EP0270466A1 - Pressure die casting machine for metallic articles which may contain ceramic fibres - Google Patents

Pressure die casting machine for metallic articles which may contain ceramic fibres Download PDF

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Publication number
EP0270466A1
EP0270466A1 EP87420297A EP87420297A EP0270466A1 EP 0270466 A1 EP0270466 A1 EP 0270466A1 EP 87420297 A EP87420297 A EP 87420297A EP 87420297 A EP87420297 A EP 87420297A EP 0270466 A1 EP0270466 A1 EP 0270466A1
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EP
European Patent Office
Prior art keywords
container
piston
metal
pressure
piping
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP87420297A
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German (de)
French (fr)
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EP0270466B1 (en
Inventor
Jean Charbonnier
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Rio Tinto France SAS
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Aluminium Pechiney SA
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Publication date
Application filed by Aluminium Pechiney SA filed Critical Aluminium Pechiney SA
Priority to AT87420297T priority Critical patent/ATE46640T1/en
Publication of EP0270466A1 publication Critical patent/EP0270466A1/en
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Publication of EP0270466B1 publication Critical patent/EP0270466B1/en
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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
    • B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
    • B22D17/20—Accessories: Details
    • B22D17/30—Accessories for supplying molten metal, e.g. in rations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
    • B22D17/02—Hot chamber machines, i.e. with heated press chamber in which metal is melted
    • B22D17/04—Plunger machines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
    • B22D17/08—Cold chamber machines, i.e. with unheated press chamber into which molten metal is ladled
    • B22D17/12—Cold chamber machines, i.e. with unheated press chamber into which molten metal is ladled with vertical press motion
    • 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
    • B22D39/06—Equipment for supplying molten metal in rations having means for controlling the amount of molten metal by controlling the pressure above the molten metal

Definitions

  • the present invention relates to a machine for the pressure molding of metal parts, in particular of aluminum and lithium alloys or of magnesium alloys, said alloys possibly containing ceramic fibers.
  • the metal is supplied to the container by detachment from the injection system of the mold and then, inclination relative to the vertical. and filling the container with a ladle. It is obvious that by operating in this way, it is not possible to obtain suitable parts from very easily oxidizable alloys.
  • the USP 3058179 had already, for an entirely different purpose, produced a machine which partially addresses the interaction problem.
  • the container is here supplied, sheltered from air, by means of a piping plunging into a sealed container containing the metal to be molded in the liquid state and provided at its upper part with an inlet for pressurized inert gas by means of which an overpressure is created on the surface of the liquid to send the latter into the container.
  • the air contained in the cylinder where the piston slides and which surrounds the piston rod is found to be put in relation with the liquid supply piping to the container.
  • the metal contained in the piping begins to flow back towards the container, it sucks this air and is thus oxidized.
  • the length of the piston must be greater than the height of the orifice connecting the piping with the container so that the metal is forced back before the cylinder is connected to the piping. Subsequently, when the piston goes down and unmask the orifice, the gas blown then under low pressure will enter the container and prevent any entry of air from the mold which is then opened and this until the value of P2 which has been reduced to 0 to facilitate the return of the metal to the container increases again to start a new molding cycle.
  • a kind of pocket placed on top of the piping and inside which a gas blanket is kept to prevent the entry of metal into the system. insufflation.
  • This pocket is equipped with a probe which detects an abnormal reduction in the height of the gas mattress and then commands the opening of a special valve responsible for ensuring the additional pressure necessary to maintain the desired height.
  • suitable pressure differences P1 and P2 is obtained using a differential pressure gauge controlled by a feeler or any position detector and which acts on the opening or closing of suitable valves.
  • the value of P2 must be at least equal to the value of the metallostatic pressure exerted by the metal when it fills the imprint. As for the difference P1 - P2 it is of the order of 0.01 MPa.
  • FIG. 1 a distinction is made between the fixed lower plate 1 and the mobile upper plate 2 of a vertical die-casting machine. Between these plates is placed the mold 3 having an imprint 4.
  • the lower plate is equipped with an injection device constituted by the container 5 in which the piston 6 slides, supported by the rod 7 which moves back and forth under the effect of the jack 18.
  • Said container is connected via the orifice 8 to the piping 9 which plunges into the bath 10 of metal to be molded contained in the crucible 11 placed in the sealed container 12 which can be pressurized by means of the gas inlet 13 in order to send the metal through the piping 9 to the container 5.
  • an inert gas is blown into the pipe 14 at a point 15 of the piping 9 according to a pressure linked to the pressure prevailing in the container as a function of the position of the piston detected by the probe 17, pressure which can be controlled by the differential pressure gauge 16.
  • Figure 2 we find the elements of Figure 1 namely the container 5, the piston 6, the rod 7, the orifice 8, the piping 9, the metal bath 10, the crucible 11, the container 12, l gas inlet 13, the pipe 14, the blowing point 15, the pressure gauge 16 and the probe 17.
  • the solenoid valve 29 the opening of which allows a high flow of blown gas .
  • the flow regulator 30 the non-return valve 31 .
  • the flow meter 32 the solenoid valve 33 which stops or passes the gas supplied to 15 .
  • the solenoid valve 34 with its flow regulator 35 which due to a failure of the blown gas circuit opens only if the probe 36 indicates a rise in metal at point 15 and the risk of blockage of the pipe .
  • the molding cycle is then restarted.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)
  • Pistons, Piston Rings, And Cylinders (AREA)
  • Actuator (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Braking Arrangements (AREA)

