in the first embodiment.

FIG. 18 is a flowchart showing a procedure of a cutting process according to the third embodiment. The manufacturing apparatus 1 uses the second cutting tool 22 to perform a rough finishing process of cutting the modeling layer 53 while leaving the finishing allowance 55 (S31). Next, the manufacturing apparatus 1 lowers the lifting table 12 until the position of the mounting surface 121 of the lifting table 12 is lower than at least a part of the discharge hole 131 (S32). The position of the lifting table 12 is controlled by the control unit 11. The process of S32 corresponds to the descending part.

FIG. 19 is a schematic partial cross-sectional view showing a state where the elevating table 12 is lowered. As shown in FIG. 17, from the state for the step of laminating the solidified layer 52, ascending and descending until the mounting surface 121 of the lifting table 12 is at a position lower than at least a part of the discharge hole 131 as shown in FIG. The table 12 descends. In this state, a part of the metal powder 4 above the mounting surface 121 passes through the discharge hole 131 and is discharged to the outside. It is assumed that the lifting table 12 is not lowered until the discharge hole 131 is completely higher than the metal powder 4 and the metal powder 4 cannot be discharged.

After a certain amount of the metal powder 4 is discharged, the manufacturing apparatus 1 raises the lifting table 12 (S33). At this time, the manufacturing apparatus 1 raises the lifting table 12 from the position shown in FIG. 19 to a predetermined position where the placement surface 121 is higher than the discharge hole 131. For example, the elevating table 12 is raised so that the position of the placement surface 121 is the same as the position shown in FIG. Next, the manufacturing apparatus 1 performs the removal process which removes the metal powder 4 from the circumference | surroundings of the modeling layer 53 which should be processed using the rod-shaped tool 23 (S34). The process of S33 corresponds to the second ascending part, and the process of S34 corresponds to the removal part.

The cutting machine 2 rotates the rod-shaped tool 23, inserts it into the metal powder 4 around the modeling layer 53 that is the object of cutting, and surrounds the modeling layer 53 along the side surface of the modeling layer 53. Move. At this time, the cutting machine 2 inserts the rod-shaped tool 23 to a position deeper than the deepest position of the first cutting tool 21 in the subsequent finishing process. The metal powder 4 is pushed away by the moving rod-shaped tool 23, and the metal powder 4 is removed from the periphery of the modeling layer 53. As a result of part of the metal powder 4 being discharged in S32, the amount of the metal powder 4 is decreasing. For this reason, in order to remove the metal powder 4 from the circumference | surroundings of the modeling layer 53, the quantity of the metal powder 4 which the rod-shaped tool 23 should push away reduces. Further, the amount of the metal powder 4 that cannot be removed from the surroundings of the modeling layer 53 in the removing process or the amount of the metal powder 4 that returns to the surroundings of the modeling layer 53 after being removed decreases. Therefore, the metal powder 4 is effectively removed from the periphery of the modeling layer 53.

Next, the manufacturing apparatus 1 uses the first cutting tool 21 to perform the finishing process of cutting the finishing allowance 55 and cutting the modeling layer 53 into a desired shape (S35). The cutting machine 2 rotates the first cutting tool 21, inserts the first cutting tool 21 around the modeling layer 53, contacts the side surface of the cutting part 211 with the side surface of the modeling layer 53, and cuts the modeling layer 53. Process. At this time, the cutting machine 2 cuts off a part of the finishing allowance 55 and performs a process of finishing a part of the modeling layer 53 into a desired shape. The process of S35 corresponds to the finishing part. After the finishing process is finished, the manufacturing apparatus 1 finishes the cutting process. After the cutting process is completed, the metal powder 4 is applied to the three-dimensional layered object 54 being manufactured by the blade 14, and the solidified layer 52 is formed and laminated.

In the present embodiment, since the metal powder 4 is effectively removed from the periphery of the modeling layer 53 in the removal process, the second process is performed during the finishing process as in the case of the second embodiment shown in FIG. 1 It becomes difficult for the cutting tool 21 to contact the metal powder 4. It is unlikely that the metal powder 4 in contact with the first cutting tool 21 will roughen the modeling layer 53, and unevenness is generated on the surface of the three-dimensional layered object because the metal powder 4 roughens the side surface of the modeling layer 53. It is prevented. Therefore, it is possible to manufacture a high-quality three-dimensional layered object with less surface irregularities while avoiding an increase in manufacturing time.

Note that the manufacturing apparatus 1 may execute the process of S31 after the process of S33. That is, the manufacturing apparatus 1 may perform rough finishing after discharging a part of the metal powder 4. Moreover, the manufacturing apparatus 1 may perform a removal process in the state which lowered the raising / lowering table 12, and may perform rough finishing or finishing in the state which lowered the raising / lowering table 12. FIG. Moreover, the manufacturing apparatus 1 may perform the removal process by lowering the lifting table 12. When the lifting table 12 is lowered until the placement surface 121 is at a position lower than at least a part of the discharge hole 131, the metal powder 4 is naturally discharged outside through the discharge hole 131. Therefore, the manufacturing apparatus 1 can remove the metal powder 4 from the periphery of the modeling layer 53 that is the object of cutting by simply lowering the elevating table 12. Moreover, in this embodiment, although the discharge part formed in the wall 13 showed the example which is the discharge hole 131, the form other than the discharge hole 131 may be sufficient as a discharge part. For example, the discharge part may be the lower end of the wall 13.

