Additive manufacturing powder supply module capable of transferring powder into containers under inert atmosphere

Abstract

The present invention relates to a module (2) for supplying additive manufacturing powder, comprising: a main hopper (29) for storing additive manufacturing powder, the main hopper (29) being adapted to be connected to a manufacturing module (4), the manufacturing module (4) being configured to use the powder contained in the main hopper (29) for additive manufacturing of an object, an inlet (211) of the supply module (2) being adapted to be connected to the manufacturing module (4) and for receiving the powder contained in the manufacturing module (4), a glove box (25) being adapted to accommodate a container (28), the glove box The box (25) is adapted to be tightly closed, a supply circuit configured to transfer powder contained in the glove box (25) to a main hopper (29), an extraction circuit, which is different from the supply circuit and is configured to transfer additive manufacturing powder from an inlet (211) of the supply module (2) to the container (28) when the container (28) is accommodated in the glove box (25), the glove box (25) comprising a glove (251), which, when the glove box (25) is closed, is used to close the container (28) once the container (28) is filled with powder.

Description

Technical Field

[0001] The present invention relates to the general field of additive manufacturing equipment, and more particularly to the field of a module for filling an additive manufacturing equipment with powder under a protective atmosphere. Background Art

[0002] Selective additive manufacturing builds three-dimensional objects by consolidating selected areas in successive layers of powdered material (metal powder, ceramic powder, etc.).

[0003] Typically, AM equipment is filled with AM powders under an inert and controlled atmosphere, especially in the case of reactive powders to protect the operator from possible inhalation or possible explosion.

[0004] To this end, additive manufacturing equipment typically includes a powder filling module with a glove box. A container or canister containing powder is placed into the enclosure, and once the atmosphere is established within the enclosure, an operator manually opens the container or canister.

[0005] Typically, an additive manufacturing system also includes a powder storage and supply module connected to a filling module. Powder is transferred from the filling module to the storage and supply module, where it is sieved and then placed in a buffer hopper to await use.

[0006] The additive manufacturing equipment also includes a manufacturing module connected to the storage and supply module. Powder is transferred from the buffer hopper to the manufacturing module, where it is spread into layers and then consolidated to produce a three-dimensional object.

[0007] After the object has been manufactured, the buffer hopper may contain a certain residual amount of unused powder.

[0008] If the next object to be manufactured needs to be produced from powder having a different composition or from powder having the same composition but from another powder manufacturing batch, the unused powder must be removed from the buffer hopper.

[0009] Currently, automated extraction units are used to remove unused powder from additive manufacturing equipment. These units are unable to repackage unused powder in small enough quantities into containers for easy transport. Specifically, it is impossible to refill easily transportable containers with unused powder under an inert atmosphere. Summary of the Invention

[0010] The object of the present invention is to provide an additive manufacturing device which can package a small portion of unused powder under a protective atmosphere.

[0011] In the case of the present invention, this object is achieved by a module for supplying powder for additive manufacturing, said module comprising

[0012] a main hopper for storing additive manufacturing powder, the main hopper being designed to be connected to a manufacturing module configured to additively manufacture an object from the powder located in the main hopper,

[0013] - an inlet of the supply module, the inlet being designed to be connected to the manufacturing module and to receive the powder located in the manufacturing module,

[0014] a glove box designed to accommodate the container, said glove box being closable in a leaktight manner,

[0015] - a supply line configured to transfer the powder located in the glove box to the main hopper,

[0016] an extraction line, which is distinct from the supply line and is configured to transfer additive manufacturing powder from an inlet of the supply module to the container when the container is housed in the glove box,

[0017] The glove box includes a glove that is used to close the container once it is filled with powder when the glove box is closed.

[0018] The presence of the return line and the housing makes it possible to move the powder to an empty container placed in the housing. In this way, unused powder can be refilled.

[0019] Advantageously, such a supply module is supplemented by the following various features or steps, considered alone or in combination:

[0020] The glove box includes a door located between the glove box and the main hopper, the door being movable between a first position in which a supply line between the glove box and the main hopper is open and a second position in which the supply line is closed and the glove box is sealed from the main hopper;

[0021] a reservoir connected to the main hopper, the reservoir being located below the main hopper and comprising an outlet designed to be connected to the manufacturing module via a manufacturing pipe,

[0022] a return line configured to redirect the additive manufacturing powder located in the reservoir to the inlet of the supply module,

[0023] a circulation-induction system designed to draw powder from the outlet of the reservoir to the inlet of the supply module;

[0024] The extraction circuit comprises a diverter, the supply module further comprising a bypass line connecting the diverter to the reservoir and designed to transfer powder directly from the diverter to the reservoir, the diverter being configurable as follows:

[0025] - extraction configuration, where additive powder from the supply module inlet is selectively redirected to the glove box,

[0026] - A loop-back configuration, in which additive powder from the supply module inlet is selectively redirected into a bypass line.

