Observation device for observing a process that generates metallic vapors

Abstract

Observation device for observing a process generating metallic vapors. Observation device (10) for observing a process generating metallic vapors (55) comprising an observation means (11) and a protection device (13) comprising a first shutter (14) and a second shutter (15) movable relative to the observation means (11), the first shutter (14) comprising a first opening (141) intended to be positioned in the field of view (FO) of the observation means (11) for a given position of the first shutter (14), the second shutter (15) comprising a second opening (151) intended to be positioned in the field of view (FO) of the observation means (11) for a given position of the second shutter (15), the protection device (13) comprising a drive means (16) configured to move the first shutter (14) and the second shutter (15) so that the openings (141,151) are positioned periodically and simultaneously in the field of observation (CO). Figure for the abbreviation: figure 2,

Description

Title of the invention: Observation device for observing a process generating metal vapors Technical field of the invention

[0001] The invention relates to an observation device for observing a process generating metal vapors, and more particularly to an observation device for observing a metallurgical process generating such metal vapors. The invention also relates to a manufacturing device equipped with such an observation device. The invention further relates to various methods of using such an observation device and / or such a manufacturing device equipped with an observation device. State of the prior art

[0002] It is known to use observation means to monitor manufacturing processes in hostile or difficult-to-access environments in which observation with the naked eye is not possible. Thus, for example, it is known to use cameras to monitor in real time processes generating metal vapors, such as vacuum welding processes. However, the release of metal vapors and / or projections can dirty or even damage the camera lens.

[0003] A known solution to this problem is to use an "on-off" shutter configured to completely obstruct the optical sighting channel of the observation device to protect the objective of the observation means from metal vapors. The optical sighting channel is cleared for a brief time before being masked again so as to allow rapid observation of a manufacturing process.

[0004] However, this solution has drawbacks. It does not effectively protect the camera lens and / or is not suitable for metallurgical processes requiring a longer manufacturing time. Indeed, the release of metal vapors and projections are more abundant in these configurations.

[0005] Another known solution is a rotating slot which allows vision through the slot and blocks the metallization the rest of the time.

[0006] However, this solution has drawbacks and limitations. The protection is not complete and the metallization that passes through quickly ends up polluting the optical elements such as mirrors, lenses or cameras. The compromise between vision and protection means that the protection factor is limited.

[0007] Furthermore, in the case where the metallurgical process designates a vacuum welding process using a welding apparatus equipped with an electron gun, it is particularly important to be able to correct a potential beam trajectory defect. of electrons. It therefore becomes necessary to monitor the evolution of the weld bead in real time, but the "all or nothing" shutter does not provide a satisfactory solution to this problem. Presentation of the invention

[0008] The aim of the invention is to provide an observation device for observing a process generating metal vapors, and more particularly an observation device for observing a metallurgical process generating such metal vapors, remedying the above drawbacks and improving the known devices of the prior art.

[0009] In particular, a first object of the invention is an observation device for observing a process generating metal vapors which effectively protects a camera and / or optical elements, such as a mirror and / or one or more lenses from projections of metal particles while allowing a relatively long metallurgical process to be observed. Summary of the invention

[0010] For this purpose, the invention relates to an observation device for observing a process generating metal vapors, the observation device comprising an optical observation means and a protection device positioned in an observation field of the observation means to protect the observation means, characterized in that the protection device comprises a first shutter movable relative to the observation means and a second shutter movable relative to the observation means, the first shutter comprising at least one first opening intended to be positioned in the observation field of the observation means for a given position of the first shutter, the second shutter comprising at least one second opening intended to be positioned in the observation field of the observation means for a given position of the second shutter,the protection device further comprising a drive means configured to move the first shutter and the second shutter such that the first opening and the second opening are positioned periodically and simultaneously in the field of observation of the observation means.

[0011] According to one embodiment, the first shutter is movable in rotation around a first axis of rotation and the second shutter is movable in rotation around a second axis of rotation.

[0012] In this same embodiment, the drive means is configured to rotate the first shutter at a first speed and to rotate the second shutter at a second speed, the first speed being a multiple of the second speed or the second speed being a multiple of the first speed.

[0013] Furthermore, the first axis of rotation is coincident with the second axis of rotation.

[0014] In this same embodiment, the field of observation of the observation means is offset relative to the axis of rotation of the first and second shutters.

[0015] According to one embodiment, the first shutter and the second shutter are made of non-reflective materials.

[0016] According to one embodiment, the first shutter comprises a first wall in which said at least one first opening is formed, the first wall comprising a disc shape or a cylindrical shape or a conical shape and the second shutter comprises a second wall in which said at least one second opening is formed, the second wall comprising a disc shape or a cylindrical shape or a conical shape.

[0017] According to one embodiment, the first wall of the first shutter and the second wall of the second shutter each have a cylindrical shape and the at least one first opening and the at least one second opening are offset relative to the centers of the first and second cylindrical walls.

[0018] According to one embodiment, the observation device comprises an adjustment means configured to align the first opening of the first shutter with the second opening of the second shutter in the field of observation of the observation means.

[0019] According to one embodiment, the first shutter comprises at least one balancing means, in particular at least one balancing opening positioned outside the field of observation of the observation means regardless of the position of the first shutter.

[0020] Furthermore, the second shutter comprises at least one balancing means, in particular at least one balancing opening positioned outside the field of observation of the observation means regardless of the position of the second shutter.

[0021] According to one embodiment, the protection device comprises a transparent or translucent protection panel arranged between the optical observation means and the assembly formed by the first and second shutters, the protection panel being positioned in the field of observation of the optical observation means to protect the optical observation means.

[0022] According to a variant of this embodiment, the protective panel is movable in rotation around an axis of rotation.

[0023] The invention also relates to a manufacturing device comprising a chamber configured to house processes generating metal vapors, such as metallurgical processes, the manufacturing device also comprising an observation device as described previously and comprising in particular a vacuum pump designed to generate a vacuum inside the chamber.

