Additive manufacturing powder delivery module enabling transfer of powder to a container under inert atmosphere

Abstract

A provision module (2) for supplying additive manufacturing powder, a main hopper (29) for storing additive manufacturing powder, the 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) connected to the production module (4) and designed to receive the powder located in the production module (4); a glove box (25) designed to receive the container (28) and capable of being sealed and closed; a feed circuit configured to transfer the powder located within the glove box (25) to the main hopper (29); In a providing module (2), and an extraction circuit, distinct from the supply circuit, configured to transfer the additive manufacturing powder from the inlet (211) of the provision module (2) to the container (28) when the container (28) is received in the glove box (25); The glove box (25) includes a glove (251) that closes the container (28) when the container (28) is filled with powder while the glove box (25) is closed.

Description

[Technical field]

[0001] The present invention relates to the general field of additive manufacturing devices, and more particularly to the field of modules for loading powder into additive manufacturing devices under a protective atmosphere. [Background technology]

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

[0003] Traditionally, additive manufacturing machines are loaded with additive manufacturing powders under an inert and controlled atmosphere to protect the operator from possible inhalation or explosion, especially in the case of reactive powders.

[0004] For that purpose, additive manufacturing machines usually include a powder-filling module with a glove box: containers or pots with packaged powder are placed in the housing and manually opened by an operator after an atmosphere has been created in the housing.

[0005] Conventionally, additive manufacturing machines also include a powder storage and delivery module connected to the filling module, from which the powder is transferred to the storage and delivery module, where it is sieved and then deposited in a buffer hopper pending use.

[0006] The additive manufacturing apparatus also includes a fabrication module connected to the storage and delivery module, where the powder is transferred from the buffer hopper to the fabrication module, where it is dispersed in layers and then solidified to produce the three-dimensional object.

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

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

[0009] Currently, automated suction units are used to evacuate virgin powder from additive manufacturing equipment. These units do not allow the virgin powder to be repackaged in a container in quantities small enough to be easily transported, and in particular do not allow the virgin powder to be filled into a transportable container under an inert atmosphere. Summary of the Invention [Problem to be solved by the invention]

[0010] It is an object of the present invention to provide an additive manufacturing device capable of packaging virgin powder in small quantities under a protective atmosphere. [Means for solving the problem]

[0011] This object, in the context of the present invention, is to provide a method for additively manufacturing an object comprising: a main hopper for storing additively manufactured powder, the main hopper being designed to be connected to a manufacturing module configured to additively manufacture an object from said powder located in said main hopper; an inlet of the providing module connected to the manufacturing module and designed to receive the powder located in the manufacturing module; a glove box designed to receive the container and capable of being sealed and closed; a feed circuit configured to transfer the powder located within the glove box to the main hopper; A providing module comprising: an extraction circuit distinct from the supply circuit and configured to transfer the additive manufacturing powder from the inlet of the provision module to the container when the container is received within the glove box; the glove box includes a glove adapted to close the container when the container is filled with powder while the glove box is closed. This is achieved by a providing module for supplying additive manufacturing powder, characterized in that

[0012] The presence of the return circuit and the housing allows the powder to be transferred to an empty container placed in the housing. In this way, unused powder can be transferred. Such a provision module is advantageously complemented by the following various features or steps, considered alone or in combination: That is, the glove box includes a door between the glove box and the main hopper, the door being movable between a first position in which a feed circuit is open between the glove box and the main hopper and a second position in which the feed circuit is closed and the glove box is sealingly separated from the main hopper; a reservoir connected to the main hopper, the reservoir being located below the main hopper and including an outlet designed to be connected to a production module by a production duct; a return circuit configured to redirect the additive manufacturing powder located in the reservoir towards an inlet of the providing module; a circulation induction system designed to draw powder from an outlet of the reservoir to an inlet of the delivery module; Equipped with the extraction circuit includes a diverter; the delivery module further comprising a bypass circuit connecting the diverter to the reservoir and designed to transfer powder directly from the diverter to the reservoir; The bypass circuit is an extraction arrangement in which additive manufacturing powder coming from an inlet of the delivery module is selectively redirected towards the glove box; a loop-back configuration in which additive manufacturing powder coming from an inlet of the delivery module is selectively redirected to a bypass circuit; The diverter can be configured as follows.