Abstract

L'invention est relative à une machine de moulage sous pression de pièces métalliques contenant éventuellement des fibres en céramiques. Elle s'applique au moulage dans une machine à chambre froide où la pression est exercée sur le métal contenu dans l'empreinte (4) d'un moule (3) au moyen d'un piston (6) et dans laquelle le métal à mouler est amené dans le conteneur (5) de la presse au moyen d'une tuyauterie (9) plongeant dans un bain (10) liquide dudit métal placé dans un récipient (12) étanche à l'intérieur duquel on crée une surpression P2. Elle est caractérisée en ce que la tuyauterie (9) est équipée en un point (15) de sa paroi voisin du conteneur (5) d'une alimentation en gaz inerte (14) et d'une poche sous pression P1 dépendant de la position du piston (6) et de P2. Elle trouve son application dans le moulage notamment de métaux et alliages sensibles à l'oxydation.The invention relates to a machine for the pressure molding of metal parts possibly containing ceramic fibers. It applies to molding in a cold room machine where the pressure is exerted on the metal contained in the cavity (4) of a mold (3) by means of a piston (6) and in which the metal to molding is brought into the container (5) of the press by means of a pipe (9) immersed in a bath (10) liquid of said metal placed in a sealed container (12) inside which an overpressure P2 is created. It is characterized in that the piping (9) is equipped at a point (15) on its wall near the container (5) with an inert gas supply (14) and a pressure bag P1 depending on the position piston (6) and P2. It finds its application in the molding in particular of metals and alloys sensitive to oxidation.

Description

La présente invention est relative à une machine de moulage sous pression de pièces métalliques, notamment, en alliages d'aluminium et de lithium ou en alliages de magnésium, lesdits alliages contenant éventuellement des fibres en céramiques.The present invention relates to a machine for the pressure molding of metal parts, in particular of aluminum and lithium alloys or of magnesium alloys, said alloys possibly containing ceramic fibers.

L'homme de l'art du moulage en moule permanent connait bien les procédés de moulage sous pression de pièces métalliques mettant en oeuvre notamment des machines à chambre froide dans lesquelles un alliage à l'état liquide, placé dans un conteneur solidaire d'un moule, est poussé par un piston dans une empreinte en un temps relativement court.Those skilled in the art of permanent mold molding know well the methods of pressure molding of metal parts using in particular cold room machines in which an alloy in the liquid state, placed in a container secured to a mold, is pushed by a piston into a cavity in a relatively short time.

L'exercice d'une pression pouvant dépasser 10² MPa assure ensuite l'alimentation de la pièce en alliage liquide pendant sa solidification.The exercise of a pressure which can exceed 10² MPa then ensures the supply of the part in liquid alloy during its solidification.