[0027] The present invention also relates to an additive manufacturing device comprising a module for supplying additive manufacturing powder as described above, and

[0028] A manufacturing module configured to additively manufacture an object from powder located in a main hopper, the main hopper being connected to the manufacturing module and the inlet of the supply module being connected to the manufacturing module.

[0029] Advantageously, but optionally, the device may be supplemented by a recycling system for recovering powder that has not consolidated during the additive manufacturing of the object and redirecting the recovered powder towards the inlet of the supply module.

[0030] The present invention also relates to a method for recharging additive manufacturing powder using a supply module as described above or using an additive manufacturing device as described above, comprising the following steps:

[0031] - Insert the empty container into the glove box and then close the glove box in a sealed manner,

[0032] - When the glove box is closed, once the container is filled with additive manufacturing powder transferred from the inlet of the supply module, the container is processed to close the container.

[0033] Advantageously, the method is supplemented by taking into account the following steps, either alone or in combination:

[0034] the step of conveying powder from the reservoir to the inlet of the supply module;

[0035] the step of conveying powder from the recovery system to an inlet of the supply module;

[0036] A preliminary step of sieving the powder. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other features and advantages of the present invention will become more apparent from the following description, which is intended to be illustrative and non-limiting only and should be read in conjunction with the accompanying drawings, in which:

[0038] Figure 1 Schematic diagram of an additive manufacturing apparatus according to one embodiment of the present invention.

[0039] Figure 2 Schematic diagram of a method for recharging additive manufacturing powder according to one embodiment of the present invention. DETAILED DESCRIPTION

[0040] Figure 1 An additive manufacturing apparatus 1 is shown comprising a powder supply module 2 and a manufacturing module 4 .

[0041] Supply Module

[0042] The supply module 2 includes a suction system 21 at the top, which is connected to a first gas exhaust line 23. The suction system 21 has an inlet 211 and an outlet 213 located at the bottom of the suction system 21. The suction system 21 is designed to generate a suction force at the inlet 211 that is directed into the interior of the suction system 21. The first gas exhaust line 23 may include a vacuum pump for generating the suction force. The suction system 21 is designed to receive additive manufacturing powder from the inlet 211 and store it. The stored powder is located at the bottom of the suction system 21 and can be extracted via the outlet 213. The suction system 21 may include a powder filter to prevent the powder from entering the first exhaust line 23. The suction system 21 includes a device capable of separating powder from the gas, such as a circulation filter 22. Other devices for separating powder from the gas exist, such as a filter chamber including a filter, a cyclone separator, or an exhaust box.

[0043] Supply module 2 includes a housing 25 positioned below suction system 21. Housing 25 includes walls defining a chamber. Housing 25 can be enclosed, such that the chamber is a three-dimensional structure hermetically sealed from the exterior of the device. The housing is designed to allow for the movement and processing of objects within the housing. In particular, the housing includes tools for moving and processing objects within the chamber when the chamber is enclosed.

[0044] Housing 25 can specifically be a glove box. In this case, the housing has two holes in which gloves 251 are placed to maintain the housing's tightness. Gloves 251 are used to move and handle objects within the chamber while it is sealed. By wearing gloves 251, an operator can handle objects within glove box 25 from outside the glove box. The glove box walls can be transparent to allow the operator to observe the objects being handled.

[0045] In particular, the object may be a container or canister 28 designed to contain additive manufacturing powder. The container and canister may be closed with a lid.

[0046] The housing's tooling is designed to move and seal the container or canister 28 within the chamber when the chamber is closed.

[0047] One of the walls of the housing 25 has a first door 253. The first door 253 is movable between an open position, in which a container can be moved from outside the device into the chamber or from the chamber to outside the device, and a closed position, in which the chamber is sealed from the outside of the device. The first door 253 can be closed to seal the housing from the outside. A lid can also be moved in and out to close the container or can.

[0048] The housing 25 may include a transfer area 255 within which one or more containers may be stored and stacked.

[0049] The housing 25 may include an oxygen sensor 257. The sensor 257 is designed to measure the oxygen content within the housing.

[0050] The housing 25 may comprise a supply line 259 for supplying air and a supply line 2511 for supplying an inert gas. The inert gas may in particular be nitrogen or argon.

[0051] The housing 25 may include a second gas exhaust line 2513 which may include a vacuum pump for generating suction.

[0052] The assembly of the supply line 259 for supplying air, the supply line 2511 for supplying an inert gas and the second gas exhaust line 2513 defines a gas flow control system which makes it possible to control the oxygen content and the inert gas content in the chamber.