[0024] According to one embodiment of the manufacturing device, the latter further comprises an electron gun configured to produce an electron beam inside the chamber.

[0025] The invention also relates to a method of using the observation device or the manufacturing device, characterized in that the drive means moves the first movable shutter and the second movable shutter so that the first aperture and the second aperture are positioned periodically and simultaneously in the field of observation of the optical observation means and in that the optical observation means of the observation device takes a picture when the first aperture and the second aperture are positioned simultaneously in the field of observation of the observation means.

[0026] According to one embodiment, the drive means is controlled so as to slow down the movements of the first shutter and the second shutter until they are immobilized and the adjustment means is used to align the first opening of the first shutter with the second opening of the second shutter in the field of observation of the optical observation means when the shutters are immobilized. Presentation of figures

[0027] These objects, characteristics and advantages of the present invention will be explained in detail in the following description of several particular embodiments given without limitation in relation to the attached figures among which:

[0028] [Fig.l] is a schematic view of a manufacturing device equipped with an observation device.

[0029] [Fig.2] is a schematic view of the observation device according to a first embodiment of the invention.

[0030] [Fig.3A] is a schematic view of a detail of a protection device according to a first embodiment of the invention in a first position.

[0031] [Fig.3B] is a view similar to [Fig.3A] with the protective device in a second position.

[0032] [Fig.3C] is a view similar to Figures 3A and 3B with the protective device in a third position.

[0033] [Fig.4A] is a schematic view of the protection device according to the first embodiment of the invention seen from above in the first position.

[0034] [Fig.4B] is a view similar to [Fig.4A] with the protective device in the second position.

[0035] [Fig.4C] is a view similar to Figures 4A and 4B with the device of protection in the third position.

[0036] [Fig.4D] is a view similar to Figures 4A, 4B and 4C with the protective device in any position.

[0037] [Fig.5A] is a schematic view of the first shutter of the protection device according to a second embodiment.

[0038] [Fig.5B] is a schematic view of the second shutter of the protection device according to the second embodiment.

[0039] [Fig.6] is a schematic view of the first and second shutters according to a third embodiment.

[0040] [Fig.7A] is a schematic and perspective view of the protection device according to a second embodiment of the invention in the third position.

[0041] [Fig.7B] is a view similar to [Fig.7A] with the shutters in a different position.

[0042] [Fig.8A] is a schematic view of the protection device according to the second mode seen from above with the shutters in the first position.

[0043] [Fig.8B] is a view similar to [Fig.8A] with the shutters in the second position.

[0044] [Fig.8C] is a view similar to Figures 8A and 8B with the shutters in the third position.

[0045] [Fig.9A] is a schematic view of the second shutter according to the second embodiment seen from above in a fourth position.

[0046] [Fig.9B] is a view similar to [Fig.9A] with the second shutter in a fifth position.

[0047] [Fig.9C] is a schematic view of the protection device according to the second embodiment seen from above with the shutters in their fourth position.

[0048] [Fig.9D] is a view similar to [Fig.9C] with the shutters in their fifth position.

[0049] [Fig. 10] is a schematic view of a protection panel of the protection device.

[0050] [Fig. 1 IA] is a schematic view of a balancing means for the first shutter.

[0051] [Fig. 1 IB] is a schematic view of a balancing means for the second shutter.

[0052] [Fig.l2A] is a schematic view of an adjustment means for the first shutter.

[0053] [Fig. 12B] is a schematic view of an adjustment means for the second shutter.

[0054] [Fig. 13] illustrates three different positions of the shutters of Figures 12A and 12B during a process of using the observation device. Detailed description

[0055] [Fig.l] schematically illustrates manufacturing device 1 which comprises a chamber 2 configured to house processes generating metal vapors 55, and a vacuum pump 3 which is intended to generate a depression inside the chamber 2.

[0056] The manufacturing device 1 is also equipped with an observation device 10 comprising an optical observation means 11 (visible in [Fig. 2]), such as a camera or a video camera. In [Fig. 2], the observation device 10 also comprises a mirror 12 placed in an observation field CO of the observation device 10 and positioned so as to reflect the interior of the chamber 2 of the manufacturing device 1 towards the observation means 11. Thanks to a specific inclination angle of the mirror 12, the latter makes it possible to convey the image of the interior of the chamber 2 of the manufacturing device 1 towards the optical observation means 11 in order to observe in real time the events inside said chamber 2.

[0057] The manufacturing device 1 illustrated in [Fig.l] may further comprise an electron gun 20 configured to produce an electron beam FE inside the chamber 2. The electron gun 20 may in particular comprise a cathode 21, an anode 22, and possibly a wehnelt 23 interposed between the cathode 21 and the anode 22. The cathode 21 is capable of emitting electrons. It may for example be in the form of a filament or a solid or hollow emitting part. For example, the electrons may be extracted from a hot thermo-emissive or gaseous cathode. The anode 22 is capable of attracting electrons by means of an electrical voltage applied between the cathode 21 and the anode 22. The electrical voltage between the anode 22 and the cathode 21 can reach, for example, a value of the order of several tens of kilovolts. The wehnelt 23 makes it possible to regulate the quantity of electrons emitted by the cathode 21.In particular, the voltage difference between wehnelt 23 and cathode 21 makes it possible either to block the electrons and prevent the emission of the electron beam FE, or to allow part or all of the electron flow emitted by the cathode 21 to pass. The anode 22, the wehnelt 23 and the cathode 21 can be assembled so as to be mechanically aligned along a first axis Z illustrated in [Fig.l]. Thus, it is possible to obtain at the output of the electron gun 20, an electron beam FE with an optimal symmetry of revolution around the axis Z.

[0058] As appears in the schematic representation of the manufacturing device 1 in [Fig.l], the manufacturing device 1 may further comprise a focusing means 30 and a deflection means 40 which may be grouped in a housing 4 (or in other words a casing).

[0059] Such an electron gun 20 may in particular equip an electron beam welding apparatus. The manufacturing device 1 then comprises an electron beam welding apparatus, capable of projecting an electron beam FE onto one or more parts 50A, 50B to be welded in order to melt them locally. The observation device 10 makes it possible in this case to follow the welding process in real time.

