EP0153255A2 - Lateral electromagnetic pumping basin for a foundry furnace - Google Patents

Lateral electromagnetic pumping basin for a foundry furnace Download PDF

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Publication number
EP0153255A2
EP0153255A2 EP85400301A EP85400301A EP0153255A2 EP 0153255 A2 EP0153255 A2 EP 0153255A2 EP 85400301 A EP85400301 A EP 85400301A EP 85400301 A EP85400301 A EP 85400301A EP 0153255 A2 EP0153255 A2 EP 0153255A2
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European Patent Office
Prior art keywords
basin
liquid metal
electromagnetic
magnetic circuit
magnetic
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EP85400301A
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German (de)
French (fr)
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EP0153255A3 (en
EP0153255B1 (en
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Henri Carbonnel
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D39/00—Equipment for supplying molten metal in rations
    • B22D39/003—Equipment for supplying molten metal in rations using electromagnetic field

Definitions

  • the present invention relates to an electromagnetic furnace pumping side basin intended to transport metal in the liquid state only under the action of electromagnetic forces, to supply molds in the foundry industry in general, but more particularly in that light metals.
  • the invention consists in incorporating inside the lateral basin of an oven the magnetic elements and the liquid coil intended for pumping by integrating them into the ceramic of the oven and transferring the outside of the basin into the ambient air. electrical windings necessary for pumping.
  • FIG. 1 we describe the basic principle which is a transformer with a primary coil 1 and a secondary coil 2 full of liquid metal, open on the furnace on the front face of the coil.
  • the magnetic circuit of the transformer 3 is deformed in the lower part by partial approximation of one or more vertical legs, which will allow the passage of a horizontal leakage field, from the left leg 4 to the right leg 5 of this transformer in the close-up part, the lower horizontal branch 7 being partially short-circuited by the leakage field.
  • the oven could be heated by gas, oil or by an induction system.
  • the electromagnetic pumping system is on the right side of the oven in the side basin.
  • the liquid turn 104 in connection with the furnace by the inlet orifice 105 and connected to the outside by the conduit 106.
  • the magnetic circuit 107 is supplied by the coil 108.
  • a ceramic partition 109 separates the active vein 104 from the oven 102 to thereby limit parasitic circulation of the liquid metal between oven and active vein.
  • this active vein of the coil 104 is at an altitude higher than the bottom of the furnace and the coil 104 is inclined to descend towards this bottom of the furnace which allows the emptying of the coil.
  • FIG. 3 which is the vertical section of the pelvis at the level of the electromagnetic pumping system, we find the liquid vein 104 and we also see that the inlet vein on the right is at a lower altitude than the active vein. We also find the magnetic circuit 107 and the primary excitation coil 108. The saturation notch 110 in the magnetic circuit is shown in this figure 3. /
  • FIG. 4 which is a horizontal section of the lateral basin at the level of the coil 104, we find the magnetic circuit 107, the outlet tube 106 and the cereal partition mique 109 partially separating the liquid turn 104 from the oven 102.
  • the electromagnetic pumping system with magnetic saturation shown diagrammatically in FIG. 1 is not limiting. As an example we will give some variants of these electromagnetic pumping systems with magnetic saturation which can be placed under the ceramic of the lateral basin of the furnace, in place of the electromagnetic pumping system of FIG. 1.
  • FIG. 5 One of these variants represented in FIG. 5 consists in using a transformer with three vertical magnetic branches with the middle leg 54 passing through the center of the liquid turn 52.
  • the current in this liquid turn is induced on the one hand, by the vertical leg circuit 57 plus middle leg 54 and partially by the vertical leg circuit 53 plus middle leg 54.
  • the coil 58 will also serve to create the leakage field increased by the saturation notch 56 between the vertical leg 54 and the close portion 55 of the leg 53.
  • the two coils 51 and 58 on the upper horizontal branches can be replaced by a single coil on the central leg 54 without changing the problem.
  • FIG. 6 Another variant, represented in FIG. 6, consists in using a transformer with three vertical magnetic legs with the extreme legs locally brought together to create a pump with two liquid turns superimposed in series.
  • the two diagrams of Laplace's law show that the pumping forces are added.
  • FIG. 7 Another variant, shown in FIG. 7, consists in using the same transformer with three legs with extreme legs close to the middle leg to create a pump with parallel effects in the single turn. Each half-turn is active and rejects the metal upwards. The two outputs can be independent or connected to have the parallel effect which increases the flow.
  • the single coil on the middle leg Here we have re shown in Figure 7, the single coil on the middle leg.
  • FIG. 8 It is likewise possible to use in the same spirit as shown in FIG. 8 a simple transformer with an excitation coil 81 and two vertical legs 83 and 84 with a turn 82 and 87 around each vertical leg between which the common part 88 of these two turns 82 and 87.
  • the front face of these two turns 82 and 87 as well as the common part 88 are open on the main basin of the oven which allows their supply of liquid metal.
  • the common part 88 between the close parts of the vertical legs 83 and 84 will constitute the active vein of our electromagnetic system. In this active vein 88, the currents induced in the two turns 82 and 87 are added in value and in direction.
  • the saturation notch 86 placed here on the lower horizontal branch 89 increases the leakage field Hf.
  • saturation notch 86 can be replaced for example by a progressive narrowing of the two close parts of the two vertical legs 83 and 84, or by the narrowing of the lower horizontal branch 89 or by other known means such as that slots or holes, etc ...
  • the lateral basin of a foundry furnace can be produced with the electromagnetic pumping system, the principle of which has been shown in the figure. 8 placed in the ceramic of said lateral basin.
  • the magnetic circuit 207 is partially embedded in the ceramic with the active coil 204 and the metal outlet conduit 206.
  • the excitation coil 208 is in the ambient air.
  • the active coil 204 is in connection with the furnace 202 by the metal inlet orifice 205. This active coil of which we see in the figure, because of the section shown, only the active vein 204 and the front parts and rear of the two turns connected to this active vein 204, is at a level higher than the bottom of the oven and the partition 209 descends below the lower level of this turn to limit the parasitic movements of liquid metal between the active vein 204 and the oven 202 through hole 205.
  • FIG. 10 which is a vertical section of the basin by the axis of the magnetic circuit, we find the magnetic circuit 207 of the transformer with its excitation coil 208.
  • the active vein 204 is located between the close parts of the vertical legs of the transformer 207. Saturation is obtained here by the progressive narrowing 210 of the parts close to the vertical legs.
  • the two turns 211 and 212 with the common part 204 surround these close parts 210 of the vertical legs and are in connection with the furnace.
  • the turns 211 and 212 have a progressively increasing altitude from the level of the bottom of the oven at the inlet 205 to the level of the active vein 204 at the rear, which allows the emptying of all the liquid turns.
  • the coil 208 is shown here above the basin of the oven but it can also be placed on the side on the front of the basin for example.
  • the outlet tube 206 instead of being inclined could be vertical above the active vein 204 which would allow a pipe outlet connected to tube 206 to have any orientation.
  • FIG. 11 which is a horizontal section at the height of the active vein, to facilitate understanding, we find the magnetic circuit 207 of the transformer, the active vein 204 with the two turns 211 and 212, the partition 209 and the outlet tube 206 shown in dotted lines because it is at a level higher than the plane of the section.
  • FIG. 12 we have shown another construction variant which consists in pre-molding the electromagnetic pumping system comprising, at least part of the magnetic circuit 307 and at least part of the liquid turn 304, in an identical ceramic block 313 to that of the pelvis or different.
  • the lateral basin 315 is removable and the ceramic 324 of this lateral basin 315 is cast with an interior shape to receive the exterior shape 313 of the ceramic block comprising the electromagnetic pumping system.
  • the fixed part of the oven 316 is fixed on a frame 317 which can receive the removable basin 315.
  • the assembly of the removable basin on the oven is carried out by an ordinary screw-nut system 318 each compressing at least one spring whose role is to press another fiber or alumina felt seal 319 placed between the removable basin 315 and the oven 316.
  • the oven shown assembled and seen from above, has a removable ceramic crucible.
  • the crucible is heated for example by electric rods or again by a set of expanded metal matching the external shape of the crucible or embedded in fibers or the ceramic of the furnace.
  • Figure 14 shows the different parts of the oven disassembled.
  • the oven-electromagnetic basin assembly can be given any desirable shape to adapt it to the needs of users.
  • a cylindrical furnace is perfectly within the scope of this invention.
  • ovens can be used for all foundry uses: shell, low-pressure, die-casting machines, foundry carousels, vacuum casting with sealed oven, lost wax casting, etc. .. Indeed, such ovens replace electromagnetic ovens or pressure ovens or even the foundry, to cast the metal by gravity or reassemble it in an outlet tube to a mold placed higher or even transfer it outside out of the oven.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
  • General Induction Heating (AREA)
  • Muffle Furnaces And Rotary Kilns (AREA)
  • Fuel-Injection Apparatus (AREA)
  • Valve Device For Special Equipments (AREA)
  • Discharge Lamp (AREA)
  • Vending Machines For Individual Products (AREA)
  • Electromagnetic Pumps, Or The Like (AREA)