[0053] The supply module 2 comprises a metering system 27 located below the suction system 21. The metering system 27 is connected to an outlet 213 of the suction system 21. Powder stored in the suction system 21 and located at the bottom of the suction system 21 can be extracted to the metering system 27 via the outlet 213.

[0054] The valve 24 is located between the suction system 21 and the metering system 27. In the open configuration, the valve 24 allows the passage of powder, while in the closed configuration, the valve 24 allows the suction system 21 to be sealed from the metering system 27. When the suction system 21 draws in powder, the valve 24 closes so that the suction occurs only at the inlet 211 and is directed to the interior of the suction system 21. Closing of the valve 24 can be automatically triggered by starting the suction of powder in the suction system 21.

[0055] The metering system 27 can isolate a precise amount of powder from the powder stored in the metering system. This precise amount can be delivered to an outlet 271 of the metering system 27. The outlet 271 is located within the housing 25 and has a valve 28. The valve 28 in an open configuration allows powder to pass from the metering system 27 to the interior of the housing 25, and the valve 28 in a closed configuration can isolate the metering system 27 from the interior of the housing 25 in a sealed manner.

[0056] The valve 28 is in particular closed when the first door 253 of the housing 25 is in the open position.

[0057] For example, the metering system can be a metering screw. The metering screw is incorporated into a barrel extending in a generally horizontal direction. As the screw moves and powder is poured from the suction system 21 into the metering system 27 through the open valve 24, the powder is transported by the screw along the direction of the barrel extension to the outlet 271.

[0058] The metering system can also be an airlock comprising two valves. The airlock has a predetermined volume and, when filled with powder via a first valve located on the side of the suction system 21, can isolate a precise volume of powder. This volume of powder can then be transferred to the housing 25 via a second valve located on the side of the housing 25.

[0059] The housing 25 may include a refill area designed to receive a powder container within the housing 25 below the outlet 271 of the metering system 27 .

[0060] The supply module 2 includes a main hopper 29 located below the housing 25. The main hopper 29 is a receptacle capable of storing additive manufacturing powder.

[0061] The main hopper 29 has a frustoconical volume and is designed to store a large amount of manufacturing powder. The main hopper 29 is oriented so that the axis of the frustoconical shape is vertical and the frustoconical volume has a smaller horizontal cross-section at the bottom of the hopper. The main hopper 29 has an outlet 293 located at the bottom of the main hopper.

[0062] The housing 25 comprises a second door 291 arranged between the chamber and the main hopper 29, said second door 291 being movable between an open position, in which the powder located in the chamber can be transferred to the main hopper 29, and a closed position, in which the chamber is separated from the main hopper 29 in a sealed manner.

[0063] The second door 291 or isolation door 291 is, for example, an isolation valve 291. The second door 291 defines a passage between the housing and the main hopper that can be opened or sealed in a controlled manner. The passage can be vertically oriented and wide enough to allow an operator to empty the contents of the powder canister from the housing 25 into the main hopper 29.

[0064] The supply module 2 comprises a flow splitter, which comprises an inlet and two outlets.

[0065] The inlet of the flow splitter is the inlet of the metering system 27 and is connected to the outlet 213 of the suction system 21. The first outlet of the flow splitter is the outlet 271 of the metering system 27.

[0066] The second outlet of the diverter passes through the metering system 27 in a vertical direction. The second outlet can be a continuation of the direction in which the powder poured from the suction system 21 reaches the metering system 27. The second outlet is connected to a bypass line 31. The bypass line 31 directly connects the second outlet of the diverter and the main hopper 29. The bypass channel 31 can be oriented vertically and pass through the glove box. The powder passing through the bypass line 31 does not reach any wall of the housing 25 and does not come into direct contact with the atmosphere of the housing 25. In particular, if the valve 28 is closed, the powder passing through the bypass line 31 does not come into contact with the atmosphere of the housing 25.

[0067] The second outlet is controlled by a valve 30. The valve 30 in an open configuration allows powder to pass from the metering system 27 to the bypass channel 31 and the valve 30 in a closed configuration prevents powder from passing from the metering system 27 to the bypass channel 31.

[0068] The flow diverter can be configured in an extraction configuration in which powder at the metering system outlet is selectively directed to the glove box 25. In this configuration, the valve 30 is in a closed configuration and the metering screw operates to deliver powder to the outlet 271 of the metering system.

[0069] The flow splitter can be configured as a loop-back configuration in which powder at the outlet of the metering system 21 is selectively directed to a second outlet of the flow splitter. In this configuration, the valve 30 is in an open configuration and the metering screw is at rest.

[0070] The flow divider can therefore be considered to be composed of the metering system 27 and the valve 30 .

