Layered object manufacturing apparatus

Abstract

This invention provides a stacking forming device configured to generate an airflow of inert gas flowing from front to back in at least the middle and lower layers of a chamber to prevent smoke retention and to minimize material leakage outside the device. The stacking forming device includes: a chamber containing a front panel; a door with an opening in the front panel; an irradiation device; a gas supply unit for supplying inert gas to the chamber; and a gas exhaust unit for discharging the inert gas from the chamber. The gas supply unit includes a middle nozzle and a lower nozzle. The middle nozzle is positioned to traverse the opening when the door is closed, and has one end supported by the front panel for swinging independently of the opening and closing of the door.

Description

Technical Field

[0001] This invention relates to a layered shaping device. Background Technology

[0002] There are various methods for lamination forming. For example, a lamination forming apparatus that performs powder bed fusion bonding forms a material layer in a forming region that is the area for forming the desired three-dimensional shape, and then irradiates the material layer with a laser or electron beam to form a cured layer. Then, the formation of material layers and cured layers is repeated alternately to form a three-dimensional shape as a lamination of multiple cured layers.

[0003] Typically, in lamination forming apparatuses, to prevent deterioration of the material layers and the cured layer, an inert gas is filled in the cavity covering the forming area during forming. When a laser or electron beam is used to irradiate and form the cured layer, smoke, known as fumes, is generated from the irradiation location. These fumes can attenuate the laser or electron beam or contaminate optical components, potentially affecting the quality of the three-dimensional object. Therefore, lamination forming apparatuses are configured to supply a predetermined concentration of inert gas into the cavity and exhaust the inert gas containing fumes from the cavity.

[0004] An opening for removing three-dimensional objects is formed in the chamber, and a door that can be opened and closed is provided on the opening. Hereinafter, in the chamber, the side with the opening, i.e., the side with the door, is designated as the front side, the direction facing the front side is designated as the back side, and the left and right directions from the front side to the back side are designated as the left and right sides, respectively. The space within the chamber is designated as upper, middle, and lower layers from a relatively high position.

[0005] Smoke is generated in the shaping area. Therefore, it is ideal to generate an airflow of inert gas directly above the shaping area, i.e., in the lower layer of the chamber, to remove the smoke.

[0006] The lamination forming apparatus disclosed in Japanese Patent 5982046B1 supplies inert gas primarily through a supply port located at the lower part of the left side panel of the chamber and a supply port located on the right side of the coating head that moves over the forming area. The lamination forming apparatus discharges inert gas primarily through an outlet located at the lower part of the right side panel of the chamber and an outlet located on the left side of the coating head. With this structure, an airflow of inert gas flowing from left to right can be formed over the forming area, and smoke is discharged outside the chamber with the airflow.

[0007] If the airflow is generated only directly above the shaping area, the smoke may sometimes remain trapped inside the chamber. U.S. Patent 10,987,867B2 discloses a layered shaping device that generates an airflow of inert gas in the upper, middle, and lower layers of a chamber. Summary of the Invention

[0008] [The problem the invention aims to solve]

[0009] Due to design constraints, it is sometimes difficult to generate airflow in the left-right direction. Alternatively, airflow in the front / back direction may be more suitable for removing smoke than airflow in the left-right direction. When generating airflow in the front / back direction, a gas supply unit with an inert gas supply port is considered to be installed directly on the door. However, the gas supply unit moves simultaneously with the opening and closing of the door, so there is a risk that the material accumulated on the gas supply unit may fall outside the device.

[0010] The present invention was made in view of this situation, and its object is to provide a stacked forming device configured to generate an airflow of inert gas flowing from the front to the back in at least the middle and lower layers of the chamber to prevent the retention of smoke and to prevent material leakage from the device.

[0011] [Technical means to solve the problem]

[0012] According to the present invention, a layered shaping device is provided, comprising: a chamber including a front panel with an opening, covering a shaping area as a region for forming a desired three-dimensional shape; a door disposed at the opening and configured to be openable and closable; an irradiation device disposed above the chamber for irradiating a material layer formed in the shaping area with a laser or electron beam to form a cured layer; a gas supply unit for supplying an inert gas to the chamber; and a gas discharge unit for discharging the inert gas from the chamber, the gas supply unit comprising: a middle nozzle disposed such that it traverses the opening when the door is closed, forming a middle outlet for blowing out the inert gas; and a lower nozzle disposed on the front panel side of the chamber, lower than the middle nozzle, forming a lower outlet for blowing out the inert gas, the middle nozzle having one end supported on the front panel and swinging independently of the opening and closing of the door.

[0013] [The effects of the invention]

[0014] The layered forming apparatus of the present invention includes at least a middle nozzle and a lower nozzle as a gas supply unit for supplying inert gas to a chamber. The middle nozzle is arranged such that it passes through an opening in the front panel when the door is closed. The lower nozzle is located on the front panel side of the chamber, positioned lower than the middle nozzle. This allows an airflow of inert gas flowing from front to back to be formed at least in the lower and middle layers of the chamber, preventing smoke retention and achieving more efficient smoke removal. Furthermore, one end of the middle nozzle is pivotally supported on the front panel, allowing it to pivot independently of the door. This ensures that the middle nozzle does not obstruct operations during preparation, maintenance within the chamber, or removal of three-dimensional objects. Additionally, if only the door is opened, the middle nozzle does not pivot, thus preventing material accumulated on the middle nozzle from falling out of the apparatus and leaking out. Attached Figure Description

[0015] Figure 1 This is an external view of the chamber and irradiation device.

[0016] Figure 2 It is a front sectional view of the layered shaping device.