Abstract

The invention relates to a lateral basin for electromagnetic pumping in a foundry and in particular in a light metal foundry. The pump comprises a magnetic circuit (207) which is locally saturated and which is embedded in the ceramic of the said basin. The electrical excitation winding of the magnetic circuit (208) is located outside the basin, and the circuit is disposed to create a horizontal leakage field through an active portion (204) of a liquid metal turn which, together with electrical current induced in said active portion (204), sets up a magnetic pumping force which is upwardly directed and which urges liquid metal into a duct (206) leading away from the furnace to liquid metal receiving means. The liquid from the furnace (202) supplies the active portion of the liquid metal turn (204) via a passage (205) of height limited by a partition (209). The electromagnetic pumping basin enables almost any casting requirements in a foundry to be supplied with liquid metal.

Description

La présente invention concerne un bassin latéral de pompage électromagnétique de four destiné à véhiculer le métal à l' état liquide uniquement sous l'action des forces électromagnétiques, pour alimenter des moules dans l'industrie de la fonderie en général, mais plus particulièrement dans celle des métaux légers.The present invention relates to an electromagnetic furnace pumping side basin intended to transport metal in the liquid state only under the action of electromagnetic forces, to supply molds in the foundry industry in general, but more particularly in that light metals.

Cette utilisation des forces électromagnétiques est bien connue et a fait l'objet de nombreux brevets dans les applications aux pompes électromagnétiques que nous classerons en deux catégories.This use of electromagnetic forces is well known and has been the subject of numerous patents in applications to electromagnetic pumps which we will classify into two categories.