[0071] The supply module 2 includes a metering device 33 located below the main hopper 29. The metering device 33 can adjust the flow rate of the powder delivered to the sieve 35 so as not to damage the mesh contained in the sieve 35. The metering device 33 is connected to the outlet 293 of the main hopper. The metering device 33 has an outlet 331 located at the bottom of the metering device 33.

[0072] The supply module 2 includes a sieve 35 located below the metering device 33. The sieve 35 is connected to the outlet 331 of the metering device 33. The sieve can filter agglomerated powder lumps and isolate them from the remaining powder in the receiver 351. The sieve includes a third discharge circuit 353, which can include a vacuum pump for generating suction.

[0073] Supply module 2 includes a reservoir 37 located below screen 35. Reservoir 37 can be a hopper having a frustoconical volume designed to store a large amount of manufacturing powder. The hopper can be oriented so that the axis of the frustoconical shape is vertical and the frustoconical volume has a smaller horizontal cross-section at the bottom of the hopper. Reservoir 37 has an outlet 371 located at the bottom of the reservoir.

[0074] When the second door 291 is in the open position, powder can be transferred from the glove box 25 to the reservoir 37. The powder can then pass from the glove box 25 to the main hopper 29, the metering device 33, the sieve 35, and finally to the reservoir 37 in sequence. In this way, a supply line configured to transfer powder located in the glove box 25 to the main hopper 29 or the further reservoir 37 can be defined. The second door 291, which defines a passage between the housing and the main hopper (which can be opened or sealed in a controlled manner), can open or close the supply line.

[0075] Supply module 2 includes a dry inert gas feed system 36. Feed system 36 can provide a flow of dry inert gas in a conduit 352 connected to sieve 35. The dry inert gas flow through conduit 352 is directed upward from the bottom so as to encounter the powder passing upward from the bottom of the sieve. The inert gas flow reaching sieve 35 via conduit 352 is also diffused into the upper portion of reservoir 37.

[0076] The pipe 352 and the third exhaust line 353 may be aligned in the same direction so that the inert gas flow may sequentially pass through the pipe 352 in the same direction, encounter the powder passing through the sieve, and finally pass through the third exhaust line 353 .

[0077] The feed system 36 may also provide a flow of dry inert gas in a conduit 372 connected to the bottom of the reservoir 37 , for example to the outlet 371 .

[0078] The outlet 371 of the reservoir is connected to a return line 391. The return line 391 connects the outlet 371 of the reservoir 37 and the inlet 211 of the suction system 21. The return line 391 connects the outlet 371 of the reservoir 37 and the housing 25. Powder can be transported from the reservoir 37 to the powder housing 25 via the suction system 21. The suction system 21 can draw powder from the reservoir 37 toward the suction system 21 via the return line 391.

[0079] The outlet 371 of the reservoir is also connected to a manufacturing conduit 392. The manufacturing conduit 392 connects the outlet 371 of the reservoir 37 and the manufacturing module 4 so that the powder contained in the reservoir 37 can be transferred to the manufacturing module 4.

[0080] The sieve 35 is located just above the reservoir 37 so that the powder contained in the reservoir 37 and transferred to the production module 4 is sieved as late as possible before being conveyed to the production module 4 .

[0081] The reservoir 37 may have a smaller volume than the main hopper 29. The purpose of the reservoir 37 is to store powder before it is conveyed to the manufacturing module 4 or the suction system 21. The reservoir 37 may be referred to as a buffer hopper.

[0082] Main hopper 29 is designed to contain the majority of the manufacturing powder required for additive manufacturing of one or more three-dimensional objects. The powder contained in main hopper 29 is intended to be transferred to manufacturing module 4. To this end, main hopper 29 is designed to be connected to manufacturing module 4, which is configured to additively manufacture objects from the powder contained in main hopper 29. Main hopper 29 is connected to the manufacturing module via a circulation of powder through metering device 33, sieve 35, reservoir or buffer hopper 37, and finally manufacturing conduit 392.

[0083] The supply module 2 comprises a controller 39 which allows the powder to be diverted from the outlet 371 to a return line 391 or a production pipe 392 .

[0084] The supply module 2 may comprise a humidity sensor 201 located on the first gas exhaust line 23. This humidity sensor 201 may know the humidity level of the gas exhausted by the suction system 21, ie the humidity level upstream of the inlet 211 of the suction system 21.

[0085] The supply module 2 may include a humidity sensor 202 located above the main hopper 29. The humidity sensor 202 may be aware of the humidity level in the main hopper 29 and directly provide information about the humidity level of the powder that may be present in the main hopper 29.

[0086] The supply module 2 may include a humidity sensor 203 connected to the dry inert gas feed system 36. The humidity sensor 203 may be aware of the humidity level of the dry inert gas delivered to the sieve 35 or the reservoir 37.