[0013] The invention also relates to an additive manufacturing device comprising a module for providing an additive manufacturing powder as described above, a manufacturing module configured to additively manufacture an object from a powder located in the main hopper; Equipped with The main hopper is connected to the production module and the inlet of the delivery module is connected to the production module.

[0014] Advantageously, although optionally, the apparatus may be complemented by a recovery system for recovering powder that does not solidify as the object is being additively manufactured, and for redirecting the recovered powder towards the inlet of the delivery module.

[0015] The invention also relates to a method for transferring additively manufactured powder using a provision module or using an additive manufacturing apparatus as described above, comprising: inserting the empty container into the glove box and then sealingly closing the glove box; When the container is filled with additive manufacturing powder transferred from the inlet of the delivery module, handling the container to close the container while closing the glove box; Such a method advantageously comprises the following various steps, taken alone or in combination: That is, conveying powder from a reservoir to an inlet of a delivery module; conveying powder from a collection system to an inlet of a delivery module; A preliminary powder sieving step; is complemented by

[0016] Further characteristics and advantages of the invention will become more apparent from the following description, which is purely illustrative and non-limiting and which should be read in conjunction with the accompanying drawings, in which: [Brief description of the drawings]

[0017] [Figure 1]FIG. 1 is a schematic diagram of an additive manufacturing apparatus according to an embodiment of the present invention; [Diagram 2] FIG. 1 is a schematic diagram of a method for transferring additively manufactured powder according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] FIG. 1 shows an additive manufacturing apparatus 1 comprising a powder provision module 2 and a manufacturing module 4 .

[0019] (Provided module) The provision module 2 comprises at its top a suction system 21 connected to a first gas discharge circuit 23. The suction system 21 has an inlet 211 located at the bottom of the suction system 21 and an outlet 213. The suction system 21 is designed to generate a suction force towards the inside of the suction system 21 at the inlet 211. The first gas discharge circuit 23 can comprise 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 removed via the outlet 213. The suction system 21 can comprise a powder filter so that the powder does not enter the first discharge circuit 23. The suction system 21 comprises a device making it possible to separate the powder from the gas, for example a cyclofilter 22. Other devices for separating the powder from the gas are filter chambers, cyclones or discharge boxes with filters.

[0020] The delivery module 2 comprises a housing 25 located below the suction system 21. The housing 25 comprises various walls that define a chamber. The housing 25 is closable such that the chamber is a hermetically sealed volume to the exterior of the device. The housing is designed to allow objects placed inside the housing to be moved and handled. In particular, the housing comprises an implement for moving and handling objects within the chamber while the chamber is closed.

[0021] The housing 25 may in particular be a glove box. In this case, the housing has two orifices in which the glove box 251 is provided so that the airtightness of the housing is maintained. The glove 251 is an instrument for moving and handling objects in the chamber while the chamber is closed. By putting on the glove 251, an operator can handle objects located inside the glove box 25 from outside the glove box. The walls of the glove box may be transparent so that the operator can observe the objects being handled.

[0022] In particular, the object may be a container or pot 28 designed to contain additively manufactured powder. The containers and pots may be closed by a lid.

[0023] The housing fixture is designed to move and close a container or pot 28 within the chamber while the chamber is closed.

[0024] 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 the container can be moved from the outside of the device into the chamber or from the chamber to the outside of the device, and a closed position, in which the chamber is sealedly separated from the outside of the device. The first door 253 can be closed so that the housing is hermetically separated from the outside. It is also possible to move a lid in and out to close the container or pot.

[0025] The housing 25 may include a pass-through area 255 in which one or more containers may be stored and stacked.

[0026] The housing 25 can include an oxygen sensor 257. The sensor 257 is designed to measure the oxygen fraction within the housing.

[0027] The housing 25 may include a supply circuit 259 for supplying air and a supply circuit 2511 for supplying an inert gas. The inert gas may in particular be dinitrogen or argon.

[0028] The housing 25 may include a second gas exhaust circuit 2513, which may include a vacuum pump for generating a suction force.

[0029] The assembly of the supply circuit 259 for supplying air, the supply circuit 2511 for supplying an inert gas, and the second gas exhaust circuit 2513 defines a gas stream control system that makes it possible to control the oxygen fraction and the inert gas fraction in the chamber.

[0030] The delivery 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 via the outlet 213 towards the metering system 27.