La première concerne les pompes destinées au sodium liquide pour les réacteurs nucléaires à neutrons rapides principalement. Elles font l'objet de la plus grande partie des brevets décernés à travers le monde sur ce sujet. Les premiers à notre connaissance datent du début du siècle et la première pompe fut construite par Hartman en 1918. Les principaux sont les brevets d'Albert Einstein et Léo Szélard pris à Berlin autour des années 30 (brevets n°555.413 Klasse 17a-groupe 304 et 476.812-Klasse 31c-groupe 26, par exemple). Le sodium circule toujours à l'abri de l'air dans un conduit généralement en acier inoxydable à bas carbone et la partie active de la pompe est construite autour de ce conduit, partie magnétique et bobinages électriques étant à l'air libre. Elles sont citées ici pour mémoire car leurs modes de construction et d'utilisation sont très éloignés de notre application bien que faisant appel aux mêmes principes pour véhiculer le métal et par conséquent nous pourrions bien évidemment appliquer sans difficulté le principe de pompage de notre brevet à ces pompes au sodium liquide.The first concerns pumps intended for liquid sodium, mainly for fast neutron nuclear reactors. They are the subject of most of the patents granted around the world on this subject. The first to our knowledge date from the beginning of the century and the first pump was built by Hartman in 1918. The main are the patents of Albert Einstein and Léo Szélard taken in Berlin around the 1930s (patents n ° 555.413 Klasse 17a-group 304 and 476,812-Klasse 31c-group 26, for example). Sodium always flows away from air in a duct generally made of low carbon stainless steel and the active part of the pump is built around this duct, the magnetic part and electrical coils being in the open air. They are cited here for the record because their methods of construction and use are very far from our application although using the same principles to transport the metal and therefore we could obviously apply without difficulty the pumping principle of our patent to these liquid sodium pumps.

La seconde concerne les pompes pour métaux fondus industriels autres que le sodium. Elles utilisent des technologies comparables à celles des fours. Nous classerons ces pompes pour métaux fondus industriels en trois catégories :

  • 1. Celles qui utilisent les lois de Lenz
  • 2. Les pompes immergées
  • 3. Les systèmes de pompage montés directement sur le four mais à l'extérieur de celui-ci.
The second concerns pumps for industrial molten metals other than sodium. They use technologies comparable to those of ovens. We will classify these industrial molten metal pumps into three categories:
  • 1. Those who use Lenz's laws
  • 2. Submersible pumps
  • 3. The pumping systems mounted directly on the furnace but outside of it.

L'invention consiste à incorporer à l'intérieur du bassin latéral d'un four les éléments magnétiques et la spire liquide destinés au pompage en les intégrant dans la céramique du four et à reporter à l'extérieur du bassin dans l'air ambiant les bobinages électriques nécessaires au pompage.The invention consists in incorporating inside the lateral basin of an oven the magnetic elements and the liquid coil intended for pumping by integrating them into the ceramic of the oven and transferring the outside of the basin into the ambient air. electrical windings necessary for pumping.

On n'a plus à craindre les fuites externes de métal puisque c'est la céramique interne du four qui entoure les circuits magnétiques et les protège du métal liquide très corrosif à ces températures. Cette céramique est généralement contenue à l'intérieur d'une cuve métallique qui la plupart du temps est elle-même étanche. Le rôle de cette cuve étanche est aussi de protéger mécaniquement la céramique du four pendant le transport ou des chocs sur place.There is no longer any fear of external metal leaks since it is the internal ceramic of the oven which surrounds the magnetic circuits and protects them from liquid metal which is very corrosive at these temperatures. This ceramic is generally contained inside a metal tank which most of the time is itself waterproof. The role of this sealed tank is also to mechanically protect the ceramic from the oven during transport or impact on site.

On peut donc ainsi intégrer dans ce bassin un ou plusieurs des systèmes électromagnétiques connus de pompage. Mais dans l'application envisagée, on utilisera plus particulièrement un système de pompage original.One can thus integrate into this basin one or more of the known electromagnetic pumping systems. However, in the envisaged application, an original pumping system will be used more particularly.

Pour faciliter la compréhension du fonctionnement de / ce système original proposé, nous allons décomposer les différentes phases par lesquelles passe l'invention pour aboutir à la solution proposée, chaque étape étant d'ailleurs une possibilité d'utilisation, mais toutes basées sur l'utilisation d'un circuit magnétique partiellement saturé.To facilitate understanding of how / this original proposed system, we are going to break down the different phases through which the invention passes to arrive at the proposed solution, each step being a possibility of use, but all based on the use of a partially saturated magnetic circuit .

Sur la figure 1, nous décrivons le principe de base qui est un transformateur avec une bobine primaire 1 et une spire secondaire 2 pleine de.métal liquide, ouverte sur le four sur la face avant de la spire. Le circuit magnétique du transformateur 3 est déformé dans la partie basse par rapprochement partiel d'une ou des jambes verticales, ce qui va permettre le passage d'un champ de fuite horizontal, de la jambe de gauche 4 vers la jambe de droite 5 de ce transformateur dans la partie rapprochée, la branche horizontale inférieure 7 étant partiellement court-circuitée par le champ de fuite.In FIG. 1, we describe the basic principle which is a transformer with a primary coil 1 and a secondary coil 2 full of liquid metal, open on the furnace on the front face of the coil. The magnetic circuit of the transformer 3 is deformed in the lower part by partial approximation of one or more vertical legs, which will allow the passage of a horizontal leakage field, from the left leg 4 to the right leg 5 of this transformer in the close-up part, the lower horizontal branch 7 being partially short-circuited by the leakage field.

