Powder feeder and AM machine using powder feeder

Abstract

To provide a powder supply device.SOLUTION: According to one embodiment, a powder supply device is provided. The powder supply device has a container for holding powder, a supply passage for supplying powder to the container, and a valve structure for opening and closing the supply passage. The valve structure has a valve body that is movable between a first position that closes the supply passage and a second position that opens the supply passage, and a valve seat for the valve body to be seated. The valve body has a first seal part and a second seal part. The valve seat has a first seat part on which the first seal part is seated and a second seat part on which the second seal part is seated. The valve structure defines a sealed space when the first seal part is seated on the first seat part and the second seal part is seated on the second seat part, and has an exhaust passage for discharging gas from the sealed space and a pressure monitoring passage for monitoring pressure in the sealed space, .SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present application relates to a powder feeder and an AM machine using the powder feeder. [Background technology]

[0002] There are known technologies that directly model three-dimensional objects from three-dimensional data on a computer that represents the object. For example, the Additive Manufacturing (AM) method is known. One example is Direct Energy Deposition (DED), a deposition-based AM method. DED is a technology that models objects by locally supplying powdered metal material and melting and solidifying it together with the base material using an appropriate heat source.

[0003] When forming a three-dimensional object by DED, a DED nozzle is used to supply powder material to the printing position while a laser is irradiated to melt and solidify the powder material to form the object. Therefore, when forming a three-dimensional object by DED, it is necessary to continuously supply powder material to the DED nozzle. Generally, powder material is supplied to the DED nozzle by a powder supplying device, which supplies the powder material to the DED nozzle together with carrier gas. The powder supplying device holds the powder material and can supply the powder material to the destination, such as the DED nozzle, at a specified supply amount. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-219060 A Summary of the Invention [Problem to be solved by the invention]

[0005] When forming a large three-dimensional object by DED, the powder material held in advance in the powder supplying device may not be enough to complete the modeling, so it is necessary to replenish the powder supplying device with powder material during the modeling. Replenishing the powder supplying device with powder material is often done manually because it requires removing parts. Therefore, in order to replenish the powder supplying device with powder material, the modeling by DED is temporarily interrupted, which increases the time required for modeling. Therefore, it is desirable to be able to automatically supply the powder material to the powder supplying device rather than manually. In addition, by automatically supplying the powder material to the powder supplying device, the risk of humans inhaling the powder material can be reduced. Furthermore, when the powder supplying device supplies the powder material to a supply destination such as a DED nozzle together with a carrier gas, the container holding the powder material in the powder supplying device may be pressurized. Therefore, if the container holding the powder material is not properly sealed, the powder material may scatter from the container. Therefore, it is desirable to properly seal the container holding the powder material. One object of the present application is to provide a structure that can solve or alleviate at least a part of these problems. [Means for solving the problem]

[0006] According to one embodiment, there is provided a powder feeding apparatus comprising a container for holding powder, a feed passage for feeding powder to the container, and a valve structure for opening and closing the feed passage, the valve structure comprising a valve body movable between a first position that closes the feed passage and a second position that opens the feed passage, and a valve seat for the valve body to seat on, the valve body having a first seal portion and a second seal portion, the valve seat having a first seat portion against which the first seal portion seats and a second seat portion against which the second seal portion seats, the valve structure defining a space which is sealed when the first seal portion seats on the first seat portion and the second seal portion seats on the second seat portion. The valve structure has an exhaust passage for exhausting gas from the sealed space, and a pressure monitoring passage for monitoring the pressure in the sealed space. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 illustrates a schematic diagram of an AM apparatus for producing a structure, according to one embodiment. [Diagram 2] FIG. 2 illustrates a schematic cross-section of a DED nozzle, according to one embodiment. [Diagram 3] FIG. 1 illustrates a schematic diagram of a powder feeding device as a source of powder material according to one embodiment. [Figure 4] FIG. 13 is a cross-sectional view that illustrates a schematic configuration of a cover that is attached to the top end of the powder container, according to one embodiment. [Diagram 5] FIG. 5 is a bottom view of the cover shown in FIG. 4. [Figure 6] 5 is a diagram showing a state in which the supply passage of the cover shown in FIG. 4 is opened. FIG. [Figure 7] FIG. 13 is a cross-sectional view that illustrates a schematic configuration of a cover that is attached to the top end of the powder container, according to one embodiment. [Figure 8] FIG. 13 is a cross-sectional view that illustrates a schematic configuration of a cover that is attached to the top end of the powder container, according to one embodiment. [Figure 9] FIG. 13 is a cross-sectional view that illustrates a schematic structure near a supply passage of a powder container, according to one embodiment. [Figure 10] 1 is a flowchart illustrating a method for feeding powder material from a powder feeding apparatus according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the powder supplying device and the AM device using the powder supplying device according to the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same or similar elements are given the same or similar reference symbols, and in the description of each embodiment, duplicated descriptions of the same or similar elements may be omitted. In addition, the features shown in each embodiment can be applied to other embodiments as long as they are not mutually inconsistent.

