Welding device including an anti-contamination hood

Abstract

Title: Welding device comprising an anti-contamination hood Welding device (1) arranged to carry out welding between them of at least two parts to be welded (2), the welding device comprising: a welding unit (3) arranged to carry out welding along the junction (4) of two parts to be welded, generating a weld pool (5) at a welding zone (10). an anti-contamination hood (6) arranged to be placed, in particular mobile, in contact with the parts to be welded (2) so that the welding unit (3) and the anti-contamination hood (6) encompass the entire weld pool (5) and so that any half-line (7) starting from the weld pool intersects either the anti-contamination hood or the welding unit, the welding device (1) being arranged in particular to move the welding zone (10) relative to the parts to be welded during welding. Figure for abstract: Fig. 1

Description

Title of the invention: Welding device comprising an anti-contamination hood

[0001] The present invention relates to a welding device comprising an anti-contamination hood, in particular for operation in space.

[0002] Welding is a process for joining elements. In space, under vacuum conditions, structures are most often assembled by mechanical docking interfaces such as latches.

[0003] However, welding may be considered for future construction of structures in space.

[0004] The use of welding requires the management of contamination created during the operation, such as welding ejecta or metal vapors.

[0005] This is the case, for example, when using arc or laser welding, or electron beam welding.

[0006] For use in space, the problem of collecting welding ejecta is crucial, because uncollected ejecta could become space debris dangerous for the host system and all space vehicles.

[0007] Furthermore, the metal vapors generated in the weld pool can interfere with the energy beam, altering the quality of the welding and generating defects in the assembly of the elements, or even come to be deposited on critical surfaces of the satellite, rendering it inoperative.

[0008] The invention aims to propose a solution to be able to limit contamination of the external environment during the welding process.

[0009] The invention relates to a welding device arranged to carry out welding between them of at least two parts to be welded, the welding device comprising: - a welding unit arranged to carry out welding along the junction of two parts to be welded, generating a weld pool at a welding zone, - an anti-contamination hood arranged to be placed, in particular mobile, in contact with the parts to be welded so that the welding unit and the anti-contamination hood encompass the entire weld pool and that any half-line starting from the weld pool intersects either the anti-contamination hood or the welding unit, the welding device being arranged in particular to move the welding zone relative to the parts to be welded during welding.

[0010] According to one aspect of the invention, the welding device is arranged to perform a welding together at least two parts to be welded dynamically, i.e. in such a way that the weld zone moves along the junction between the parts to be welded during welding.

[0011] According to one aspect of the invention, an ejecta which is expelled from the weld pool and which follows a straight line trajectory is stopped by the anti-contamination hood or the welding unit or the parts to be welded. Thus the ejecta cannot exit in a straight line from the volume defined by the hood, the welding unit and the parts to be welded.

[0012] A main axis of the welding unit is defined.

[0013] According to one aspect of the invention, the main axis of the welding unit is for example: - in the case of arc welding, the main axis of the welding electrode, - in the case of laser welding, the main axis of the laser beam, - in the case of electron beam welding, the main axis of the beam of electrons;

[0014] At each instant of the weld, the weld zone is called the intersection between the main axis of the welding unit and the surface of at least one part to be welded.

[0015] At each instant of the welding, the working distance is defined as the distance between the welding unit and the parts to be welded along the main axis of the welding unit, or the distance between the welding unit and the welding zone along the main axis of the welding unit.

[0016] At each instant of the welding, the angle formed between the main axis of the welding unit and the parts to be welded is noted a.

[0017] The angle a is defined in particular as the angle between the main axis of the welding unit and the plane tangent to the surface of the parts to be welded at the welding zone.

[0018] According to one aspect of the invention, the welding unit is an electron beam gun, arranged to cause the fusion of the parts to be welded by the emission of an electron beam striking the surface of the parts to be welded at the welding zone.

[0019] Alternatively, the welding unit may be a resistance welding device, or an arc welding device, or a laser welding device.

[0020] According to one aspect of the invention, the welding device is arranged to be used in space, under vacuum conditions.

[0021] According to one aspect of the invention, the welding device is in particular arranged for the assembly of structures in space.

[0022] According to one aspect of the invention, the welding unit is arranged to perform a weld generating a weld pool at the weld zone.

[0023] According to one aspect of the invention, the parts to be welded are flat.