[0087] The supply module 2 comprises a circulation-inducing system including a suction system 21 .

[0088] The suction system 21 can draw powder from the reservoir 37 toward the suction system 21 via the return line 391 .

[0089] Manufacturing Module

[0090] The manufacturing module 4 includes a second suction system 41 at the top, connected to a fourth gas exhaust line 43. The second suction system 41 has an inlet 411 and an outlet 413 located at the bottom of the second suction system 41. The second suction system 41 is designed to generate suction at the inlet 411 that is directed into the interior of the second suction system 41. The inlet 411 of the second suction system 41 is connected to the manufacturing pipeline 392. The fourth gas exhaust line 43 may include a vacuum pump for generating suction. The suction system 41 may include a powder filter to prevent powder from entering the fourth gas exhaust line 43. The second suction system 41 includes a device capable of separating powder from the gas, such as a cyclone separator. Other devices for separating powder from the gas exist, such as a filter chamber including a filter, a circulation filter, or an exhaust tank. The second suction system 41 is designed to receive additive manufacturing powder from the inlet 411 and store it. The stored powder is located at the bottom of the second suction system 41 and can be extracted through the outlet 413.

[0091] The manufacturing module 4 comprises an airlock 45 located below the second suction system 41. The airlock 45 makes it possible to transfer powder without the printer chamber being in communication with the second suction system 41, thus avoiding damage to the printing housing in terms of inertness and pressure.

[0092] The manufacturing module 4 includes a diverging screw 47 and a converging screw 51, which are located on both sides of a housing 49 for manufacturing a three-dimensional object. The housing 49 is a printer chamber.

[0093] The manufacturing module 4 comprises a recovery system for recovering the scattered and unconsolidated powder at the end of the manufacturing process.

[0094] The recovery system may include a suction pipe 53 designed to draw in powder. The suction pipe 53 includes a suction nozzle 533 that forms the inlet of the suction pipe. The powder is drawn in at the suction nozzle and transferred to the other end of the pipe, which forms the outlet of the suction pipe 53. The manufacturing apparatus 1 may include a first recovery pipe 531 connecting the outlet of the suction pipe 53 and the inlet 211 of the suction system 21.

[0095] The recovery system may include a residual airlock 55 designed to recover powder from the converging screw 51 .

[0096] The manufacturing apparatus 1 may include a second recovery pipe 551 connecting the residual airlock 55 and the inlet 211 of the suction system 21 .

[0097] The residual airlock 55 makes it possible to transfer powder without the printer chamber being in communication with the second recovery duct 551 , thus avoiding damage to the printing housing in terms of inertness and pressure.

[0098] The manufacturing plant 1 may also comprise a second controller designed to circulate the powder from the recovery system to the suction system 21 in a controlled manner.

[0099] In this respect, the inlet 211 may be referred to as an inlet of the supply module 2 , which inlet is designed to be connected to the manufacturing module 4 and to receive the powder located in the manufacturing module 4 .

[0100] It should be noted that the manufacturing apparatus 1 includes sufficient valves at the intersections of the conduits 391 , 392 , 531 and 551 to allow the powder circulation mentioned in the description.

[0101] It should also be noted that powder can be transferred from the inlet 211 to the glove box 25. The powder passes sequentially through the suction system 21, the outlet 213 of the suction system 21, the metering system 27, the diverters 27 and 30 configured for its extraction, and finally the glove box 25. More specifically, the powder arriving in the glove box 25 can be poured into a container housed in the glove box 25. Therefore, there is an extraction line, separate from the supply line, configured to transfer the additive manufacturing powder from the inlet 211 of the supply module 2 to the container when the container is housed in the glove box 25, and the extraction line includes the diverters 27 and 30.

[0102] Filling method

[0103] Supply module 2 can be filled and sieved to produce powder according to the steps described below. Initially, housing 25 is sealed and does not include any containers; main hopper 29 and reservoir 37 are free of powder. The passage between the housing and main hopper, defined by second door 291, is initially sealed and closed.

[0104] During a first step S1, the oxygen content in the housing is adjusted to at least 18%. Oxygen sensor 257 measures the oxygen content in housing 25. Based on the measured value, air supply line 259 is activated to increase the oxygen content. Gas exhaust line 2513 is activated to maintain substantially atmospheric pressure in housing 25. Oxygen sensor 257 ensures that the oxygen content in the housing is at least 18%.

[0105] During a second step S2, the door 253 of the housing 25 is opened and a powder container or a plurality of powder containers are inserted into the housing 25. The container can be placed in a transport area 255 of the housing 25.

