Shaping area limiting unit and additive manufacturing apparatus including the same

Abstract

This invention provides a shaping area limiting unit and a stacking shaping apparatus including the same, which facilitates the fabrication of small three-dimensional shapes using material powders different from those used in conventional methods. Furthermore, the shaping area limiting unit reduces the workload associated with cleaning operations during material changes. The shaping area limiting unit for the stacking shaping apparatus includes: a movable side unit fixed to a shaping platform; and a non-movable side unit mounted on a base. The movable side unit includes a first anti-scattering frame protruding upwards. The non-movable side unit includes: a flat plate covering the first shaping area outside the opening to form a second shaping area; and a second anti-scattering frame protruding downwards from the outer periphery of the opening. The first anti-scattering frame surrounds the second anti-scattering frame at intervals.

Description

Technical Field

[0001] The present invention relates to a shaping area limiting unit and a layered shaping device including the shaping area limiting unit. Background Technology

[0002] A lamination molding apparatus for powder fusion bonding disperses material powder in the shaping region (the area where the desired three-dimensional shape can be formed) to form a material layer. The apparatus then irradiates the material layer with a laser or electron beam, causing the powder to sinter or melt and form a solidified layer. The lamination molding apparatus repeatedly forms material powder layers and solidified layers to create the desired three-dimensional shape.

[0003] There are various types of powder materials used in lamination forming. Sometimes, a single lamination forming apparatus uses multiple materials, requiring material changeover procedures. During material changeovers, the lamination forming apparatus must be cleaned to remove any existing material present inside.

[0004] The lamination forming apparatus disclosed in US Patent 10,569,331 is configured to recover surplus material generated during manufacturing and, after removing inclusions, resupply it to the lamination forming apparatus body. Hereinafter, the apparatus for recovering and resupplying surplus material will be referred to as the material recycling unit. During material replacement, not only the lamination forming apparatus body but also the material recycling unit must be cleaned.

[0005] The lamination forming apparatus disclosed in U.S. Patent Publication US2022 / 0118524 ​​allows for the separability of material recycling units from the lamination forming apparatus body. By preparing material recycling units for each type of material powder, cleaning of the material recycling units is unnecessary during material replacement. This reduces the time required for material replacement. Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] Sometimes, different material powders are used experimentally to create small three-dimensional shapes. For example, when exploring the use of new material powders, the powders are used to create test pieces, and the properties of the test pieces are measured, or laser or electron beam irradiation conditions are selected.

[0008] Traditional layered molding devices are designed for the largest possible shapes, thus requiring a relatively large amount of material powder. For example, during the formation of material layers, the material powder is often distributed beyond the actual required area. Therefore, even when manufacturing small three-dimensional shapes, a certain amount of material powder must be prepared.

[0009] Furthermore, as mentioned earlier, cleaning is required during material replacement. As disclosed in US Patent 10,569,331, it is known to prepare material recycling units for each material to reduce the effort required for material replacement. However, since the material powder is being used for testing purposes, preparing dedicated material recycling units would increase costs.

[0010] This invention was made in view of this situation, providing a shaping region limiting unit and a stacking shaping device including the shaping region limiting unit, suitable for simply stacking small three-dimensional shapes such as shaping test pieces using a small amount of material powder.

[0011] [Technical means to solve the problem]

[0012] According to this application, a shaping area limiting unit is provided, which is a shaping area limiting unit for a stacked shaping device. The stacked shaping device includes: a base platform having a region capable of forming a three-dimensional shape, namely a first shaping region; and a shaping platform disposed in the first shaping region, configured to move vertically, and having a fixed base plate. The stacked shaping device alternately and repeatedly forms a material layer containing material powder and a cured layer. The shaping area limiting unit includes: a movable side unit fixed to the shaping platform; and a non-movable side unit. A movable side unit is placed on the base platform. The movable side unit includes a first anti-scattering frame, which is a hollow frame protruding upwards. The non-movable side unit includes: a plate having an opening and placed on the base platform, the portion outside the opening covering the first shaped area to form a second shaped area smaller than the first shaped area; and a second anti-scattering frame, which is a hollow frame protruding downwards from the outer periphery of the opening, the first anti-scattering frame surrounding the second anti-scattering frame at intervals.

[0013] [The effects of the invention]

[0014] The shaping area restriction unit of this invention facilitates the fabrication of small three-dimensional shapes using material powders that differ from conventional methods. Furthermore, the shaping area restriction unit reduces the workload associated with cleaning operations during material changes. Attached Figure Description

[0015] Figure 1 It is a schematic structural diagram of a stacked shaping device with shaping area restriction units installed.

[0016] Figure 2 It is a schematic structural diagram of a stacked shaping device with shaping area restriction units installed.

[0017] Figure 3This is a front view of the recoating head and the recoating head drive mechanism used in the second shaping area.

[0018] Figure 4 This is a three-dimensional view of the second shaping area using the repainting head.

[0019] Figure 5 This is a three-dimensional view of the second shaping area using the repainting head.

[0020] Figure 6 yes Figure 4 DD cross-section view.

[0021] Figure 7 This is a side view of the second shaping area viewed from the direction of arrow B, using the repainting head.

[0022] Figure 8 This is a top view of the base platform with the shaping area restriction unit installed.

[0023] Figure 9 This is a top view of the non-movable side unit.

[0024] Figure 10 This is a cross-sectional view of the non-movable side unit.

[0025] Figure 11 This is a top view of the movable side unit.

[0026] Figure 12 This is a cross-sectional view of the movable side unit.

[0027] Figure 13 yes Figure 8 EE cross-section diagram.

[0028] Figure 14 yes Figure 13 Enlarged F-image.

[0029] Figure 15 This indicates the state of material powder accumulating in the first anti-scattering frame.

[0030] Figure 16 This is a schematic structural diagram of the stacked shaping device 100 with the shaping area restriction unit disassembled.

[0031] Figure 17 It is a three-dimensional view of the first shaping area using the repainting head.

[0032] Figure 18 This is a top view of the first shaping area using the repainting machine head.