[0024] Alternatively, the parts to be welded may be of any other shape, in particular curved or tubular.

[0025] According to one aspect of the invention, the anti-contamination hood is maintained in contact with at least one part to be welded during at least part of the welding.

[0026] In particular, the anti-contamination hood is kept in contact with at least one part to be welded throughout the entire welding operation.

[0027] According to one aspect of the invention, the welding unit and the anti-contamination hood encompass the entire weld pool without encompassing all of the parts to be welded.

[0028] According to one aspect of the invention, the anti-contamination cover is formed from a single piece.

[0029] Alternatively, the anti-contamination hood is formed from several parts secured to each other, these different parts being able to be formed from different materials.

[0030] According to one aspect of the invention, the anti-contamination cover comprises at least one part made of heat-resistant material, for example stainless steel.

[0031] According to one aspect of the invention, the anti-contamination cover comprises at least one part made of flexible material, for example a polymer.

[0032] Advantageously, the use of a flexible material makes it possible to keep the anti-contamination cover in contact with a non-smooth surface.

[0033] According to one aspect of the invention, the anti-contamination hood comprises: - an anti-contamination skirt, - an anti-contamination envelope.

[0034] According to one aspect of the invention, the anti-contamination envelope is tubular in shape.

[0035] Alternatively, the envelope may be of any other shape, in particular conical or curved.

[0036] According to one aspect of the invention, the anti-contamination skirt is formed from a flexible material with a low coefficient of friction, for example polymers.

[0037] According to one aspect of the invention, the anti-contamination envelope is fixed to the welding unit.

[0038] According to one aspect of the invention, the anti-contamination skirt is fixed on the anti-contamination envelope to form the anti-contamination hood.

[0039] According to one aspect of the invention, the anti-contamination envelope and the welding unit and the anti-contamination skirt are assembled irreversibly.

[0040] Alternatively, the welding unit, the anti-contamination jacket and / or the anti-contamination skirt are assembled in a reversible manner, so as to allow the replacement of the anti-contamination skirt and / or the anti-contamination jacket without damaging the parts.

[0041] According to one aspect of the invention, the anti-contamination hood is hermetic, that is to say forms with the parts to be welded and the welding unit a hermetic space. tically closed.

[0042] According to one aspect of the invention, the welding device comprises a vacuum pump connected to the hermetically sealed space formed by the anti-contamination hood and the parts to be welded, and arranged for the evacuation of metal vapors.

[0043] Alternatively, the anti-contamination hood comprises at least one orifice arranged for the evacuation of welding vapors.

[0044] Advantageously, the use of an anti-contamination hood comprising at least one orifice makes it possible to avoid an accumulation of metal vapors inside the anti-contamination hood.

[0045] According to one aspect of the invention, the anti-contamination cover comprises at least one part made of a porous material.

[0046] According to one aspect of the invention, the anti-contamination envelope is made of a porous material.

[0047] For example, the anti-contamination envelope comprises a metal foam or a lattice structure.

[0048] Alternatively, the anti-contamination envelope comprises a plurality of porous layers, for example by a plurality of perforated plates.

[0049] According to one aspect of the invention, the anti-contamination hood comprises at least one evacuation channel.

[0050] According to one aspect of the invention, the discharge channels comprise one end placed close to the weld pool generated by the welding unit, and one end connected to an orifice of the anti-contamination hood.

[0051] According to one aspect of the invention, the discharge channels are arranged for the circulation of welding vapors from the welding bath to the outside of the anti-contamination hood.

[0052] Alternatively, the discharge channels comprise one end placed close to the solder bath generated by the soldering unit, and one end connected to the vacuum pump, and are arranged for the circulation of solder vapors from the solder bath to the vacuum pump.

[0053] According to one aspect of the invention, the anti-contamination hood comprises a protective shield.

[0054] According to one aspect of the invention, the protective shield is arranged inside the anti-contamination hood.

[0055] According to one aspect of the invention, the protective shield is placed around the main axis of the welding unit, and is arranged to limit the presence of weld ejecta and weld vapors along the main axis of the welding unit.

[0056] In particular, the protective shield is arranged to minimize, in a plane normal to the main axis of the welding unit, the passage surface that ejecta emitted by the weld pool and moving in a straight line could cross to reach the welding unit.

[0057] This passage surface minimized by the protective shield also influences the flow of metal vapors which can propagate along the main axis of the welding unit and which can disrupt the welding.

