IRONING CHAMBER FOR METAL-BASED 3D PRINTING AND METAL-BASED 3D PRINTING FACILITY

Abstract

TITLE OF THE INVENTION: INERTING CHAMBER FOR METAL-BASED 3D PRINTING AND METAL-BASED 3D PRINTING INSTALLATION An inerting chamber for metal-based 3D printing comprises an enclosure (2) for containing an inert gaseous medium in which to perform the 3D printing, the enclosure comprising: - at least one first access opening (10), the inerting chamber comprising a first sealed connection (12) at least partially deformable which is hermetically attachable to a robot (103) partially engaged inside the enclosure through the first access opening and which is hermetically attached to the enclosure at the level of the first access opening, and - at least one second access opening (14),the inerting chamber comprising a second sealed connection (16) at least partially deformable which is hermetically sealable to a positioner (105) partially engaged inside the enclosure through the second access opening and which is hermetically sealable to the enclosure at the level of the second access opening. Figure for the abbreviation: Figure 7,

Description

Title of the invention: IRONING CHAMBER FOR METAL-BASED 3D PRINTING AND METAL-BASED 3D PRINTING INSTALLATION Technical field of the invention

[0001] The invention relates to an inerting chamber for metal-based 3D printing and a metal-based 3D printing installation. State of the art

[0002] Certain 3D printing techniques allow for the production of metal parts. In these 3D printing techniques, the metal material is added progressively in successive layers or point by point. At the very moment it is added locally to a portion of a part already produced, the metal material is very hot and in a liquid state, having received a concentrated amount of energy for this purpose, for example from a laser. As a result, the metal material readily combines with oxygen, for example from atmospheric air, at the moment it is added.

[0003] To avoid metallic oxidation of the metallic material during its deposition when its state and temperature make it particularly oxidizable, 3D printing is done in an inert gaseous medium.

[0004] It is known to perform metal-based 3D printing in a chamber containing an inert gaseous medium. A 3D printing robot and a positioner are placed entirely within this chamber. The 3D printing robot performs the 3D printing, which progressively forms the part on the positioner, which orients the part as it is being printed.

[0005] The room containing the inert gaseous medium has significant dimensions, thanks to which it is able to contain the 3D printing robot and the positioner.

[0006] However, filling a large volume with an inert gaseous medium is costly. Maintaining an inert gaseous medium in a large volume is also costly. Summary of the invention

[0007] An inerting chamber for metal-based 3D printing comprises an enclosure for containing an inert gaseous medium in which the 3D printing is performed. The enclosure has at least one access opening. A leak-proof, at least partially deformable fitting is hermetically sealed to a robot partially inserted inside the enclosure through the access opening. The leak-proof fitting is hermetically sealed to the enclosure so as to be in communication with the access opening. Brief description of the figures

[0008] Other advantages and features will become clearer from the following description of a particular embodiment of the invention, given by way of non-limiting example and shown in the accompanying drawings, among which:

[0009] [Fig-1] is a perspective view of an inerting chamber according to a mode of realization of the invention,

[0010] [Fig.2] is a cross-sectional view along plane II of [Fig.1],

[0011] [Fig.3] is a perspective view of a first watertight fitting constituting the inerting chamber visible in figures 1 and 2,

[0012] [Fig.4] is an axial section which shows the same first watertight connection as [Fig.2], as well as assembly devices,

[0013] [Fig.5] is seen in perspective of a second sealed connection constituting the inerting chamber visible in figures 1 and 2,

[0014] [Fig.6] is an axial section which shows the same second sealing connection as [Fig.5], as well as assembly devices,

[0015] [Fig.7] is an elevational view of a 3D printing installation according to an embodiment of the invention, and

[0016] [Fig.8] is a detailed, cross-sectional view, which represents part of the 3D printing installation visible in [Fig.7]. Description of the implementation methods

[0017] In figures 1 and 2, an inerting chamber 1 according to an embodiment of the invention is an inerting chamber for a metal-based 3D printing.