[0033] Figure 19 Examples of shape area restriction units with different specifications. Detailed Implementation

[0034] Hereinafter, embodiments of the present invention will be described using the accompanying drawings. The various features shown in the embodiments described below can be combined with each other. Figures 1 to 15 The illustration shows a stacking device or its components when using the shaping area restriction unit 8 for stacking shaping. Figures 16 to 18 The illustration shows a stacking device or its components when stacking is performed without using the shaping area restriction unit 8.

[0035] The stacked forming apparatus 100 of this embodiment repeatedly forms a material layer 6 containing material powder M and a cured layer to manufacture the desired three-dimensional object K. The stacked forming apparatus 100, as described above... Figure 1 , Figure 2 as well as Figure 16 As shown, the system includes a chamber 1, an irradiation device 13, an inactive gas supply device 15, a smoke collector 19, a shaping platform drive mechanism 52, a recoating head 31 for the first shaping area, a base platform 4, a material recycling unit 40, a shaping platform 5, a recoating head drive mechanism 51, a material supply unit 60, and a shaping area restriction unit 8. As described later, some components are sometimes disassembled or unused. The base platform 4 has a region capable of forming a three-dimensional shape K, namely a first shaping area R and a second shaping area Rs. The first shaping area R contains the second shaping area Rs. That is, the second shaping area Rs is a part of the first shaping area R and is located within the first shaping area R. The material recycling unit 40 and the material supply unit 60 constitute the material reuse unit in this embodiment.

[0036] Figure 16 This illustrates the state of the lamination apparatus 100 when performing lamination using the first shaping area R. Typically, the first shaping area R is used when continuously laminating shaped articles. At this time, a material recycling unit (material recovery unit 40) and a material supply unit 60, along with a recoating head 31 for the first shaping area, are used. Specifically, firstly, the recoating head 31 for the first shaping area moves along a first horizontal direction (arrow B direction) via a recoating head drive mechanism 51, forming a material layer 6 on a base plate 33 disposed on a shaping platform 5. Then, an irradiation device 13 irradiates the material layer 6 with laser L to form a cured layer. The shaping platform 5 descends one layer, and the same process is repeated to form the material layer 6 on the cured layer, and the material layer 6 is irradiated with laser L to form a cured layer. Thus, the formation of the material layer 6 and the formation of the cured layer are alternately and repeatedly performed to manufacture a three-dimensional object K.

[0037] During the layering process, uncured material powder M, i.e., residual material, is generated. This residual material may contain inclusions, such as sputtering particles that flew out during the formation of the cured layer. Cutting chips may also be included as inclusions during the machining of the cured layer. The residual material is pushed out by the recoating head 31 from the first forming area and discharged from the opening formed in the base platform 4, i.e., the material recovery port 27b. Furthermore, a material recovery port 27a is formed at the lower part of the material holding wall 26 surrounding the forming platform 5. After the three-dimensional object K is manufactured, the residual material is discharged from the material recovery port 27a by lowering the forming platform 5. Alternatively, the residual material can be dropped to the material recovery port 27b using a brush or similar means after the forming platform 5 is raised. The residual material can also be discharged using other components such as a suction nozzle. The discharged residual material is guided by the chute 29 and collected in the hopper 30. After removing inclusions by the material recovery unit 40, it is sent to the material supply unit 60. The material supply unit 60 supplies unused material powder M or material powder M from which inclusions have been removed by the material recycling unit 40 to the material box 311 of the recoating head 31 in the first shaping area. The above process is repeated to continuously laminate and shape the three-dimensional object K.

[0038] Figure 1 as well as Figure 2 This describes the stacking forming apparatus 100 when only the second forming area Rs is used for stacking forming. Typically, the second forming area Rs is used when stacking small three-dimensional objects K, such as test pieces, using a material powder M that is different from the usual material powder for testing purposes. At this time, the forming area limiting unit 8 is used, and on the other hand, the material powder M is not supplied from the material supply unit 60, and the remaining material is not recovered from the material recovery port 27a and the material recovery port 27b. By not using the material powder M recovery system and the material supply system that include the material recycling unit 40 and the material supply unit 60, the mixing of different types of materials, typically mass production material powder M and test material powder M, is prevented. As a result, the workload of switching between the two types of material powder M and cleaning is reduced. When the material recycling unit is detachable from the chamber 1, the material recycling unit can be disassembled when the forming area limiting unit 8 is used.

[0039] Chamber 1 covers the areas forming the three-dimensional object K, namely the first shaping area R and the second shaping area Rs. Chamber 1 is composed of multiple side plates and a top plate, with an openable and closable door on one side plate. A glove box may also be provided on the door. Chamber 1 is filled with a specified concentration of inactive gas. In this specification, inactive gas refers to a gas that does not substantially react with the material powder M, such as nitrogen, argon, or helium. The material powder M is, for example, a metal powder.

[0040] An irradiation device 13 is disposed above the chamber 1. The irradiation device 13 irradiates a predetermined portion of the material layer 6 formed on the first shaping region R or the second shaping region Rs with laser L, causing the material powder M at the irradiated location to melt or sinter to form a solidified layer. More specifically, the irradiation device 13 of this embodiment includes a light source that outputs laser L and a scanning device that scans laser L. The scanning device is, for example, a galvanometer scanner with an X-axis galvanometer lens and a Y-axis galvanometer lens. Laser L is, for example, a CO2 laser, a fiber laser, or a yttrium aluminum garnet (YAG) laser. Laser L irradiated from the irradiation device 13 irradiates the material layer 6 through a window provided on the upper plate of the chamber 1. The irradiation device 13 may also be a device that irradiates the material layer 6 with an electron beam to form a solidified layer. For example, the irradiation device 13 may also include the following components: a cathode electrode that emits electrons; an anode electrode that collects and accelerates electrons; a solenoid that forms a magnetic field to focus the direction of the electron beam into one direction; and a collector electrode that is electrically connected to the material layer that is the irradiated object and applies a voltage between it and the cathode electrode.

[0041] The cutting device may also be located within the chamber 1. The cutting device cuts the surface or excess portion of the cured layer. The cutting device may include, for example, a machining head that is movable within the chamber 1; and a spindle located on the machining head that grips and rotates the cutting tool.