[0060] The electron beam FE is a flow of electrons which is projected onto the part(s) 50A, 50B to be welded. The energy dissipated by the impact of the electrons on the parts 50A, 50B to be welded causes heating and therefore local melting of the material. The power of the welding apparatus is particularly suitable for welding metal parts, for example parts made of niobium, copper, aluminum or any other type of metal. The two parts 50A, 50B are welded to each other using a weld bead formed at their interface. The interface designates the joint or in other words the junction line separating the two parts 50A, 50B.

[0061] Electron beam welding requires that the electron beam FE propagates in a vacuum. The chamber 2 can therefore close hermetically around the parts 50A, 50B to be welded and the welding apparatus and the vacuum pump 3 can then create a vacuum in the chamber. An order of magnitude of the vacuum level reached in the chamber can be for example between 10-2 mBar and 10-6 mBar.

[0062] Alternatively, the observation device 10 could also equip any other type of manufacturing device capable of causing the formation of metal vapors, such as for example an additive manufacturing device. The observation device 10 in this case makes it possible to monitor the manufacturing of a part inside the chamber 2 in real time.

[0063] During the manufacturing process, particularly in the case of long welding processes on large parts and / or parts having a complex geometry, there may be abundant releases of metal vapors 55. These metal vapors 55 can potentially damage the observation device 10. They can in particular dirty the mirror 12 and / or the objective of the observation means 11, which would make real-time monitoring difficult, or even impossible, and which would significantly degrade the quality of the images, thus making them unusable.

[0064] In order to protect the observation device 10 and these components, the observation device 10 comprises a protection device 13 positioned in an observation field CO of the observation means 11, as illustrated for example in [Fig.2],

[0065] The protection device 13 more particularly comprises a first shutter 14 movable relative to the observation means 11 and a second shutter 15 movable relative to the observation means 11. The first shutter 14 comprises at least a first opening 141 intended to be positioned in the observation field CO of the observation means 11 for a given position of the first shutter 14. Similarly, the second shutter 15 comprises at least one second opening 151 intended to be positioned in the observation field CO of the observation means 11 for a given position of the second shutter 15.

[0066] The apertures 141, 151 may be smaller in size than the extent of the CO observation field.

[0067] In order to cover the entire observation field CO with openings 141, 151 having sizes smaller than the extent of the observation field CO, the protection device 13 further comprises a drive means 16 configured to move the first shutter 14 and the second shutter 15 so that the first opening 141 and the second opening 151 are positioned periodically and simultaneously in the observation field CO of the observation means 11.

[0068] In order to limit the propagation of the light rays generated during welding, the shutters 14 and 15 are preferably made of non-reflective materials. The absence of reflection makes it possible to obtain better quality images with the observation means 11. The shutters 14, 15 may, for example, be anodized metal parts, black in color.

[0069] Such a protection device 13 makes it possible to monitor the metallurgical process in real time while effectively protecting the observation device 10 and its components from harmful metal vapors 55 released inside the chamber 2 placed under vacuum.

[0070] Having two shutters 14, 15 makes it possible to considerably increase the protection rate of the observation means 11, while maintaining a limited size of the protection device 13. The protection device 13 also makes it possible to space out maintenance interventions on the observation device 10.

[0071] Several different configurations can be envisaged for the assembly formed by the first shutter 14 and the second shutter 15. These configurations differ from each other by the shape of each of the shutters 14, 15 and by the arrangement of the first shutter 14 relative to the second shutter 15 within the protection device 13 of the observation means 11.

[0072] The first shutter 14 and the second shutter 15 may have similar shapes or different shapes from each other. Depending on the configurations chosen, the first shutter 14 and the second shutter 15 may have similar sizes or different sizes.

[0073] Generally, the first shutter 14 may comprise a first wall 142 in which at least one first opening 141 is formed. This first wall 142 has, for example, a disc shape (as in FIGS. 3A to 3C and 4A to 4D) or a cylindrical shape (as in Figures 5A and 5B and 7A and 7B) or a conical shape (as in [Fig.6]). Similarly, the second shutter 15 may comprise a second wall 152 in which said second opening 151 is formed. This second wall 152 has for example a disc shape or a cylindrical shape or a conical shape.

[0074] Thus, according to a first embodiment of the first shutter 14 and the second shutter 15, the first wall 142 in which the first opening 141 is formed and the second wall 152 in which the second opening 151 is formed both comprise, for example, a disc shape. Such an embodiment is notably illustrated in FIGS. 2, 3A to 3C and 4A to 4D.

[0075] In this first embodiment, the first shutter 14 is rotatable about a first axis of rotation A1, and the second shutter 15 is rotatable about a second axis of rotation A2. The shutters 14, 15 can rotate in the same direction or in opposite directions. Furthermore, it is possible for the first axis of rotation A1 to coincide with the second axis of rotation A2. Arranging the first shutter 14 and the second shutter 15 coaxially so that they are rotatable about the same axis of rotation A1, A2 makes it possible to obtain a relatively compact observation device 10. Preferably, a central axis of the observation field CO is substantially parallel to the axes of rotation A1 and A2.

[0076] According to a second embodiment of the first shutter 14 and the second shutter 15, the first wall 142 and the second wall 152 both comprise, for example, a cylindrical shape. In this particular embodiment, the first shutter 14 comprises two first openings 141 while the second shutter 15 comprises two second openings 151. Such an embodiment is notably illustrated in FIGS. 5A, 5B, 7A, 7B, 8A, 8B, 8C, 9A, 9B, 9C and 9D.

[0077] In a similar manner to the first embodiment described above, the two shutters 14, 15 in this second embodiment are rotatable about their respective axis of rotation A1, A2. Similarly, these axes of rotation A1, A2 may be the same. Similarly, arranging the first shutter 14 and the second shutter 15 coaxially so that they are rotatable about the same axis of rotation makes it possible to obtain a relatively compact observation device 10.