[0018] The inerting chamber 1 comprises an enclosure 2, which is mounted on a mobile chassis 3 carried by several wheels 4. The enclosure 2 carries an entry / exit airlock 5 comprising two successive doors 6.

[0019] The enclosure 2 has several access openings, among which are the access openings 8 which can be closed by hatches 9 or equipped with waterproof gloves not shown.

[0020] Among the access openings of enclosure 2, the access opening referenced 10 is a first access opening provided with a sealed connection, which is the sealed connection 12. The sealed connection 12 is a first gas-tight connection.

[0021] Among the access openings of enclosure 2, a second access opening equipped with a sealed connection is visible and referenced as 14 in [Fig.2]. The sealed connection equipping this access opening 14 is referenced as 16. This is a second gas-tight connection.

[0022] The watertight fitting 12 is shown alone in [Fig.3]. The watertight fitting 12 has an inlet 18, an outlet 20, and a deformable portion 22 which connects the inlet 18 to the outlet 20.

[0023] The deformable portion 22 is in the shape of a conduit and delimits a passage 24 which is a through passage connecting the inlet 18 and the outlet 20 with each other.

[0024] At its inlet 18, the watertight fitting 12 has an inlet flange 26, which is directed inwards, i.e. towards the passage 24. At its outlet 20, the watertight fitting 12 has an outlet flange 28, which is directed outwards, i.e. in the opposite direction to the passage 24.

[0025] The deformable portion 22 is constructed as a flexible membrane. The deformable portion 22 has a cross-section that increases continuously from the inlet 18, such that any annular segment of the deformable portion 22 can pass into another annular segment of the deformable portion 22 as long as it is closer to the inlet 18 than that other annular segment. In this way, the deformable portion 22 can be partially inverted, as shown in [Fig. 4], when the inlet 18 of the watertight fitting 12 and the outlet 20 of the watertight fitting 12 are brought closer together.

[0026] In the embodiment shown, the entire deformable portion 22 from the inlet 18 to the outlet 20 is a flaring portion with an increasing cross-section. According to an alternative embodiment not shown, only a part of the deformable portion 22 is a flaring portion such that a first annular segment of the flaring portion can pass into a second annular segment of the flaring portion when the inlet 18 of the watertight fitting 12 and the outlet 20 of the watertight fitting 12 are brought close to each other.

[0027] In some embodiments, the watertight fitting 12 is made of a transparent material. In some embodiments, the watertight fitting 12 is made of a UV-resistant material. In some embodiments, the watertight fitting 12 is made of polyvinyl chloride (also known by the acronym PVC for "Polyvinyl chloride," which in English refers to what polyvinyl chloride refers to in French).

[0028] As can be seen in [Fig. 4], a ring 30 and an annular portion of the enclosure 2 are tightened against each other by screws 34. The ring 30 and the annular portion of the enclosure 2 tighten the outlet flange 28 together so that a gas seal is achieved between the sealed fitting 12 and the enclosure 2 at the outlet 20 of the sealed fitting 12. The outlet 20 of the sealed fitting 12 is thus hermetically attached to the enclosure 2 so as to be in communication with the access opening 10.

[0029] As can be seen in [Fig. 4], a ring 36 and a ring 38 are clamped together by screws 39. The ring 38 is part of a movable robot arm 40 visible in [Fig. 7], where this movable robot arm 40 is partially engaged inside the enclosure 2 through the access opening 10. The rings 36 and 38 clamp the inlet flange 26 together so that a gas seal is achieved between the sealed fitting 12 and the movable robot arm 40 at the inlet 18 of the sealed fitting 12. The inlet 18 of the sealed fitting 12 is thus hermetically sealed to the movable robot arm 40, which is partially engaged inside the enclosure 2 through the access opening 10.