[0042] like Figure 1 , Figure 2 as well as Figure 16 As shown, in chamber 1, an inert gas supply device 15 and a smoke collector 19 are connected. The inert gas supply device 15 is, for example, an inert gas generating device that generates inert gas from air, or a gas cylinder for storing inert gas. The inert gas supply device 15 supplies inert gas of a predetermined concentration to chamber 1. The smoke collector 19 is an electrostatic precipitator or filter that removes smoke from the inert gas. Smoke is generated during the formation of the solidified layer. The inert gas containing smoke discharged from chamber 1 is sent to the smoke collector 19. The inert gas with smoke removed in the smoke collector 19 is returned to chamber 1. Through this structure, the inert gas is reused.

[0043] The location and number of the supply and exhaust ports for the inactive gas are not limited. For example, the supply and exhaust ports can be formed on the side plate or top plate of chamber 1, or on the constituent elements disposed within chamber 1. The attached figures do not show the actual location and number of the supply and exhaust ports.

[0044] The contamination prevention component 17 is disposed within the chamber 1 in a manner that surrounds the window. The contamination prevention component 17 has a cylindrical shape, stores the inactive gas supplied from the inactive gas supply device 15 inside, and discharges downwards. This prevents smoke from adhering to the window.

[0045] As a material recycling unit that automatically supplies material powder M into the interior of chamber 1, specifically to the recoating head 31 for the first shaping area, and recovers any remaining material, a material supply unit 60 and a material recycling unit 40 are provided. The material supply unit 60 and the material recycling unit 40 are not used when only the second shaping area Rs is used, i.e., when the shaping area restriction unit 8 is used. Hereinafter, an example of the material recycling unit will be described, but the material recycling unit is not limited to the following structure. The material recycling unit is at least composed of a sieve for removing inclusions from the material powder M discharged from chamber 1, and a material conveying device for conveying the material powder M.

[0046] The material supply unit 60 includes a main duct 71, an intermediate duct 69, and an intermediate duct stop 70. The main duct 71 is located on the upper plate of the chamber 1. The intermediate duct 69 is located below the main duct 71. The outlet of the intermediate duct 69, i.e., the outlet 69a, is opened and closed by one or more intermediate duct stop 70s. When using the shaping area restriction unit 8, the outlet 69a is always closed by the intermediate duct stop 70. The material powder M contained in the material box 46 is supplied to the main duct 71 and then supplied from the outlet 69a of the intermediate duct to the recoating head 31 for the first shaping area.

[0047] The material recycling unit 40 includes a recycling conveying device 41, an inclusion removal device 43, a material bin 46, a drying device 47, a supply conveying device 48, and a vacuum pump 49. The recycling conveying device 41 and the supply conveying device 48 are so-called hopper loader machines, connected to the vacuum pump 49 via a three-way valve. In this embodiment, the vacuum pump 49 is shared by the recycling conveying device 41 and the supply conveying device 48, but separate vacuum pumps 49 may also be provided. By operating the vacuum pump 49, a negative pressure is generated within the recycling conveying device 41 or the supply conveying device 48 to convey the material powder M. The inclusion removal device 43 includes, for example, a sieve. After removing inclusions from the remaining material fed from the hopper 30 by the recycling conveying device 41, the inclusion removal device 43 sends the material to the material bin 46. The material bin 46 contains unused material powder M and used material powder M from which inclusions have been removed. In the material bin 46, a drying device 47, which serves as a heater, is provided for drying the material powder M. The material powder M contained in the material bin 46 is conveyed by the supply conveying device 48 and supplied to the main pipe 71 of the material supply unit 60. During the manufacture of the three-dimensional model K, the material recycling unit 40 and the material supply unit 60 can automatically recycle and resupply the material powder M. After the manufacture of the three-dimensional model K, the material recycling unit 40 recycles the material powder M. At this time, the material recycling unit 40 can also store the material powder M in the material bin 46 after removing impurities from the material powder M recycled via the suction nozzle, etc., using the impurity removal device 43. As mentioned above, the recycling of remaining material from the material recycling port 27a, material recycling port 27b or suction nozzle, and the operation of the material recycling unit 40 and the material supply unit 60 are not performed when the modeling area restriction unit 8 is used.

[0048] The base platform 4 is a frame disposed within the chamber 1, having a first shaping region R and a second shaping region Rs. The base platform 4 houses a shaping platform 5, a material holding wall 26, and a hopper 30. The first shaping region R is typically used in the case of continuously stacking shaped articles. The second shaping region Rs is typically used in the case of stacking shaped test pieces for purposes such as evaluating new material powders M. The second shaping region Rs is part of the first shaping region R and is formed within the first shaping region R.

[0049] A shaping platform 5 is disposed in a first shaping region R and a second shaping region Rs. The shaping platform 5 can be moved in the vertical direction (direction of arrow A) by a shaping platform drive mechanism 52. The shaping platform drive mechanism 52 is configured to include any actuator, such as a motor and a ball screw. When performing layered shaping using the second shaping region Rs, a movable side unit 84 and a base plate 83 are disposed on the shaping platform 5, and a first material layer 6 is formed on the base plate 83. When performing layered shaping using the first shaping region R, a base plate 33 is disposed on the shaping platform 5, and a first material layer 6 is formed on the base plate 33.

[0050] The recoating head drive mechanism 51 moves either the second shaping area recoating head 81 or the first shaping area recoating head 31. The recoating head drive mechanism 51, as described above... Figure 3 As shown, the device includes a motor 51g, a ball screw 51a, and a sliding member 51b. The motor 51g rotates the ball screw 51a. The sliding member 51b has a nut screwed onto the ball screw 51a. As described later, the second shaping area recoating head 81 and the first shaping area recoating head 31 share a movable body 32. The movable body 32 is fixed to the sliding member 51b. The second shaping area recoating head 81 or the first shaping area recoating head 31 is configured by mounting other components to the movable body 32. In other words, the second shaping area recoating head 81 and the first shaping area recoating head 31 can be interchanged by changing the components. When the sliding member 51b moves with the rotation of the ball screw 51a, the second shaping area recoating head 81 or the first shaping area recoating head 31 moves together with the sliding member 51b in the direction of arrow B. The ball screw 51a is rotatably supported and rotated by the motor 51g. The recoating head drive mechanism 51 is not limited to the structure comprising the motor 51g and the ball screw 51a. The recoating head drive mechanism 51 may be configured with any actuator, such as a linear motor.