[0078] In the case of the embodiment illustrated in particular in FIGS. 7A, 7B, 8A, 8B, 8C, the second cylindrical wall 152 of the second shutter 15 has an outside diameter D2 smaller than the inside diameter DI of the first cylindrical wall 142 of the first shutter 14. In other words, the second shutter 15 can be housed in the cavity created by the first cylindrical wall 142 of the first shutter 14 so that the first cylindrical wall 142 of the first shutter 14 at least partially surrounds the second cylindrical wall 152 of the second shutter 15.

[0079] According to a third embodiment of the first shutter 14 and the second shutter 15, the first wall 142 in which the first opening 141 is formed comprises a disc shape while the second wall 152 in which the second opening 151 is formed comprises a conical shape. More particularly, the second wall 152 in which the second opening 151 of the second shutter 15 is formed resembles a slice of a cone. In this third embodiment, each shutter 14, 15 is rotatable about its own axis of rotation A1, A2. Furthermore, the axis of rotation A1 of the first shutter 14 and the axis of rotation A2 of the second shutter 15 are inclined relative to each other, as illustrated in [Fig.6].

[0080] Other shapes for the first shutter 14 and / or the second and other configurations for the assembly formed by the first shutter 14 with the second shutter 15 are conceivable. More particularly, a configuration can be imagined in which the wall 142, 152 of one of the two shutters 14 or 15 comprises a disc shape while the wall of the other shutter 14 or 15 comprises a cylindrical shape.

[0081] In a manner common to all embodiments, the openings 141, 151 of the shutters 14, 15 are intended to be positioned in the observation field CO of the observation means 11 for given positions of the two shutters 14, 15 using the drive means 16 configured to move the shutters 14, 15.

[0082] In the embodiments mentioned above, the drive means 16 is configured to rotate the first shutter 14 around the first axis of rotation A1 and to rotate the second shutter 15 around a second axis of rotation A2.

[0083] More specifically, the drive means 16 is configured to rotate the first shutter 14 at a first speed and to rotate the second shutter 15 at a second speed, the first speed being a multiple of the second speed or the second speed being a multiple of the first speed. The first speed may be strictly greater or strictly less than the second speed.

[0084] Thanks to such a drive means 16, the first opening 141 of the first shutter 14 and the second opening 151 of the second shutter 15 are then positioned periodically and simultaneously in the observation field CO of the observation means 11 to allow the observation means 11 to take pictures. Apart from the times in which the two openings 141, 151 are positioned in the observation field CO of the observation means 11, at least one of the shutters 14 or 15 at least partially obstructs the observation field CO so as to protect the observation means 11, thus preventing the metal vapors 55. This also makes it possible to avoid glare due to the molten pool in the case where the metallurgical process observed by the observation device 11 is a vacuum welding process.

[0085] In order to regularly obtain a superposition of the first opening 141 of the first shutter 14 with the second opening 151 of the second shutter 15 in the observation field CO of the observation means 11, it is preferable that the first speed of the first shutter 14 is an integer multiple of the second speed or that the second speed is an integer multiple of the first speed.

[0086] The drive means 16 can thus comprise a reducer 161 coupled to a motor 162 so as to reduce the speed of an output shaft driven in rotation by the motor 162.

[0087] Such a reducer 161 may be in the form of a belt arrangement or in the form of a gear comprising toothed wheels such as pinions and crowns.

[0088] According to a preferred embodiment of the drive means 16, the reducer 161 may be in the form of an epicyclic gear train, as illustrated in FIGS. 7A and 7B.

[0089] In these figures, the epicyclic gear train which forms the reduction gear 161 more particularly comprises a crown sun gear 171, a planet carrier 172, satellites 173 and a pinion sun gear 174. One of the two shutters can then be integral with the planet carrier 172 while the other shutter can be integral with the pinion sun gear 174.

[0090] According to a variant of the embodiment described previously, the observation device 10 comprises a means for modifying the reduction ratio of the reducer 161, the modification means being configured to modify the speed ratio between the first 14 and the second 15 shutter.

[0091] Such a means for modifying the reduction ratio of the reducer 161 makes it possible to modify the speed ratio between the first 14 and the second 15 shutters so as to adjust the shooting rate. Such a means for modifying the reduction ratio of the reducer 161 also makes it possible to influence the quality of the protection and to regulate at least partially the rate of light which arrives at the objective of the observation means 11.

[0092] Thus, in the case where the reducer 161 is in the form of a belt arrangement or in the form of a gear comprising elements such as toothed wheels, it may be possible to move some of said elements, or even to replace them to vary their diameter and / or their number of teeth and / or the position of their rotation axis in order to modify the speed ratio between the first and second shutters 14, 15.

[0093] In the particular case where the reducer 161 is in the form of an epicyclic gear train, it may be envisaged to replace the entire epicyclic gear train with another epicyclic gear train having a different reduction ratio.

[0094] In order to make the observation device 10 more compact, and according to a particular embodiment of the observation device 10, the observation field CO of the observation means 11 can be offset relative to the axis of rotation A1, A2 of the first and second shutters 14, 15. In other words, a central axis of the observation field CO is not intersecting with the axis of rotation A1, A2.

[0095] This is particularly the case for the first embodiment in which the first wall 142 and the second wall 152 both comprise a disc shape. This first embodiment is particularly illustrated in FIGS. 3A to 3C and in FIGS. 4A to 4D. In this first embodiment, the observation field CO of the observation means 11 is offset relative to the axis of rotation A1, A2 of the first and second shutters 14, 15 in the sense that a central axis of said observation field CO is not intersecting with the axis of rotation A1, A2 of the first and second shutters 14, 15. In this first embodiment, the observation field CO of the observation means 11 is offset towards the edge of the first wall 142 of the first shutter 14 and towards the edge of the second wall 152 of the second shutter 15, as illustrated in FIGS. 3A to 3C.