[0030] The watertight fitting 16 is shown alone in [Fig. 5]. The watertight fitting 16 has an outlet 48, an inlet 50, and a deformable portion 52 which connects the outlet 48 to the inlet 50.

[0031] The deformable portion 52 is in the shape of a conduit and delimits a passage 54 which is a through passage connecting the outlet 48 and the inlet 50 with each other.

[0032] At its outlet 48, the watertight fitting 16 has an outlet flange 56, which is directed outwards, i.e. in the opposite direction to the passage 54. At its inlet 50, the watertight fitting 16 has an inlet flange 58, which is directed inwards, i.e. towards the passage 54.

[0033] The deformable portion 52 is constructed as a flexible membrane. The deformable portion 52 has a cross-section that increases continuously from the inlet 50, such that any annular segment of the deformable portion 52 can pass into another annular segment of the deformable portion 52 as soon as it is closer to the inlet 50 than that other annular segment. In this way, the deformable portion 52 can be partially reversed, as is the case in [Fig. 6], when the outlet 48 of the watertight fitting 16 and the inlet 50 of the watertight fitting 16 are brought closer together.

[0034] In the embodiment shown, the entire deformable portion 52 from the inlet 50 to the outlet 48 is a flaring portion with an increasing cross-section. According to an alternative embodiment not shown, only a part of the deformable portion 52 is a flaring portion such that a first annular segment of the flaring portion is able to pass into a second annular segment of the flaring portion when the inlet 50 of the watertight fitting 16 and the outlet 48 of the watertight fitting 16 are brought close to each other.

[0035] In some embodiments, the watertight fitting 16 is made of a transparent material. In some embodiments, the watertight fitting 16 is made of a UV-resistant material. In some embodiments, the watertight fitting 16 is made of polyvinyl chloride (also referred to by the acronym PVC for "Polyvinyl chloride", which in English means what polyvinyl chloride means in French).

[0036] As can be seen in [Fig. 6], a ring 60 and an annular portion of the enclosure 2 are clamped together by screws 64. The ring 60 and the annular portion of the enclosure 2 clamp the outlet flange 56 together so that a gas seal is achieved between the sealed fitting 16 and the enclosure 2 at the outlet 48 of the sealed fitting 16. The outlet 48 of the sealed fitting 16 is thus attached in a hermetic manner to the enclosure 2 so as to be in communication with the access opening 14.

[0037] As can be seen in [Fig. 6], a ring 66 and a ring 68 are clamped together by screws 69. The ring 68 is part of a hinged support head 115 visible in [Fig. 2], where a positioner 105 comprising this hinged support head 115 is partially engaged inside the enclosure 2 through the access opening 14. The rings 66 and 68 clamp the inlet flange 58 together so that a gas seal is achieved between the sealed fitting 16 and the hinged support head 115 at the inlet 50 of the sealed fitting 16. The inlet 50 of the sealed fitting 16 is thus hermetically sealed to the hinged support head 115, which is partially engaged inside the enclosure 2 through the access opening 14.

[0038] In [Fig.7], a metal-based 3D printing installation is a 3D printing installation 101 according to an embodiment of the invention.

[0039] The 3D printing installation 101 includes the inerting chamber 1, a 3D printing robot 103, and the positioner 105. Like the 3D printing robot 103, the positioner 105 is a robot.

[0040] The 3D printing robot 103 is a known six-axis robot per se. It includes the robot's movable arm 40, which is an articulated arm.

[0041] As can be seen in [Fig.8], the movable robot arm 40 is partially engaged inside the enclosure 2 through the access opening 10.

[0042] At its distal end, the movable robot arm 40 has an articulated head, which is a metal-based 3D printing head such as a torch head 107 capable of performing metal-based 3D printing.

[0043] During the manufacturing of a part by 3D printing, the torch head 107 performs numerous movements made possible by the sealing connection 12. Among the movements made possible by the sealing connection 12 are upward movements of the torch head 107, downward movements of the torch head 107, lateral movements of the torch head 107 in any direction in a horizontal plane, and rotations of the torch head 107 around a first axis, a second axis not parallel to the first axis, and / or a third non-parallel axis. to the first and second axes, as well as movements composed of at least two movements from this list.