[0009] FIG. 1 is a schematic diagram of an AM apparatus for manufacturing a molded object according to one embodiment. As shown in FIG. 1, the AM apparatus 100 includes a base plate 102. A molded object M is to be molded on the base plate 102. The base plate 102 may be a plate made of any material capable of supporting the molded object M. In one embodiment, the base plate 102 is disposed on an XY stage 104. The XY stage 104 is a stage 104 that is movable in two orthogonal directions (x direction and y direction) in a horizontal plane. The XY stage 104 may be connected to a lift mechanism that is movable in a height direction (z direction). In one embodiment, the XY stage 104 may not be provided.

[0010] 1, the AM apparatus 100 includes a DED head 200. The DED head 200 is connected to a laser source 202, a powder material source 300, and a gas source 206. The DED head 200 has a DED nozzle 250. The DED nozzle 250 is configured to eject the laser, powder material, and gas from the laser source 202, the powder material source 300, and the gas source 206.

[0011] The DED head 200 may be any type, and for example, a known DED head may be used. The DED head 200 is connected to a moving mechanism 220 and configured to be movable. The moving mechanism 220 may be any type, and for example, may be capable of moving the DED head 200 along a specific axis such as a rail, or may be configured as a robot capable of moving the DED head 200 to any position and orientation. In one embodiment, the moving mechanism 220 can be configured to move the DED head 200 along three orthogonal axes.

[0012] 1, the AM apparatus 100 according to one embodiment includes a controller 170. The controller 170 is configured to control the operation of various operating mechanisms of the AM apparatus 100, such as the above-mentioned DED head 200, various operating mechanisms 220, etc. The controller 170 can be comprised of a general computer or a special-purpose computer.

[0013] FIG. 2 is a schematic diagram showing a cross section of a DED nozzle 250 according to an embodiment. The DED nozzle 250 according to the illustrated embodiment is a DED nozzle body 259 having a generally truncated cone shape. The DED nozzle 250 according to the illustrated embodiment includes a first passage 252 through which a laser 251 passes in the center of the DED nozzle body 259. The laser that passes through the first passage 252 is emitted from a laser port 252a of the DED nozzle body 259. The DED nozzle body 259 also includes a second passage 254 outside the first passage 252 through which a powder material and a carrier gas for transporting the powder material pass. The powder material that passes through the second passage 254 is emitted from a powder port 254a. The DED nozzle body 259 also includes a third passage 256 outside the second passage 254 through which a shielding gas passes. The shielding gas that passes through the third passage 256 is emitted from a gas port 256a.

[0014] The second passage 254 is configured so that the powder material discharged from the DED nozzle 250 converges at a position substantially identical to the focal point 251a of the laser 251. In FIG. 2, the flow of the powder material and the carrier gas are indicated by dashed lines. The carrier gas can be an inert gas such as argon gas or nitrogen gas. It is more preferable to use argon gas, which is heavier than air, as the carrier gas. By using an inert gas as the carrier gas, the molten pool formed by melting the powder material can be covered with the inert gas to prevent oxidation. However, the flow of the carrier gas discharged from the powder port 254a may entrain the air outside. Therefore, the DED nozzle 250 shown in FIG. 2 can prevent the entrainment of the surrounding air by supplying the shield gas at a low speed from the third passage 256 arranged outside the second passage 254 from which the powder material and the carrier gas are discharged. By preventing the entrainment of the surrounding air (especially oxygen) by the carrier gas, it is possible to suppress the generation of a metal oxide film during molding, and also to form a molten pool with good wettability. In FIG. 2, the flow of shielding gas is indicated by arrows.