Il est possible d'augmenter ce champ de fuite horizontal entre les deux jambes verticales partiellement rapprochées du transformateur en créant une saturation locale par un des moyens bien connus, tel que par exemple une encoche 6 dans une jambe de droite 5 telle que représentée sur la figure 1. Mais cela pourrait tout aussi bien être obtenu par des fentes verticales ou horizontales ou des trous à l'intérieur des circuits magnétiques ou encore par rétrécissement progressif de ces jambes verticales, ou de la branche hori- zontalé, ou encore par remplacement partiel de tôles, magnétiques à ces températures d'utilisation, par des tôles non ou moins magnétiques ou bien encore par d'autres moyens connus.It is possible to increase this horizontal leakage field between the two vertical legs partially close to the transformer by creating local saturation by one of the well-known means, such as for example a notch 6 in a right leg 5 as shown in the figure 1. But this could just as easily be obtained by vertical or horizontal slits or holes inside the magnetic circuits or by progressive narrowing of these vertical legs, or of the horizontal branch, or even by partial replacement of sheets, magnetic at these temperatures of use, by non or less magnetic sheets or even by other known means.

Cette saturation crée, donc juste au-dessus du rétrécissement 6 du circuit magnétique, le champ de fuite horizontale Hf qui ne transite pas par la branche horizontale inférieure et passe d'une jambe à l'autre du transformateur au-dessus de la saturation.This saturation creates, therefore just above the narrowing 6 of the magnetic circuit, the horizontal leakage field Hf which does not pass through the lower horizontal branch and passes from one leg to the other of the transformer above the saturation.

Ce champ de fuite Hf combiné avec le courant secondaire Is induit dans la spire liquide 2 crée une force verticale Q de pompage par application de la loi de Laplace appelée loi d'Ampère par les Anglo-Saxons.This leakage field Hf combined with the secondary current Is induced in the liquid turn 2 creates a vertical force Q of pumping by application of Laplace law called Ampère law by the Anglo-Saxons.

En pratique ce système de pompage électromagnétique dont la théorie vient d'être décrite ci-dessus est coulé dans la céramique du bassin latéral d'un four de fonderie comme représenté sur les figures 2, 3 et 4.In practice, this electromagnetic pumping system, the theory of which has just been described above, is poured into the ceramic of the lateral basin of a foundry furnace as shown in FIGS. 2, 3 and 4.

Sur la figure 2, nous avons de la gauche vers la droite, le bassin de chargement 101, le bassin de fusion ou maintien 102 et les éléments de chauffage électrique 103. Mais bien entendu, sans rien changer à l'invention, le four pourrait être à chauffage au gaz, au fuel ou encore par un système à induction. Le système de pompage électromagnétique est sur la partie droite du four dans le bassin latéral. Nous retrouvons dans ce bassin la spire liquide 104 en liaison avec le four par l'orifice d'entrée 105 et raccordée à l'extérieur par le conduit 106. Le circuit magnétique 107 est alimenté par la bobine 108. Nous remarquerons que en face de la veine active de la spire liquide 104 une cloison en céramique 109 sépare la veine active 104 du four 102 pour limiter ainsi les circulations parasites du métal liquide entre four et veine active. Ainsi cette veine active de la spire 104 est à une altitude supérieure au fond du four et la spire 104 est inclinée pour descendre vers ce fond du four ce qui permet la vidange de la spire.In FIG. 2, we have from the left to the right, the loading basin 101, the melting or holding basin 102 and the electric heating elements 103. But of course, without changing anything in the invention, the oven could be heated by gas, oil or by an induction system. The electromagnetic pumping system is on the right side of the oven in the side basin. We find in this basin the liquid turn 104 in connection with the furnace by the inlet orifice 105 and connected to the outside by the conduit 106. The magnetic circuit 107 is supplied by the coil 108. We will notice that opposite the active vein of the liquid turn 104 a ceramic partition 109 separates the active vein 104 from the oven 102 to thereby limit parasitic circulation of the liquid metal between oven and active vein. Thus this active vein of the coil 104 is at an altitude higher than the bottom of the furnace and the coil 104 is inclined to descend towards this bottom of the furnace which allows the emptying of the coil.

Sur la figure 3 qui est la coupe verticale du bassin au niveau du système de pompage électromagnétique, on retrouve la veine liquide 104 et on constate aussi que la veine d'entrée à droite est à une altitude plus faible que la veine active. On retrouve aussi le circuit magnétique 107 et la bobine d'excitation primaire 108. L'encoche de saturation 110 dans le circuit magnétique est représentée sur cette figure 3. / In FIG. 3 which is the vertical section of the pelvis at the level of the electromagnetic pumping system, we find the liquid vein 104 and we also see that the inlet vein on the right is at a lower altitude than the active vein. We also find the magnetic circuit 107 and the primary excitation coil 108. The saturation notch 110 in the magnetic circuit is shown in this figure 3. /

Sur la figure 4 qui est une coupe horizontale du bassin latéral au niveau de la spire 104, on retrouve le circuit magnétique 107, le tube de sortie 106 et la cloison de céramique 109 séparant partiellement la spire liquide 104 du four 102.In FIG. 4 which is a horizontal section of the lateral basin at the level of the coil 104, we find the magnetic circuit 107, the outlet tube 106 and the cereal partition mique 109 partially separating the liquid turn 104 from the oven 102.