[0017] Figure 3 It is a side sectional view of the layered shaping device.

[0018] Figure 4 This is a three-dimensional view of the gas exhaust section.

[0019] Figure 5 It is a 3D view of the coating head.

[0020] Figure 6 It is a 3D view of the coating head.

[0021] Figure 7 This is a schematic diagram of the irradiation device.

[0022] Figure 8 This is a schematic diagram of the pollution prevention device.

[0023] Figure 9 This is a cross-sectional view of the front side as seen from inside the cavity.

[0024] Figure 10 This is a 3D view of the lower nozzle.

[0025] Figure 11 This is a 3D view of the lower nozzle.

[0026] Figure 12 A chamber indicating that the door is open and the middle nozzle is closed.

[0027] Figure 13 The chamber indicating the open state of the door and the middle nozzle.

[0028] Figure 14 This is a 3D view of the middle layer nozzle.

[0029] Figure 15 This is a 3D view of the middle layer nozzle.

[0030] Figure 16 This is a top cross-sectional view of the middle layer nozzle.

[0031] Figure 17 This is an enlarged view of the middle bracket.

[0032] Figure 18 This is a 3D view of the upper nozzle.

[0033] Figure 19 This is a 3D view of the upper nozzle.

[0034] Figure 20 This is a side sectional view of the upper nozzle.

[0035] Figure 21 This is a 3D view of the side nozzle. Detailed Implementation

[0036] Hereinafter, embodiments of the present invention will be described using the accompanying drawings. In the drawings, fastening components such as pipes or hoses connecting the various parts, screws or bolts, and other constituent components not required in the description of the invention are sometimes appropriately omitted. The various modifications described below can be implemented in arbitrary combinations. As mentioned above, unless otherwise specified, the opening side of the chamber is defined as the front side.

[0037] like Figures 1 to 3 As shown, the lamination forming apparatus 1 of this embodiment includes: a chamber 10, a door 12, a material layer forming apparatus 3, an irradiation apparatus 4, a gas supply unit 2, a gas exhaust unit 13, an inert gas supply device 22, and a fume collector 23. The lamination forming apparatus 1 alternately repeats the formation of a material layer 92 by the material layer forming apparatus 3 and the formation of a curing layer 93 by the irradiation apparatus 4 to manufacture the desired three-dimensional shape.

[0038] The chamber 10 is substantially sealed and covers the shaping area R, which is the area for forming the desired three-dimensional shape. The chamber 10 is constructed by including a front panel 11 with an opening 111. The front panel 11 is constructed by including a frame 110. In this embodiment, the frame 110 is connected to an inert gas supply device 22 and a smoke collector 23 via piping, and inert gas flows inside the frame 110. Each part of the gas supply unit 2 is mounted on the frame 110, and an inert gas inlet is formed at the mounting position. The inert gas flowing inside the frame 110 is supplied to each part of the gas supply unit 2 through the inlet.

[0039] A door 12, configured to be openable and closable, is provided on the opening 111. In this embodiment, the door 12 has an observation window 121 at the top and a glove box 124 at the bottom. The observation window 121 is made of a transmissive material that attenuates scattered light from the laser L or electron beam and has a degree of transparency sufficient to allow visualization of the interior of the chamber 10. An operator can perform work inside the chamber 10 with the door 12 closed by using gloves in the glove box 124. A grip member 123 serves as a handle for opening and closing the door 12. A locking mechanism 125 locks and unlocks the door 12. In this embodiment, the door 12 is configured to be hinged to the front panel 11 at its left end and open and close by swinging, but other opening and closing mechanisms may also be used. For example, the door 12 may also be configured to slide up and down or left and right to open and close.

[0040] Inert gas supply device 22 supplies inert gas to gas supply unit 2 during the molding process, i.e., from the start of manufacturing the desired three-dimensional object to the completion of the manufacturing. Gas supply unit 2 supplies inert gas to chamber 10, which is filled with inert gas of a predetermined concentration. Inert gas supply device 22 is, for example, an inert gas generating device that generates inert gas from air or a gas storage bottle for storing inert gas. Inert gas containing fumes generated during the formation of curing layer 93 is discharged from chamber 10 via gas exhaust unit 13. Preferably, the inert gas discharged from chamber 10 via gas exhaust unit 13 is returned to chamber 10 via gas supply unit 2 after the fumes are removed by fume collector 23. Fume collector 23 is, for example, an electrostatic precipitator or a filter. Inert gas refers to a gas that does not substantially react with material layer 92 or curing layer 93, and an appropriate gas is selected from nitrogen, argon, helium, etc., depending on the type of material.

[0041] The gas exhaust section 13 discharges inert gas from the chamber 10. In this embodiment, the gas exhaust section 13 constitutes at least a portion of the back panel of the chamber 10. Figure 4 As shown, the gas discharge section 13 includes an exhaust duct 130 with an exhaust port 131 and a rectifier plate 132 disposed on the exhaust duct 130. In this embodiment, the two exhaust ports 131 are disposed in the middle of the chamber 10, that is, at approximately the same height as the opening 111. The inert gas containing smoke is rectified by the grid-shaped rectifier plate 132 disposed before the exhaust ports 131 and discharged outside the chamber 10 via the exhaust ports 131. As described above, the inert gas discharged from the exhaust ports 131 is conveyed to the smoke collector 23.