De tels procédés permettent d'obtenir des pièces de grande précision dimensionnelle avec un très bon état de surface, ce qui évite de recourir ultérieurement à un usinage coûteux. De plus, l'absence de masselottes conduit à une mise au mille bien meilleure que dans la coulée par gravité. Enfin, il n'est pas nécessaire de procéder à des traitements thermiques en raison des bonnes caractéristiques mécaniques présentées par les pièces brutes de moulage.Such methods make it possible to obtain parts with high dimensional accuracy with a very good surface condition, which avoids the need for costly machining later. In addition, the absence of weights leads to a much better mileage than in gravity casting. Finally, it is not necessary to carry out heat treatments because of the good mechanical characteristics presented by the raw molding parts.

Tous ces avantages font du moulage sous pression un procédé de plus en plus utilisé notamment dans les fonderies de métaux légers tels que l'aluminium et le magnésium.All of these advantages make pressure molding an increasingly used process, particularly in the foundries of light metals such as aluminum and magnesium.

Cependant, certaines, difficultés sont apparues lors de l'extension de ce procédé de moulage à de nouveaux produits tels que, par exemple, les alliages d'aluminium-lithium, certains alliages de magnésium et les produits composites contenant, outre ces métaux, des fibres en céramiques.However, certain difficulties appeared during the extension of this molding process to new products such as, for example, aluminum-lithium alloys, certain magnesium alloys and composite products containing, in addition to these metals, ceramic fibers.

On sait, en effet, que les alliages d'aluminium-lithium et de magnésium sont particulièrement sensibles à l'oxydation et que la liaison fibre-­métal dans les composites peut être fortement affaiblie par la présence dans le métal d'oxydes ou autres composés résultant d'une action de l'environnement.It is known, in fact, that aluminum-lithium and magnesium alloys are particularly sensitive to oxidation and that the fiber-metal bond in composites can be greatly weakened by the presence in the metal of oxides or other compounds resulting from an action of the environment.

Or, la plupart des machines de moulage sous pression à chambre froide n'ont pas, jusqu'à présent, pris en compte cette intéraction entre les produits moulés et l'air.However, most cold room pressure molding machines have not, until now, taken into account this interaction between the molded products and the air.

C'est ainsi, par exemple, que dans la machine de moulage sous pression décrite dans le brevet US 4088178, l'alimentation en métal du conteneur s'effectue par désolidarisation du système d'injection du moule puis, inclinaison par rapport à la verticale et remplissage du conteneur à l'aide d'une louche. Il est évident, qu'en opérant de cette façon, on ne peut pas obtenir de pièces convenables à partir d'alliages très facilement oxydables.Thus, for example, in the pressure molding machine described in US Pat. No. 4,088,178, the metal is supplied to the container by detachment from the injection system of the mold and then, inclination relative to the vertical. and filling the container with a ladle. It is obvious that by operating in this way, it is not possible to obtain suitable parts from very easily oxidizable alloys.

Antérieurement au brevet précédent, l'USP 3058179 avait déjà, dans un but tout à fait différent, réalisé une machine qui répond en partie au problème d'intéraction. En effet, le conteneur est ici alimenté à l'abri de l'air par l'intermédiaire d'une tuyauterie plongeant dans un récipient étanche contenant le métal à mouler à l'état liquide et muni à sa partie supérieure d'une arrivée de gaz inerte sous pression au moyen de laquelle on crée une surpression à la surface du liquide pour envoyer ce dernier dans le conteneur. Suivant cette disposition, on évite le contact du métal liquide, avec l'atmosphère au moment du remplissage du conteneur, mais, on ne résout pas pour autant le problème d'intéraction. En effet, lors du mouvement vers le haut du piston dans le conteneur, afin de comprimer le métal dans l'empreinte, l'air contenu dans le cylindre où coulisse le piston et qui entoure la tige du piston, se trouve être mis en relation avec la tuyauterie d'amenée de liquide au conteneur. Comme à cet instant le métal contenu dans la tuyauterie commence à refluer vers le récipient, il aspire cet air et se trouve ainsi oxydé.Prior to the previous patent, the USP 3058179 had already, for an entirely different purpose, produced a machine which partially addresses the interaction problem. In fact, the container is here supplied, sheltered from air, by means of a piping plunging into a sealed container containing the metal to be molded in the liquid state and provided at its upper part with an inlet for pressurized inert gas by means of which an overpressure is created on the surface of the liquid to send the latter into the container. According to this arrangement, contact of the liquid metal is avoided with the atmosphere when the container is filled, but the interaction problem is not solved. Indeed, during the upward movement of the piston in the container, in order to compress the metal in the impression, the air contained in the cylinder where the piston slides and which surrounds the piston rod, is found to be put in relation with the liquid supply piping to the container. As at this instant the metal contained in the piping begins to flow back towards the container, it sucks this air and is thus oxidized.