[0058] In the case of laser welding or electron beam welding, the protective shield thus advantageously makes it possible to limit the disturbance of the beam by vapors or ejecta which could alter the quality of the weld.

[0059] According to one aspect of the invention, the protective shield is tubular in shape.

[0060] Alternatively, the protective shield is planar in shape, and forms a pierced disc allowing the passage of an electron beam or a laser along the main axis of the welding unit.

[0061] Alternatively, the protective shield comprises a layered structure.

[0062] According to one aspect of the invention, the evacuation channels are formed between the layers of the protective shield.

[0063] Alternatively, the discharge channels are tubular in shape.

[0064] According to one aspect of the invention, the protective shield may be formed in one piece with the anti-contamination envelope.

[0065] Alternatively, the protective shield and the anti-contamination envelope may be two separate parts.

[0066] According to one aspect of the invention, the evacuation channels are formed as a unit with the anti-contamination envelope or with the protective shield.

[0067] Alternatively, the exhaust channels are separate parts.

[0068] According to one aspect of the invention, the anti-contamination hood comprises a welding vapor capture zone.

[0069] According to one aspect of the invention, the welding vapor capture zone is of domed shape, in particular is a dome.

[0070] According to one aspect of the invention, the welding vapor capture zone may be formed by the anti-contamination skirt, by the anti-contamination envelope, by an evacuation channel or by the protective shield.

[0071] According to one aspect of the invention, the welding vapor capture zone is placed vertically to the welding zone, i.e. opposite the surface of the parts to be welded.

[0072] According to one aspect of the invention, the welding vapor capture zone is arranged to allow condensation of the welding vapors on the walls of the anti-contamination hood.

[0073] According to one aspect of the invention, the welding creates a pressure differential, with a high pressure close to the weld pool, and a negative gradient away from the weld pool. This pressure differential causes the displacement of weld vapors from the weld pool to at least one of the orifices arranged for the evacuation of weld vapors or to the vacuum pump.

[0074] According to one aspect of the invention, the welding vapor capture zone and the exhaust channels are arranged to increase the circulation time of the welding vapors inside the anti-contamination hood, so as to allow the cooling and condensation of the welding vapors on the surfaces of the anti-contamination hood, so as to limit the quantity of metal vapors ejected from the anti-contamination hood.

[0075] According to one embodiment of the invention, the welding device is arranged to move opposite the parts to be welded during welding.

[0076] In particular, the welding device is arranged to move laterally opposite the parts to be welded during welding.

[0077] Thus, the movement of the welding zone along the junction between the parts to be welded is achieved by moving the welding device opposite the parts to be welded.

[0078] According to one aspect of the invention, the main axis of the welding unit maintains a constant orientation relative to the welding device, in particular relative to the welding unit, during welding.

[0079] According to one aspect of the invention, the main axis of the welding unit maintains a constant orientation relative to the parts to be welded during welding.

[0080] At each instant of the movement, a so-called "transverse" component of the movement is defined as the component of the movement varying the position of the welding zone on the parts to be welded, while keeping the working distance and the angle α formed between the main axis of the welding unit and the surface of the parts to be welded fixed.

[0081] According to one aspect of the invention, the welding device is arranged to be set in motion during welding, this movement comprising a non-zero transverse component.

[0082] Thus, the anti-contamination hood moves laterally in contact with the at least one part to be welded.

[0083] According to one aspect of the invention, the angle α formed between the main axis of the welding unit and the parts to be welded remains substantially constant during the movement of the welding device.

[0084] According to one aspect of the invention, the angle a remains included during the entire movement of the welding device during welding in an interval [a0 - A, aO + A], with aO a reference angle between the main axis of the welding unit and the parts to be welded, and A representing a maximum deviation from this angle.

[0085] According to one aspect of the invention, A is less than 10°, in particular less than 3°.

[0086] Advantageously, limiting the maximum deviation relative to a reference angle a0 makes it possible to guarantee uniform welding during the welding process, in particular over the entire movement of the welding device.

[0087] According to one aspect of the invention, a0 is equal to 90°.

[0088] Alternatively, the welding device is arranged to be placed inclined relative to the parts to be welded, and the reference angle a0 is between 0° and 90°, in particular between 20° and 70°, in particular between 40° and 50°, in particular equal to 45°.