[0042] A material layer forming apparatus 3 is disposed within chamber 10 and forms a material layer 92 of a predetermined thickness. The material layer forming apparatus 3 includes a substrate stage 31 having a shaping region R, and a coating head 33 disposed on the substrate stage 31. The coating head 33 is configured to move horizontally via a coating head drive device (not shown) having any actuator. A shaping stage 35 is disposed in the shaping region R. The shaping stage 35 is configured to move vertically via a shaping stage drive device 37 having any actuator. During shaping, a substrate plate 91 may also be placed on the shaping stage 35, in which case the first layer of material layer 92 is formed on the substrate plate 91.

[0043] like Figure 5 and Figure 6 As shown, the coating head 33 has a material receiving section 331, a material supply port 332, and a material discharge port 333. The material receiving section 331 stores material, such as metal powder. The material supply port 332 is provided on the upper surface of the material receiving section 331 and serves as a receiving port for the material supplied to the material receiving section 331. When replenishing material to the coating head 33, material is supplied to the material supply port 332 via a guide device 16 provided in the chamber 10 from a material supply device (not shown). The material discharge port 333 is provided on the bottom surface of the material receiving section 331 and discharges the material inside the material receiving section 331. The material discharge port 333 has a slit shape extending in a horizontal direction orthogonal to the moving direction of the coating head 33. A blade 334 is provided on the side of the coating head 33 to uniformly form a material layer 92. While discharging the material contained in the material receiving section 331 from the material discharge port 333, the coating head 33 reciprocates horizontally in the shaping area R. At this point, the blade 334 flattens the discharged material to form a material layer 92.

[0044] An irradiation device 4 is disposed above the chamber 10, and irradiates the material layer 92 formed in the shaping region R with laser L, causing the material at the irradiated location to melt or sinter, thereby forming a solidified layer 93. In particular, the irradiation device 4 of this embodiment is configured to simultaneously irradiate multiple lasers L. Figure 7 As shown, the irradiation device 4 includes: a first irradiation device 41, a second irradiation device 42, a third irradiation device 43, and a fourth irradiation device 44. In this embodiment, the first irradiation device 41 and the second irradiation device 42, as well as the third irradiation device 43 and the fourth irradiation device 44, are respectively housed in the same frame.

[0045] The first illumination device 41 includes a light source 411, a focus control unit 412, an adjustment lens 413, and a scanning device 414. The light source 411 generates a laser L. The focus control unit 412 includes a focus control lens and a motor for moving the focus control lens back and forth, and adjusts the focus position of the laser L by moving the focus control lens back and forth along the optical axis. The adjustment lens 413 can be manually adjusted in position and can be fine-tuned for errors in the optical system that may occur during device assembly. The scanning device 414 is specifically a galvano scanner and includes an X-axis galvano mirror 414a for scanning the laser L along the X-axis; an X-axis actuator 414b for rotating the X-axis galvano mirror 414a; a Y-axis galvano mirror 414c for scanning the laser L along the Y-axis; and a Y-axis actuator 414d for rotating the Y-axis galvano mirror 414c.

[0046] The second irradiation device 42 includes a light source 421, a focusing control unit 422, an adjustment lens 423, and a scanning device 424. The light source 421 generates a laser L. The focusing control unit 422 includes a focus control lens and a motor that moves the focus control lens back and forth, adjusting the focal position of the laser L by moving the focus control lens back and forth along the optical axis. The adjustment lens 423 can be manually adjusted in position and fine-tuned for errors in the optical system that may occur during device assembly. The scanning device 424 is specifically a galvanometer scanner and includes: an X-axis galvanometer reflector 424a that scans the laser L along the X-axis; an X-axis actuator 424b that rotates the X-axis galvanometer reflector 424a; a Y-axis galvanometer reflector 424c that scans the laser L along the Y-axis; and a Y-axis actuator 424d that rotates the Y-axis galvanometer reflector 424c.

[0047] Preferably, the X-axis galvanometer reflector 414a and the Y-axis galvanometer reflector 414c are arranged symmetrically facing each other, and are configured as downstream galvanometer reflectors; that is, in this embodiment, the distance between the X-axis galvanometer reflector 414a and the X-axis galvanometer reflector 424a is close. This reduces the difference in the shape or energy density of the irradiated spot between the laser L scanned by the first irradiation device 41 and the laser L scanned by the second irradiation device 42. The lasers L scanned by the scanning device 414 of the first irradiation device 41 and the scanning device 424 of the second irradiation device 42 respectively irradiate the material layer 92 through the window 14 provided on the top plate of the chamber 10. In this embodiment, the first irradiation device 41 and the second irradiation device 42 are responsible for irradiating the left half of the shaping region R.

[0048] The third illumination device 43 includes: a light source 431, a focus control unit 432, an adjustment lens 433, and a scanning device 434. The light source 431 generates a laser L. The focus control unit 432 includes a focus control lens and a motor that moves the focus control lens back and forth, adjusting the focus position of the laser L by moving the focus control lens back and forth along the optical axis. The adjustment lens 433 can be manually adjusted in position and can be fine-tuned for errors in the optical system that may occur during device assembly. The scanning device 434 is specifically a galvanometer scanner and includes: an X-axis galvanometer reflector 434a that scans the laser L along the X-axis; an X-axis actuator 434b that rotates the X-axis galvanometer reflector 434a; a Y-axis galvanometer reflector 434c that scans the laser L along the Y-axis; and a Y-axis actuator 434d that rotates the Y-axis galvanometer reflector 434c.