Une autre difficulté plus préoccupante encore est la suivante : étant donnée la grande vitesse de déplacement du piston (plus de 0,5 m/sec), la mise en liaison de la tuyauterie avec l'atmosphère du cylindre du piston est très rapide de sorte qu'initialement le métal n'a pas encore commencé son reflux vers le récipient lorsque cette liaison s'effectue. Il en résulte alors un écoulement de métal à l'intérieur du cylindre qui compromet rapidement la bonne marche du piston et aboutit le plus souvent à un arrêt de la machine. C'est pour parer à ces difficultés que la demanderesse a cherché et trouvé une nouvelle machine.Another even more worrying difficulty is the following: given the high speed of displacement of the piston (more than 0.5 m / sec), the connection of the piping with the atmosphere of the piston cylinder is very rapid so that initially the metal did not still started to flow back to the container when this connection is made. This then results in a flow of metal inside the cylinder which quickly compromises the smooth running of the piston and most often results in a stop of the machine. It was to overcome these difficulties that the plaintiff sought and found a new machine.

Celle-ci s'inscrit dans le cadre du brevet US 3058179, c'est-à-dire qu'elle combine au dispositif de moulage sous pression une alimentation en métal par l'intermédiaire d'une tuyauterie plongeant dans un récipient duquel le métal est refoulé vers le conteneur par l'action d'une pression P2 de gaz. Elle est caractérisée en ce que ladite tuyauterie est équipée en un point de sa paroi voisin du conteneur d'une alimentation en gaz inerte et d'une poche sous pression P1 dépendant de la position du piston et de P2.This falls within the framework of US Pat. No. 3,058,179, that is to say that it combines with the die-casting device a supply of metal by means of a pipe plunging into a container of which the metal is pushed back towards the container by the action of a pressure P2 of gas. It is characterized in that said piping is equipped at a point on its wall adjacent to the container with an inert gas supply and with a pressure bag P1 depending on the position of the piston and P2.

Dans ces conditions, en supposant le moule prêt à être alimenté, le moulage se déroule de la façon suivante : du gaz inerte est insufflé sous une pression P₁ dans la tuyauterie. Comme le piston est alors en position basse, la liaison entre le conteneur et la tuyauterie existe et ce gaz peut se répandre jusque dans l'empreinte du moule le purgeant ainsi de l'air qu'il contient.Under these conditions, assuming the mold ready to be supplied, the molding takes place as follows: inert gas is blown under a pressure P₁ in the piping. As the piston is then in the low position, the connection between the container and the piping exists and this gas can spread into the mold cavity thereby purging it of the air it contains.