Le système de pompage électromagnétique à saturation magnétique représenté schématiquement sur la figure 1 n'est pas limitatif. A titre d'exemple nous allons donner quelques variantes de ces systèmes de pompage électromagnétique à saturation magnétique qui peuvent être mis sous la céramique du bassin latéral du four, à la place du système de pompage électromagnétique de la figure 1.The electromagnetic pumping system with magnetic saturation shown diagrammatically in FIG. 1 is not limiting. As an example we will give some variants of these electromagnetic pumping systems with magnetic saturation which can be placed under the ceramic of the lateral basin of the furnace, in place of the electromagnetic pumping system of FIG. 1.

Une de ces variantes représentée figure 5 consiste à utiliser un transformateur à trois branches magnétiques verticales avec la jambe médiane 54 passant au centre de la spire liquide 52. Le courant dans cette spire liquide est induit d'une part, par le circuit jambe verticale 57 plus jambe médiane 54 et partiellement par le circuit jambe verticale 53 plus jambe médiane 54. Dans ce dernier circuit 53-54, la bobine 58 servira aussi à créer le champ de fuite augmenté par l'encoche de saturation 56 entre la jambe verticale 54 et la partie rapprochée 55 de la jambe 53. On peut remplacer les deux bobines 51 et 58 sur les branches horizontales supérieures par une seule bobine sur la jambe centrale 54 sans rien changer au problème.One of these variants represented in FIG. 5 consists in using a transformer with three vertical magnetic branches with the middle leg 54 passing through the center of the liquid turn 52. The current in this liquid turn is induced on the one hand, by the vertical leg circuit 57 plus middle leg 54 and partially by the vertical leg circuit 53 plus middle leg 54. In this last circuit 53-54, the coil 58 will also serve to create the leakage field increased by the saturation notch 56 between the vertical leg 54 and the close portion 55 of the leg 53. The two coils 51 and 58 on the upper horizontal branches can be replaced by a single coil on the central leg 54 without changing the problem.

Une autre variante, représentée figure 6, consiste à utiliser un transformateur à trois jambes magnétiques verticales avec les jambes extrêmes localement rapprochées pour créer une pompe avec deux spires liquides superposées en série. Les deux diagrammes de la loi de Laplace montrent que les forces de pompage s'ajoutent.Another variant, represented in FIG. 6, consists in using a transformer with three vertical magnetic legs with the extreme legs locally brought together to create a pump with two liquid turns superimposed in series. The two diagrams of Laplace's law show that the pumping forces are added.

De même une autre variante, représentée figure 7, consiste à utiliser le même transformateur à trois jambes à jambes extrêmes rapprochées de la jambe médiane pour créer une pompe à effets parallèles dans la spire unique. Chaque demi- spire est active et rejette le métal vers le haut. Les deux sorties peuvent être indépendantes ou reliées pour avoir l'effet parallèle qui augmente le débit. Ici nous avons représenté, sur la figure 7, la bobine unique sur la jambe médiane.Similarly, another variant, shown in FIG. 7, consists in using the same transformer with three legs with extreme legs close to the middle leg to create a pump with parallel effects in the single turn. Each half-turn is active and rejects the metal upwards. The two outputs can be independent or connected to have the parallel effect which increases the flow. Here we have re shown in Figure 7, the single coil on the middle leg.

Il est de même possible d'utiliser dans le même esprit comme représenté sur la figure 8 un transformateur simple à une bobine d'excitation 81 et deux jambes verticales 83 et 84 avec une spire 82 et 87 autour de chaque jambe verticale entre lesquelles passe la partie commune 88 de ces deux spires 82 et 87. La face avant de ces deux spires 82 et 87 ainsi que la partie commune 88 sont ouvertes sur le bassin principal du four ce qui permet leur alimentation en métal liquide. La partie commune 88 entre les parties rapprochées des jambes verticales 83 et 84 va constituer la veine active de notre système électromagnétique. Dans cette veine active 88, les courants induits dans les deux spires 82 et 87 s'ajoutent en valeur et en direction. L'encoche de saturation 86 placée ici sur la branche horizontale inférieure 89 augmente le champ de fuite Hf. Nous avons représenté le diagramme de la loi de Laplace et le sens de pompage Q est aussi dirigé vers le haut.It is likewise possible to use in the same spirit as shown in FIG. 8 a simple transformer with an excitation coil 81 and two vertical legs 83 and 84 with a turn 82 and 87 around each vertical leg between which the common part 88 of these two turns 82 and 87. The front face of these two turns 82 and 87 as well as the common part 88 are open on the main basin of the oven which allows their supply of liquid metal. The common part 88 between the close parts of the vertical legs 83 and 84 will constitute the active vein of our electromagnetic system. In this active vein 88, the currents induced in the two turns 82 and 87 are added in value and in direction. The saturation notch 86 placed here on the lower horizontal branch 89 increases the leakage field Hf. We have represented the diagram of Laplace's law and the direction of pumping Q is also directed upwards.

Nous rappelons que l'encoche de saturation 86 peut être remplacée par exemple par un rétrécissement progressif des deux parties rapprochées des deux jambes verticales 83 et 84, ou encore par le rétrécissement de la branche horizontale inférieure 89 ou encore par d'autres moyens connus tels que fentes ou trous, etc...We recall that the saturation notch 86 can be replaced for example by a progressive narrowing of the two close parts of the two vertical legs 83 and 84, or by the narrowing of the lower horizontal branch 89 or by other known means such as that slots or holes, etc ...