[0106] During a third step S3, the door 253 of the housing 25 is closed and the oxygen content in the housing is adjusted to no more than 2%. The inert gas supply line 2511 is activated to reduce the oxygen content. The gas exhaust line 2513 is activated to maintain substantially atmospheric pressure in the housing 25. Reducing the oxygen content to no more than 2% can be referred to as inerting. The oxygen sensor 257 ensures that the oxygen content in the housing is no more than 2%.

[0107] During the fourth step S4, main hopper 29 is filled. Isolation door 291 is activated to open the passage between the housing and the main hopper. An operator, using tool 251, handles a filled container in transfer area 255, opening the container and pouring its contents through the passage into main hopper 29. For example, the operator may don gloves from housing 25, pick up a filled container in transfer area 255, open it, and pour its contents through the passage into main hopper 29. The operator returns the empty container to transfer area 255 and continues in the same manner until all containers in the housing are empty.

[0108] During a fifth step S5 , the isolation door 291 is closed, thereby sealingly closing the passage between the housing and the main hopper.

[0109] During a sixth step S6, the oxygen content in the housing is adjusted to at least 18%. The air supply line 259 is activated to increase the oxygen content. The gas exhaust line 2513 is activated to substantially maintain atmospheric pressure in the housing 25. The oxygen sensor 257 ensures that the oxygen content in the housing is at least 18%.

[0110] During a seventh step S7 , the door 253 of the housing 25 is opened and the empty powder container is removed from the housing 25 .

[0111] During an eighth step S8 , the door 253 of the housing 25 is sealed closed.

[0112] During the ninth step S9, the powder is sieved and stored in a reservoir 37. The powder contained in the main hopper 29 is transferred to a sieve 35 via a metering device 33. The sieve 35 sieves the powder and extracts oversized powder lumps and powder aggregates. These powder lumps are transferred to a receiver 351 and stored there. The sieved powder passes through the sieve 35 and into a reservoir 37, where it is stored until use.

[0113] Reloading method

[0114] Supply module 2 allows for refilling of unused manufacturing powder. The process for refilling unused powder initially located in reservoir 37 is as follows, according to the following steps. Initially, housing 25 is hermetically sealed and contains no container; reservoir 37 contains unused powder. The passage between the housing and the main hopper, defined by isolation door 291, is initially hermetically sealed.

[0115] It should be noted that if unused powder is contained in the main hopper 29, it is transferred to the reservoir 37. This transfer can optionally be performed multiple times if the volume of the reservoir 37 is insufficient to accommodate all the unused powder.

[0116] During a first step E1, the oxygen content in the housing is adjusted to at least 18%. Oxygen sensor 257 measures the oxygen content in housing 25. Based on the measured value, air supply line 259 is activated to increase the oxygen content. Gas discharge line 2513 is activated to maintain substantially atmospheric pressure in housing 25. Oxygen sensor 257 ensures that the oxygen content in the housing is at least 18%.

[0117] During a second step E2 , the door 253 of the housing 25 is opened.

[0118] During a third step E3, an empty container or containers are inserted into housing 25. The container can be placed in transport area 255 of housing 25. The container's lid is also inserted. The container can be opened. The containers can be closed, particularly if they contain an inert atmosphere, i.e., a gas composition of no more than 2% oxygen and at least 98% inert gas.

[0119] During a fourth step E4 , the door 253 of the housing 25 is sealed closed.

[0120] During a fifth step E5, the oxygen content in the enclosure is regulated to be no greater than 2%. The inert gas supply line 2511 is activated to reduce the oxygen content. The gas exhaust line 2513 is activated to substantially maintain atmospheric pressure in the enclosure 25. The oxygen sensor 257 ensures that the oxygen content in the enclosure is no greater than 2%.

[0121] In a sixth step E6, unused powder is transferred from the reservoir 37 or the main hopper 29 to the suction system 21. The controller 39 is activated so that the outlet 371 of the reservoir is connected to the return line 391.

[0122] The inert gas supply line 372, connected to the top and bottom of the reservoir, is activated to drive unused powder into the return line 391. The suction system 21 is activated to generate a suction force at the inlet 211 directed into the interior of the suction system 21. This movement can be performed according to various possible conveying modes: dense phase mode, dilute phase mode, etc. For this purpose, the powder concentration and gas flow rate in the circulation pipe can be controlled.

[0123] During a seventh step E7 , a sequence of sub-steps is carried out.

[0124] This sequence is performed through a splitter that is configured in an extraction configuration.

[0125] During a first sub-step E71 , the empty containers are moved from the transfer area 255 to a refilling area below the metering system.

[0126] During a second sub-step E72, the metering system 27 is activated so as to isolate a quantity of powder from the powder stored in the suction system 21. This quantity is less than or equal to the maximum capacity of the container.

[0127] During a third sub-step E73, the metering system is activated to extract the powder. The container is then positioned so that the powder can enter it.