Puis, une surpression est établie à la surface du bain de métal contenu dans le récipient. Pour que le métal monte dans la tuyauterie, il faut alors que cette surpression P₂ soit supérieure à P₁. Lorsque le métal a rempli la tuyauterie, et le conteneur, le piston s'élève rapidement pour assurer la compression du métal. Dès que le piston masque l'orifice de liaison entre la tuyauterie et le conteneur, ce qui est détecté au moyen d'un palpeur ou d'un détecteur quelconque, on insuffle immédiatement le gaz de manière que P₁ devienne supérieur à P₂. A ce moment, le métal est refoulé vers le récipient et on empêche tout écoulement de métal vers le cylindre au moment où la tige du piston apparaît au niveau de l'orifice. Ce gaz remplit alors tout le volume liassé entre le métal et sa pression refoule l'air qui provient du cylindre du piston. Il est à noter que la longeur du piston doit être supérieure à la hauteur de l'orifice mettant en relation la tuyauterie avec le conteneur afin que le métal soit refoulé avant que le cylindre soit mis en relation avec la tuyauterie. Par la suite, quand le piston va redescendre et démasquer l'orifice, le gaz soufflé alors sous faible pression va s'introduire dans le conteneur et empêcher tout entrée d'air provenant du moule qui est alors ouvert et ce jusqu'à ce que la valeur de P₂ qui a été réduite à 0 pour faciliter le retour du métal au récipient réaugmente pour démarrer un nouveau cycle de moulage.Then, an overpressure is established on the surface of the metal bath contained in the container. In order for the metal to rise in the pipework, this overpressure P sur must then be greater than P₁. When the metal has filled the piping, and the container, the piston rises quickly to ensure the compression of the metal. As soon as the piston masks the connection orifice between the piping and the container, which is detected by means of a probe or any detector, the gas is immediately blown in such a way that P₁ becomes greater than P₂. At this time, the metal is discharged towards the container and any flow of metal towards the cylinder is prevented at the moment when the piston rod appears at the level of the orifice. This gas then fills the entire volume bonded between the metal and its pressure expels the air which comes from the piston cylinder. It should be noted that the length of the piston must be greater than the height of the orifice connecting the piping with the container so that the metal is forced back before the cylinder is connected to the piping. Subsequently, when the piston goes down and unmask the orifice, the gas blown then under low pressure will enter the container and prevent any entry of air from the mold which is then opened and this until the value of P₂ which has been reduced to 0 to facilitate the return of the metal to the container increases again to start a new molding cycle.

Par ailleurs, il a été prévu au point d'insufflation du gaz une espèce de poche placée sur le dessus de la tuyauterie et à l'intérieur de laquelle un matelas de gaz est maintenu pour empêcher l'entrée de métal dans le système d'insufflation. Cette poche est équipée d'une sonde qui détecte une réduction anormale de la hauteur du matelas de gaz et commande alors l'ouverture d'une vanne particulière chargée d'assurer le complément de pression nécessaire au maintien de la hauteur souhaitée.Furthermore, there has been provided at the gas blowing point a kind of pocket placed on top of the piping and inside which a gas blanket is kept to prevent the entry of metal into the system. insufflation. This pocket is equipped with a probe which detects an abnormal reduction in the height of the gas mattress and then commands the opening of a special valve responsible for ensuring the additional pressure necessary to maintain the desired height.

L'établissement des différences de pression P₁ et P₂ convenable est obtenue à l'aide d'un manomètre différentiel commandé par un palpeur ou un détecteur de position quelconqueet qui agit sur l'ouverture ou la fermeture de vannes convenables.The establishment of suitable pressure differences P₁ and P₂ is obtained using a differential pressure gauge controlled by a feeler or any position detector and which acts on the opening or closing of suitable valves.

La valeur de P₂ doit être au moins égale à la valeur de la pression métallostatique exercée par le métal lorsqu'il remplit l'empreinte. Quant à la différence P₁ - P₂ elle est de l'ordre de 0,01 MPa.The value of P₂ must be at least equal to the value of the metallostatic pressure exerted by the metal when it fills the imprint. As for the difference P₁ - P₂ it is of the order of 0.01 MPa.

L'invention peut être illustrée à l'aide des dessins ci-joints qui représentent :

  • . Figure 1 : une vue en coupe verticale axiale d'une installation de moulage.
  • . Figure 2 : un schéma de l'installation de l'alimentation en gaz du récipient et de la tuyauterie.
The invention can be illustrated by means of the attached drawings which represent:
  • . Figure 1: a view in axial vertical section of a molding installation.
  • . Figure 2: a diagram of the installation of the gas supply to the container and the piping.