[0015] When performing modeling using the DED nozzle 250 as described above, it is necessary to supply powder material to the DED nozzle 250. As shown in Fig. 1, the DED nozzle 250 is connected to a powder material source 300. Fig. 3 is a schematic diagram showing a powder supplying apparatus 300 as the powder material source 300 according to one embodiment.

[0016] As shown in FIG. 3, the powder feeding apparatus 300 includes a powder container 302 for holding a powder material 301. A cover 350 is attached to the upper end of the powder container 302. The cover 350 may be removable from the powder container 302. When the cover 350 is removable from the powder container 302, the powder container 302 may be refilled with powder material by removing the cover 350. As described below, in one embodiment, the powder container 302 may be refilled with powder material while the cover 350 remains attached to the powder container 302. In one embodiment, an agitator 310 is disposed in the powder container 302 and configured to agitate the powder material in the powder container 302.

[0017] The bottom end of the powder container 302 is connected to a metering device 304. The metering device 304 is further connected to a gas source 306. The gas source 306 is a carrier gas, such as argon gas, for example. The gas can be supplied to the metering device 304. The gas source 306 may be the same as the gas source 206 shown in Figure 1. The powder material supplied from the powder container 302 to the metering device 304 is metered and delivered to the DED nozzle 250 along with the carrier gas.

[0018] FIG. 4 is a cross-sectional view showing the structure of a cover 350 attached to the upper end of the powder container 302 according to one embodiment. FIG. 5 is a bottom view of the cover 350 shown in FIG. 4. The cover 350 according to the illustrated embodiment is fixed to the upper end of the powder container 302 with bolts or the like (not shown). The cover 350 includes a cover body 352. In one embodiment, the powder container 302 is a generally cylindrical container, and the cover body 352 is generally disk-shaped. A supply port 354 is formed in the center of the cover body 352, and a supply passage 356 is defined so as to pass through the cover body 352 from the supply port 354.

[0019] In one embodiment, as shown in Fig. 4, cover 350 is provided with a valve structure 357 for opening and closing supply passage 356. Valve structure 357 includes a valve body 358. Valve body 358 is supported by pin 360 so as to be rotatable. A first O-ring 362 is attached to the lower surface of cover body 352. Also, a second O-ring 364 is attached to the outer side of first O-ring 362 on the lower surface of cover body 352. Note that valve 357 is omitted in Fig. 5.

[0020] The valve body 358 is configured to be rotatable about the pin 360 between a first position where the upper surface of the valve body 358 contacts the first O-ring 362 and the second O-ring 364, and a second position where the upper surface of the valve body 358 is separated from the first O-ring 362 and the second O-ring 364. When the valve body 358 is in the first position, the supply passage 356 is closed by the valve body 358. When the valve body 358 is in the second position, the supply passage 356 is open, and powder material can be filled into the powder container 302 through the supply port 354 and the supply passage 356. In the embodiment shown in FIG. 4, the first O-ring 362 and the second O-ring 364 form a valve seat on which the valve body 358 is seated. In the first position, the portion of the valve body 358 that contacts the first O-ring forms a first seal portion, and the portion that contacts the second O-ring 364 forms a second seal portion. 4, the first O-ring 362 and the second O-ring 364 are provided on the lower surface of the cover body 352, but in one embodiment, the first O-ring 362 and the second O-ring 364 may be provided on the upper surface of the valve body 358.

[0021] The powder supplying apparatus 300 in this embodiment can fill the powder container 302 with powder material from the supply port 354 and the supply passage 356 through the valve structure without removing the cover 350. For example, a tube 390 (see FIG. 6, etc.) for filling the powder material can be inserted into the supply port 354 and the supply passage 356 to replenish the powder container 302 with powder material. The tube 390 for filling the powder material can be automatically and / or remotely operated by a robot or the like to automatically and / or remotely supply the powder material to the powder supplying apparatus 300. In modeling using an AM device, from the viewpoint of safety, it is sometimes prohibited for humans to enter the modeling chamber during modeling. Therefore, if the powder supplying apparatus 300 can be replenished with powder material automatically instead of manually, it is possible to replenish the powder supplying apparatus 300 with powder material without interrupting modeling, which is efficient. In addition, according to the powder supplying apparatus 300 in this embodiment, it is possible to supply the powder material to the powder supplying apparatus 300 without human intervention, which is desirable from the viewpoint of safety.