[0089] According to one aspect of the invention, the welding device is inclined so that the welding zone is placed behind the welding unit in the direction of movement of the welding device.

[0090] According to another embodiment of the invention, the welding unit comprises an orientation element arranged to modify the orientation of the main axis of the welding unit relative to the welding device, in particular relative to the welding unit, during welding.

[0091] According to one aspect of the invention, the orientation element is for example: - in the case of arc welding, a controllable articulation of the welding electrode, - in the case of laser welding, a movable lens or mirror placed in the path of the laser beam and arranged to direct the laser beam, - in the case of electron beam welding, a focusing coil placed in the path of the electron beam, and arranged to direct the electron beam,

[0092] According to one aspect of the invention, the welding device is arranged to remain stationary relative to the parts to be welded during welding.

[0093] Thus, the displacement of the welding zone along the junction between the parts to be welded is achieved by modifying the orientation of the main axis of the welding unit relative to the welding device by the orientation element.

[0094] The invention relates to a welding method carried out by a welding device as described, the welding method comprising in this order the following steps: - a step of placing the welding device in contact with the parts to be welded, - a step of activating the welding unit, starting the welding and generating a weld pool, - a step of moving the welding zone along the junction between the parts to be welded, - a step of stopping the action of the welding unit, completing the welding, - possibly, a cooling step, - a step of removing the welding device, comprising a step of moving the welding device away from the parts to be welded.

[0095] Alternatively, the step of moving the welding device may begin before the welding unit is put into operation and / or end after the welding unit has stopped operating or after the cooling step.

[0096] According to one aspect of the invention, the cooling step is a waiting step allowing the solidification of the solder bath, and the condensation of the solder vapors.

[0097] According to one aspect of the invention, the step of moving the welding zone along the junction between the parts to be welded comprises a step of lateral movement of the welding device in contact with the parts to be welded.

[0098] According to one aspect of the invention, the step of moving the welding zone along the junction between the parts to be welded comprises a step of modifying the orientation of the main axis of the welding unit relative to the welding device.

[0099] Other characteristics, details and advantages of the invention will emerge more clearly on reading the description which follows on the one hand, and several examples of embodiment given for informational and non-limiting purposes with reference to the appended schematic drawings on the other hand, in which:

[0100] [Fig-1] [Fig.l] is a schematic representation of a welding device according to a first embodiment of the invention.

[0101] [Fig.2] [Fig.2] is a schematic representation of a welding device according to the invention placed in contact with parts to be welded of flat, curved and tubular shapes.

[0102] [Fig.3] [Fig.3] is a schematic representation of a welding device according to an embodiment in which the anti-contamination hood is hermetic, and the welding device comprises a vacuum pump.

[0103] [Fig.4] [Fig.4] is a schematic representation of a welding device according to another embodiment in which the anti-contamination cover comprises at least one part made of a porous material.

[0104] [Fig.5] [Fig.5] is a schematic representation of a welding device according to an embodiment of the invention in which the anti-contamination hood comprises evacuation channels and a protective shield.

[0105] [Fig.6] [Fig.6] is a schematic representation of a welding device according to an embodiment of the invention in which the welding device is inclined relative to the parts to be welded.

[0106] [Fig.7] [Fig.7] is a front view and a top view of a welding device according to an embodiment of the invention in which the parts to be welded are tubular in shape, and the anti-contamination hood completely surrounds a tubular section of the parts to be welded.

[0107] [Fig.8] [Fig.8] is a schematic representation of a welding device according to one embodiment of the invention in which the welding unit comprises an orientation element arranged to modify the orientation of the main axis of the welding unit relative to the welding device.

[0108] The features, variants and the different embodiments of the invention may be combined with each other, in various combinations, to the extent that they are not incompatible or mutually exclusive. In particular, variants of the invention may be imagined comprising only a selection of features described below in isolation from the other features described, if this selection of features is sufficient to confer a technical advantage and / or to differentiate the invention from the prior art.

[0109] [Fig.l] shows a welding device 1 according to an embodiment of the invention, placed opposite two parts to be welded 2.

[0110] The welding device 1 is arranged to carry out welding between them of the two parts to be welded 2.

[0111] The welding device 1 is arranged to be used in space, under vacuum conditions, in particular for the assembly of structures in space.

[0112] The welding device comprises a welding unit 3, arranged to carry out a weld along the junction 4 of the two parts to be welded 2, generating a weld pool 5 at a weld zone 10.