Sur la figure 1 on distingue le plateau inférieur 1 fixe et le plateau supérieur 2 mobile d'une machine verticale de moulage sous pression. Entre ces plateaux se trouve placé le moule 3 présentant une empreinte 4. Le plateau inférieur est équipé d'un dispositif d'injection constitué par le conteneur 5 dans lequel coulisse le piston 6 supporté par la tige 7 animée d'un mouvement de va et vient sous l'effet du vérin 18. Ledit conteneur est relié par l'intermédiaire de l'orifice 8 à la tuyauterie 9 qui plonge dans le bain 10 de métal à mouler contenu dans le creuset 11 placé dans le récipient 12 étanche qui peut être mis sous pression par l'intermédiaire de l'arrivée du gaz 13 afin d'envoyer le métal par la tuyauterie 9 vers le conteneur 5. Selon l'invention, on insuffle un gaz inerte dans la canalisation 14 en un point 15 de la tuyauterie 9 suivant une pression liée à la pression régnant dans le récipient en fonction de la position du piston détectée par le palpeur 17, pression qui peut être contrôlée par le manomètre différentiel régulateur 16.In FIG. 1, a distinction is made between the fixed lower plate 1 and the mobile upper plate 2 of a vertical die-casting machine. Between these plates is placed the mold 3 having an imprint 4. The lower plate is equipped with an injection device constituted by the container 5 in which the piston 6 slides, supported by the rod 7 which moves back and forth under the effect of the jack 18. Said container is connected via the orifice 8 to the piping 9 which plunges into the bath 10 of metal to be molded contained in the crucible 11 placed in the sealed container 12 which can be pressurized by means of the gas inlet 13 in order to send the metal through the piping 9 to the container 5. According to the invention, an inert gas is blown into the pipe 14 at a point 15 of the piping 9 according to a pressure linked to the pressure prevailing in the container as a function of the position of the piston detected by the probe 17, pressure which can be controlled by the differential pressure gauge 16.

Sur la figure 2 on retrouve les éléments de la figure 1 à savoir le conteneur 5, le piston 6, la tige 7, l'orifice 8, la tuyauterie 9, le bain de métal 10, le creuset 11, le récipient 12, l'arrivée de gaz 13, la canalisation 14, le point d'insufflation 15, le manomètre 16 et le palpeur 17.In Figure 2 we find the elements of Figure 1 namely the container 5, the piston 6, the rod 7, the orifice 8, the piping 9, the metal bath 10, the crucible 11, the container 12, l gas inlet 13, the pipe 14, the blowing point 15, the pressure gauge 16 and the probe 17.

A côté cde ces éléments, sont représentés tous ceux qui permettent de faire fonctionner l'installation. Ce sont, dans le sens de circulation des gaz :
- sur l'arrivée de gaz 13 :
. le détendeur haute pression 20
. le détendeur basse pression 21
. l'électrovanne 22 qui assure soit le passage du gaz vers le récipient, soit la mise à l'air du récipient
. le régleur de débit 23
. le clapet antiretour 24
- sur la canalisation 14 :
. le détendeur haute pression 25
. le détendeur basse pression 26
. l'électrovanne 27 à 2 voies
. l'électrovanne 28 à 3 voies dont l'une communique avec l'atmosphère. Ce couple de vannes permet de régler la pression P₁ dans la tuyauterie par rapport à la pression P2 dans le récipient par l'intermédiaire du manomètre différentiel 16.Next to these elements are shown all those which make it possible to operate the installation. These are, in the direction of gas flow:
- on gas supply 13:
. the high pressure regulator 20
. the low pressure regulator 21
. the solenoid valve 22 which ensures either the passage of the gas towards the container, or the venting of the container
. the flow regulator 23
. the non-return valve 24
- on line 14:
. the high pressure regulator 25
. the low pressure regulator 26
. 2-way solenoid valve 27
. 3-way solenoid valve 28, one of which communicates with the atmosphere. This pair of valves makes it possible to adjust the pressure P₁ in the piping relative to the pressure P2 in the container by means of the differential pressure gauge 16.

En effet, si P₁ est correct, ces deux vannes sont fermées, si P₁ est trop faible, la vanne 27 est ouverte et la mise à l'air de la vanne 28 est fermée; si P₁ est trop forte, la vanne 27 est fermée et la mise à l'air de la vanne 28 est ouverte.Indeed, if P₁ is correct, these two valves are closed, if P₁ is too low, the valve 27 is open and the venting of the valve 28 is closed; if P₁ is too strong, the valve 27 is closed and the venting of the valve 28 is open.