[0096] A similar misalignment of the observation field CO of the observation means 11 relative to the axis of rotation A1, A2 of the first and second shutters 14, 15 can be observed in the case of the second embodiment in which the first wall 142 and the second wall 152 both comprise a cylindrical shape. This is particularly illustrated in FIGS. 7A and 7B as well as in [Fig. 8A] to 8C. More particularly, the viewing channel of the observation field passing through the two openings 141 and the two openings 151 is misaligned relative to the center of the first and second walls 142 and 152 of cylindrical shape. This is more particularly visible in FIGS. 8C and 9A to 9D.

[0097] This particular arrangement of the openings 141, 151 in the cylindrical walls 142, 152 of the shutters 14, 15 has the effect of only allowing the light rays to pass through said openings 141, 151 so as to generate an image once per complete revolution of the shutter 14, 15, and this only when the openings 141, 151 are aligned with each other in the observation field CO of the observation means 11. This particular alignment is notably shown in [Fig.8C].

[0098] If only one of the two shutters 14 or 15 is positioned such that its or openings 141 or 151 are aligned in the field of observation CO of the observation means 11, the light rays are blocked by the other shutter. These configurations are illustrated in particular in Figures 8A and 8B. More precisely, in [Fig.8B], the second cylindrical wall 152 of the second shutter 15 forms an obstacle in the field of observation CO of the observation means 11. Similarly, the first cylindrical wall 142 of the first shutter 14 forms an obstacle in the field of observation CO of the observation means 11 in [Fig.8A].

[0099] This misalignment makes it possible to limit the exposure of the observation means 11 to the intense light of the molten bath and to further block the harmful metal vapors 55, which increases the protection factor of the protection device 13.

[0100] In the particular case of the embodiment in which the first wall 142 and the second wall 152 both comprise a cylindrical shape, the observation field CO of the observation means 11 is centered on a direction perpendicular to the axis of rotation A1, A2 of the first and second shutters 14, 15. This is more particularly visible in FIGS. 7A, 7B, 8A to 8C and 9A to 9D.

[0101] Such an arrangement of the observation field CO of the observation means 11 relative to the first shutter 14 and the second shutter 15 can contribute to a compact design of the protection device 13 within the observation device 10.

[0102] In a preferred embodiment of the protection device 13 of the observation device 10, the respective openings 141, 151 of the first and second shutters 14, 15 may have different sizes.

[0103] Thus, in the case of the first embodiment of the first shutter 14 and the second shutter 15, for which the first wall 142 in which the first opening 141 is formed and the second wall 152 in which the second opening 151 is formed both comprise a disc shape, the first opening 141 in the first wall 142 of the first shutter 14 may be larger in dimension than the second opening 151 in the second wall 152 of the second shutter 15. This is notably illustrated in FIGS. 4A to 4D.

[0104] The at least one first opening 141 arranged in the first wall 142 of the first shutter 14 has, for example, larger dimensions than the at least one second opening 151 arranged in the second wall 152 of the second shutter 15. The small second opening 151 arranged in the second wall 152 of the second shutter 15 makes it possible to limit the exposure of the observation means 11 to the intense light of the molten pool and to further block the harmful metal vapors 55, which increases the protection factor of the protection device 13. The large first opening 141 arranged in the first wall 142 of the first shutter 14 makes it possible to transfer the light which passes through the small second opening 151 arranged in the second wall 152 of the second shutter 15 towards the observation means 11 while intercepting a large part of the metal vapors 55 having crossed the wall of the second shutter.

[0105] Having different sizes for the respective openings 141, 151 of the first shutter 14 and the second shutter 15 also makes it possible to differentiate the first shutter 14 from the second shutter 15 during a maintenance operation for example, in particular in the case where the first shutter 14 and the second shutter 15 have similar, or even identical, sizes. Having different sizes for the openings 141, 151 also makes it possible to take into account the opening angle of the field of observation when the two openings are not coplanar and to take into account the different speed ratios.

[0106] In the case of the second embodiment of the first shutter 14 and the second shutter 15, for which the first wall 142 in which the first openings 141 are formed and the second wall 152 in which the second openings 151 are formed both comprise a cylindrical shape, these openings 141, 151 may have different sizes from each other, as illustrated in more detail in FIGS. 9A to 9D.

[0107] In this second embodiment, the shapes of the edges 143a, 143b, 144a and 144b and 153a, 153b, 154a and 154b as well as the sizes of said first and second openings 141, 151 can be dimensioned according to the extent of the observation field CO of the observation means 11 to obtain an optimal compromise between the visibility through said openings 141, 151 and the protection provided by the walls 142, 152 of the shutters 14 and 15 against the metal vapors 55.

[0108] In the context of the explanations given in the remainder of this description, it is assumed that the first and second shutters 14, 15 both rotate clockwise. Furthermore, the extent of the observation field CO is in particular delimited by an upstream limit L1 and a downstream limit L2, as illustrated in FIGS. 9A to 9D.

[0109] In all of Figures 9A, 9B, 9C and 9D, the upstream limit L1 and the downstream limit L2 are each represented by a dotted vertical line. In these figures, the upstream limit L1 and the downstream limit L2 of the extent of the observation field CO are parallel to each other.

[0110] Thus, for an observation field CO having a given extent, the shape of the edges 153a, 153b, 154a and 154b and the sizes of the second openings 151 arranged in the second cylindrical wall 152 of the second shutter 15 can be defined on the one hand by aligning the upstream edges 153a and 154a on the upstream limit L1 and by aligning on the other hand the downstream edges 153b and 154b on the downstream limit L2 of the extent of the observation field CO. This is more particularly illustrated in the Figures 9A and 9B.

[0111] In [Fig.9A], the second shutter 15 is positioned such that the upstream edges 153a and 154a are both aligned with the upstream limit L1 of the observation field CO. This simultaneous alignment of the upstream edges 153a and 154a with the upstream limit L1 determines the respective shapes for each of said upstream edges 153a, 154a as well as their locations within the second wall 152 of the second shutter 15.