Cette description des exemples d'utilisation de la saturation locale pour réaliser des systèmes de pompage électromagnétique n'est évidemment pas limitative car, bien sur, d'autres applications entrant dans le cadre de l'invention en découlent pour l'homme de l'art, telles que par exemple, des transformateurs à plusieurs jambes avec plusieurs spires avec effets parallèles ou séries à plusieurs étages.This description of the examples of use of local saturation to produce electromagnetic pumping systems is obviously not limiting since, of course, other applications within the scope of the invention result for the man of the art, such as for example, transformers with several legs with several turns with parallel effects or series with several stages.

Dans la pratique, le bassin latéral d'un four de fonderie pourra être réalisé avec le système électromagnétique de pompage, dont le principe a été représenté sur la figure 8 placé dans la céramique de ce dit bassin latéral.In practice, the lateral basin of a foundry furnace can be produced with the electromagnetic pumping system, the principle of which has been shown in the figure. 8 placed in the ceramic of said lateral basin.

Sur la ligne 9 pour simplifier, nous n'avons pas représenté le four entier, mais seulement une faible partie accolée au bassin latéral qui fait seul l'objet de l'invention. Le circuit magnétique 207 est partiellement noyé dans la céramique avec la spire active 204 et le conduit de sortie du métal 206. La bobine d'excitation 208 est dans l'air ambiant. La spire active 204 est en liaison avec le four 202 par l'orifice d'entrée du métal 205. Cette spire active dont on ne voit sur la figure, à cause de la coupe représentée, que la veine active 204 et les parties avant et arrière des deux spires reliées à cette veine active 204, est à un niveau supérieur au fond du four et la cloison 209 descend en-dessous du niveau inférieur de cette spire pour limiter les mouvements parasites de métal liquide entre la veine active 204 et le four 202 à travers l'orifice 205.On line 9 for simplicity, we have not shown the entire oven, but only a small part attached to the lateral basin which is the subject of the invention alone. The magnetic circuit 207 is partially embedded in the ceramic with the active coil 204 and the metal outlet conduit 206. The excitation coil 208 is in the ambient air. The active coil 204 is in connection with the furnace 202 by the metal inlet orifice 205. This active coil of which we see in the figure, because of the section shown, only the active vein 204 and the front parts and rear of the two turns connected to this active vein 204, is at a level higher than the bottom of the oven and the partition 209 descends below the lower level of this turn to limit the parasitic movements of liquid metal between the active vein 204 and the oven 202 through hole 205.

Sur la figure 10 qui est une coupe verticale du bassin par l'axe du circuit magnétique, nous retrouvons le circuit magnétique 207 du transformateur avec sa bobine d'excitation 208. La veine active 204 est située entre les parties rapprochées des jambes verticales du transformateur 207. La saturation est obtenue ici par le rétrécissement progressif 210 des parties rapprochées des jambes verticales. Les deux spires 211 et 212 avec la partie commune 204 entourent ces parties rapprochées 210 des jambes verticales et sont en liaison avec le four. Les spires 211 et 212 ont une altitude progressivement croissante depuis le niveau du fond du four à l'entrée 205 jusqu'au niveau de la veine active 204 à l'arrière, ce qui permet la vidange de l'ensemble des spires liquides.In FIG. 10 which is a vertical section of the basin by the axis of the magnetic circuit, we find the magnetic circuit 207 of the transformer with its excitation coil 208. The active vein 204 is located between the close parts of the vertical legs of the transformer 207. Saturation is obtained here by the progressive narrowing 210 of the parts close to the vertical legs. The two turns 211 and 212 with the common part 204 surround these close parts 210 of the vertical legs and are in connection with the furnace. The turns 211 and 212 have a progressively increasing altitude from the level of the bottom of the oven at the inlet 205 to the level of the active vein 204 at the rear, which allows the emptying of all the liquid turns.

La bobine 208 est représentée ici au-dessus du bassin du four mais elle peut aussi bien être placée sur le côté sur l'avant du bassin par exemple. Dans ce cas, le tube de sortie 206 au lieu d'être incliné pourrait être vertical au-dessus de la veine active 204 ce qui permettrait à un tuyau de sortie raccordé au tube 206 d'avoir une orientation quelconque.The coil 208 is shown here above the basin of the oven but it can also be placed on the side on the front of the basin for example. In this case, the outlet tube 206 instead of being inclined could be vertical above the active vein 204 which would allow a pipe outlet connected to tube 206 to have any orientation.

On peut de même dédoubler la bobine 208 pour dégager le dessus du bassin et placer les deux bobines de chaque côté du four sans sortir de l'invention.It is also possible to split the coil 208 to release the top of the basin and place the two coils on each side of the oven without departing from the invention.

Sur la figure 11 qui est une coupe horizontale à hauteur de la veine active, pour faciliter la compréhension, nous retrouvons le circuit magnétique 207 du transformateur, la veine active 204 avec les deux spires 211 et 212, la cloison 209 et le tube de sortie 206 représenté en pointillé car il est à un niveau supérieur au plan de la coupe.In FIG. 11 which is a horizontal section at the height of the active vein, to facilitate understanding, we find the magnetic circuit 207 of the transformer, the active vein 204 with the two turns 211 and 212, the partition 209 and the outlet tube 206 shown in dotted lines because it is at a level higher than the plane of the section.