[0051] like Figure 17 as well as Figure 18 As shown, the recoating head 31 for the first shaping area includes a material box 311, a movable body 32, a pair of scrapers 312, a sensor 313, a powder guide 314, and a material box support frame 315.

[0052] Material box 311 contains material powder M supplied from material supply unit 60. Sensor 313 detects the presence or absence of material powder M in material box 311.

[0053] The movable body 32 is the base that fixes and supports the material box 311 or material box 811. The movable body 21 is configured to reciprocate along the direction of arrow B on the base platform 4. The movable body 32 is moved by the recoating head drive mechanism 51, thereby moving the first shaping area recoating head 31 and the second shaping area recoating head 81 in the direction of arrow B. The movable body 32 is used jointly by the first shaping area recoating head 31 and the second shaping area recoating head 81. The movable body 32 has a generally cuboid shape that extends along a second horizontal direction orthogonal to the direction of arrow B, namely the direction of arrow C. The length of the long side of the movable body 32 is configured to be wider than the width of the base platform 4 in the direction of arrow C.

[0054] The guide members 321 are a pair of support platforms located at both ends of the movable body 32 in the direction of arrow C. The guide members 321 are respectively mounted on a pair of guide rails provided on the base platform 4. The first shaping area recoating head 31 and the second shaping area recoating head 81, which are moved by the recoating head drive mechanism 51, reciprocate along the guide rails on the base platform 4.

[0055] A pair of slots 322 are provided on the lower surface of the movable body 32. When the second shaping area is moved on the base platform 4 by the repainting head 81, the partition plates 821 move relative to each other inside the slots 322. In other words, the upper parts of the pair of partition plates 821 are respectively inserted into the pair of slots 322. The slots 322 extend from one end of the movable body 32 in the direction of arrow B to the other end, forming a straight line.

[0056] A pair of scrapers 312 are respectively provided on both sides of the movable body 32 in the direction of arrow B. The scraper 312 is a long strip-shaped member extending along the direction of arrow C. The scraper 312 flattens the material powder M discharged from the material discharge port 314a formed in the powder guide 314 to form a material layer 6. The length of the scraper 312 in the direction of arrow C is approximately the same as the width of the first shaping region R in the direction of arrow C.

[0057] A powder guiding section 314 is provided directly below the discharge opening of the material box 311. The powder guiding section 314 has a material discharge outlet 314a forming an opening. The powder guiding section 314 guides the flow of material powder M falling from the material box 311. Thus, the material powder M falls freely and is supplied to the first shaping area R.

[0058] The material box support frame 315 is a frame that fixes and supports the material box 311 to the movable body 32. The material box support frame 315 has a hollow, generally cuboid shape that extends in the direction of arrow C. The material box support frame 315 is installed on the upper part of the movable body 32 and houses the material box 311 inside.

[0059] The recoating head 31 of the first shaping area sprays material powder M stored in the material box 311 from the material discharge port 314a of the powder guide 314 while moving in the direction of arrow B over the first shaping area R. Furthermore, the recoating head 31 of the first shaping area smooths the material powder M sprayed onto the first shaping area R using a scraper 312, forming a material layer 6.

[0060] The scraper 312, material box 311, sensor 313, powder guide 314, and material box support frame 315 are detachably mounted on the movable body 32. When changing from the first shaping area recoating head 31 to the second shaping area recoating head 81, the scraper 312, material box 311, sensor 313, powder guide 314, and material box support frame 315 constituting the first shaping area recoating head 31 are removed from the movable body 32. Instead, the scraper 812, material box 811, sensor 813, and powder guide 814 constituting the second shaping area recoating head 81 are mounted on the movable body 32.

[0061] The shaping area restriction unit 8 is a device for manufacturing a three-dimensional object K within a second shaping area Rs. The shaping area restriction unit 8 is detachably installed within the chamber 1. The shaping area restriction unit 8 includes a repainting head 81 for the second shaping area, a non-movable side unit 82, and a movable side unit 84.

[0062] like Figure 3 As shown, the second shaping area recoating head 81 is disposed on the base platform 4 and is configured to reciprocate in the direction of arrow B via the recoating head drive mechanism 51. While moving within the chamber 1, the second shaping area recoating head 81 supplies material powder M to the second shaping area Rs and planarizes the material powder M to form a material layer 6. That is, the second shaping area recoating head 81 forms a material layer 6 on the second shaping area Rs. Figures 4 to 7 As shown, the second shaping area recoating head 81 includes a material box 811, a movable body 32, a sensor 813, a pair of scrapers 812, and a powder guide 814.

[0063] The material box 811 is a container that holds the material powder M inside. The material box 811 is supported on the movable body 32. The material box 811 has a shape that extends in the direction of arrow C, which is orthogonal to the direction of movement of the recoating head 81 for the second shaping area, i.e., the direction of arrow B. The volume of the material box 811 is designed to be as large as possible so that a three-dimensional object K can be created by inserting the material powder M only once. Specifically, the maximum length of the long side of the material box 811, i.e., in the direction of arrow C, is configured to be approximately the same as the width of the base platform 4 in the direction of arrow C. Moreover, the upper surface of the material box 811 is fixedly fixed in the upward direction from the upper surface of the movable body 32. The size of the material box 811 is determined by taking into account mechanical limitations such as the proper falling of the material powder M inside the material box 811, not obstructing the airflow of inactive gases, and not excessively loading the movement of the recoating head 81 for the second shaping area. The material box 811 has a material supply port 811a, a box outlet 811b, a first inclined surface 811c, a second inclined surface 811d, a third inclined surface 811e, and a fourth inclined surface 811f.

[0064] The material supply port 811a is an opening for feeding material powder M. The material supply port 811a is formed on the upper surface of the material box 811 and has a generally rectangular shape extending in the direction of arrow C. The length of the material supply port 811a in the direction of arrow C is configured to be the same as the width of the base platform 4 in the direction of arrow C. The box outlet 811b is a generally square-shaped opening for discharging material powder M from the material box 811. The box outlet 811b is formed on the lower surface of the material box 811 and extends in a direction substantially the same as the material discharge port 814a of the powder guide 814.