[0112] In [Fig.9B], the second shutter 15 is positioned such that the downstream edges 153b and 154b are both aligned with the downstream boundary L2 of the observation field CO. This simultaneous alignment of the downstream edges 153b, 154b with the downstream boundary L2 determines the respective shapes for each of said downstream edges 153b, 154b as well as their locations within the second wall 152 of the second shutter 15, thus delimiting the size of the second openings 151.

[0113] In Figures 9A and 9B, the upstream edges 153a and 154a and the downstream edges 153b and 154b have different shapes; this is due to the fact that the second wall 152 of the second shutter 15 has a cylindrical shape and that the observation field CO of the observation means 11 is offset relative to the axis of rotation A2 of the second shutter 15.

[0114] Similar reasoning can be applied to define the sizes of the first openings 141 arranged in the first cylindrical wall 142 of the first shutter 14, with the difference that defining the locations and the respective shapes of the upstream edges 143a, 144a and the downstream edges 143b, 144b depends not only on the extent of the observation field CO, but also on the geometry of the second openings 151 arranged in the second cylindrical wall 152 of the second shutter 15.

[0115] Indeed, it is preferable to dimension the size of the first openings 141 and the shape of their upstream edges 143a, 144a and their downstream edges 143b, 144b such that when the upstream edges 153a and 154a of the second openings 151 of the second shutters 15 are aligned with the upstream limit L1 of the observation field CO, the downstream edges 143b, 144b of the first openings 141 of the first shutter 14 are also aligned with this same upstream limit L1 of the observation field CO. This is more particularly illustrated in [Fig.9C].

[0116] Similarly, it is preferable to dimension the size of the first openings 141 and the shape of their downstream edges 143b, 144b such that when the downstream edges 153b and 154b of the second openings 151 of the second shutters 15 are aligned with the downstream limit L2 of the observation field CO, the upstream edge 143a and the downstream edge 144b are also aligned with this same downstream limit L2 of the observation field CO. This is more particularly illustrated in [Fig.9D].

[0117] It will be noted that defined in this way, the second opening 151 delimited by the upstream edge 153a and the downstream edge 153b is the smallest of the set of openings 141, 151 while the second opening 151 delimited by the upstream edge 154a and the downstream edge 154b is the largest of the set of openings 141, 151.

[0118] Such a geometry of the first and second openings 141, 151 arranged respectively in the first cylindrical wall 142 of the first shutter 14 and in the second cylindrical wall 152 of the second shutter 15 makes it possible to obtain an optimal compromise between the visibility through said openings 141, 151 and the protection provided by the walls 142, 152 of the shutters 14 and 15 against the metal vapors 55 when said shutters 14, 15 rotate in the same direction around a common axis of rotation A1, A2.

[0119] In the set of embodiments of the shutters 14, 15 described here, a space 18 may separate the first shutter 14 from the second shutter 15, as illustrated in FIGS. 3A to 3C and 8A to 8C for example. Such a space 18 makes it possible to accumulate the metal vapors 55 having escaped from the first shutter 1, they are then for the most part intercepted by the second shutter 15. Furthermore, such a space 18 allows the shutters 14, 15 to continue their movements despite the potential deposits of particles induced by the accumulation of the metal vapors 55 between the two shutters 14, 15. This space 18 may be of the order of a few millimeters.

[0120] According to a particular embodiment, the first shutter 14 may comprise at least one balancing means, in particular at least one balancing opening 251 positioned outside the observation field CO of the observation means 11, whatever the position of the first shutter 14.

[0121] In [Fig. 1 IA] an embodiment of a first shutter 14 with a disc-shaped wall 142 is illustrated, this shutter 14 comprises a first opening 141 located at the edge of its periphery as well as a balancing means 25 which is in the form of a balancing opening 251 in the shape of an arc of a circle. This balancing opening 251 in the shape of an arc of a circle is arranged opposite the first opening 141, on the other side of the axis of rotation A1.

[0122] In addition or as a variant, the second shutter 15 may comprise at least one similar balancing means 25, in particular at least one balancing opening 252 positioned outside the field of observation CO of the observation means 11, regardless of the position of the second shutter 15. Thus, [Fig. 1 IB] illustrates an embodiment of a second shutter 15 with a second disc-shaped wall 152, this shutter 15 comprises a first opening 141 located at the edge of its periphery as well as a balancing means 25 which is in the form of a balancing opening 252 in the shape of an arc of a circle. This balancing opening 252 in the shape of an arc of a circle is arranged opposite the second opening 142, on the other side of the rotation axis A2.

[0123] Such a balancing means 25 makes it possible to prevent the occurrence of vibrations which can cause deformation of the shutter 14, 15 provided with said balancing means 25. Indeed, the movable shutters 14, 15 of the protection device 13 can be subjected to rapid movements, in particular rotations at high speeds. Although the axis of rotation A1, A2 is located substantially at the center of the shutters 14, 15 when these have a shape similar to that of a solid of revolution, the presence of the at least one opening 141, 151 in the wall 142, 152 of a shutter 14, 15 implies an unequal distribution of the masses within said shutter 14, 15, such as an unbalance.Thus, when such a shutter 14, 15 is rotated about an axis of rotation A1, A2 with high speeds, the imbalance due to the unbalance can potentially generate deformations of the walls 142, 152 of the shutter 14, 15, or vibrations thereof, which can shorten their service life. Thus, the presence of a balancing means 25 can make it possible to rebalance the masses within the shutter 14, 15 in order to limit the occurrence of these deformations and / or these vibrations.

[0124] The balancing means 25 may be in other forms. Thus, the shape of an opening 251, 252 may be different from that of an arc of a circle. Furthermore, the balancing means 25 may be in the form of a multitude of openings.

[0125] According to a variant, the balancing means 25 of the first and / or second shutters 14, 15 may involve removing material at specific locations of the walls 142, 152 of the first and / or second shutters 14, 15 so as to reduce the risk of vibrations occurring when the shutters 14, 15 are moved by the drive means 16. Thus, the balancing means 25 may be similar to a hollow or a multitude of hollows distributed within the wall 142, 152 of the shutter 14, 15 in question.