[0049] The fourth illumination device 44 includes: a light source 441, a focus control unit 442, an adjustment lens 443, and a scanning device 444. The light source 441 generates a laser L. The focus control unit 442 includes a focus control lens and a motor that moves the focus control lens back and forth, adjusting the focus position of the laser L by moving the focus control lens back and forth along the optical axis. The adjustment lens 443 can be manually adjusted in position and fine-tuned for errors in the optical system that may occur during device assembly. Specifically, the scanning device 444 is a galvanometer scanner and includes: an X-axis galvanometer reflector 444a that scans the laser L along the X-axis; an X-axis actuator 444b that rotates the X-axis galvanometer reflector 444a; a Y-axis galvanometer reflector 444c that scans the laser L along the Y-axis; and a Y-axis actuator 444d that rotates the Y-axis galvanometer reflector 444c.

[0050] Preferably, the X-axis galvanometer reflector 434a and the Y-axis galvanometer reflector 434c are arranged symmetrically facing each other, and are configured as downstream galvanometer reflectors; that is, in this embodiment, the distance between the X-axis galvanometer reflector 434a and the X-axis galvanometer reflector 444a is close. This reduces the difference in the shape or energy density of the irradiated spot between the laser L scanned by the third irradiation device 43 and the laser L scanned by the fourth irradiation device 44. The lasers L scanned by the scanning devices 434 of the third irradiation device 43 and 444 of the fourth irradiation device 44 respectively irradiate the material layer 92 through the window 14 provided on the top plate of the chamber 10. In this embodiment, the third irradiation device 43 and the fourth irradiation device 44 are responsible for irradiating the right half of the shaping region R.

[0051] According to the irradiation device 4 described above, up to four lasers L can be irradiated simultaneously. In the stacked shaping device 1, which includes the irradiation device 4 configured to irradiate multiple lasers L or electron beams simultaneously, the amount of smoke generated per hour also increases, thus requiring more efficient smoke removal from the chamber 10.

[0052] The irradiation device 4 is not limited to the structure described above. In this embodiment, when irradiating multiple lasers L simultaneously, a light source 411, a light source 421, a light source 431, and a light source 441 are provided for each scanning device 414, scanning device 424, scanning device 434, and scanning device 444. However, a beam splitter or the like can be used to split the laser L generated by a single light source and deliver it to each scanning device 414, 424, 434, and 444. Alternatively, the irradiation device 4 can also be an electron beam irradiation device. For example, the irradiation device 4 includes: a cathode electrode that emits electrons, an anode electrode that collects and accelerates electrons, a solenoid that forms a magnetic field and focuses the direction of the electron beam in one direction, and a collector electrode that is electrically connected to the material layer 92, which is the irradiated object, and applies a voltage between the collector electrode and the cathode electrode. In this case, the cathode electrode and the anode electrode function as light sources that output the electron beam, and the solenoid functions as a scanning device that scans the electron beam. That is, the irradiation device 4 is configured to include at least one light source that generates a laser L or an electron beam and at least one scanning device that scans the laser L or the electron beam. Preferably, the irradiation device 4 includes at least one light source for generating a laser L or an electron beam and multiple scanning devices for scanning the laser L or electron beam, and is configured to simultaneously irradiate multiple laser L or electron beams.

[0053] A contamination prevention device 15 is provided on the top plate of chamber 10 to cover window 14. For example... Figure 8 As shown, the contamination prevention device 15 has a cylindrical frame 151 and a cylindrical diffusion member 152 disposed within the frame 151. An inert gas supply space 153 is provided between the frame 151 and the diffusion member 152. An opening 154 is provided on the bottom surface of the frame 151 inside the diffusion member 152. A plurality of fine holes 155 are provided on the diffusion member 152, and clean inert gas supplied to the inert gas supply space 153 passes through the fine holes 155 and fills the clean chamber 156. Then, the clean inert gas filling the clean chamber 156 is ejected through the opening 154 toward the lower part of the contamination prevention device 15. In this way, the area below the window 14 is filled with clean inert gas, and an airflow of inert gas from the window 14 toward the lower part is generated, thus preventing smoke from adhering to the window 14. Inert gas is supplied to the inert gas supply space 153 through a contamination prevention device supply port 21 provided on the top plate of the chamber 10. Since there is a possibility that there is a slight residual smoke in the gas returned from the smoke collector 23, the pollution prevention device supply port 21 is preferably connected only to the inert gas supply device 22.

[0054] Here, the implementation of the gas supply unit 2 is described in detail. The gas supply unit 2 supplies inert gas to the chamber 10. More specifically, the gas supply unit 2 supplies inert gas supplied from the inert gas supply device 22 and the smoke collector 23 to the chamber 10, thereby generating an airflow of inert gas flowing from the front to the back. Figure 9 The positional relationship of the various parts of the gas supply unit 2 is shown in a general way. The gas supply unit 2 of this embodiment includes a lower nozzle 5, a middle nozzle 6, an upper nozzle 7, and a plurality of side nozzles 8.

[0055] The lower nozzle 5, located in the lower layer within the chamber 10, generates an airflow of inert gas from the front to the back. This inert gas airflow in the lower layer directs the smoke generated in the shaping area R towards the back. The lower nozzle 5 is positioned on the front panel 11 side within the chamber 10, that is, on the front side of the chamber 10, closer to the front than the shaping area R, and is located lower than the middle nozzle 6. More specifically, in this embodiment, the lower nozzle 5 is mounted on the frame 110 of the front panel 11 at a position lower than the opening 111. Figure 10 and Figure 11 As shown, the lower nozzle 5 has a pair of lower conduits 51, a lower support member 52 for holding each lower conduit 51, and a lower bracket 53 disposed at the end of each lower conduit 51.

[0056] The lower conduit 51 is a tubular component that allows inert gas to flow through, and a lower outlet 511 for blowing out inert gas is formed on the back side, i.e. the shaping area R side. Inert gas supplied from the inert gas supply device 22 and the smoke collector 23 is transported to the lower conduit 51 through the inlet of the frame 110 and ejected from the lower outlet 511.