[0044] Also called "additive manufacturing," 3D printing refers to several techniques known in themselves, in which three-dimensional parts are produced by successive additions of material, for example, in the form of successive layers or point by point. As used here and in the attached claims, metal-based 3D printing is 3D printing in which the material added by successive additions to produce a part comprises at least one metal. For example, the material added by successive additions by the robot's movable arm 40 and its torch head 107 is or comprises a metal selected from chromium and titanium.

[0045] In the embodiment shown, the movable robot arm 40 and its torch head 107 are able to perform 3D printing according to the technique known per se and called "deposition under concentrated energy" (and called "Direct Energy Deposition" in English or DMD, its acronym).

[0046] The torch head 107 includes a guide 109 for feeding a strip of material 111, as well as a laser 113 capable of producing and directing a laser beam onto a localized area where the guide 109 is able to position the lower end of the strip of material 111.

[0047] According to one embodiment of the invention, the movable robot arm 40 and its torch head 107 are able to perform 3D printing according to powder bed fusion (called "Powder Bed Fusion" in English), selective laser sintering (called "Selective Laser Sintering" in English or "SLS", its acronym) or electron beam melting (called "Electron Beam Melting" in English or "EBM", its acronym).

[0048] The positioner 105 is known in itself. As can be seen in [Fig.2], the positioner 105 is partially engaged inside the enclosure 2 through the access opening 14.

[0049] During the manufacture of a part by 3D printing, the articulated support head 115 performs many movements made possible by the sealing connection 16. Among the movements made possible by the sealing connection 16 are the rotations of the articulated support head 115 around a fourth axis and / or a fifth axis not parallel to the fourth axis.

[0050] During the manufacture of a part by 3D printing, the articulated support head 115 carries this part and is able to change its orientation.

[0051] The inerting chamber includes a control and command system 117 for the chemical composition of the inert gaseous medium inside the enclosure 2. Known per se, the control and command system 17 is schematically represented in [Fig.7].

[0052] During the manufacturing of a part by 3D printing using the 3D printing installation 101, the enclosure 2 is generally gas-tight and is filled with an inert gaseous medium. For example, the inert gaseous medium in the enclosure 2 is argon gas, helium gas, nitrogen gas, or a mixture of two of these gases.

[0053] The inert gaseous medium inside the enclosure 2 contains neither oxygen nor water, or only infinitesimal traces. Thanks to this, the metal(s) in the material of the strip 111 are protected from a chemical reaction with oxygen and / or water during its or their melting due to the supply of a concentrated amount of energy by the laser beam produced by the laser 113. Description of the invention

[0054] The invention has at least the aim of making it possible to reduce the cost of metal-based 3D printing in an inert medium.

[0055] According to the invention, this objective is achieved by means of an inerting chamber for metal-based 3D printing, which comprises an enclosure for containing an inert gaseous medium in which the 3D printing is carried out, the enclosure comprising

[0056] - at least one first access opening, the inerting chamber comprising a first watertight connection, at least partially deformable, which can be hermetically attached to a robot partially engaged inside the enclosure through the first access opening and which is hermetically attached to the enclosure at the level of the first access opening, and

[0057] - at least one second access opening, the inerting chamber comprising a second watertight fitting at least partially deformable which can be attached in a watertight manner to a positioner partially engaged inside the enclosure through the second access opening and which is attached in a watertight manner to the enclosure at the level of the second access opening.

[0058] Thanks to the first access opening and the first airtight connection, a robot, such as a 3D printing robot, can be partially inserted into the inert gaseous environment chamber through the first access opening, while remaining partially outside the chamber. The first airtight connection creates a leak-proof seal between the chamber and the robot. Furthermore, thanks to the second access opening and the second airtight connection, a positioner partially inserted into the chamber can be positioned below a 3D printing head of a robot that is also partially inserted into the chamber.