[0126] According to a particular embodiment of the observation device 10, the latter may comprise an adjustment means 28 configured to align the first opening 141 of the first shutter 14 with the second opening 151 of the second shutter 15 in the observation field CO of the observation means 11 when the shutters are kept stationary. Such an adjustment means 28 makes it possible to manually or electronically arrange the positions of the two shutters 14, 15 and those of their respective openings 141, 151 in the observation field CO of the observation means 11 so as to allow observation of the contents of the chamber 2 with the shutters 14, 15 stopped. This allows comfortable observation to be carried out when no metal evaporation occurs.

[0127] According to a particular embodiment of the adjustment means 28 illustrated in FIGS. 12A, 12B and 13, this is in the form of a multitude of openings alignment openings 281 arranged in an arc of a circle in the first shutter 14, and an arc-shaped opening 281 in the second shutter 15. The alignment openings 281 are arranged in an arc of a circle in the first shutter 14 so that all of said openings 281 are in alignment with the arc-shaped opening 282 of the second shutter 15 when the first and second openings 141, 151 of the two shutters 14, 15 are positioned in the field of observation CO of the observation means 11. The spacing between the alignment openings 281 in the first shutter 14 is correlated with the size of the arc-shaped opening 282 in the second shutter 15.

[0128] Moving the shutters 14 and 15 until the alignment openings 281 of the first shutter 14 are in alignment with the arcuate opening 282 of the second shutter 15 ensures alignment of the first and second openings 141, 151 of the two shutters 14, 15 in the field of observation CO of the observation means 11, thus making it possible to observe the contents of the chamber with the shutters 14, 15 stationary.

[0129] According to a particular embodiment of the observation device 10, the protection device 13 further comprises a transparent or translucent protection panel 26 arranged between the optical observation means 11 and the assembly formed by the first and second shutters 14, 15. This protection panel 26 is more particularly positioned in the observation field CO of the observation means 11 to protect the observation means from metal vapors 55. The protection panel 26 may be in the form of a transparent or translucent plate, as illustrated in [Fig.2]. The transparent or translucent protective panel 26 allows light to pass from inside the chamber 2 of the manufacturing device 1 through the first and second openings 141, 151 of the first and second shutters 14, 15 towards the observation means 11 while preventing the metal vapors 55 generated during the metallurgical process..

[0130] The protective panel 26 may be made of glass or solid plastic. It may more particularly be in the form of a disc or a ring made of transparent or translucent material arranged so that a peripheral portion of the disc is located in the axis of the first opening 141 of the first shutter 14 and in the axis of the second opening 151 of the second shutter 15. In the specific case where the protective panel 26 is in the form of a ring, the electron beam FE can pass inside the ring and more particularly through the center of the ring. Such a protective panel 26 may be movable in rotation about an axis of rotation so that the peripheral portion which is located in the axis of the openings when these are superimposed is renewed as a function of the rotation of the protective panel 26.

[0131] According to a variant of this embodiment, the position of the protective panel 26 can be adjusted mechanically, for example during a maintenance operation. The protective panel 26 is then rotated about its axis of rotation so as to move its part potentially obscured by the metal vapors 55 out of the axis of the openings until an undamaged part of the peripheral portion of the protective panel 26 is located in the axis of the openings of the shutters 14, 15, which makes it possible to restore the quality of the images during shooting.

[0132] According to another variant of this embodiment, the protection panel 26 is configured to rotate continuously and at a slow speed around its axis of rotation. By “slow speed” is meant here a speed much lower than the rotation speed of the first shutter 14. A “slow speed” designates for example a rotation speed of the order of one revolution in ten hours. This makes it possible to maximize the service life of the protection panel 26 and makes it possible to limit interventions on the protection device 13. This variant of the protection panel 26 is notably illustrated in [Fig. 10]. In this [Fig.10], a part of the peripheral portion of the protection panel 26 bears traces of wear 27, such as traces of the residual metallization having passed through the entire protection device 13: the transparency of the protection panel 26 has been affected by the metallic vapors 55 to which this part of the peripheral portion has been exposed in the past. The rest of the peripheral portion does not yet bear any trace of the residual metallization. When the entire peripheral portion of the protection panel 26 bears traces of the residual metallization having passed through the entire protection device, cleaning of the protection panel 26 will have to be considered, or even a complete replacement of the protection panel 26 in the protection device 13 within the observation device 10.

[0133] When the manufacturing device 1 is used for implementing a manufacturing process, such as a metallurgical process generating metal vapors 55, the drive means 16 moves the first movable shutter 14 and the second movable shutter 15 so that the first opening 141 and the second opening 151 are positioned periodically and simultaneously in the observation field CO of the optical observation means 11. The optical observation means 11 of the observation device 10 takes a picture when the first opening 141 and the second opening 151 are positioned simultaneously in the observation field CO of the observation means 11. In order to obtain quality images, it is preferable for the optical observation means 11 to take twenty-five pictures per second. This is why the rotation speed of the first shutter 14 is of the order of twenty-five revolutions per second, or one thousand five hundred revolutions per minute.Furthermore, the rotation speed of the second shutter 15 is preferably an integer multiple of the speed of . rotation of the first shutter 14. Thus, the rotation speed of the second shutter 15 is for example two or three or four or five or six or seven or eight or nine times higher than the rotation speed of the first shutter 14.

[0134] In order to allow observation of the interior of the chamber 2 after a manufacturing step for example, in particular to check the result obtained, the drive means 16 of the observation device 13 can be controlled so as to slow down the movements of the first shutter 14 and of the second shutter 15 until they are completely immobilized. The adjustment means 28 described previously is then used to align the first opening 141 of the first shutter 14 with the second opening 151 of the second shutter 15 in the observation field CO of the observation means 11 when the shutters 14, 15 are immobilized.