[0057] The lower support member 52 is, for example, a plate-like member, and holds the lower conduit 51 and fixes the lower conduit 51 to the frame 110.

[0058] The lower bracket 53 is, for example, an L-shaped metal plate, and is connected to the lower conduit 51 and the lower support member 52. That is, the lower bracket 53 has a first surface 531 for fixing the lower conduit 51 and a second surface 532 for fixing the lower support member 52.

[0059] Preferably, the blowing direction of the inert gas from the lower outlet 511 is adjustable. The lower nozzle 5 has multiple lower baffles 512 that are axially supported on the lower conduit 51 and can swing left and right. Multiple axial support holes 512a, which serve as through holes, are formed on the lower conduit 51, and the lower baffles 512 are fixed by bolts inserted into the axial support holes 512a. The left and right blowing direction is adjusted by fixing the lower baffles 512 after adjusting them to the desired angle. In addition, axial support holes 531a, which serve as through holes, and elongated holes 531b, which are arc-shaped elongated holes, are formed on the first surface 531 of the lower bracket 53, and the lower conduit 51 is fixed to the lower bracket 53 by bolts inserted into the axial support holes 531a and the elongated holes 531b, respectively. That is, the lower conduit 51 is supported so that it can swing up and down around the axial support hole 531a. The vertical blowing direction is adjusted by fixing the lower conduit 51 after adjusting it to the desired tilt. Furthermore, to avoid tangling material within the shaping area R, it is ideal that the inert gas from the lower outlet 511 is blown slightly upwards than the horizontal direction. For example, the blowing direction of the inert gas from the lower outlet 511 can be configured to be adjustable within a range of approximately 5° to approximately 25° when the horizontal direction is set to 0°.

[0060] In this embodiment, a pair of lower conduits 51 are provided, each capable of independent tilt adjustment. However, the lower conduits 51 can be integrally formed across the left and right sides, or multiple lower conduits 51 can be connected by connecting members. In this embodiment, the lower nozzle 5 is mounted on the frame 110, but it can be located at any position on the side of the front panel 11 within the chamber 10, lower than the middle nozzle 6. The component for adjusting the blowing direction of the lower outlet 511 is not limited to the structure described above. For example, the vertical blowing direction can be adjusted by a baffle that is axially supported on the lower conduit 51 and can swing up and down. A fan can also be provided in the lower nozzle 5 to improve the straightness of the inert gas ejected from the lower outlet 511.

[0061] The middle-layer nozzle 6 generates an inert gas flow from the front to the back within the middle layer of the chamber 10. This inert gas flow in the middle layer carries away any rising smoke that has not been removed by the lower-layer flow towards the back. Figure 12 and Figure 13 As shown, the intermediate nozzle 6 is disposed in the opening 111 of the front panel 11, configured such that one end is pivotally supported on the front panel 11, and pivots independently of the opening and closing of the door 12. When the door 12 is closed, the intermediate nozzle 6 is pressed against the front panel 11 and fixed in a predetermined position, passing through the opening 111 of the front panel 11. Hereinafter, the state in which the other end of the intermediate nozzle 6 is connected to the front panel 11 is referred to as the closed state of the intermediate nozzle 6, and the state in which the other end of the intermediate nozzle 6 is away from the front panel 11 is referred to as the open state of the intermediate nozzle 6. Figures 14 to 17As shown, the intermediate nozzle 6 has a pair of intermediate conduits 61, an intermediate support member 62 for holding each intermediate conduit 61, and an intermediate bracket 63 disposed at the end of each intermediate conduit 61.

[0062] The intermediate conduit 61 is a tubular component that allows inert gas to flow through it, and an intermediate outlet 611 for blowing out inert gas is formed on the back side, i.e. the shaping area R side. A pair of intermediate conduits 61 are connected to each other by a connecting member 613.

[0063] The intermediate support member 62 is, for example, a tubular member capable of supplying inert gas and pivotally holding the intermediate conduit 61. Specifically, the intermediate support member 62 has a flow section 623 and a fixing part 621 and a contact separation part 622 respectively provided at both ends of the flow section 623. The fixing part 621 is fixed to the frame 110 of the front panel 11. The fixing part 621 and the flow section 623 are connected via a hinge 624, and the flow section 623 and the contact separation part 622 pivot about the hinge 624. The contact separation part 622 pivots and contacts and separates from the frame 110 of the front panel 11. Furthermore, when the contact separation part 622 abuts against the frame 110, the contact separation part 622 is supported by a retaining plate 112 mounted on the frame 110. Inert gas is supplied to the flow section 623 via at least one of the fixing part 621 and the contact separation part 622. In this embodiment, inert gas is supplied to the flow section 623 from both the fixing part 621 and the contact separation part 622. Specifically, the fixing part 621 and the contact separation part 622 have inert gas inlets formed on the contact surfaces with the frame 110, and the inert gas inlets engage with the inert gas inlet formed on the frame 110. The inert gas supplied from the frame 110 via the fixing part 621 and the contact separation part 622 flows through the flow section 623, and the flow section 623 supplies inert gas to the middle layer duct 61. That is, the inert gas delivered from the inert gas supply device 22 and the smoke collector 23 is delivered to the middle layer duct 61 via the inlet of the frame 110 and the middle layer support member 62, and is ejected from the middle layer outlet 611.

[0064] The middle layer bracket 63 is, for example, an L-shaped metal plate, and is connected to the middle layer conduit 61 and the middle layer support member 62. That is, the middle layer bracket 63 has a first surface 631 for fixing the middle layer conduit 61 and a second surface 632 for fixing the middle layer support member 62.