[0113] The welding is carried out dynamically, so that the welding zone 10 moves along the junction 4 between the parts to be welded 2 during the welding.

[0114] The welding device also comprises an anti-contamination hood 6 placed movably in contact with the parts to be welded 2 so that the welding unit and the anti-contamination hood encompass the entire weld pool 5.

[0115] [Fig.l] shows half-lines 7 coming from the weld pool 5.

[0116] Any half-line starting from the weld pool 5 intersects either the anti-contamination hood 6 or the weld unit 3.

[0117] Thus, an ejecta 8 which is expelled from the weld bath 5 and which follows a straight line trajectory is stopped by the anti-contamination hood 6, the welding unit 3 or the parts to be welded 2. Thus the ejecta cannot exit in a straight line from the volume defined by the hood, the welding unit and the parts to be welded.

[0118] The welding unit 3 and the anti-contamination hood 6 encompass the entire bath welding 5 without including all the parts to be welded 2.

[0119] The welding device 1 is arranged to move laterally opposite the parts to be welded 2 during welding.

[0120] The movement of the welding device 1 opposite the parts to be welded 2 thus allows the relative movement of the welding zone 10 on the parts to be welded.

[0121] The welding unit 3 is an electron beam gun. The welding unit causes the parts to be welded to melt by emitting an electron beam 9 striking the surface at an external body welding zone.

[0122] A main axis of the welding unit 12 is defined as the main axis of the electron beam 9, and the welding zone 10 as the intersection between the main axis of the welding unit and the surface of the parts to be welded 2.

[0123] According to other embodiments of the invention not shown, the welding unit 3 may for example be a resistance welding device, or an arc welding device, or a laser welding device. The main axis of the welding unit may thus be for example the main axis of a welding electrode, or of a laser beam.

[0124] The welding unit 3 is arranged to perform a weld generating a weld pool 5 at the welding zone 10.

[0125] The main axis 12 of the electron beam is then for example the main axis of the welding electrode, or the main axis of the laser beam.

[0126] In this embodiment, the main axis 12 of the welding unit 3 maintains a constant orientation relative to the welding device 1, in particular relative to the welding unit 3, during welding.

[0127] The main axis 12 of the welding unit 3 also maintains a constant orientation relative to the parts to be welded during welding.

[0128] At each instant of the movement, the working distance 11 is defined as the distance between the welding unit 3 and the parts to be welded 2 along the main axis 12 of the welding unit, i.e. the distance between the welding unit and the welding zone 10 along the main axis 12 of the welding unit.

[0129] The main axis of the welding unit 12 forms an angle α with the parts to be welded, and this angle α remains substantially constant during the movement of the welding device 1.

[0130] The angle a is defined as the angle between the main axis of the welding unit 3 and the plane tangent to the surface of the parts to be welded 2 at the welding zone.

[0131] At each instant of movement of the welding device 1, a so-called “transverse” component 27 of the movement is defined as the component of the movement varying the position of the welding zone 10 on the parts to be welded 2, while keeping fixed the working distance 11 and the angle between the main axis 12 of the welding unit 3 and the surface of the parts to be welded 2.

[0132] The angle a remains included during the entire movement of the welding device during welding in an interval [a0 - A, aO + A], with aO a reference angle between the main axis 12 of the welding unit 3 and the parts to be welded 2, and A representing a maximum deviation from this angle.

[0133] In the embodiment shown, aO is equal to 90°, and A is less than 10°, in particular less than 3°.

[0134] Advantageously, limiting the maximum deviation relative to a reference angle aO makes it possible to guarantee uniform welding during the welding process, in particular over the entire movement of the welding device 1.

[0135] The welding device 1 moves laterally opposite the parts to be welded 2 during welding, i.e. is in movement during welding, this movement comprising a non-zero transverse component 27.

[0136] The anti-contamination hood 6 is kept in contact with the parts to be welded 2 during at least part of the welding, in particular during the entire welding.

[0137] Thus, the anti-contamination hood 6 moves laterally in contact with the parts to be welded 2.

[0138] The anti-contamination cover 6 is formed of several parts secured to each other, these different parts being formed of different materials.

[0139] The anti-contamination hood 6 comprises an anti-contamination skirt 16, and an anti-contamination envelope 17.