[0135] More particularly, the alignment openings 281 arranged in an arc of a circle in the first shutter 14 make it possible to evaluate the position of the first shutter 14 relative to the second shutter 15. Thus, when all of the alignment openings 281 are located in alignment with the arc of a circle opening 282 of the second shutter 15, the first and second openings 141, 151 of the two shutters 14, 15 are positioned in the observation field CO of the observation means 11. This is notably illustrated in the first image of [Fig. 13]. When the protection device 13 is in operation, that is to say when the drive means 16 rotates the shutters 14 and 15 by means of its motor 162, it is possible to control the drive means 16 so that it reduces the rotation speed of the two shutters 14 and 15.When the rotation speed of the shutters 14 and 15 is changed, the number of alignment apertures 281 in the first shutter 14 aligned with the arcuate aperture 282 in the field of view CO of the second shutter 15 also changes.

[0136] It is then possible to control the drive means 16 of the observation device 13 so as to vary the rotation speed of the two shutters 14, 15 in order to slow down their movements until they are completely immobilized and to use the adjustment means 28 to check the positioning of the first and second openings 141, 151 of the two shutters 14, 15 in the observation field CO of the observation means 11.

[0137] Finally, thanks to the invention, it is thus possible to provide an observation device 10 for observing a metallurgical process generating metal vapors 55, remedying the known drawbacks of the prior art and improving existing devices.

Claims

Claims

1. An observation device (10) for observing a process generating metal vapors (55), the observation device comprising an optical observation means (11) and a protection device (13) positioned in an observation field (CO) of the observation means (11) to protect the observation means (11), characterized in that the protection device (13) comprises a first shutter (14) movable relative to the observation means and a second shutter (15) movable relative to the observation means (11), the first shutter (14) comprising at least one first opening (141) intended to be positioned in the observation field (CO) of the observation means (11) for a given position of the first shutter (14), the second shutter (15) comprising at least one second opening (151) intended to be positioned in the observation field (CO) of the observation means (11) for a given position of the second shutter (15),the protection device (13) further comprising a drive means (16) configured to move the first shutter (14) and the second shutter (15) so that the first opening (141) and the second opening (151) are positioned periodically and simultaneously in the field of observation (CO) of the observation means (11).,

2. Observation device according to the preceding claim, characterized in that the first shutter (14) is rotatable about a first axis of rotation (A1), in that the second shutter (15) is rotatable about a second axis of rotation (A2), and in that the drive means (16) is configured to rotate the first shutter (14) at a first speed and to rotate the second shutter (15) at a second speed, the first speed being a multiple of the second speed or the second speed being a multiple of the first speed.

3. Observation device according to the preceding claim, characterized in that the first axis of rotation (Al) coincides with the second axis of rotation (A2).

4. Observation device according to the preceding claim, characterized in that the observation field (CO) of the observation means (11) is offset relative to the axis of rotation (Al, A2) of the first (14) and second (15) shutters.

5. Observation device according to one of the preceding claims, characterized in that the first shutter (14) and the second shutter (15) are made of non-reflective materials.

6. Observation device according to one of the preceding claims, characterized in that the first shutter (14) comprises a first wall (142) in which said at least one first opening (141) is formed, the first wall (142) comprising a disc shape or a cylindrical shape or a conical shape, and / or in that the second shutter (15) comprises a second wall (152) in which said at least one second opening (151) is formed, the second wall (152) comprising a disc shape or a cylindrical shape or a conical shape.

7. Observation device according to claims 4 and 6, characterized in that the first wall (142) of the first shutter (14) and the second wall (152) of the second shutter (15) each have a cylindrical shape and in that the at least one first opening (141) and the at least one second opening (151) are offset relative to the centers of the first and second walls (142, 152) of cylindrical shape.

8. Observation device according to one of the preceding claims, characterized in that it comprises an adjustment means (28, 281, 282) configured to align the first opening (141) of the first shutter (14) with the second opening (151) of the second shutter (15) in the observation field (CO) of the observation means (11).

9. Observation device according to one of claims 2 to 8, characterized in that the first shutter (14) comprises at least one balancing means (25), in particular at least one balancing opening (251) positioned outside the field of observation (CO) of the observation means (11) regardless of the position of the first shutter (14), and / or in that the second shutter (15) comprises at least one balancing means (25), in particular at least one balancing opening (252) positioned outside the field of observation (CO) of the observation means (11) regardless of the position of the second shutter (15).

10. Observation device according to one of the preceding claims, characterized in that the protection device (13) comprises a transparent or translucent protection panel (26) arranged between the optical observation means (11) and the assembly formed by the first and the second shutters (14, 15), the protective panel (26) being positioned in the field of observation (CO) of the optical observation means (11) to protect the optical observation means (11).

11. Observation device according to the preceding claim, characterized in that the protective panel (26) is movable in rotation around an axis of rotation.

12. Manufacturing device (1) comprising a chamber (2) configured to house processes generating metal vapors (55), such as metallurgical processes, the manufacturing device also comprising an observation device (10) according to one of the preceding claims and in particular a vacuum pump (3) intended to generate a depression inside the chamber (2).

13. Manufacturing device according to the preceding claim, characterized in that it further comprises an electron gun (20) configured to produce an electron beam (FE) inside the chamber (2).

14. Method of using the observation device according to one of claims 1 to 11 or the manufacturing device (1) according to one of claims 12 or 13, characterized in that the drive means (16) moves the first movable shutter (14) and the second movable shutter (15) so that the first opening (141) and the second opening (151) are positioned periodically and simultaneously in the field of observation (CO) of the optical observation means (11) and in that the optical observation means (11) of the observation device (10) takes a picture when the first opening (141) and the second opening (151) are positioned simultaneously in the field of observation (CO) of the observation means (H).

15. Method of using the observation device according to claim 8, characterized in that the drive means (16) is controlled so as to slow down the movements of the first shutter (14) and the second shutter (15) until they are immobilized and in that the adjustment means (28) is used to align the first opening (141) of the first shutter (14) with the second opening (151) of the second shutter (15) in the field of observation (CO) of the optical observation means (11) when the shutters (14, 15) are immobilized.

Images