[0022] In one embodiment, the valve structure 357 can include a resilient member 361 that biases the valve body 358 toward the first position. In one embodiment, the resilient member 361 can be a torsion spring, as shown in Figures 4 and 6. The torsion spring can be a spring that is biased against the pin 360. The elastic member 361 is wound around the supply passage 356. The valve body 358 is positioned at the first position for closing the supply passage 356 by the elastic member 361 unless a force for opening the supply passage 356 is applied. This prevents the valve body 358 from accidentally being opened and the powder material in the powder container 302 from being discharged through the supply passage 356. When filling the powder container 302 with the powder material, as shown in FIG. 6, a cylindrical tube 390 is inserted into the supply passage 356 from the supply port 354, the valve body 358 is moved to the second position to open the supply passage 356, and the powder material is supplied from the tube 390, thereby filling the powder container 302 with the powder material. When elastic member 361 is used, tube 390 can push down on valve body 358, thereby rotating valve body 358 from a first position to a second position, and when tube 390 is pulled out, elastic member 361 automatically returns valve body 358 to the first position, thereby closing supply passage 356. In such an embodiment, inserting tube 390 into supply passage 356 can automatically release valve 357, and removing tube 390 from supply passage 356 can automatically close valve 357.

[0023] As shown in FIG. 4, a ring-shaped groove 366 is formed between the first O-ring 362 and the second O-ring 364 in the cover body 352. As shown in FIG. 4, an exhaust passage 368 is formed in the ring-shaped groove 366, extending to the side surface of the cover body 352. The exhaust passage 368 is connected to a vacuum pump 372. A pressure monitoring passage 370 is further formed in the ring-shaped groove 366, extending to the opposite side surface of the cover body 352. The pressure monitoring passage 370 is connected to a pressure gauge 374. When the valve body 358 is disposed in the first position and the supply passage 356 is closed, the ring-shaped groove 366 is evacuated from the exhaust passage 368, and the pressure in the ring-shaped groove 366 is monitored from the pressure monitoring passage 370, so that a leak between the cover body 352 and the first O-ring 362 and the second O-ring 364 can be detected.

[0024] In the above embodiment, by monitoring the pressure in the ring-shaped groove 366 formed between the first O-ring 362 and the second O-ring 364, it is possible to monitor whether the supply passage 356 is reliably closed by the valve body 358. Only when the supply passage 356 is reliably closed by the valve body 358, is the supply of powder material from the powder supplying device 300 controlled to start, thereby preventing the powder material from scattering around.

[0025] FIG. 7 is a cross-sectional view showing the structure of a cover 350 attached to the upper end of the powder container 302 according to one embodiment. The cover 350 according to the embodiment shown in FIG. 7 can be the same as the cover 350 shown in FIG. 4 except for a valve structure 357 that opens and closes the supply passage 356. In the valve structure 357 according to the embodiment shown in FIG. 7, the valve body 358 is configured to be movable in the planar direction of the cover 350 and in a direction perpendicular to the planar direction. In the embodiment shown in FIG. 7, the valve body 358 is configured to be movable between a first position where the upper surface contacts the first O-ring 362 and the second O-ring 364, and a second position where the upper surface is separated from the first O-ring 362 and the second O-ring 364. When the valve body 358 is in the first position, the supply passage 356 is closed by the valve body 358. When the valve body 358 is in the second position, the supply passage 356 is open, and the powder container 302 can be filled with powder material through the supply port 354 and the supply passage 356. 7, the first O-ring 362 and the second O-ring 364 are also provided on the underside of the cover body 352, but in one embodiment, the first O-ring 362 and the second O-ring 364 may be provided on the upper surface of the valve body 358. The embodiment shown in FIG. 7 can also achieve the same effects as the embodiment described in FIG. 4-6.