Sur la figure 12, nous avons représenté une autre variante de construction qui consiste à prémouler le système de pompage électromagnétique comprenant, une partie au moins du circuit magnétique 307 et au moins une partie de la spire liquide 304, dans un bloc de céramique 313 identique à celle du bassin ou différente. Le bassin latéral 315 est amovible et la céramique 324 de ce bassin latéral 315 est coulée avec une forme intérieure pour recevoir la forme extérieure 313 du bloc de céramique comprenant le système de pompage électromagnétique. On placera entre la céramique du bassin et celle du système électromagnétique une feuille souple de fibre ou de feutre d'alumine du commerce 314 qui facilitera le démontage et évitera la progression d'une fuite éventuelle de métal liquide.In FIG. 12, we have shown another construction variant which consists in pre-molding the electromagnetic pumping system comprising, at least part of the magnetic circuit 307 and at least part of the liquid turn 304, in an identical ceramic block 313 to that of the pelvis or different. The lateral basin 315 is removable and the ceramic 324 of this lateral basin 315 is cast with an interior shape to receive the exterior shape 313 of the ceramic block comprising the electromagnetic pumping system. Between the ceramic basin and that of the electromagnetic system, place a flexible sheet of commercial alumina fiber or felt 314 which will facilitate disassembly and prevent the progression of any leakage of liquid metal.

La partie fixe du four 316 est fixée sur un châssis 317 qui peut recevoir le bassin amovible 315. L'assemblage du bassin amovible sur le four est réalisé par un système ordinaire vis-écrous 318 comprimant chacun au moins un ressort dont le rôle est de presser un autre joint en fibre ou feutre d'alumine 319 placé entre le bassin amovible 315 et le four 316.The fixed part of the oven 316 is fixed on a frame 317 which can receive the removable basin 315. The assembly of the removable basin on the oven is carried out by an ordinary screw-nut system 318 each compressing at least one spring whose role is to press another fiber or alumina felt seal 319 placed between the removable basin 315 and the oven 316.

Sur la figure 13, le four, représenté assemblé et vu par-dessus, est à creuset amovible en céramique. Le creuset est chauffé par exemple par des baguettes électriques ou encore par un ensemble de métal déployé épousant la forme extérieure du creuset ou noyé dans des fibres ou la céramique du four.In FIG. 13, the oven, shown assembled and seen from above, has a removable ceramic crucible. The crucible is heated for example by electric rods or again by a set of expanded metal matching the external shape of the crucible or embedded in fibers or the ceramic of the furnace.

La figure 14 représente les différentes pièces du four démontées.Figure 14 shows the different parts of the oven disassembled.

Nous avons donné au four représenté une forme rectangulaire, mais bien entendu, on peut donner à l'ensemble four- bassin électromagnétique toute forme désirable pour l'adapter aux besoins des utilisateurs. En particulier, un four de forme cylindrique entre parfaitement dans le cadre de cette invention.We have given the oven shown a rectangular shape, but of course, the oven-electromagnetic basin assembly can be given any desirable shape to adapt it to the needs of users. In particular, a cylindrical furnace is perfectly within the scope of this invention.

De même, le fait d'utiliser sur un même four plusieurs bassins électromagnétiques ou plusieurs systèmes électromagnétiques par bassin, ne sort pas non plus du cadre de cette invention four avec bassin électromagnétique latéral intégré.Similarly, the fact of using on the same oven several electromagnetic basins or several electromagnetic systems per basin, does not depart from the scope of this invention oven with integrated lateral electromagnetic basin.

Il coule de source, évidemment, que de tels fours peuvent servir pour toutes les utilisations en fonderie : coquille, basse-pression, machines à couler sous pression, carrousels de fonderie, coulée sous vide avec four étanche, coulée en cire perdue, etc... En effet, de tels fours remplacent les fours électromagnétiques ou les fours sous pression ou même le fondeur, pour couler le métal par gravité ou le remonter dans un tube de sortie vers un moule placé plus haut ou même le transférer à l'extérieur hors du four.It goes without saying, of course, that such ovens can be used for all foundry uses: shell, low-pressure, die-casting machines, foundry carousels, vacuum casting with sealed oven, lost wax casting, etc. .. Indeed, such ovens replace electromagnetic ovens or pressure ovens or even the foundry, to cast the metal by gravity or reassemble it in an outlet tube to a mold placed higher or even transfer it outside out of the oven.

Claims (7)