[0065] Preferably, the blowing direction of the inert gas from the middle layer outlet 611 is adjustable. The middle layer nozzle 6 has multiple middle layer baffles 612 that are axially supported on the middle layer duct 61 and can swing left and right. Multiple axial support holes 612a, which serve as through holes, are formed on the middle layer duct 61, and the middle layer baffles 612 are fixed by bolts inserted into the axial support holes 612a. The left and right blowing direction is adjusted by fixing the middle layer baffles 612 after adjusting them to the desired angle. In addition, axial support holes 631a, which serve as through holes, and elongated holes 631b, which are arc-shaped elongated holes, are formed on the first surface 631 of the middle layer bracket 63, and the middle layer duct 61 is fixed to the middle layer bracket 63 by bolts inserted into the axial support holes 631a and elongated holes 631b, respectively. That is, the middle layer duct 61 is supported so that it can swing up and down around the axial support hole 631a. The vertical blowing direction is adjusted by fixing the middle layer conduit 61 after adjusting it to the desired tilt. For example, the blowing direction of the inert gas from the middle layer outlet 611 can be configured to be adjustable within a range of about -10° to about 10° when the horizontal direction is set to 0°.

[0066] In this embodiment, a pair of middle-layer conduits 61 are provided and connected to each other by connecting members 613. However, the middle-layer conduits 61 can be integrally formed throughout the left and right sides, or multiple middle-layer conduits 61 can be configured to independently adjust their tilt. In this embodiment, the middle-layer nozzle 6 is supported by the retaining plate 112 when the middle-layer nozzle 6 is closed, but other components can also be provided to directly or indirectly fix the middle-layer nozzle 6 to the front panel 11. In addition, the component for adjusting the blowing direction of the middle-layer outlet 611 is not limited to the above structure. For example, the vertical blowing direction can also be adjusted by a baffle that is axially supported on the middle-layer conduit 61 and can swing up and down. A fan can also be provided in the middle-layer nozzle 6 to improve the straightness of the inert gas ejected from the middle-layer outlet 611.

[0067] As explained above, the intermediate nozzle 6 can swing independently of the opening and closing of the door 12. When the door 12 is open, the intermediate nozzle 6 remains essentially closed, thus preventing material accumulated in the intermediate nozzle 6 from falling outside the device. Furthermore, by configuring the intermediate nozzle 6 to be able to open and close, it can be moved to a position that will not obstruct operations during preparation work such as mounting the base plate 91, maintenance such as cleaning or replacing parts in the chamber 10, and removal of manufactured three-dimensional objects. Additionally, the direction of inert gas flow can be adjusted with the door 12 open and the intermediate nozzle 6 closed, thus reducing the workload on the operator during adjustment.

[0068] Here, the method for adjusting the blowing direction is explained in detail. First, open the door 12 and the middle nozzle 6, and install an anemometer on the shaping area R, i.e., the shaping platform 35. The anemometer is configured to detect the airflow velocity at a measurement position in the lower layer of the chamber 10, for example, located approximately 50 mm from the upper surface of the material layer 92 used for shaping. Preferably, multiple measurement positions are arranged in a grid pattern when viewed from above the shaping area R, for example, the anemometer detects the airflow velocity at nine measurement positions. Then, inert gas is ejected from the lower nozzle 5. While confirming the airflow velocity, the installation angles of the lower baffle 512 and the lower duct 51 are adjusted to achieve the desired airflow, and then secured with bolts and nuts. Next, the detection height of the anemometer is changed. The anemometer is configured to detect the airflow velocity at a measurement position in the middle layer of the chamber 10, for example, located approximately 350 mm from the shaping surface. Similarly, the measurement positions are preferably arranged in a grid pattern when viewed from above in the shaped area R. Then, the middle layer nozzle 6 is closed, allowing inert gas to be ejected from the middle layer nozzle 6. While confirming the airflow velocity, the installation angles of the middle layer baffle 612 and the middle layer duct 61 are adjusted to achieve the desired airflow, and then secured with bolts and nuts.

[0069] The blowing direction of the inert gas from the lower blow-out port 511 and the middle blow-out port 611 is adjusted in this way. In the stacking forming device 1 of this embodiment, the middle nozzle 6 is not provided on the door 12 and can swing independently of the opening and closing of the door 12. Therefore, with the door 12 open, the airflow velocity of the middle layer and the blowing direction of the middle blow-out port 611 can be measured, resulting in good workability. The adjustment method described is just one example, and the specific sequence may be different. The blowing direction adjustment can be performed, for example, after the assembly of the device or after maintenance or modification where the airflow inside the chamber 10 changes. The blowing direction of the inert gas is affected by manufacturing or assembly errors of the parts involved in airflow generation or by the different specifications of each device. Therefore, even if each part is designed in advance to obtain the desired airflow, it is difficult to obtain the designed airflow. By providing blowing direction adjustment mechanisms on the lower nozzle 5 and the middle nozzle 6, the desired airflow can be easily obtained.

[0070] The upper nozzle 7, located in the upper layer of the chamber 10, generates an airflow of inert gas from the front to the back. This airflow of inert gas pushes the rising smoke downwards, and even so, moves the smoke rising near the window 14 towards the back. The upper nozzle 7 is positioned above the middle nozzle 6 on the front panel 11 side of the chamber 10, that is, on the front side of the chamber 10, beyond the shaped area R. More specifically, in this embodiment, the upper nozzle 7 is mounted on the frame 110 of the front panel 11 above the opening 111. Figures 18 to 20As shown, the upper nozzle 7 has: a first upper conduit 71, a second upper conduit 72, a third upper conduit 73, and an upper support member 74 for holding the first upper conduit 71, the second upper conduit 72, and the third upper conduit 73.