[0026] FIG. 8 is a cross-sectional view showing the structure of a cover 350 attached to the upper end of the powder container 302 according to one embodiment. The cover 350 according to the embodiment shown in FIG. 8 has a similar structure to the cover 350 shown in FIG. 7, but the cover body 352 does not have the ring-shaped groove 366, the exhaust passage 368, and the pressure monitoring passage 370. In the embodiment shown in FIG. 8, a ring-shaped groove 394 is formed in the valve body 358 between a position (first seal portion) where the first O-ring 362 (first seat portion) contacts and a position (second seal portion) where the second O-ring 364 (second seat portion) contacts. As shown in FIG. 8, the ring-shaped groove 394 formed in the valve body 358 has an exhaust passage 396 formed therein, which extends to the side surface of the valve body 358. The exhaust passage 396 is connected to the vacuum pump 372. The ring-shaped groove 394 is further formed with a pressure monitoring passage 398 extending to the side surface of the valve body 358. The pressure monitoring passage 398 is connected to the pressure gauge 374. When the valve body 358 is placed in the first position and the supply passage 356 is closed, the ring-shaped groove 394 is evacuated from the exhaust passage 396, and the pressure in the ring-shaped groove 394 is monitored from the pressure monitoring passage 398, so that leakage between the valve body 358 and the first O-ring 362 and the second O-ring 364 can be detected. In the embodiment shown in FIG. 8, the first O-ring 362 and the second O-ring 364 are also provided on the lower surface of the cover body 352, but as one embodiment, the first O-ring 362 and the second O-ring 364 may be provided on the upper surface of the valve body 358. In the embodiment shown in FIG. 8, the same effects as those of the embodiment described in FIGS. 4-7 can be obtained.

[0027] FIG. 9 is a cross-sectional view that shows a schematic structure around the supply passage 356 of the powder container 302 according to one embodiment. In the embodiment shown in FIG. 9, the supply passage 356 of the powder container 302 is provided with a first valve 330 for opening and closing the first position and a second valve 332 for opening and closing the second position. In the embodiment shown in FIG. 9, an exhaust line 334 for evacuating is connected to the space between the first position and the second position of the supply passage 356. The exhaust line 334 is connected to a vacuum pump 372. In addition, a pressure monitoring line 336 for monitoring the pressure is further connected to the space between the first position and the second position of the supply passage 356. The pressure monitoring line 336 is connected to a pressure gauge 374. When the first valve 330 and the second valve 332 are closed, the space between the two valves is evacuated from the exhaust line 334, and the pressure is monitored from the pressure monitoring line 336, so that leakage from the first valve 330 and the second valve 332 can be monitored. The embodiment shown in FIG. 9 can also provide the same effects as the embodiment described with reference to FIGS.

[0028] 10 is a flow chart illustrating a method for feeding powder material from a powder feeding apparatus, according to one embodiment. In the embodiment shown in FIG. 10, the powder feeding apparatus may be any of the powder feeding apparatus 300 of the embodiments described above or any other powder feeding apparatus.

[0029] In a method for supplying a powder material according to an embodiment, first, a valve is opened to fill the powder material into the powder supplying device (S100). In the case of the powder supplying device 300 according to the embodiment shown in Figs. 4-6, the valve of the powder supplying device 300 can be opened by inserting the tube 390 from the supply port 354 into the supply passage 356 and rotating the valve body 358. It is preferable that the insertion of the tube 390 is performed automatically and / or remotely by a robot or the like. In the case of the powder supplying device 300 according to the embodiment shown in Figs. 7 and 8, the supply passage 356 can be opened by moving the valve body 358 downward and laterally. In the case of the powder supplying device 300 according to the embodiment shown in Fig. 9, the supply passage 356 can be opened by opening both the first valve 330 and the second valve 332. It is preferable that the valve is opened by electrical or electromagnetic action without manual intervention in the powder supplying device 300 shown in Figs. 7-9 as well.

[0030] After the valve is opened, the powder container 302 of the powder supplying device 300 is filled with powder material (S102). The powder material is filled, for example, by inserting a tube 390 and supplying the powder material into the powder container 302 through the inside of the tube 390. When filling the powder material into the powder container 302, it is desirable to prevent the powder from adhering to the seal portion on the upper surface of the valve body 358 or a seat portion such as an O-ring. Therefore, when supplying the powder material by inserting the tube 390, it is desirable to supply the powder material into the powder container 302 with the lower end of the tube 390 positioned below the valve body 358.