[0059] The invention therefore makes it possible for a metal-based 3D printing to take place in a small enclosure containing a small volume of inert gaseous medium.

[0060] Reducing the volume of the inert gaseous medium in which metal-based 3D printing takes place leads to savings resulting from lower medium consumption inert gas, faster filling of the enclosure and / or lower cost to maintain inert gaseous medium in the enclosure.

[0061] The invention has a first advantage, which is to allow rapid filling of the enclosure with an inert gaseous medium, by allowing the internal volume of the enclosure to be small.

[0062] The invention has a second advantage, which is to more easily maintain inertness in a gaseous medium where metal-based 3D printing takes place. This second advantage is achieved by allowing the internal volume of the enclosure to be small.

[0063] The inerting chamber defined above may have one or more other advantageous characteristics, alone or in combination, in particular among those defined below.

[0064] In embodiments, at least one watertight connection comprises: - an inlet that can be hermetically attached to a robot partially engaged inside the enclosure through said access opening, - an outlet that is hermetically attached to the enclosure so as to be in communication with the first access opening, and - a deformable portion having a conduit shape delimiting at least partially a passage which connects the inlet of the watertight fitting and the outlet of the watertight fitting with each other.

[0065] Thus, the part of the robot passing through the first access opening, and / or the part of the positioner passing through the second access opening, can be moved relative to the enclosure by easily deforming the deformable part of the watertight fitting. This easy deformation can be a simple bending of the deformable part of the watertight fitting, with little or no elastic stretching of the deformable part of the watertight fitting.

[0066] In embodiments, at least one deformable portion includes a flared portion such that a first annular segment of the flared portion is able to pass into a second annular segment of the flared portion when the inlet and outlet of the watertight fitting are brought close together. Thus, the part of the robot passing through the first access opening, and / or the part of the positioner passing through the second access opening, can be moved relative to the enclosure by means of at least a partial reversal of the flared portion of the watertight fitting.

[0067] In some embodiments, at least part of the deformable portion is a flexible membrane. Thus, the part of the robot passing through the first access opening, and / or the part of the positioner passing through the second access opening, can be moved relative to the enclosure by easily deforming the deformable part of the watertight connection.

[0068] In some embodiments, the outlet of at least one watertight fitting has a clamped outlet flange such that a seal is achieved between this watertight fitting and the enclosure at the outlet of this watertight fitting. Thus, a seal can be easily achieved at the outlet of this watertight fitting.

[0069] In some embodiments, the outlet flange is elastically deformable at least in the direction of its thickness. Thus, the outlet flange is able to form a sealing gasket itself when two elements clamp it together.

[0070] In some embodiments, the outlet flange is tightened onto an added sealing gasket.

[0071] In some embodiments, the inlet of at least one watertight fitting has an inlet flange that can be tightened so as to create a seal at the inlet of that watertight fitting. Thus, a seal can be easily achieved at the inlet of that watertight fitting.

[0072] In some embodiments, the inlet flange is elastically deformable at least in the direction of its thickness. Thus, the inlet flange is able to form a sealing gasket itself when two elements clamp it together.

[0073] In some embodiments, the inlet flange is tightened onto an added sealing gasket.

[0074] In some embodiments, the first access opening is a top opening providing access to the inside of the enclosure from above, and the second access opening is a bottom opening providing access to the inside of the enclosure from below. Thus, a positioner partially engaged inside the enclosure can be positioned below a 3D printing head of a robot that is also partially engaged inside the enclosure.