[0071] The first upper conduit 71, the second upper conduit 72, and the third upper conduit 73 are tubular components that allow inert gas to flow through, and upper outlets 711, 721, and 731 for blowing out inert gas are formed on the back side, i.e. the shaping area R side, respectively.

[0072] The first upper duct 71, which forms the upper outlet 711, is positioned closer to the window 14 than the second upper duct 72 and the third upper duct 73. The inert gas from the upper outlet 711 is directed towards the direct downward direction of the window 14 and is generally horizontal. However, since there is a possibility that nearby smoke may be drawn into the airflow of the inert gas from the upper outlet 711, it is ideal that the inert gas from the upper outlet 711 is directed slightly downward to prevent the inert gas from directly contacting the window 14. For example, when the horizontal direction is set to 0°, the inert gas from the upper outlet 711 is directed at approximately -5°.

[0073] The second upper conduit 72, with an upper outlet 721, and the third upper conduit 73, with an upper outlet 731, are positioned further forward than the first upper conduit 71. The blowing direction of the inert gas from the upper outlets 721 and 731 is set to a downward or oblique direction. For example, when the horizontal direction is set to 0°, the blowing direction of the inert gas from the upper outlets 721 and 731 is approximately -45°. That is, the upper outlets 721 of the second upper conduit 72 and 731 of the third upper conduit 73 are oriented further downward than the upper outlet 711 of the first upper conduit 71. The airflow of the inert gas from the upper outlets 721 and 731 suppresses the retention of smoke in the space above the middle nozzle 6.

[0074] The upper support member 74 is, for example, a tubular member capable of allowing inert gas to flow through, and holds the first upper conduit 71, the second upper conduit 72, and the third upper conduit 73. Inert gas supplied from the inert gas supply device 22 and the smoke collector 23 is conveyed through the inlet of the frame 110 and the upper support member 74 to the first upper conduit 71, the second upper conduit 72, and the third upper conduit 73, and is ejected from the upper outlet 711, the upper outlet 721, and the upper outlet 731. Furthermore, the flow velocity at the upper outlet 711 is ideally higher than the flow velocities at the upper outlets 721 and 731.

[0075] In this embodiment, the upper nozzle 7 has a first upper conduit 71, a second upper conduit 72, and a third upper conduit 73, but the number of upper conduits is not limited as long as an upper airflow can be generated. The blowing directions of the inert gas from the upper outlet 721 and the upper outlet 731 can be different, and the blowing direction can be directly downward, i.e., any angle including approximately -90°. In this embodiment, the upper nozzle 7 is mounted on the frame 110, but it can be located at any position above the middle nozzle 6 on the side of the front panel 11 within the chamber 10. In this embodiment, the blowing direction of the inert gas from the upper outlet 711, upper outlet 721, and upper outlet 731 is fixed, but it can also be configured to allow adjustment of the blowing direction.

[0076] Side nozzles 8 generate an inert gas flow from the front to the back on the left and right sides within the chamber 10. This inert gas flow on the left and right sides directs smoke that could be trapped in the left and right spaces within the chamber 10 towards the back, preventing backflow of the inert gas. The side nozzles 8 are respectively disposed on both sides of the front panel 11 within the chamber, separated by an opening 111. More specifically, in this embodiment, three side nozzles 8 are disposed further to the left of the opening 111, and three side nozzles 8 are disposed further to the right of the opening 111, with each side nozzle 8 mounted on the frame 110 of the front panel 11. Figure 21 As shown, each side nozzle 8 has a side conduit 81 and a side support member 82 for holding the side conduit 81.

[0077] The side duct 81 is a tubular member capable of supplying inert gas, and has a side outlet 811 formed on its rear side for blowing out inert gas. Inert gas supplied from the inert gas supply device 22 and the smoke collector 23 is delivered to the side duct 81 through the inlet of the frame 110 and ejected from the side outlet 811. The side support member 82 is, for example, a plate-like member, which holds the side duct 81 and fixes it to the frame 110.

[0078] In this embodiment, there are six side nozzles 8, three on each side, but the number of side nozzles 8 is not limited as long as airflow can be generated on the left and right sides. In this embodiment, the side nozzles 8 are mounted on the frame 110, but they can be positioned at any location on the front panel 11 side inside the chamber 10, separated by the opening 111. In this embodiment, the blowing direction of the inert gas from the side outlets 811 is fixed, but it can also be configured to allow adjustment of the blowing direction.

[0079] Based on the structure described above, an airflow of inert gas flowing in approximately one direction from the front to the back can be generated throughout the chamber 10, including the upper, middle, lower, and left and right sides. This prevents smoke from accumulating within the chamber 10 and allows for more efficient exhaust of smoke outside the chamber 10. Furthermore, it prevents the quality of the three-dimensional object from being degraded due to the smoke, and also suppresses the need to temporarily halt the shaping process to recover the smoke, thus shortening the shaping time. This invention is particularly effective when the amount of smoke generated per hour is high, for example, in a stacked shaping device configured to simultaneously irradiate multiple lasers L or electron beams.

[0080] Furthermore, since the material needs to be swept up and dispersed by the lower airflow, there is a speed limit to the lower airflow. For example, the average velocity of the airflow formed by the lower nozzle 5, measured at a position 50 mm above the shaping surface and viewed from above the shaping area R, also depends on the type of material; ideally, it is around 2 m / s. In this embodiment, by configuring the middle airflow to be faster than the lower airflow, smoke can be discharged more effectively while preventing material dispersion. That is, the average velocity of the inert gas airflow formed by the middle nozzle 6, viewed from above the shaping area R, is ideally configured to be faster than the average velocity of the inert gas airflow formed by the lower nozzle 5, viewed from above the shaping area R.