[0031] A valve 24 is disposed between the suction system 21 and the metering system 27. In an open configuration, the valve 24 allows the passage of powder, and in a closed configuration, the valve 24 allows the suction system 21 to be sealedly isolated from the metering system 27. When the suction system 21 is suctioning powder, the valve 24 is closed, such that suction occurs only at the inlet 211 and is directed towards the interior of the suction system 21. The closure of the valve 24 can be automatically triggered by starting the suction of powder in the suction system 21.

[0032] The metering system 27 allows for a precise amount of powder to be separated from the powder stored within the metering system. This precise amount can be provided to an outlet 271 of the metering system 27. The outlet 271 is disposed within the housing 25 and has a valve 28. In an open configuration, the valve 28 allows for the passage of powder from the metering system 27 towards the interior of the housing 25, and in a closed configuration, the valve 28 allows for the sealing isolation of the metering system 27 from the interior of the housing 25.

[0033] The valve 28 is in particular closed when the first door 253 of the housing 25 is in the open position.

[0034] The metering system can be, for example, a metering screw, which is integrated into a barrel that extends in a direction that is conventionally horizontal. When the screw is operated, powder flows from the suction device 21 through the opening valve 24 into the metering device 27, and is conveyed by the screw in the direction of the barrel extension towards the outlet 271.

[0035] The metering system can also be an airlock that includes two valves. The airlock has a predetermined volume and allows for isolating a precise amount of powder as it is loaded through a first valve located on the side of the suction device 21. A volume of powder can then be transferred to the housing 25 through a second valve located on the side of the housing 25.

[0036] The housing 25 may include a transfer area designed to receive a container of powder inside the housing 25 below the outlet 271 of the metering system 27 .

[0037] The delivery module 2 comprises a main hopper 29 located below the housing 25. The main hopper 29 is a container making it possible to store additive manufacturing powder.

[0038] The main hopper 29 has a volume having a frusto-conical shape and is designed to store a large amount of production powder. The main hopper 29 is oriented so that the axis of the frusto-conical shape is vertical and the frusto-conical 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.

[0039] The housing 25 is disposed between the chamber and the main hopper 29 and includes a second door 291 movable between an open position that allows powder located in the chamber to be transferred to the main hopper 29 and a closed position that sealably separates the chamber from the main hopper 29.

[0040] The second door 291 or isolation door 291 is, for example, an isolation valve 291. The second door 291 defines a passageway between the housing and the main hopper that can be hermetically opened and closed in a controlled manner. The passageway can be vertically oriented and wide enough to allow an operator to empty the contents of a pot of powder from the housing 25 into the main hopper 29.

[0041] The supply module 2 comprises a diverter, which comprises one inlet and two outlets.

[0042] The inlet of the diverter 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 diverter is the outlet 271 of the metering system 27.

[0043] The second outlet of the diverter passes vertically through the metering system 27. 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 circuit 31. The bypass circuit 31 directly connects the second outlet of the diverter with the main hopper 29. The bypass channel 31 is oriented vertically and can pass through the glove box. The powder that passes through the bypass circuit 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, when the valve 28 is closed, the powder that passes through the bypass circuit 31 does not come into contact with the atmosphere of the housing 25.

[0044] The second outlet is controlled by a valve 30. In an open configuration, the valve 30 allows the passage of powder from the metering system 27 towards the bypass channel 31, and in a closed configuration, the valve 30 prevents the passage of powder from the metering system 27 towards the bypass channel 31.

[0045] The diverter can also be configured in an extraction configuration, where powder at the outlet of the metering system is selectively directed towards the glove box 25. In this configuration, the valve 30 is in a closed configuration and the metering screw is operatively set to convey powder towards the outlet 271 of the metering system.

[0046] It is also possible to configure the diverter in a loop-back configuration, where powder at the outlet of the metering system 21 is selectively directed towards a second outlet of the diverter. In this configuration, the valve 30 is in an open configuration and the metering screw is stationary.

[0047] A diverter can therefore be considered to be formed by the metering system 27 and the valve 30 .

[0048] The supply module 2 comprises a metering device 33 arranged below the main hopper 29. The metering device 33 makes it possible to regulate the flow rate of powder fed to the sieve 35 so as not to damage the screens contained inside 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.

[0049] The supply module 2 comprises a sieve 35 located below the metering device 33. The sieve 35 is connected to the outlet 331 of the metering device 33. This sieve makes it possible to filter out agglomerates of powder and to separate them from the rest of the powder in the receptacle 351. The sieve includes a third evacuation circuit 353 which may comprise a vacuum pump for generating a suction force.