[0140] Alternatively, according to an embodiment not shown, the anti-contamination cover 6 is formed from a single piece.

[0141] The anti-contamination cover 6 comprises at least one part made of heat-resistant material 18, for example stainless steel, and at least one part made of flexible material 19, for example a polymer.

[0142] Advantageously, the use of a flexible material makes it possible to keep the anti-contamination cover 6 in contact with a non-smooth surface.

[0143] The anti-contamination envelope 17 is tubular in shape.

[0144] The anti-contamination skirt 16 is formed from a flexible material with a low coefficient friction, for example in polymers.

[0145] According to an embodiment not shown, the anti-contamination envelope 17 may be of any other shape, in particular conical or curved.

[0146] The anti-contamination jacket 17 is fixed on the welding unit, and the anti-contamination skirt 16 is fixed on the anti-contamination jacket to form the anti-contamination hood 6.

[0147] The anti-contamination envelope 17, the welding unit 3 and the anti- contamination 16 are assembled irreversibly.

[0148] Alternatively, the welding unit 3, the anti-contamination envelope 17 and / or the anti-contamination skirt 1 are assembled in a reversible manner, so as to allow the replacement of the anti-contamination skirt 16 and / or the anti-contamination envelope 17 without damaging the parts.

[0149] The anti-contamination hood 6 thus formed is hermetic, that is to say forms with the parts to be welded 2 and the welding unit 3 a hermetically sealed space.

[0150] [Fig.2] shows a welding device 1 according to the invention placed opposite parts to be welded 2 having a flat surface 13, a curved surface 14, and a tubular surface 15.

[0151] [Fig. 3] shows the welding device 1 according to an embodiment of the invention in which the welding device 1 comprises a vacuum pump 20 connected to the hermetically sealed space formed by the anti-contamination hood 6 and the parts to be welded 2, and arranged for the evacuation of metal vapors.

[0152] [Fig.4] shows the welding device according to an alternative embodiment in which the anti-contamination cover 6 comprises at least one part made of a porous material.

[0153] The anti-contamination hood 6 thus comprises a plurality of orifices 21 arranged for the evacuation of welding vapors.

[0154] Advantageously, the use of an anti-contamination hood 6 comprising at least one orifice 21 makes it possible to avoid an accumulation of metal vapors inside the anti-contamination hood.

[0155] In this embodiment, the anti-contamination envelope 17 is made of a porous material, for example a metal foam or a lattice structure.

[0156] In particular, the anti-contamination envelope comprises a plurality of porous layers 22, for example a plurality of perforated plates.

[0157] [Fig. 5] shows a welding device 1 according to an embodiment of the invention in which the anti-contamination cover 6 comprises evacuation channels 23.

[0158] The discharge channels 23 comprise one end placed close to the weld pool 24 generated by the welding unit, and one end connected to an orifice of the anti-contamination cover 25.

[0159] The discharge channels 23 are arranged for the circulation of welding vapors from the welding bath 5 to the outside of the anti-contamination hood 6.

[0160] According to an embodiment not shown, the evacuation channels 6 comprise one end placed close to the solder bath generated by the soldering unit 3 and one end connected to the vacuum pump 20, and are arranged for the circulation of solder vapors from the solder bath to the vacuum pump.

[0161] This figure also shows a protective shield 26 of the anti-contamination cover 6.

[0162] The protective shield 26 is placed inside the anti-contamination hood 6, around the main axis 12 of the welding unit 3, and is arranged to limit the presence of welding ejecta and welding vapors along the main axis of the welding device.

[0163] The protective shield 26 is in particular arranged to minimize, in a plane normal to the main axis of the welding unit, the passage surface 28 that ejecta emitted by the weld pool and moving in a straight line could cross to reach the welding unit 3.

[0164] This passage surface 28 minimized by the protective shield 3 also influences the flow rate of metal vapors which can propagate along the main axis 12 of the welding unit 3 and which can disrupt the welding.

[0165] In the case of laser welding or electron beam welding, the protective shield 26 thus advantageously makes it possible to limit the disturbance of the beam by vapors or ejecta which could alter the quality of the weld.

[0166] The protective shield 26 has a layered structure, and the discharge channels 23 are formed between the layers of the protective shield.

[0167] According to an embodiment not shown, the protective shield 26 and / or the evacuation channels 23 are tubular in shape.

[0168] The protective shield 26 and the evacuation channels 23 are formed as a unit with the anti-contamination casing 17.