.l'électrovanne 29 dont l'ouverture permet un fort débit de gaz insufflé
. le régleur de débit 30
. le clapet antiretour 31
. le débitmètre 32
. l'électrovanne 33 qui assure l'arrêt ou le passage de gaz insufflé vers 15
. l'électrovanne 34 avec son régleur de débit 35 qui par suite d'une défaillance du circuit de gaz insufflé s'ouvre uniquement si la sonde 36 indique une montée de métal au niveau du point 15 et le risque d'un bouchage de la canalisation.the solenoid valve 29, the opening of which allows a high flow of blown gas
. the flow regulator 30
. the non-return valve 31
. the flow meter 32
. the solenoid valve 33 which stops or passes the gas supplied to 15
. the solenoid valve 34 with its flow regulator 35 which due to a failure of the blown gas circuit opens only if the probe 36 indicates a rise in metal at point 15 and the risk of blockage of the pipe .

Au cours d'un cycle de moulage, l'installation fonctionne de la façon suivante :

  • 1. Le moule étant ouvert pour extraire la pièce, le récipient est à la pression atmosphèrique par l'intermédiaire de la vanne 22, le piston en position basse, la vanne 29 fermée, le manomètre différentiel 16 sur la position P₁ > P₂ de sorte qu'un faible débit de gaz arrive en 15 par l'intermédiaire du régleur de débit 30 et de la vanne 33.
  • 2. Le moule est refermé, prêt pour une nouvelle injection. La situation des éléments précédents reste identique de sorte que le gaz balaye l'empreinte et en chasse l'air.
  • 3. L'ordre d'injection étant donné, la vanne 33 se ferme isolant la chambre 15, ce qui annule la condition P1 > P2 tandis que la vanne 29 s'ouvre. La vanne 22 assure le passage du gaz vers le récipient et provoque la montée de métal liquide vers le conteneur. Lorsque le piston commence son ascension la vanne 29 étant ouverte est prête à assurer la pression de gaz P₁ > P₂ suffisante pour empêcher l'introduction de métal dans le circuit d'insufflation de gaz par formation d'un matelas protecteur au point 15.
  • 4. Dès que le piston obture l'orifice 8, la vanne 33 est ouverte de sorte que P₁ devienne supérieure à P₂ et accélère le retour de métal vers le récipient pour éviter tout épanchement de métal dans le cylindre au moment où la tige de piston apparaît au niveau de l'orifice 8 et toute entrée d'air provenant dudit cylindre.
  • 5. Le piston continue sa progression vers le haut pendant la solidification de la pièce tandis que la vanne 22 est mise à l'air pour faire chuter P₂. P₁ est modulée sur P₂ de manière à avoir constamment P₁ > P₂.
  • 6. Les vannes restant dans la même position, le moule est ouvert et le piston dans son mouvement ascendant chasse la pastille d'injection.
  • 7. Le piston revient à la position basse. Au moment où il démasque l'orifice 8, la vanne 29 se ferme de sorte qu'une légère pression de gaz est assurée par le régleur 30 afin de purger le conteneur.
During a molding cycle, the installation operates as follows:
  • 1. The mold being opened to extract the part, the container is at atmospheric pressure via the valve 22, the piston in the low position, the valve 29 closed, the differential pressure gauge 16 in the position P₁> P₂ so that a low gas flow arrives at 15 via the flow regulator 30 and the valve 33.
  • 2. The mold is closed, ready for a new injection. The situation of the preceding elements remains identical so that the gas sweeps the footprint and expels the air.
  • 3. The injection order being given, the valve 33 closes isolating the chamber 15, which cancels the condition P1> P2 while the valve 29 opens. The valve 22 ensures the passage of the gas towards the container and causes the rise of liquid metal towards the container. When the piston begins its ascent the valve 29 being open is ready to ensure the gas pressure P₁> P₂ sufficient to prevent the introduction of metal into the gas insufflation circuit by the formation of a protective mattress at point 15.
  • 4. As soon as the piston closes the orifice 8, the valve 33 is opened so that P₁ becomes greater than P₂ and accelerates the return of metal to the container to avoid any effusion of metal in the cylinder when the piston rod appears at the orifice 8 and any entry of air from said cylinder.
  • 5. The piston continues its upward progression during the solidification of the part while the valve 22 is vented to cause P₂ to fall. P₁ is modulated on P₂ so as to have constantly P₁> P₂.
  • 6. The valves remaining in the same position, the mold is opened and the piston in its upward movement drives out the injection tablet.
  • 7. The piston returns to the low position. When it unmasks the orifice 8, the valve 29 closes so that a slight gas pressure is ensured by the regulator 30 in order to purge the container.