[0031] After the powder material is filled in the powder container 302, the valve of the powder feeding apparatus 300 is closed (S104). In the case of the embodiment shown in Figs. 4-6, in which the elastic member 361 is provided, when the tube 390 is withdrawn from the supply passage 356, the valve body 358 automatically closes the supply passage 356. In the case of the powder feeding apparatus 300 according to the embodiment shown in Figs. 7 and 8, after the tube 390 is withdrawn from the supply passage 356, the valve body 358 is moved to the first position to close the supply passage 356. In the case of the powder feeding apparatus 300 according to the embodiment shown in Fig. 9, the supply passage 356 can be closed by closing both the first valve 330 and the second valve 332.

[0032] After the valve of the powder supplying apparatus 300 is closed, it is confirmed whether the valve is closed (S106). In the powder supplying apparatus 300 according to the embodiment shown in Figs. 4-8, the ring-shaped grooves 366, 394 are evacuated via the exhaust passages 368, 396, and the pressure in the ring-shaped grooves 366, 394 is measured via the pressure monitoring passages 370, 398. If the pressure in the ring-shaped grooves 366, 394 is sufficiently low, it is determined that the sealing by the valve body 358 and the O-rings 362, 364 is properly performed. If the pressure in the ring-shaped grooves 366, 394 is higher than a predetermined value, it is determined that the sealing by the valve body 358 and the O-rings 362, 364 is not properly performed. If the sealing is not properly performed, maintenance such as cleaning the valve mechanism or replacing parts is required.

[0033] Once the valve closure is confirmed, the powder feeder 300 feeds the powder material to a desired location. For example, the powder feeder 300 can feed the powder material to the DED nozzle 250 of the AM apparatus 100.

[0034] According to the method of the above-described embodiment, it is confirmed that the valve is closed before supplying the powder material to the desired location, so that it is possible to prevent the powder material from leaking out of the supply passage 356, etc. during supply of the powder material.

[0035] At least the following technical ideas can be understood from the above-described embodiments. [Form 1] According to Form 1, there is provided a powder feeding apparatus comprising: a container for holding powder; a supply passage for supplying powder to the container; and a valve structure for opening and closing the supply passage, the valve structure having a valve body movable between a first position that closes the supply passage and a second position that opens the supply passage, and a valve seat on which the valve body is seated, the valve body having a first seal portion and a second seal portion, the valve seat having a first seat portion on which the first seal portion is seated and a second seat portion on which the second seal portion is seated, the valve structure defining a sealed space when the first seal portion is seated on the first seat portion and the second seal portion is seated on the second seat portion, and the valve structure having an exhaust passage for exhausting gas from the sealed space, and a pressure monitoring passage for monitoring a pressure in the sealed space.

[0036] [Mode 2] According to mode 2, in the powder supplying device according to mode 1, the supply passage is configured so that a tube for supplying powder to the container can be inserted therein.

[0037] [Mode 3] According to Mode 3, in the powder feeder according to Mode 1 or 2, the first seat portion comprises a first O-ring, and the second seat portion comprises a second O-ring.

[0038] [Mode 4] According to Mode 4, in the powder supplying device according to any one of Modes 1 to 3, the valve body is supported by a pin so as to be rotatable between a first position that closes the supply passage and a second position that opens the supply passage.

[0039] [Mode 5] According to Mode 5, in the powder feeder according to Mode 4, there is further provided an elastic member that biases the valve body towards the first position.

[0040] [Form 6] According to Form 6, there is provided a powder supplying device comprising a container for holding powder, a supply passage for supplying powder to the container, a first valve for opening and closing a first position of the supply passage, a second valve for opening and closing a second position of the supply passage, an exhaust passage for exhausting gas from a space between the first and second positions of the supply passage, and a pressure measurement passage for measuring pressure in the space between the first and second positions of the supply passage.

[0041] [Form 7] According to Form 7, there is provided a method for supplying a powder material from a powder supplying device, the powder supplying device having a container for holding powder, a supply passage for supplying powder to the container, and a valve for opening and closing the supply passage, the method comprising the steps of opening the valve, filling the container with powder material through the supply passage, closing the valve, checking whether the valve is closed, and supplying the powder material from the powder supplying device after it has been confirmed that the valve is closed.