[0065] The first inclined surface 811c and the second inclined surface 811d are trapezoidal flat plates arranged along the direction of arrow C, sandwiching the box outlet 811b. The first inclined surface 811c and the second inclined surface 811d are inclined towards the box outlet 811b. The inclination angle of the first inclined surface 811c (the angle between the first inclined surface 811c and the horizontal plane) and the inclination angle of the second inclined surface 811d (the angle between the second inclined surface 811d and the horizontal plane) can be different from each other or the same. In practical application, the inclination angles of the first inclined surface 811c and the second inclined surface 811d are angles that allow the material powder M to slide off to a certain extent.

[0066] The third inclined surface 811e and the fourth inclined surface 811f are trapezoidal flat plates arranged along the direction of arrow B, sandwiching the box outlet 811b. The third inclined surface 811e and the fourth inclined surface 811f are inclined towards the box outlet 811b. The inclination angle of the third inclined surface 811e (i.e., the angle between the third inclined surface 811e and the horizontal plane) and the inclination angle of the fourth inclined surface 811f (i.e., the angle between the fourth inclined surface 811f and the horizontal plane) can be different or the same. In practical applications, the inclination angles of the third inclined surface 811e and the fourth inclined surface 811f are angles representing the degree to which the material powder M can slide off.

[0067] The first inclined surface 811c is adjacent to the third inclined surface 811e and the fourth inclined surface 811f, and the second inclined surface 811d is adjacent to the third inclined surface 811e and the fourth inclined surface 811f. Therefore, the lower part of the material box 811 has an inverted truncated cone shape. Because the lower part of the material box 811 is inverted truncated cone shape, the material powder M stored inside the material box 811 flows along the inclined surfaces 811c, 811d, 811e and 811f to the box outlet 811b. As a result, the amount of material powder M discharged from the box outlet 811b is stable, and the amount of material powder M discharged from the powder guide 814 is also stable.

[0068] A sensor 813 is fixed at the outlet 811b of the material box 811 to detect the presence or absence of material powder M inside the material box 811. When the sensor 813 determines that material powder M needs to be replenished to the material box 811, the recoating head 81 in the second forming area is temporarily stopped. The bottle containing material powder M can also be placed in a location that will not obstruct the stacking forming process within the chamber 1. In this way, the operator can replenish material powder M from the bottle to the material box 811 via the storage bin at the door. Thus, even when material powder M needs to be replenished, stacking forming can continue without opening the door during the stacking forming process.

[0069] A pair of scrapers 812 are respectively provided on both sides of the movable body 32 in the direction of arrow B. The scrapers 812 are positioned approximately at the center of the movable body 32 in the direction of arrow C. The scrapers 812 have a generally square shape extending along the direction of arrow C, and the length of the scrapers 812 is shorter than the length of the scraper 312. The scrapers 812 smooth the material powder M discharged from the material discharge port 814a formed in the powder guide 814 to form a material layer 6. The length of the long side of the scraper 812 in the direction of arrow C is approximately the same as the width of the second shaping region Rs in the direction of arrow C. When the scrapers 812 are installed on the movable body 32, the scrapers 812 are arranged inside the pair of partition plates 821 of the non-movable side unit 82.

[0070] A powder guide 814 is provided directly below the outlet 811b of the material box 811. The powder guide 814 guides the flow of material powder M falling from the outlet 811b of the material box 811. Thus, the material powder M is freely supplied to the second shaping region Rs. The powder guide 814 has a through-hole for the material powder M to fall through. The inlet of the through-hole is connected to the outlet 811b of the material box 811. The outlet of the through-hole is a material discharge outlet 814a. The material powder M contained in the material box 811 is discharged from the material discharge outlet 814a. The material discharge outlet 814a extends in the direction of arrow C, and its length in the direction of arrow C is approximately the same as the width of the second shaping region Rs in the direction of arrow C. When the powder guide 814 is mounted on the movable body 32, the material discharge outlet 814a of the powder guide 814 is positioned inside a pair of partition plates 821 of the non-movable side unit 82.

[0071] A pair of scrapers 812, a material box 811, a sensor 813, and a powder guide 814 are detachably mounted on the movable body 32.

[0072] To prevent the material powder M from clogging within the material box 811 and to facilitate its discharge, the recoating head 81 for the second shaping area can be vibrated. For example, by repeatedly switching the forward and reverse rotation of the motor 51g of the recoating head drive mechanism 51, the recoating head 81 for the second shaping area moves back and forth in the direction of arrow B. This causes the recoating head 81 for the second shaping area to vibrate. The component that applies vibration to the recoating head 81 for the second shaping area is not limited to the motor 51g. For example, an ultrasonic transducer can be provided on the outer side of the material box 811, and the vibration of the recoating head 81 for the second shaping area can be achieved by the ultrasonic transducer. The control of the vibrating component, such as the motor 51g or the ultrasonic transducer, is performed by a control device not shown. Furthermore, clogging of the material powder M can be prevented by optimizing the tilt angles of the inclined surfaces 811c, 811d, 811e, and 811f or the area of ​​the box outlet 811b. For example, by making the tilt angle of the first tilted surface 811c different from that of the second tilted surface 811d, or by making the tilt angle of the third tilted surface 811e different from that of the fourth tilted surface 811f, the shape of the inverted truncated cone can be made eccentric, making the material powder M less prone to clogging.

[0073] Figures 8 to 10 as well as Figure 13 The non-movable side unit 82 shown is a frame that is detachably mounted on the base platform 4. The non-movable side unit 82 is mounted on the base platform 4 inside the chamber 1 in such a way that it covers the first shaping area R other than the second shaping area Rs.

[0074] The non-movable side unit 82 includes a plate 822, a pair of partition plates 821, and a second anti-scattering frame 823. The outer edge 825 of the plate 822 has a generally square shape. A generally square opening 826 is formed at the center of the plate 822. The plate 822 is a plate that covers the first shaped region R outside the opening 826. The plate 822 with the opening 826 forms a second shaped region Rs that is smaller than the first shaped region R. A base plate 83 is disposed inside the opening 826, and a relatively small three-dimensional object K, such as a test piece, is manufactured within the opening 826. In other words, the area inside the opening 826 constitutes the second shaped region Rs.