In the first to third embodiments, the solidified layer is formed by sintering the metal powder 4. However, the three-dimensional layered object manufacturing apparatus 1 melts and solidifies the metal powder 4. In this case, the solidified layer 52 may be formed. In the first to third embodiments, the laser beam is used as the energy beam. However, the manufacturing apparatus 1 may use an energy beam other than the laser beam. In the first to third embodiments, the metal powder 4 is used as the material powder. However, the manufacturing apparatus 1 may use a material powder other than the metal powder such as a resin powder.

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus 11 Control part 12 Lifting table 121 Mounting surface 13 Wall 131 Discharge hole (discharge part)
2 Cutting Machine 21 First Cutting Tool 22 Second Cutting Tool 23 Bar Tool 31 Laser Light Source 4 Metal Powder (Material Powder)
52 Solidified layer 53 Modeling layer 54 Three-dimensional layered object

Claims

A three-dimensional layered object is formed by forming a solidified layer obtained by solidifying the material powder by irradiating the material powder with an energy beam, laminating the solidified layer, and cutting the plurality of laminated solidified layers. In the method of manufacturing
The cutting process is
A finishing step of cutting at least a part of the plurality of solidified layers into a required shape by a rotating first cutting tool;
Before the finishing step, a rod-shaped tool having a diameter larger than that of the first cutting tool is moved around the plurality of solidified layers along the side surfaces of the plurality of solidified layers, so that the plurality of solidified layers are formed. A removing step of removing the material powder from the surroundings. A method for producing a three-dimensional layered object.
The method of manufacturing a three-dimensional layered object according to claim 1, wherein the removing step removes the material powder to a position deeper than a deepest position of the first cutting tool in the finishing step.
The cutting process includes
Before the removing step, further comprising a rough finishing step of cutting at least a part of the plurality of solidified layers by a second cutting tool;
The finishing step cuts at least a part of the portion already cut by the rough finishing step,
3. The three-dimensional additive manufacturing according to claim 1, wherein the removing step moves the bar-shaped tool at a predetermined distance from the side surfaces of the solidified layers cut by the rough finishing step. Manufacturing method.
A lifting table on which the material powder is placed and the plurality of solidified layers are stacked;
Using the wall surrounding the lifting table to hold the material powder on the lifting table,
The removing step is performed in a state in which the lifting table is raised until a position of a portion to be cut of the plurality of solidified layers is higher than an upper end of the wall. Item 4. The method for producing a three-dimensional layered object according to any one of Items 1 to 3.
A lifting table on which the material powder is placed and the plurality of solidified layers are stacked;
Using the wall surrounding the lifting table to hold the material powder on the lifting table,
The wall is formed with a discharge portion for discharging the material powder,
The step of forming and laminating the solidified layer is performed in a state where the mounting surface of the lifting table is at a higher position than the discharge unit,
The cutting process includes
Lowering the elevating table until the position of the placement surface is lower than a part of the discharge portion;
A step of raising the lifting table until the position of the placement surface is higher than the discharge unit,
The method of manufacturing a three-dimensional layered object according to any one of claims 1 to 3, wherein the removing step is performed after a step of lowering and raising the lifting table.
Forming a solidified layer obtained by solidifying the material powder by irradiating the material powder with an energy beam, and laminating the solidified layer; and a cutting unit performing cutting on the plurality of solidified layers. In an apparatus for producing a three-dimensional layered object,
The cutting portion is
A finishing portion that cuts at least a part of the plurality of solidified layers into a required shape by a rotating cutting tool;
Before cutting by the finishing portion, a plurality of solidified layers are moved by moving a rod-shaped tool having a diameter larger than that of the cutting tool around the plurality of solidified layers along side surfaces of the plurality of solidified layers. And a removing unit that removes the material powder from the periphery of the three-dimensional layered object manufacturing apparatus.
A lifting table on which the material powder is placed and the plurality of solidified layers are stacked;
A wall surrounding the lifting table to hold the material powder on the lifting table;
The cutting portion is
In the operation by the removing unit, the moving table further includes a lifting unit that lifts the lifting table until the position of the portion to be cut of the plurality of solidified layers is higher than the upper end of the wall. The manufacturing apparatus of the three-dimensional layered object according to claim 6.
A lifting table on which the material powder is placed and the plurality of solidified layers are stacked;
A wall surrounding the lifting table to hold the material powder on the lifting table;
The wall is formed with a discharge portion for discharging the material powder,
The stacking unit forms and stacks the solidified layer in a state where the mounting surface of the lifting table is higher than the discharge unit,
The cutting portion is
A lowering part that lowers the lifting table until the position of the placement surface is lower than a part of the discharge part;
A second raising part that raises the lifting table until the position of the placement surface is higher than the discharge part;
The apparatus for manufacturing a three-dimensional layered object according to claim 6, wherein the removing unit performs work after the descending unit and the second ascending unit are operated.