[0169] According to an embodiment not shown, the protective shield 26, the evacuation channels 23 and / or the anti-contamination envelope 17 may be separate parts.

[0170] [Fig.6] shows a welding device 1 according to an embodiment in which the welding device is inclined, and the reference angle a0 is equal to 45°.

[0171] The welding device 1 is inclined so that the welding zone 10 is placed behind the welding unit 3 in the direction of movement of the welding device.

[0172] The anti-contamination hood 6 shown in this figure comprises a welding vapor capture zone 9, arranged to allow condensation of the welding vapors on the walls of the anti-contamination hood 6.

[0173] The weld creates a pressure differential, with a high pressure close to the weld pool 5, and a negative gradient away from the weld pool. This pressure differential is the cause of the displacement of the weld vapors from the weld pool 5 to at least orifices 21 arranged for the evacuation of welding vapors.

[0174] The welding vapor capture zone 29 is arranged to increase the circulation time of the welding vapors inside the anti-contamination hood, so as to allow the cooling and condensation of the welding vapors on the surfaces of the anti-contamination hood 6, so as to limit the quantity of metal vapors ejected from the anti-contamination hood.

[0175] In an embodiment where the anti-contamination hood 6 comprises exhaust channels 23, the exhaust channels are also arranged to increase the circulation time of the solder vapors inside the anti-contamination hood.

[0176] The welding vapor capture zone 29 is of domed shape, in particular is a dome 30, and is formed by the anti-contamination envelope.

[0177] In an embodiment not shown, the welding vapor capture zone 29 may be formed by the anti-contamination skirt 16, by the anti-contamination envelope 17, by an evacuation channel 23 or by the protective shield 26.

[0178] According to one aspect of the invention, the welding vapor capture zone 29 is placed vertically above the welding zone 10, i.e. opposite the surface of the parts to be welded 2.

[0179] In the embodiment illustrated in [Fig.6] the protective shield 26 is of planar shape, and forms a pierced disc allowing the passage of the electron beam along the main axis 12 of the welding unit 3.

[0180] [Fig.7] shows a front view and a top view of a welding device 1 according to an embodiment in which the parts to be welded 2 are tubular in shape, and the anti-contamination hood 6 completely surrounds a tubular section 31 of the parts to be welded.

[0181] [Fig. 8] shows a welding device 1 according to an embodiment in which the welding unit 3 comprises an orientation element 32 arranged to modify the orientation of the main axis 12 of the welding unit 3 relative to the welding device 1, in particular relative to the welding unit 3, during welding.

[0182] The orientation element 20 is a focusing coil placed on the path of the electron beam, in particular on the main axis 12 of the welding unit 3 and arranged to direct the electron beam.

[0183] In an embodiment not shown, the orientation element 32 may be a controllable articulation of a welding electrode, or a movable lens or mirror placed in the path of a laser beam.

[0184] The welding device 1 is arranged to remain stationary relative to the parts to be welded 2 during welding. Thus, the movement of the welding zone 10 along the junction 4 between the parts to be welded 2 is achieved by changing the orientation of the main axis 12 of the welding unit 3 relative to the welding device by the orientation element 32.

Claims

Claims

1. Welding device (1) arranged to carry out welding between them of at least two parts to be welded (2), the welding device comprising - a welding unit (3) arranged to carry out welding along the junction (4) of two parts to be welded, generating a weld pool (5) at a welding zone (10), - an anti-contamination hood (6) arranged to be placed, in particular movable, in contact with the parts to be welded (2) so that the welding unit (3) and the anti-contamination hood (6) encompass the entire weld pool (5) and so that any half-line (7) starting from the weld pool intersects either the anti-contamination hood or the welding unit, the welding device (1) being in particular arranged to move the welding zone (10) relative to the parts to be welded during welding.

2. Welding device (1) according to claim 1, arranged to carry out the welding between them of the at least two parts (2) to be welded dynamically, that is to say in such a way that the welding zone (10) moves along the junction (5) between the parts to be welded during the welding.

3. Welding device according to one of the preceding claims, wherein the welding unit (3) is an electron beam gun arranged to cause the fusion of the parts to be welded (2) by the emission of an electron beam striking the surface of the parts to be welded at the welding zone (10).

4. Welding device (1) according to one of the preceding claims, arranged for use in space, under vacuum conditions, in particular arranged for the assembly of structures in space.