[0128] During a fourth sub-step E74, the container and its lid are processed using a tool 251 in order to close the container by means of the lid. The operator closes the container by means of the lid and places the filled container in a transition area.

[0129] If unused powder remains in the suction system and an empty container remains in the transition zone, the sequence of sub-steps is restarted. If both conditions are met, the sequence is restarted and sub-steps E71, E72, E73, and E74 are performed using a new empty container. Otherwise, the sequence is interrupted and the eighth step E8 is performed.

[0130] During an eighth step E8, the oxygen content in the housing is adjusted to at least 18%. The air supply line 259 is activated to increase the oxygen content. The gas discharge line 2513 is activated to substantially maintain atmospheric pressure in the housing 25. The oxygen sensor 257 ensures that the oxygen content in the housing is at least 18%.

[0131] During a ninth step E9 , the door 253 of the housing 25 is opened.

[0132] During a tenth step E10 , one or more filled and closed containers are removed from the housing 25 .

[0133] During an eleventh step E11 , the door of the housing is hermetically closed.

[0134] The supply module 2 comprises a housing 25 which makes it possible to fill the main hopper 29 with a powder container, and a suction system 21 , a metering system 27 , a main hopper, a powder metering device 33 , a powder sieve 35 and a reservoir 37 .

[0135] If powder is still stored in the reservoir 37 when the manufacturing process is completed, the unused powder can be transported to the suction system 21 via the return line 391 .

[0136] The presence of a housing downstream of the metering system then makes it possible to transfer the unused powder from the suction system 21 to an empty container placed in the housing. The unused powder can be refilled.

[0137] Unused powder can be repackaged in smaller parts than with the prior art. These parts, such as powder containers, are lightweight enough to be handled and moved by operators. This repackaging can be performed in a protective atmosphere within an enclosure.

[0138] It should be noted that metering system 27 and bypass conduit 31 allow powder to be circulated from the suction system to housing 25 or main hopper 29. In this way, unused powder from manufacturing module 4 can be re-screened before reuse without the need for refilling, as is the case with the prior art. This is because suction system 21 can draw in unused powder and then move it directly to main hopper 29 via bypass conduit 31. The unused powder can then be screened and stored in reservoir 37.

[0139] Method for recharging powder from a manufacturing module

[0140] In the refilling method just described, unused powder is initially located in the reservoir 37 or main hopper 29 .

[0141] Supply module 2 can also refill unused manufacturing powder originally located in manufacturing module 4. In this case, the manufacturing powder is transferred to manufacturing module 4 and then dispersed during the process of manufacturing the three-dimensional object. At the end of this process, a portion of the powder that has not consolidated and surrounds the manufactured object is recovered by the recovery system through suction pipe 53, while another portion of the unconsolidated powder (referred to as residual powder) is recovered by the converging screw and residual airlock.

[0142] During step P1 , unused powder is conveyed to the suction system 21 . The powder is sucked in by the suction system 21 and passes through the first recovery conduit 531 or the second recovery conduit 551 .

[0143] At the end of step P1 , the unused powder is contained in the suction system 21 .

[0144] If you want to discard the unused powder, continue with the refill method following steps E7 through E11 above.

[0145] If the unused powder is to be reused later, it is best to re-sieve the unused powder before refilling the unused powder. In this case, the refilling process includes the following steps.

[0146] During step P2, the unused powder is moved into the main hopper 29: the flow dividers (27, 30) are configured in a loop configuration so that the unused powder contained in the suction system 21 is conveyed to the bypass channel 31. The unused powder then flows from the outlet 213 of the suction system 21 through the bypass channel 31 to the main hopper 29.

[0147] During step P3, the sieve 35 sieves unused powder. The powder contained in the main hopper 29 is transferred to the sieve 35 via the metering device 33. The sieve 35 sieves the powder and extracts oversized powder lumps and powder aggregates. These powder lumps are transferred to the receiver 351 and stored therein.

[0148] At the end of step P3 , the sieved powder leaves the sieve 35 and enters the reservoir 37 .

[0149] The remainder of the refilling method follows steps E1 to E11 already explained above.

[0150] The presence of recovery channels 531 and 551 allows the recovery system to convey unconsolidated powder recovered in the manufacturing module 2 to the suction system 21. This powder can then be packaged in small enough quantities (for example in a powder container) to be moved by an operator.

[0151] The presence of a housing downstream of the metering system then allows unused powder to be poured from the suction system 21 into an empty container placed inside the housing. With the help of the housing 25 placed in this location, unused powder can be refilled under a protective atmosphere. This allows for repackaging under a protective atmosphere in quantities that can be delivered by the operator before disposal.