[0050] The supply module 2 comprises a reservoir 37 located below the sieve 35. The reservoir 37 may be a hopper having a volume with a frusto-conical shape designed to store a large amount of production powder. The hopper may be oriented such that the axis of the frusto-conical shape is vertical and the frusto-conical volume has a smaller horizontal cross section at the bottom of the hopper. The reservoir 37 has an outlet 371 located at the bottom of the reservoir.

[0051] When the second door 291 is in an open position, powder can be transferred from the glove box 25 to the reservoir 37. The powder can then pass sequentially from the glove box 25 to the main hopper 29, the weighing device 33, the sieve 35 and then finally to the reservoir 37. In this way, a feed circuit can be defined that is configured to transfer powder located in the glove box 25 to the main hopper 29 or further to the reservoir 37. The second door 291, which defines a passage between the housing and the main hopper and which can be opened and closed in a controlled manner in a gas-tight manner, can open and close the feed circuit.

[0052] The providing module 2 comprises a dry inert gas supply system 36. The supply system 36 is capable of supplying a stream of dry inert gas in a duct 352 connected to the sieve 35. The stream of dry inert gas passing through the duct 352 is directed from bottom to top so as to encounter the powder passing through the sieve from bottom to top. The stream of inert gas that reaches the sieve 35 through the duct 352 also diffuses into the upper part of the reservoir 37.

[0053] The duct 352 and the third discharge circuit 353 may be aligned in one and the same direction such that a stream of inert gas can sequentially pass through the duct 352, encounter the powder passing through the sieve, and finally pass through the third discharge circuit 353 in one and the same direction.

[0054] The supply system 36 may also provide a stream of dry inert gas at the bottom of the reservoir 37 , for example at a duct 372 connected to the outlet 371 .

[0055] The outlet 371 of the reservoir is connected to a return circuit 391. The return circuit 391 connects the outlet 371 of the reservoir 37 to the inlet 211 of the suction system 21. The return circuit 391 connects the outlet 371 of the reservoir 37 to the housing 25. Powder can be transported from the reservoir 37 towards the powder housing 25 via the suction system 21. The suction system 21 can suck powder from the reservoir 37 towards the suction system 21 via the return circuit 391.

[0056] Furthermore, the outlet 371 of the reservoir is connected to a production duct 392. The production duct 392 connects the outlet 371 of the reservoir 37 to the production module 4, making it possible to transfer the powder contained in the reservoir 37 to the production module 4.

[0057] The sieve 35 is positioned directly 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 sent to the production module 4 .

[0058] The reservoir 37 may have a smaller volume than the main hopper 29. The role of the reservoir 37 is to store the powder just before it is transported to either the production module 4 or the suction system 21. The reservoir 37 may be called a buffer hopper.

[0059] The main hopper 29 is designed to accommodate the majority of the production powder required for the additive manufacturing of one or more three-dimensional objects. The powder accommodated in the main hopper 29 is intended to be transferred to a manufacturing module 4. To that end, the main hopper 29 is designed to be connected to a manufacturing module 4 configured to additively manufacture an object from the powder located in the main hopper 29. The main hopper 29 is connected to the manufacturing module by a metering device 33, a sieve 35, a reservoir or buffer hopper 37 and finally a circulation of powder through a manufacturing duct 392.

[0060] The delivery module 2 comprises a controller 39 making it possible to divert the powder from the outlet 371 into a return circuit 391 or into a production duct 392 .

[0061] The provision module 2 may comprise a moisture sensor 201 arranged on the first gas exhaust circuit 23. This moisture sensor 201 makes it possible to know the humidity level of the gas exhausted by the suction system 21, i.e. the humidity level upstream of the inlet 211 of the suction system 21.

[0062] The delivery module 2 may include a moisture sensor 202 located on top of the main hopper 29. This moisture sensor 202 allows the moisture level within the main hopper 29 to be known and can directly provide information regarding the moisture level of powder that may be present within the main hopper 29.

[0063] The supply module 2 may be equipped with a moisture sensor 203 connected to the dry inert gas supply system 36. This moisture sensor 203 makes it possible to know the moisture level of the dry inert gas delivered to the sieve 35 or to the reservoir 37.

[0064] The delivery module 2 comprises a circulation induction system including a suction system 21 .