[0042] [Form 8] According to Form 8, there is provided an AM apparatus for producing a molded object, the AM apparatus having a DED nozzle, the DED nozzle having a laser port for emitting laser light provided at a tip of the DED nozzle, and a laser passage communicating with the laser port and through which the laser light passes within the DED nozzle, a powder port for emitting powder material provided at the tip of the DED nozzle, and a powder passage communicating with the powder port and through which the powder material passes within the DED nozzle, and the AM apparatus has a powder supplying apparatus according to any one of Forms 1 to 6 for supplying powder material to the DED nozzle. [Explanation of symbols]

[0043] 100…AM device 300...Powder feeding device 301…Powder material 302…Powder container 304...Measuring device 306…Gas source 310...Stirring device 330…First valve 332…Second valve 334…Exhaust line 336…Pressure monitoring line 350…Cover 352…Cover body 354…Supply inlet 356…Supply passage 357…Valve mechanism 358…Valve body 360…pin 362…First O-ring 364…Second O-ring 366…Ring-shaped groove 368…Exhaust passage 370…Pressure monitoring passage 372…Vacuum pump 374…Pressure gauge 390…tube 394…Ring-shaped groove 396…Exhaust passage 398…Pressure monitoring passage

Claims

1. 1. A powder feeding apparatus, comprising: a container for holding the powder; a supply passage for supplying powder to the container; a valve structure for opening and closing the supply passage; the valve structure includes a valve body movable between a first position that closes the supply passage and a second position that opens the supply passage, and a valve seat on which the valve body is seated; The valve body has a first seal portion and a second seal portion, The valve seat has a first seat portion on which the first seal portion is seated and a second seat portion on which the second seal portion is seated, the valve structure defines a sealed space when the first seal portion seats on the first seat portion and the second seal portion seats on the second seat portion; The valve structure has an exhaust passage for discharging gas from the sealed space, and a pressure monitoring passage for monitoring the pressure in the sealed space. Powder feeding device.

2. 2. A powder feeding apparatus as claimed in claim 1, further comprising: The supply passage is configured to allow a tube for supplying powder to the container to be inserted therein. Powder feeding device.

3. 3. A powder feeding apparatus as claimed in claim 1 or 2, comprising: the first seat portion comprises a first O-ring and the second seat portion comprises a second O-ring.

4. 4. A powder feeding apparatus according to any one of claims 1 to 3, comprising: The valve body is supported by a pin so as to be rotatable between a first position at which the supply passage is closed and a second position at which the supply passage is opened. Powder feeding device.

5. 5. A powder feeding apparatus as claimed in claim 4, further comprising: a resilient member biasing the valve body toward the first position; Powder feeding device.

6. 1. A powder feeding apparatus, comprising: a container for holding the powder; a supply passage for supplying powder to the container; a first valve for opening and closing a first position of the supply passage; a second valve for opening and closing a second position of the supply passage; an exhaust passage for exhausting gas from a space between the first position and the second position of the supply passage; a pressure measurement passage for measuring a pressure in a space between the first position and the second position of the supply passage, Powder feeding device.

7. 1. A method for feeding a powder material from a powder feeding apparatus, comprising: The powder feeding apparatus comprises: a container for holding the powder; a supply passage for supplying powder to the container; a valve for opening and closing the supply passage; The method comprises: opening the valve; filling the container with powder material through the supply passage; closing the valve; determining whether the valve is closed; and after determining that the valve is closed, feeding powder material from the powder feeding apparatus with the valve closed. method.

8. An AM apparatus for manufacturing a shaped object, comprising: The DED nozzle includes: a laser port for emitting laser light provided at a tip of the DED nozzle, and a laser passage communicating with the laser port for passing the laser light through the DED nozzle; The DED nozzle has a powder port for ejecting a powder material provided at a tip thereof, and a powder passage communicating with the powder port for passing the powder material through the DED nozzle; The AM apparatus comprises a powder feeding device according to any one of claims 1 to 6 for feeding powder material to the DED nozzle. AM device.

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