[0075] The partition plate 821 is a pair of flat plates arranged in the direction of arrow B, clamping the opening 826. The partition plate 821 is erected on the upper surface of the flat plate 822. The partition plate 821 prevents the material powder M supplied from the material discharge port 814a of the recoating head 81 in the second shaping area from being dispersed outside the area clamped by the partition plate 821. The partition plate 821 extends from one end of the non-movable side unit 82 in the direction of arrow B to the other end, and is erected on the flat plate 822, protruding upwards. The position of the partition plate 821 in the direction of arrow C corresponds to the position of the slot 322 of the movable body 32. The height of the partition plate 821 is such that when the recoating head 81 in the second shaping area moves in the direction of arrow B, the upper surface of the partition plate 821 does not interfere with the size of the recoating head 81 in the second shaping area.

[0076] A second anti-scattering frame 823 is provided to cover the outer periphery of the opening 826. The second anti-scattering frame 823 is a hollow rectangular frame designed to cover the outer periphery of the opening 826. The second anti-scattering frame 823 protrudes downward and is vertically fixed to the plate 822. Here, the length of the outer edge of the second anti-scattering frame 823 in the direction of arrow C is defined as the width D1, and the length of the outer edge in the direction of arrow B is defined as the width W1.

[0077] Figures 11 to 13 The movable side unit 84 shown is detachably fixed to the shaping platform 5. The movable side unit 84 has a base 841 and a first anti-scattering frame 842.

[0078] A pedestal 841 is fixed to the shaping platform 5. The pedestal 841 includes a lower plate 841b with a square cross-section and an upper plate 841a with a square cross-section. The area of ​​the upper surface of the upper plate 841a is smaller than the area of ​​the upper surface of the lower plate 841b. The upper plate 841a is integrally fixed to the center of the upper surface of the lower plate 841b. A base plate 83 is directly fixed to the upper plate 841a. A first anti-scattering frame 842 is installed on the lower plate 841b. The lower plate 841b is fixed to the shaping platform 5.

[0079] The first anti-scattering frame 842 prevents the material powder M supplied to the second shaping area Rs from scattering onto the shaping platform 5. The first anti-scattering frame 842 is provided on the outer periphery of the base plate 83 and the upper plate 841a, and surrounds the side of the upper plate 841a. A gap W22 is formed between the first anti-scattering frame 842 and the side of the upper plate 841a. The first anti-scattering frame 842 is a hollow rectangular frame and is vertically disposed on the upper surface of the lower plate 841b. The first anti-scattering frame 842 protrudes upwards. Here, the length of the opening in the direction of arrow C of the first anti-scattering frame 842 is defined as the width D2, and the length of the opening in the direction of arrow B is defined as the width W21. The opening of the first anti-scattering frame 842 is larger than the outer edge of the second anti-scattering frame 823. That is, in comparing the size of the outer edge of the first anti-scattering frame 823 and the second anti-scattering frame 823, the relationship D2 > D1 and W21 > W1 holds true. The first anti-scattering frame 842 surrounds the second anti-scattering frame 823 at intervals.

[0080] The base plate 83 is used when manufacturing relatively small three-dimensional shapes K, such as test pieces. Material powder M is dispersed on the upper surface of the base plate 83 to form a first material layer 6. The base plate 83 has, for example, a square cross-section. The size of the upper surface of the base plate 83 and the size of the upper plate 841a of the pedestal 841 are smaller than the size of the opening of the second anti-scattering frame 823. In this way, when the shaping platform 5 moves in the vertical direction, the outer surfaces of the base plate 83 and the upper plate 841a are prevented from contacting the inner surfaces of the second anti-scattering frame 823.

[0081] The lower plate 841b of the movable side unit 84 is fixed to the shaping platform 5 by bolts or the like. The base plate 83 is fixed to the upper surface of the upper plate 841a of the movable side unit 84 by bolts or the like. When viewed from above, the base plate 83 is located inside the opening 826 of the non-movable side unit 82. Therefore, when the shaping platform 5 moves in the vertical direction, the base plate 83 causes the inner side of the opening 826, i.e., the second shaping area Rs, to move in the vertical direction. In this embodiment, the pedestal 841 and the base plate 83 have a plane that is approximately square, but are not limited to this.

[0082] As the shaping area limiting unit 8, multiple immobile side units 82 and multiple movable side units 84 can be prepared. That is, the immobile side units 82 and movable side units 84 of suitable specifications can be used to match the size of the three-dimensional object K to be stacked. Specifically, each immobile side unit 82 can also differ in the size of the opening 826 or the height of the second anti-scattering frame 823. Movable side units 84 suitable for each immobile side unit 82 are prepared. Specifically, each movable side unit 84 can also differ in the horizontal size of the base 841, the height of the base 841, the size of the opening of the first anti-scattering frame 842, or the height of the first anti-scattering frame 842. As the base plate 83, a base plate of suitable size can be selected to match the size of the three-dimensional object K to be stacked. The longitudinal and transverse dimensions of the base plate 83 must be smaller than the opening 826. The thickness of the base plate 83 can be freely selected, but it is preferred to be thin within the range of non-deformation. The thickness of the base plate 83 is, for example, about 18mm.

[0083] When using the shaping area restriction unit 8, the maximum height of the three-dimensional object K is determined by the heights of the first anti-scattering frame 842 and the second anti-scattering frame 823. That is, to prevent material powder M from scattering onto the shaping platform 5, it is preferable that, in the process of layering, the shaping platform 5 moves vertically within the area where the second anti-scattering frame 823 is inserted into the first anti-scattering frame 842. During the layering process, i.e., the repeated formation of material layers and the formation of cured layers, the second anti-scattering frame 823 remains inserted into the first anti-scattering frame 842. The movable range of the shaping platform 5 is approximately the same as the maximum height of the three-dimensional object K. Therefore, in the case of a three-dimensional object K with a large layering height, a first anti-scattering frame 842 and a second anti-scattering frame 823 with a large height are used.