[0065] The suction system 21 can draw powder from the reservoir 37 towards the suction system 21 via a return circuit 391 .

[0066] (Manufacturing Module) At its top, the manufacturing module 4 comprises a second suction system 41 connected to a fourth gas discharge circuit 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 a suction force at the inlet 411, which is directed towards the inside of the second suction system 41. The inlet 411 of the second suction system 41 is connected to the manufacturing duct 392. The fourth gas discharge circuit 43 can comprise a vacuum pump for generating the suction force. The second suction system 41 can comprise a powder filter so that no powder enters the fourth gas discharge circuit 43. The second suction device 41 comprises a device capable of separating the powder from the gas, for example a cyclone. Other devices for separating the powder from the gas exist, for example a filter chamber containing a filter, a cyclofilter or a discharge box. The second suction device 41 is designed to receive the additive manufacturing powder from the inlet 411 and store it. The stored powder is located at the bottom of the second suction device 41 and can be removed via the outlet 413 .

[0067] The production module 4 comprises an airlock 45 located below the second suction system 41. The airlock 45 allows the powder to be transferred without the printer chamber communicating with the second suction system 41, so as to avoid disruption of the printing enclosure in terms of inertization and pressure.

[0068] The fabrication module 4 includes a diverging screw 47 and a converging screw 51 located one on each side of an enclosure 49 in which the three-dimensional object is fabricated. The enclosure 49 is the printer chamber.

[0069] The production module 4 is equipped with a powder recovery system that recovers the dispersed and unsolidified powder at the end of production.

[0070] The recovery system may comprise a suction tube 53 designed to suck the powder. The suction tube 53 comprises a suction nozzle 533 constituting the inlet of the suction tube. The powder is sucked in at the nozzle and transferred to the other end of the tube constituting the outlet of the suction tube 53. The manufacturing machine 1 may comprise a first recovery duct 531 connecting the outlet of the suction tube 53 with the inlet 211 of the suction system 21.

[0071] The recovery system may comprise a redundant air lock 55 designed to recover the powder coming from the convergence screw 51 .

[0072] The manufacturing apparatus 1 may include a second recovery duct 551 connecting the excess airlock 55 with the inlet 211 of the suction system 21 .

[0073] The redundant airlock 55 allows the printer chamber to transfer powder without communicating with the second recovery duct 551, so as to avoid disruption of the printing enclosure in terms of inertization and pressure.

[0074] The manufacturing apparatus 1 may also comprise a second controller designed to circulate the powder in a controlled manner from the collection system towards the suction system 21. In this respect, the inlet 211 may be referred to as the inlet of the providing module 2, which inlet is connected to the manufacturing module 4 and is designed to receive the powder placed in the manufacturing module 4.

[0075] It should be noted that the manufacturing apparatus 1 is equipped with sufficient valves at the intersections of the ducts 391, 392, 531, 551 to allow for the circulation of the powders as described herein.

[0076] It should also be noted that it is possible to transfer powder 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, 30 configured in the extraction arrangement, and finally the glove box 25. More specifically, the powder reaching the glove box 25 can be funneled into a container accommodated in the glove box 25. Thus, there is an extraction circuit, distinct from the supply circuit, configured to transfer additive manufacturing powder from the inlet 211 of the providing module 2 to the container when the container is received in the glove box 25, the extraction circuit including the diverters 27, 30.

[0077] (Filling method) The delivery module 2 allows the filling and sieving of the production powder according to the steps described below. In the initial state, the housing 25 is hermetically closed, contains no container and the main hopper 29 and the reservoir 37 are empty of powder. The passage defined by the second door 291 between the housing and the main hopper is initially hermetically closed.

[0078] During a first step S1, the oxygen fraction inside the housing is adjusted to reach at least 18%. The oxygen sensor 257 obtains a measurement of the oxygen fraction inside the housing 25. Depending on the measurement, the air supply circuit 259 is operated to increase the oxygen fraction. The gas exhaust circuit 2513 is operated to substantially maintain atmospheric pressure inside the housing 25. By means of the oxygen sensor 257 it is possible to ensure that the oxygen fraction inside the housing is at least 18%.

[0079] During a second step S2, the door 253 of the housing 25 is opened and a container of powder is inserted or multiple containers of powder are inserted into the housing 25. The container can be placed in a passage area 255 of the housing 25.