5. Welding device (1) according to one of the preceding claims, in which the anti-contamination cover (6) comprises at least one part made of flexible material, for example a polymer.

6. Welding device (1) according to one of the preceding claims, in which the anti-contamination hood (6) comprises: - an anti-contamination skirt (16), - an anti-contamination envelope (17), the welding unit (3), the anti-contamination envelope (17) and / or the anti-contamination skirt (16) being assembled in a reversible manner, so as to allow the replacement of the anti-contamination skirt (16) and / or the anti-contamination envelope (17) without damaging the parts.

7. Welding device (1) according to one of the preceding claims, in which the anti-contamination hood (6) is hermetic, i.e. forms a hermetically sealed space with the parts to be welded (2) and the welding unit (3).

8. Welding device (1) according to claim 7, comprising a vacuum pump (20) connected to the hermetically sealed space formed by the anti-contamination hood (6) and the parts to be welded (2), and arranged for the evacuation of metal vapors

9. Welding device (1) according to one of claims 1 to 6, in which the anti-contamination hood (6) comprises at least one orifice (21) arranged for the evacuation of welding vapors.

10. Welding device (1) according to claim 9, in which the anti-contamination envelope (17) is made of a porous material

11. Welding device (1) according to one of claims 9 to 10, wherein the anti-contamination hood (6) comprises at least one discharge channel (23) arranged for the circulation of welding vapors from the welding bath (5) towards the outside of the anti-contamination hood (6).

12. Welding device (1) according to claim 11, wherein the discharge channels (23) comprise one end (24) placed close to the weld pool (5) generated by the welding unit (3), and one end (25) connected to an orifice (21) of the anti-contamination cover (6).

13. Welding device (1) according to one of the preceding claims, wherein the anti-contamination hood comprises a protective shield (26) arranged inside the anti-contamination hood (6), placed around the main axis (12) of the welding unit (3), and arranged to limit the presence of welding ejecta and welding vapors along the main axis of the welding unit.

14. Welding device (1) according to one of the preceding claims, in which the anti-contamination hood (6) comprises a zone of capture (29) of welding vapors arranged to allow condensation of welding vapors on the walls of the anti-contamination hood (6).

15. Welding device (1) according to one of the preceding claims, arranged to move opposite the parts to be welded (2) during welding.

16. Welding device (1) according to claim 15, wherein the angle a formed between the main axis (12) of the welding unit (3) and the surface of the parts to be welded (2) remains included during the entire movement of the welding device (1) during welding in an interval [a0 - A, aO + A], with aO a reference angle between the main axis (12) of the welding unit (3) and the parts to be welded (2), and A representing a maximum deviation from this angle with A less than 10°, in particular less than 3°.

17. Welding device (1) according to claim 16, wherein the angle aO is equal to 90°.

18. Welding device (1) according to claim 16, arranged to be placed inclined relative to the parts to be welded (2) so that the welding zone (10) is placed behind the welding unit (3) in the direction of movement of the welding device (1), and the reference angle aO is between 0° and 90°, in particular between 20° and 70°, in particular between 40° and 50°, in particular equal to 45°.

19. Welding device (1) according to one of the preceding claims, wherein the welding unit (3) comprises an orientation element (32) arranged to modify the orientation of the main axis (12) of the welding unit (3) relative to the welding device (1), in particular relative to the welding unit (3), during welding.

20. Welding method carried out by a welding device (1) according to one of the preceding claims, the welding method comprising in this order the following steps: - a step of placing the welding device (1) in contact with parts to be welded (2), - a step of actuating the welding unit (3), starting the welding and generating a weld pool (5), - a step of moving the welding zone (10) along the junction (4) between the parts to be welded (2), - a step of stopping the action of the welding unit (3), finishing the weld, - possibly, a cooling step, - a step of removing the welding device (1), comprising a step of moving the welding device away from the parts to be welded (2).

21. Welding method according to claim 20, wherein the step of moving the welding zone (10) along the junction (4) between the parts to be welded (2) comprises a step of lateral movement of the welding device (1) in contact with the parts to be welded.

22. Welding method according to one of claims 20 to 21, in which the step of moving the welding zone along the junction (4) between the parts to be welded (2) comprises a step of modifying the orientation of the main axis (12) of the welding unit (3) relative to the welding device.

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