1. Bassin latéral de four de fonderie caractérisé en ce qu'il est doté d'un système électromagnétique de pompage dont les bobinages d'excitation électrique sont rejetés dans l'air ambiant et en ce que au moins une partie du circuit magnétique et au moins l'une des veines de ce métal liquide destinée au pompage sont logées dans la céramique dudit bassin.1. Lateral basin of foundry furnace, characterized in that it is provided with an electromagnetic pumping system, the electrical excitation coils of which are discharged into the ambient air and in that at least part of the magnetic circuit and at at least one of the veins of this liquid metal intended for pumping are housed in the ceramic of said basin. 2. bassin selon la revendication 1, caractérisé en ce que le circuit magnétique comporte une partie magnétiquement saturée.2. basin according to claim 1, characterized in that the magnetic circuit comprises a magnetically saturated part. 3. Bassin selon la revendication 2, caractérisé en ce que la partie saturée du circuit magnétique est située au niveau d'un rapprochement local des branches verticales du circuit magnétique, développant ainsi entre lesdites branches un champ de fuite magnétique à travers l'une au moins des veines de métal liquide parcourue par un courant électrique induit.3. Basin according to claim 2, characterized in that the saturated part of the magnetic circuit is located at a local approximation of the vertical branches of the magnetic circuit, thus developing between said branches a magnetic leakage field through one at less of the veins of liquid metal traversed by an induced electric current. 4. Bassin selon la revendication 3, caractérisé en ce que le système électromagnétique de pompage utilise deux spires liquides secondaires accolées, dont la partie commune centrale formant la veine active, placée entre les branches rapprochées localement d'un circuit magnétique d'alimentation avec saturation locale est traversée par le champ électromagnétique de fuite entre les branches verticales du circuit magnétique et que ce champ de fuite combiné au courant induit dans la veine active liquide crée la force de pompage du métal liquide.4. Basin according to claim 3, characterized in that the electromagnetic pumping system uses two contiguous secondary liquid turns, of which the central common part forming the active vein, placed between the branches close together locally of a magnetic supply circuit with saturation the electromagnetic leakage field between the vertical branches of the magnetic circuit is crossed by it and that this leakage field combined with the current induced in the active liquid stream creates the pumping force of the liquid metal. 5. Bassin selon les revendications 1, 2, 3 et 4 caractérisé en ce que ledit bassin est démontable.5. Basin according to claims 1, 2, 3 and 4 characterized in that said basin is removable. 6. Bassin selon les revendications 1, 2 et 3 caractérisé en ce que au moins une partie des circuits magnétiques actifs du système électromagnétique et au moins l'une des veines de métal liquide sont logés dans un bloc de céramique prémoulée logé lui-même dans la céramique du four pour pouvoir être démontée.6. Basin according to claims 1, 2 and 3 characterized in that at least part of the active magnetic circuits of the electromagnetic system and at least one of the liquid metal veins are housed in a pre-molded ceramic block housed itself in the ceramic of the oven to be able to be dismantled. 7. Bassin selon les revendications 1, 2, 3, 4, 5 et 6 caractérisé en ce que au moins deux systèmes électromagnétiques de pompage sont logés dans ce dit bassin.7. Basin according to claims 1, 2, 3, 4, 5 and 6 characterized in that at least two electromagnetic pumping systems are housed in this said basin.
EP85400301A 1984-02-20 1985-02-20 Lateral electromagnetic pumping basin for a foundry furnace Expired - Lifetime EP0153255B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85400301T ATE58317T1 (en) 1984-02-20 1985-02-20 SUB-TANK FOR ELECTROMAGNETIC PUMPING FOR FOUNDRY FURNACES.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8402492A FR2559885B1 (en) 1984-02-20 1984-02-20 ELECTROMAGNETIC PUMP SIDE BASIN FOR FOUNDRY OVEN
FR8402492 1984-02-20

Publications (3)

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EP0153255A2 true EP0153255A2 (en) 1985-08-28
EP0153255A3 EP0153255A3 (en) 1987-09-02
EP0153255B1 EP0153255B1 (en) 1990-11-14

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EP (1) EP0153255B1 (en)
JP (1) JPS60247462A (en)
AT (1) ATE58317T1 (en)
DE (1) DE3580492D1 (en)
FR (1) FR2559885B1 (en)

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Publication number Priority date Publication date Assignee Title
CN101018005B (en) * 2007-02-15 2011-06-29 沈阳铝镁设计研究院有限公司 DC electromagnetic pump
CN101063211B (en) * 2007-05-15 2010-11-03 沈阳铝镁设计研究院 Direct-current electromagnetic pump for aluminum cell
JP6338650B2 (en) 2013-03-11 2018-06-06 ノベリス・インコーポレイテッドＮｏｖｅｌｉｓ Ｉｎｃ． Magnetic pump equipment

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US2224982A (en) * 1939-03-10 1940-12-17 Whitehall Patents Corp Method of die casting by electrical induction
FR949066A (en) * 1946-07-12 1949-08-19 Nat Smelting Co Advanced pump for lifting and transporting molten metals
US2707718A (en) * 1948-05-26 1955-05-03 Ajax Engineering Corp Induction pump for casting molten metals
FR2441946A1 (en) * 1978-11-15 1980-06-13 Novatome Ind CONDUCTION PUMP FOR LIQUID METAL
EP0021920A1 (en) * 1979-06-07 1981-01-07 Novatome Electromagnetic conduction pump for liquid metal
EP0058114A1 (en) * 1981-02-04 1982-08-18 Novatome Electromagnetic conduction pumps for liquid metals

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GB1192931A (en) * 1966-11-09 1970-05-28 Ass Elect Ind Improvements relating to Metal Treatment Apparatus
US3844453A (en) * 1973-01-05 1974-10-29 Modern Equipment Co Apparatus and method for melting and pouring metal

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2224982A (en) * 1939-03-10 1940-12-17 Whitehall Patents Corp Method of die casting by electrical induction
FR949066A (en) * 1946-07-12 1949-08-19 Nat Smelting Co Advanced pump for lifting and transporting molten metals
US2707718A (en) * 1948-05-26 1955-05-03 Ajax Engineering Corp Induction pump for casting molten metals
FR2441946A1 (en) * 1978-11-15 1980-06-13 Novatome Ind CONDUCTION PUMP FOR LIQUID METAL
EP0021920A1 (en) * 1979-06-07 1981-01-07 Novatome Electromagnetic conduction pump for liquid metal
EP0058114A1 (en) * 1981-02-04 1982-08-18 Novatome Electromagnetic conduction pumps for liquid metals

Also Published As

Publication number Publication date
JPS60247462A (en) 1985-12-07
FR2559885A1 (en) 1985-08-23
FR2559885B1 (en) 1988-06-10
EP0153255A3 (en) 1987-09-02
US4586698A (en) 1986-05-06
DE3580492D1 (en) 1990-12-20
ATE58317T1 (en) 1990-11-15
EP0153255B1 (en) 1990-11-14

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