[0084] When forming the first material layer 6, the upper surface of the base plate 83 must be higher than the upper surface of the flat plate 822. That is, the base plate 83 must be configured such that when the shaping platform 5 rises as high as possible without interference from components, the upper surface of the base plate 83 is higher than the upper surface of the flat plate 822. The pedestal 841 serves as a separator to raise the base plate 83. If sufficient height cannot be obtained using only the pedestal 841, a connecting member 85 as a separator can be provided between the movable side unit 84 and the base plate 83. By using the connecting member 85, the pedestal 841 can be shared even when using the relatively tall first anti-scattering frame 842 and the second anti-scattering frame 823. Figure 19 This indicates the state in which the base plate 83 is fixed to the pedestal 841 via the connecting member 85 using the first anti-scattering frame 842 and the second anti-scattering frame 823, which have a large height.

[0085] By changing the size of the non-movable side unit 82 and the movable side unit 84 in coordination with the size of the three-dimensional object K used for layering, the size of the second shaping area Rs and the maximum height of the three-dimensional object K can be changed.

[0086] Even without the pedestal 841, if the upper surface of the base plate 83 is higher than the upper surface of the flat plate 822, the pedestal 841 may not be required. In this case, the first anti-scattering frame 842 can be directly installed on the shaping platform 5. Moreover, even with the pedestal 841, the first anti-scattering frame 842 can be directly installed on the shaping platform 5.

[0087] Next, the method for installing the shaping area restriction unit 8 in chamber 1 and the method for manufacturing a three-dimensional object K using the shaping area restriction unit 8 will be described. The method for installing the shaping area restriction unit 8 will be illustrated by replacing the first shaping area recoating head 31 with the second shaping area recoating head 81. Furthermore, the order of the following processes can also be reversed.

[0088] First, install the base plate 83 and the movable side unit 84. Fix the base plate 83 to the movable side unit 84. (Example...) Figure 13 As shown, the movable side unit 84, on which the base plate 83 is installed, is fixed to the shaping platform 5.

[0089] Next, the recoating head 31 for the first shaping area is replaced with a recoating head 81 for a smaller area. Specifically, the scraper 312, sensor 313, material box 311, material box support frame 315, and powder guide 314 are removed from the movable body 32. Then, the scraper 812, powder guide 814, material box 811, and sensor 813 are installed on the movable body 32. Thus, the recoating head 81 for a smaller area is positioned on the base 4.

[0090] Next, a non-movable side unit 82 is placed on the base platform 4, covering the first shaping area R except for the second shaping area Rs. At this time, a base plate 83 is arranged in the opening 826 of the non-movable side unit 82.

[0091] Thus, the movable side unit 84 and the base plate 83 are installed, the recoating head 31 for the first shaping area is replaced with the recoating head 81 for the second shaping area, and the non-movable side unit 82 is placed on it. Thus, the shaping area restriction unit 8 is installed in the chamber 1.

[0092] like Figure 14As shown, the opening of the second anti-scattering frame 823 is larger than the outer edges of the base plate 83 and the upper plate 841a. Furthermore, the opening of the first anti-scattering frame 842 is larger than the outer edge of the second anti-scattering frame 823. Therefore, when the shaping platform 5 moves vertically, the outer surfaces of the base plate 83 and the upper plate 841a will not contact the inner surface of the second anti-scattering frame 823. Similarly, the outer surface of the second anti-scattering frame 823 will not contact the inner surface of the first anti-scattering frame 842.

[0093] As described above, after the shaping area restriction unit 8 is installed in the chamber 1, the shaping area restriction unit 8 is used to perform layered shaping. First, the operator puts the material powder M to be used into the material supply port 811a of the material box 811. Next, an inert gas is supplied into the chamber 1.

[0094] Here, the moving direction of the recoating head 81 for the second shaping area will be added. For the formation of the cured layer, it is sufficient if the recoating head 81 for the second shaping area clamps the second shaping area Rs and moves in only one direction. As in this embodiment, when the scrapers 812 are provided on both sides of the movable body 32, the moving direction can be different for each material layer 6 formed. For example, the moving direction of the recoating head 81 for the second shaping area can be set such that the moving direction of even-numbered layers is from left to right, and the moving direction of odd-numbered layers is from right to left.

[0095] On the other hand, the position of the recoating head 81 for the second shaping area can alter the airflow of inactive gases. For example, when the recoating head 81 for the second shaping area is located to the left of the second shaping area Rs, or to the right of the second shaping area Rs, the airflow of inactive gases may change, thus affecting the quality of the laminated shape. In particular, when using the shaping area restriction unit 8 for laminated shape to explore the use of new material powders, appropriate irradiation conditions are sometimes not yet known. In this case, sputtered material adhering to the cured layer is prone to form protrusions, and the scraper 812 may collide with these protrusions when forming the material layer 6. Therefore, when using material powder M for which appropriate irradiation conditions are not yet known, the stability of the laminated shape is important, and when forming a material layer 6, it is preferable to move the recoating head 81 for the second shaping area back and forth. In this way, the position of the recoating head 81 for the second shaping area becomes constant during the formation of the cured layer, thereby improving the stability of the laminated shape.

[0096] First, the first material layer 6 and the first cured layer are formed. The shaping platform 5 is positioned such that the distance between the lower end of the scraper 812 and the upper surface of the base plate 83 is equal to the amount of material layer 6. Here, the second shaping area is formed by reciprocating the recoating head 81. Figure 1 and Figure 2The diagram illustrates the reciprocating movement of the second shaping area recoating head 81 when its initial position is on the left. The second shaping area recoating head 81 moves from the left to the right of the second shaping area Rs, and then from the right to the left. Material powder M is dispersed from the material outlet 814a between a pair of separator plates 821, forming a first material layer 6 on the base plate 83. The irradiation device 13 irradiates a designated area of ​​the first material layer 6 with laser L to cure it, forming a first cured layer.

[0097] After the first cured layer is formed, the second material layer 6 and the second cured layer are formed. The shaping platform 5 lowers by one layer of material layer 6. The second shaping area is moved back and forth again by the recoating head 81. Material powder M is dispersed from the material outlet 814a between a pair of partition plates 821 to form the second material layer 6 on the first cured layer. The irradiation device 13 irradiates a designated area of ​​the second material layer 6 with laser L to cure it, forming the second cured layer.