[0075] In some embodiments, the inerting chamber includes a system for controlling and regulating the chemical composition of the inert gaseous medium inside the chamber,

[0076] The invention also relates to a metal-based 3D printing installation, which includes an inerting chamber as defined above, and a 3D printing robot comprising a movable robot arm partially engaged inside the enclosure through the first access opening, the first sealing fitting providing a watertight seal between the enclosure and the movable robot arm by allowing at least one type of movement of the movable robot arm relative to the enclosure, and a positioner partially engaged inside the enclosure through the second access opening, the second sealing fitting providing a watertight seal between the enclosure and the positioner.

[0077] In embodiments, the movable robot arm comprises, at its distal end, a torch head, which includes a guide for feeding a strip of material and a laser capable of directing a laser beam onto a localized area where the guide is able to position the lower end of the material strip.

Claims

Demands

1. Inerting chamber for a metal-based 3D print, characterized in that it comprises an enclosure (2) for containing an inert gaseous medium in which to carry out the 3D print, the enclosure comprising: - at least one first access opening (10), the inerting chamber comprising a first sealed fitting (12) at least partially deformable which is hermetically attachable to a robot (103) partially engaged inside the enclosure through the first access opening and which is hermetically attached to the enclosure at the level of the first access opening, and - at least one second access opening (14), the inerting chamber comprising a second sealed fitting (16) at least partially deformable which is hermetically attachable to a positioner (105) partially engaged inside the enclosure through the second access opening and which is hermetically attached to the enclosure at the level of the second access opening.

2. Inerting chamber according to claim 1, in which at least one said sealed fitting (12, 16) comprises: - an inlet (18, 50) that can be hermetically attached to a robot (103, 105) partially engaged inside the enclosure through said access opening (10, 14), - an outlet (20, 48) that is hermetically attached to the enclosure so as to be in communication with said access opening (10, 14), and - a deformable portion (22, 52) having a conduit shape that at least partially delimits a passage (24, 54) that connects the inlet (18, 50) of this sealed fitting (12, 16) and the outlet (20, 48) of this sealed fitting (12, 16) with each other.

3. Inerting chamber according to claim 2, in which the deformable portion (22, 52) has a flaring portion such that a first annular segment of the flaring portion is able to pass into a second annular segment of the flaring portion when the inlet (18, 50) of this sealed fitting (12, 16) and the outlet (20, 48) of this sealed fitting (12, 16) are brought close together.

4. Inerting chamber according to any one of claims 2 and 3, wherein at least a part of the deformable portion (22, 52) is a flexible membrane.

5. Inerting chamber according to any one of claims 2 to 4, wherein the outlet (20, 48) of at least one sealed fitting (12, 16) has an outlet flange (28, 56) tightened so that a seal is achieved between the sealed fitting (12, 16) and the enclosure (2) at the outlet (20, 48) of the sealed fitting (12, 16).

6. Inerting chamber according to any one of claims 2 to 5, in which the inlet (18, 50) of at least one sealed fitting (12, 16) has an inlet flange (26, 58) capable of being tightened so that a seal is achieved at the inlet (18, 50) of this sealed fitting (12, 16).

7. Inerting chamber according to any one of claims 1 to 6, wherein the first access opening (10) is a top opening giving access to the interior of the enclosure (2) from above, the second access opening (14) being a bottom opening giving access to the interior of the enclosure (2) from below.

8. Metal-based 3D printing installation, characterized in that it comprises an inerting chamber (1) according to any one of claims 1 to 7, and a 3D printing robot (103) comprising a movable robot arm (40) partially engaged inside the enclosure (2) through the first access opening (10), the first sealing fitting (12) providing a watertight seal between the enclosure and the movable robot arm by allowing at least one type of movement of the movable robot arm relative to the enclosure and a positioner (105) partially engaged inside the enclosure through the second access opening (14), the second sealing fitting (16) providing a watertight seal between the enclosure and the positioner.

9. A 3D printing installation according to claim 8, wherein the movable robot arm (40) has, at its distal end, a torch head (107), which includes a guide (109) for feeding a strip of material (111) and a laser (113) capable of directing a laser beam onto a localized area where the guide is able to position the lower end of the strip of material.

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