[0080] During a third step S3, the door 253 of the housing 25 is closed and the oxygen fraction in the housing is adjusted to be less than 2%. The inert gas supply circuit 2511 is activated to reduce the oxygen fraction. The gas exhaust circuit 2513 is activated to substantially maintain atmospheric pressure in the housing 25. Reducing the oxygen fraction to less than 2% can be called inerting. The oxygen sensor 257 makes it possible to ensure that the oxygen fraction in the housing is less than 2%.

[0081] During a fourth step S4, the main hopper 29 is filled. The isolation door 291 is actuated to open the passage between the housing and the main hopper. The operator handles the entire container in the passage area 255 by means of the tool 251, opens the container and pours the contents of the container through the passage into the main hopper 29. For example, the operator puts on the glove box of the housing 25, grasps the entire container in the passage area 255, opens the container and pours the contents of the container through the passage into the main hopper 29. The operator puts the empty container back into the passage area 255 and proceeds in the same way until all containers in the housing are empty.

[0082] During a fifth step S5, the isolation door 291 is closed so as to hermetically close the passage between the housing and the main hopper.

[0083] During a sixth step S6, the oxygen fraction inside the housing is adjusted to reach at least 18%. The air supply circuit 259 is operated to increase the oxygen fraction. The gas exhaust circuit 2513 is operated to substantially maintain atmospheric pressure inside the housing 25. The oxygen sensor 257 makes it possible to ensure that the oxygen fraction in the housing is at least 18%.

[0084] During a seventh step S7, the door 253 of the housing 25 is opened and the empty container(s) of powder is removed from the housing 25.

[0085] During an eighth step S8, the door 253 of the housing 25 is hermetically closed.

[0086] During a ninth step S9, the powder is sieved and stored in a reservoir 37. The powder contained in the main hopper 29 is transferred via a weighing device 33 to a sieve 35. The sieve 35 sieves the powder and extracts excessively large powder lumps and agglomerates. These lumps are transferred to a receptacle 351 where they are stored. The sieved powder passes through the sieve 35 into a reservoir 37 where the powder is stored prior to use.

[0087] (How to transfer) The supply module 2 allows transferring unused production powder. The process for transferring unused powder initially located in the reservoir 37 is described according to the following steps. In the initial state, the housing 25 is hermetically closed, does not contain a container and the reservoir 37 contains unused powder. The passage defined by the isolation door 291 between the housing and the main hopper is initially hermetically closed.

[0088] Note 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 not sufficient to contain all of the unused powder.

[0089] During a first step E1, the oxygen fraction inside the housing is adjusted to reach at least 18%. The oxygen sensor 257 obtains a measurement value of the oxygen fraction inside the housing 25. Depending on the measurement value, the air supply circuit 259 is operated to increase the oxygen fraction. The gas exhaust circuit 2513 is operated to substantially maintain atmospheric pressure inside the housing 25. By means of the oxygen sensor 257 it is possible to ensure that the oxygen fraction inside the housing is at least 18%.

[0090] During a second step E2, the door 253 of the housing 25 is opened.

[0091] During a third step E3, an empty container is inserted or a number of empty containers are inserted into the housing 25. The container can be placed in the passage area 255 of the housing 25. Also, the container lid is inserted. The container can be introduced in an open state. In particular, if the container has an inert atmosphere, i.e. a gas composition of less than 2% oxygen and at least 98% inert gas, the container can be introduced in a closed state.

[0092] During a fourth step E4, the door 253 of the housing 25 is hermetically closed. During a fifth step E5, the oxygen fraction in the housing is adjusted to less than or equal to 2%. The inert gas supply circuit 2511 is activated to reduce the oxygen fraction.

[0093] The gas exhaust circuit 2513 is operated to maintain substantially atmospheric pressure within the housing 25. An oxygen sensor 257 makes it possible to ensure that the oxygen fraction within the housing is less than or equal to 2%.

[0094] During a sixth step E6, unused powder is transferred from the reservoir 37 or from 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 circuit 391.

[0095] An inert gas supply circuit 372 connected to the top and bottom of the reservoir is operated to admit unused powder to the return circuit 391. The suction system 21 is operated to generate a suction force at the inlet 211 that is directed towards the inside of the suction system 21. This operating setting can be according to a rich phase mode, a lean phase mode and various other possible transport modes. The powder concentration in the circulation duct and the velocity of the gas stream can be controlled for this purpose.

[0096] During a seventh step E7, a sequence of sub-steps is executed.