[0098] Repeat the above process to form the third and subsequent cured layers. In this way, multiple cured layers are stacked to create a three-dimensional object K. Adjacent cured layers are firmly bonded to each other.

[0099] The movement range of the recoating head 81 for the second shaping area only needs to be set within the range where material layer 6 can be formed on the second shaping area Rs. A control device (not shown) controls the recoating head 81 for the second shaping area to move back and forth between a position further to the right of the opening 826 and a position further to the left of the opening 826. The movement range of the recoating head 81 for the second shaping area only needs to cover the second shaping area Rs, and therefore can be set to be narrower than the movement range of the recoating head 31 for the first shaping area. However, if the recoating head 81 for the second shaping area is too close to the second shaping area Rs during curing layer formation, it may be impossible to properly form an inactive gas flow directly above the second shaping area Rs. When the stability of the laminated shaping is important, the movement range should be set so that the position of the recoating head 81 for the second shaping area during curing layer formation is a position that is somewhat away from the second shaping area Rs. Furthermore, to prevent the material powder M from falling into the material recycling port 27b, it can be controlled so that the recoating head 81 in the second shaping area does not reach the material recycling port 27b located at the left and right ends of the base platform 4, or a cover can be installed to cover the material recycling port 27b.

[0100] like Figure 15As shown, during the manufacture of the three-dimensional object K, a portion of the material powder M supplied to the base plate 83 falls through the gap between the base plate 83 and the second anti-scattering frame 823 and accumulates inside the first anti-scattering frame 842. Furthermore, the material powder M pushed out by the repainting head 81 from the moved second shaping area accumulates between a pair of partition plates 821. The first anti-scattering frame 842 and the second anti-scattering frame 823 prevent the material powder M from scattering onto the shaping platform 5, which is further outward than the first anti-scattering frame 842. The partition plates 821 prevent the material powder M from scattering onto the flat plate 822, which is further outward than the partition plates 821. In particular, a groove 322 is provided on the lower surface of the movable body 32, through which the partition plates 821 are inserted, thereby further preventing the scattering of the material powder M.

[0101] The first anti-scattering frame 842 and the second anti-scattering frame 823 are not connected. Since the non-movable side unit 82 and the movable side unit 84 are independently provided, the shaping area restriction unit can be easily installed or removed. Using the shaping area restriction unit 8 of this embodiment, the areas where material powder M remains can be minimized. Therefore, the cleaning work required when using different material powders M after layering and shaping can be performed more easily. Specifically, only the interior of the first anti-scattering frame 842, the inner sides of the pair of partition plates 821, the upper surface of the base platform 4, and the second shaping area need to be cleaned with the recoating head 81. In particular, it can prevent the material powder M used from mixing into the material recovery unit 40 and the material supply unit 60. Therefore, the operation becomes simpler when using the material recovery unit 40 and the material supply unit 60 for layering and shaping.

[0102] The shaping region confinement unit 8 is suitable for use when stacking relatively small three-dimensional shapes K. The above description uses the shaping region confinement unit 8 to manufacture test pieces when exploring the use of new material powders, but the application of the shaping region confinement unit 8 is not limited to this. For example, the shaping region confinement unit 8 can also be appropriately used when preheating the material powder M to a high temperature for stacking. When using the shaping region confinement unit 8, the material powder M will not be dispersed on most of the shaping platform 5. Therefore, heat can be prevented from being transferred from the material powder M to the shaping platform 5 and its surrounding components.

Claims

1. A shaping region limiting unit, which is a shaping region limiting unit for a stacked shaping device, the stacked shaping device comprising: The base has an area capable of forming a three-dimensional object, namely the first shaping area; A shaping platform, located in the first shaping area, is configured to move vertically and is equipped with a base plate. The layered shaping device alternately and repeatedly forms a material layer containing material powder and a solidified layer. The shaping area limiting unit includes: The movable side unit is fixed to the shaping platform; The non-movable side unit is placed on the base platform, wherein, The movable side unit includes: The first anti-scattering frame is a hollow frame that protrudes upwards. The non-movable side unit includes: A flat plate, having an opening and placed on the base platform, covers the first shaped area in the portion outside the opening, forming a second shaped area smaller than the first shaped area; and The second anti-scattering frame is a hollow frame that protrudes downwards from the outer periphery of the opening. The first anti-scatter frame surrounds the second anti-scatter frame at intervals; and The second shaping area is formed using a recoating head, where the material layer is formed. The second shaping area uses a recoating head that includes: The movable body is configured to reciprocate along a first horizontal direction on the base platform; A material box is installed on the movable body to contain the material powder; The material discharge port discharges the material powder contained in the material box; and A scraper, mounted on the movable body, smooths the material powder discharged from the material outlet to form the material layer. The non-movable side unit further includes a pair of partition plates, which are vertically disposed on the upper surface of the flat plate and arranged along the first horizontal direction to clamp the opening. The material outlet and the scraper are disposed inside the pair of partition plates.

2. The shaping area limiting unit according to claim 1, wherein a pair of grooves are formed on the lower surface of the movable body. The upper portions of the pair of partition plates are respectively inserted into the pair of slots.

3. The shaping area limiting unit according to claim 1, wherein the length of the material box in the second horizontal direction orthogonal to the first horizontal direction is the same as the width of the base platform in the second horizontal direction.

4. The shaping area limiting unit according to claim 1, wherein the lower part of the material box has an inverted truncated cone shape.

5. The shaping area limiting unit according to claim 1, wherein the movable side unit further includes a pedestal. The platform has: Upper plate, for fixing the base plate; and The lower plate is fitted with the first anti-scattering frame and fixed to the shaping platform.

6. A layered shaping device, comprising the shaping region limiting unit as described in claim 1, wherein the layered shaping device comprises: A chamber that covers the first shaped area and the second shaped area; The base platform; The shaping platform; An irradiation device is used to irradiate the material powder with a laser or electron beam; and The shaping area restriction unit.

7. The layered shaping device according to claim 6, further comprising: The material recycling unit includes a sieve for removing impurities from the material powder discharged from the chamber, and a material conveying device for conveying the material powder.

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