[0152] It should be noted that the powder can be re-screened before refilling. Using diverters 27 and 30, powder can be transferred from the suction system 21 through a bypass line 31 to the main hopper 29. This unused powder can then be re-screened through a sieve 35. The unused, re-screened powder is then returned to the suction system 21 via a return line 391. This time, the powder can be poured from the suction system 21 into the housing 25 for repackaging, with diverters 27 and 30 configured in an extraction configuration. Thus, the powder can be repacked in quantities that can be transferred by an operator under a protective atmosphere before being stored for subsequent reuse.

Claims

1. A supply module (2) for supplying additive manufacturing powder, comprising: a main hopper (29) for storing additive manufacturing powder, said main hopper (29) being designed to be connected to a manufacturing module (4) configured to additively manufacture an object from the powder located in the main hopper (29), an inlet (211) of the supply module (2), said inlet being designed to be connected to the manufacturing module (4) and to receive the powder located in the manufacturing module (4), a glove box (25) designed to accommodate the container (28), said glove box (25) being closable in a leaktight manner, - a supply line configured to transfer the powder located in the glove box (25) to the main hopper (29), Characterized in that the supply module (2) further comprises: an extraction line, distinct from the supply line, configured to transfer additive manufacturing powder from the inlet (211) of the supply module (2) to the container (28) when the container (28) is housed in the glove box (25), The glove box (25) comprises a glove (251) which, when the glove box (25) is closed, is used to close the container (28) once the container (28) is filled with powder, so that when the inlet (211) is connected to the manufacturing module (4), the powder not used after the additive manufacturing of the object is refilled in the container (28), The supply module includes: a reservoir (37) connected to the main hopper (29), said reservoir (37) being located below the main hopper (29), said reservoir (37) comprising an outlet (371) configured to be connected to a manufacturing conduit (392) connecting the outlet (371) of said reservoir with the manufacturing module (4), a return line (391) different from the manufacturing pipe (392), said return line (391) directly connecting the outlet (371) of the reservoir with the inlet (211) of the supply module (2), said return line (391) being configured to refill the container (28) with unused powder from the reservoir (37) when the container (28) is housed in the glove box (25), - a circulation-inducing system configured to suck the powder from the outlet ( 371 ) of the reservoir ( 37 ) to the inlet ( 211 ) of the supply module ( 2 ).

2. The supply module (2) according to claim 1, wherein The glove box (25) comprises a door (291) located between the glove box (25) and the main hopper (29), the door being movable between a first position in which a supply line between the glove box (25) and the main hopper (29) is open and a second position in which the supply line is closed and the glove box (25) is separated from the main hopper (29) in a sealed manner.

3. The supply module (2) according to claim 1, wherein The extraction circuit comprises a diverter (27, 30), the supply module (2) further comprising a bypass line (31), the bypass line (31) connecting the diverter (27, 30) to the reservoir (37) and designed to transfer powder directly from the diverter (27, 30) to the reservoir (37), the diverter (27, 30) being capable of being configured as follows: - an extraction configuration, wherein the additive powder coming from the inlet (211) of the supply module (2) is selectively redirected to the glove box (25), - a loop-back configuration, wherein additive powder coming from the inlet (211) of the supply module (2) is selectively redirected into the bypass line (31).

4. Additive manufacturing equipment (1), comprising: - a supply module (2) for supplying powder for additive manufacturing according to any one of claims 1 to 3, and A manufacturing module (4) configured to additively manufacture an object from powder located in a main hopper (29), said main hopper (29) being connected to the manufacturing module (4) and to which the inlet (211) of the supply module (2) is connected.

5. The additive manufacturing apparatus (1) according to claim 4, further comprising a recycling system (53, 55) for recycling powder that is not solidified during additive manufacturing of an object and redirecting the recycled powder to an inlet (211) of the supply module (2).

6. Method for recharging additive manufacturing powder using a supply module (2) according to any one of claims 1 to 3 or a device according to any one of claims 4 and 5, the method comprising the following steps: - inserting the empty container into the (E3) glove box (25) and then closing the (E4) glove box (25) in a sealed manner, - When the glove box (25) is closed, once the container is filled with additive manufacturing powder transferred from the inlet (211) of the supply module (2), processing (E74) the container to close the container.

7. A method for recharging additive manufacturing powder according to claim 6, using a supply module (2) according to any one of claims 1 and 3, comprising a step of conveying (E6) powder from a reservoir (37) to an inlet (211) of the supply module (2).

8. Method for recharging additive manufacturing powder according to claim 7, using the device according to claim 5, comprising the step of conveying (P1) powder from the recovery system (53, 55) to the inlet (211) of the supply module (2).

9. The method for recharging additive manufacturing powder according to any one of claims 6 to 8, comprising a step (P3) of preliminary sieving of the powder.

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