[0097] This sequence is performed by the diverter configured in the extraction configuration.

[0098] During a first substep E71, empty containers are moved from the passage area 255 below the weighing system into a transfer area.

[0099] During a second substep E72, the metering system 27 is activated to separate a predetermined amount of powder from the powder stored in the suction system 21. This amount is less than or equal to the maximum capacity of the container.

[0100] During a third substep E73, the metering system is activated to extract the powder, the position of the container allowing the powder to subsequently enter the container.

[0101] During a fourth substep E74, the container and its lid are handled using the tool 251 so as to close the container with the lid. The operator closes the container with the lid and places the filled container in the transition area.

[0102] If unused powder remains in the suction system and if an empty container remains in the transition area, the sequence of sub-steps is restarted. If the two conditions are met, the sequence is restarted and sub-steps E71, E72, E73 and E74 are carried out with a new empty container. If not, the sequence is interrupted and the eighth step E8 is carried out.

[0103] During an eighth step E8, the oxygen fraction inside the housing is adjusted to reach at least 18%. The air supply circuit 259 is operated to increase the oxygen fraction. The gas exhaust circuit 2513 is operated to substantially maintain atmospheric pressure inside the housing 25. By means of the oxygen sensor 257 it is possible to ensure that the oxygen fraction inside the housing is at least 18%.

[0104] During a ninth step E9, the door 253 of the housing 25 is opened.

[0105] During a first step E10, the filled and closed container or containers are removed from the housing 25.

[0106] During a first step E11, the door of the housing is hermetically closed.

[0107] The supply module 2 comprises both a housing 25 making it possible to fill a container of powder into a main hopper 29 , a suction system 21 , a metering system 27 , a main hopper, a powder metering device 33 , a powder sieve 35 and a reservoir 37 .

[0108] If there is still powder stored in the reservoir 37 when the manufacturing process is finished, the unused powder can be transported to the suction system 21 via the return circuit 391.

[0109] The presence of a housing downstream of the metering system then allows the transfer of unused powder from the suction system 21 to an empty container arranged in the housing. It is possible to transfer unused powder.

[0110] The unused powder can be repackaged into smaller portions than in the prior art, which portions, like the powder containers, are light enough to be handled and moved by an operator, and this repackaging can be performed under the atmosphere protected by the housing.

[0111] It should be noted that the metering system 27 and the bypass duct 31 allow the powder to be circulated either from the suction system to the housing 25 or to the main hopper 29. In this way, as in the prior art, it is possible to sieve unused powder from the production module 4 again before reuse, without transferring it. This is because the suction system 21 sucks in the unused powder, which can then pass directly to the main hopper 29 via the bypass conduit 31. The unused powder can then be sieved and stored in the reservoir 37.

[0112] (Method for transferring powder from a manufacturing module) In the transfer method described, unused powder is initially located in the reservoir 37 or main hopper 29 .

[0113] The provision module 2 is also capable of transferring unused production powder initially located in the production module 4, where it was transferred and then spread during the production process of the three-dimensional object. A part of the powder that is not solidified at the end of this process and that surrounds the production object is collected by a recovery system via a suction pipe 53, and another part of the unsolidified powder, called excess powder, is collected via a convergence screw and excess airlock.

[0114] In step P1, virgin powder is conveyed to the suction system 21. The powder is sucked by the suction system 21 and passes through the first recovery duct 531 or through the second recovery duct 551.

[0115] At the end of step P1, the unused powder is collected in the suction system 21.

[0116] If the unused powder is to be discarded, the transfer method continues with steps E7 to E11 described above.

[0117] If the virgin powder is to be reused later, it is desirable to sift the virgin powder again before decanting, in which case the decanting process includes the following steps:

[0118] During step P2, the virgin powder is transferred to the main hopper 29 and the diverters (27, 30) are configured in a loop-back configuration such that the virgin powder contained in the suction system 21 is conveyed to the bypass channel 31. The virgin powder then flows from the outlet 213 of the suction system 21 via the bypass channel 31 towards the main hopper 29.

[0119] During step P3, sieve 35 sieves out unused powder. The powder contained in main hopper 29 is transferred to sieve 35 via weighing device 33. Sieve 35 sieves the powder and extracts oversized powder lumps and agglomerates. These lumps are transferred to receptacle 351 where they are stored.

[0120] At the end of step P3, the sieved powder leaves the sieve 35 and enters the reservoir 37.