[0081] As several examples have been specifically shown, the present invention is not limited to the structure of the embodiments shown in the drawings, and various modifications or applications can be made without departing from the technical concept of the invention. For example, other inert gas supply ports or outlets may be provided on the chamber 10 or the components within the chamber 10, without obstructing the airflow generated by the gas supply unit 2. For example, inert gas supply ports and outlets may be provided on the side of the coating head 33. In addition, in this embodiment, two outlets 131 are formed in the exhaust duct 130, which serves as the back panel of the chamber 10, but the position and number of outlets 131 are not limited as long as airflow from the front to the back can be generated. For example, outlets 131 may also be formed on the top plate of the chamber 10 on the back side. However, in terms of efficiently discharging the airflow generated by the middle layer nozzle 6, it is ideal for outlets 131 to be provided at approximately the same height as the middle layer nozzle 6. In addition, to promote the discharge or circulation of inert gas, a fan may also be provided in the gas discharge unit 13 or the smoke collector 23, etc.

Claims

1. A layered shaping device, comprising: A chamber, comprising a front panel with an opening, covering a shaped area that forms the desired three-dimensional shape; A door is provided at the opening and configured to be openable and closable; An irradiation device is disposed above the chamber to irradiate the material layer formed in the shaping area with a laser or electron beam to form a solidified layer; The gas supply unit supplies inert gas to the chamber; and The gas discharge section discharges the inert gas from the chamber. The gas supply unit includes: A middle-layer nozzle, arranged to traverse the opening when the door is closed, forms a middle-layer outlet for blowing out the inert gas; and The lower nozzle, located below the middle nozzle on the front panel side within the chamber, forms a lower outlet for blowing out the inert gas. When the opening side is set as the front, the middle nozzle and the lower nozzle generate an airflow of the inert gas from the front to the back. The middle nozzle has one end that is oscillatingly supported on the front panel and oscillates independently of the opening and closing of the door.

2. The layered shaping device according to claim 1, wherein, The intermediate nozzle has: The middle layer conduit, having the middle layer blowout outlet; and The middle support member holds the middle conduit in place. It is configured to adjust the blowing direction of the inert gas from the middle layer outlet.

3. The layered shaping device according to claim 2, wherein, The front panel has a frame for the flow of the inert gas. The intermediate support member has: The fixing part is fixed to the frame; The contact separation portion is configured to be able to contact and separate from the frame; and The circulation section allows the inert gas supplied from the frame via at least one of the fixing section and the contact separation section to flow into the middle layer conduit.

4. The layered shaping device according to claim 2, wherein, The intermediate nozzle also has an intermediate baffle that is axially supported by the intermediate conduit and can swing left and right.

5. The layered shaping device according to claim 2, wherein, The intermediate nozzle has an intermediate bracket, which has a first surface for fixing the intermediate conduit and a second surface for fixing the intermediate support member. A shaft support hole and an elongated hole for bolt insertion are formed on the first surface of the middle bracket. The middle conduit is supported so that it can swing up and down around the axial support hole of the middle bracket.

6. The layered shaping device according to claim 1, wherein, The lower nozzle has: The lower conduit, having the lower blow-out port; and The lower support member holds the lower conduit. It is configured to adjust the blowing direction of the inert gas from the lower blow-out port.

7. The layered shaping device according to claim 6, wherein, The lower nozzle also has a lower baffle that is axially supported by the lower conduit and can swing left and right.

8. The layered shaping device according to claim 6, wherein, The lower nozzle has a lower bracket, which has a first surface for fixing the lower conduit and a second surface for fixing the lower support member. A shaft support hole and an elongated hole for bolt insertion are formed on the first surface of the lower bracket. The lower conduit is supported so that it can swing up and down around the shaft support hole of the lower bracket.

9. The layered shaping device according to claim 1, wherein, The gas supply unit further includes an upper nozzle, which is disposed on the front panel side of the chamber above the middle nozzle, forming an upper outlet for blowing out the inert gas.

10. The layered shaping device according to claim 9, wherein, The upper nozzle has: The first upper conduit has the upper blow-out port; The second upper conduit has the upper blow-out port; The third upper conduit, having the aforementioned upper blow-out port; and The upper support structure holds the first upper conduit, the second upper conduit, and the third upper conduit. The upper air outlet of the second upper conduit and the upper air outlet of the third upper conduit are oriented further downward than the upper air outlet of the first upper conduit.

11. The layered shaping device according to claim 1, wherein, The gas supply unit also includes a plurality of side nozzles, which are respectively disposed on both sides of the front panel side of the chamber through the opening, forming a side outlet for blowing out the inert gas.

12. The layered shaping device according to claim 1, wherein, The average velocity of the inert gas flow formed by the middle nozzle, viewed from above in the shaping area, is faster than the average velocity of the inert gas flow formed by the lower nozzle, viewed from above in the shaping area.

13. The layered shaping device according to claim 1, wherein, The irradiation device includes: At least one light source generates the laser or the electron beam; and Multiple scanning devices scan the laser or the electron beam. It is configured to simultaneously irradiate multiple lasers or electron beams.

14. The layered shaping device according to claim 1, wherein, The gas discharge section includes: An exhaust duct is formed with an outlet for discharging the inert gas; and A rectifier plate is disposed on the exhaust duct.

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