[0121] The remainder of the transfer method follows steps E1 to E11 already described above.

[0122] The presence of collection channels 531 and 551 allows the collection system to transport non-solidified powder collected in the production module 2 to the suction system 21. This powder can then be packaged in a small enough quantity to be moved by an operator, for example in a powder container.

[0123] The presence of a housing located downstream of the metering system then allows unused powder to be poured from the suction system 21 into an empty container located in the housing. The housing 25 located in this location allows the transfer of unused powder under a protective atmosphere. This use allows repackaging in quantities that can be transported by the operator under a protective atmosphere before being discarded.

[0124] It should be noted that this powder can be re-sieved before being transferred. The diverters 27, 30 make it possible to transport the powder from the suction system 21 through the bypass duct 31 to the main hopper 29. This unused powder can then be re-sieved by the sieve 35. The unused sieved powder is then returned to the suction system 21 through the return circuit 391. From the suction system 21, the powder can now be poured towards the housing 25 for repackaging, the diverters 27, 30 being configured in an extraction configuration. It is thus possible to repackage under a protective atmosphere an amount of powder that can be transported by the operator before storage for possible subsequent reuse.

Claims

1. A provision module (2) for supplying additive manufacturing powder, a main hopper (29) for storing additive manufacturing powder, the 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) connected to the production module (4) and designed to receive powder located in the production module (4); a glove box (25) designed to receive the container (28) and capable of being sealed and closed; a feed circuit configured to transfer powder located within the glove box (25) to the main hopper (29); A providing module (2) comprising: further comprising an extraction circuit distinct from the supply circuit, the extraction circuit being configured to transfer the additive manufacturing powder from the inlet (211) of the provision module (2) to the container (28) when the container (28) is received in the glove box (25); The glove box (25) includes a glove (251) that closes the container (28) when the container (28) is filled with powder while the glove box (25) is closed. A provision module (2).

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

3. a reservoir (37) connected to said main hopper (29), said reservoir (37) being located below said main hopper (29) and including an outlet (371) designed to be connected to said production module (4) by a production duct (392); a return circuit (391) configured to redirect additive manufacturing powder located in the reservoir (37) towards the inlet (211) of the provision module (2); a circulation induction system designed to draw powder from the outlet (371) of the reservoir (37) to the inlet (211) of the supply module (2); Equipped with A provision module (2) according to claim 1 or 2.

4. the extraction circuit comprises a diverter (27, 30); the supply module (2) further comprises a bypass circuit (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 bypass circuit (31) an extraction arrangement in which additively manufactured powder coming from an inlet (211) of the provision module (2) is selectively redirected towards the glove box (25); a loop-back configuration in which additive manufacturing powder coming from an inlet (211) of the providing module is selectively redirected to the bypass circuit; The diverter (27, 30) may be configured as A provision module (2) according to claim 3.

5. An additive manufacturing apparatus (1), comprising: A provision module (2) for providing an additively manufactured powder according to one of claims 1 to 4, a manufacturing module (4) configured to additively manufacture an object from the powder located in the main hopper (29); Equipped with An additive manufacturing apparatus (1), wherein the main hopper (29) is connected to the manufacturing module (4) and the inlet (211) of the providing module (2) is connected to the manufacturing module (4).

6. a recovery system (53, 55) for recovering powder that does not solidify when the object is being additively manufactured and for redirecting the recovered powder towards an inlet (211) of the delivery module (2). Additive manufacturing device (1) according to claim 5.

7. A method for transferring additive manufacturing powder using a provision module (2) according to one of claims 1 to 4 or a device according to any of claims 5 and 6, comprising: Inserting (E3) an empty container into said glove box (25) and then sealingly closing (E4) said glove box (25); Once said container is filled with additive manufacturing powder transferred from an inlet (211) of said provision module (2), handling said container (E74) to close said container while closing said glove box (25); Including, How to transfer.

8. and a step (E6) of conveying said powder from said reservoir (37) to an inlet (211) of said supply module (2), 8. A method according to claim 7, using a provision module (2) according to claim 3 or 4.

9. 9. A method for transferring additively manufactured powder according to claim 8 using an apparatus according to claim 6, comprising a step (P1) of transporting powder from the collection system (53, 55) to an inlet (211) of the provision module (2).

10. 10. The method for additively manufactured powder transfer according to one of claims 7 to 9, comprising a pre-powder sieving step (P3).

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