Le cycle de moulage est alors redémarré.The molding cycle is then restarted.

Il est clair que toutes ces opérations sont rendues automatiques en utilisant des appareils de régulation et de contrôle bien connus de l'homme de l'art.It is clear that all these operations are made automatic using regulation and control devices well known to those skilled in the art.

Claims (4)

1. Machine de moulage sous pression à chambre froide pour la fabrication de pièces métalliques contenant éventuellement des fibres en céramiques formée d'un plateau inférieur (1) fixe et d'un plateau supérieur (2) mobile entre lesquels est placé un moule (3) présentant une empreinte (4) de la pièce à mouler, ledit plateau inférieur étant équipé d'un dispositif d'injection constitué par un conteneur (5) dans lequel coulisse un piston (6) supporté par une tige (7), ledit conteneur étant relié par l'orifice (8) à une tuyauterie (9) qui plonge dans un bain (10) liquide du métal à mouler contenu dans un récipient (12) étanche, ledit récipient pouvant être mis sous une pression P2 par l'intermédiaire d'une arrivée de gaz (13) afin d'envoyer le métal vers le conteneur, caractérisée en ce que dans le but d'éviter tout épanchement de métal liquide sur la tige du piston et toute entrée d'air dans la tuyauterie (9), ladite tuyauterie est équipée en un point (15) de sa paroi voisin du conteneur (5) d'une alimentation en gaz inerte (14) et d'une poche sous pression P1 dépendant de la position du piston (6) et de P2.1. Cold chamber pressure molding machine for manufacturing metal parts possibly containing ceramic fibers formed by a fixed lower plate (1) and a movable upper plate (2) between which a mold (3) is placed ) having an imprint (4) of the part to be molded, said lower plate being equipped with an injection device constituted by a container (5) in which slides a piston (6) supported by a rod (7), said container being connected by the orifice (8) to a pipe (9) which plunges into a liquid bath (10) of the metal to be molded contained in a sealed container (12), said container being able to be put under pressure P2 via a gas inlet (13) in order to send the metal to the container, characterized in that in order to avoid any effusion of liquid metal on the piston rod and any entry of air into the piping (9 ), said piping is equipped at a point (15) on its wall close to the container (5 ) an inert gas supply (14) and a pressure bag P1 depending on the position of the piston (6) and P2. 2. Machine selon la revendication 1, caractérisée en ce que P₂ étant supérieur à P₁ durant la période d'alimentation en métal du conteneur et de l'empreinte, P₁ devient supérieur à P₂ à l'instant où le piston dans son mouvement ascendant masque l'orifice (8).2. Machine according to claim 1, characterized in that P₂ being greater than P₁ during the metal supply period of the container and of the imprint, P₁ becomes greater than P₂ at the moment when the piston in its upward movement masks the orifice (8). 3. Machine selon la revendication 1 caractérisée en ce que la valeur de P₁ est réduite à l'instant où le piston dans son mouvement descendant démasque l'ouverture (8) et ce jusqu'à ce que P₂ augmente.3. Machine according to claim 1 characterized in that the value of P₁ is reduced at the time when the piston in its downward movement unmasks the opening (8) and this until P₂ increases. 4. Machine selon la revendication 1 caractérisée en ce que les différences de pression P1 et P2 sont obtenues à l'aide d'un manomètre différentiel (16) commandé par un palpeur (17).4. Machine according to claim 1 characterized in that the pressure differences P1 and P2 are obtained using a differential pressure gauge (16) controlled by a probe (17).
EP87420297A 1986-10-31 1987-10-30 Pressure die casting machine for metallic articles which may contain ceramic fibres Expired EP0270466B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87420297T ATE46640T1 (en) 1986-10-31 1987-10-30 DIE CASTING MACHINE FOR METAL CASTINGS THAT MAY CONTAIN CERAMIC FIBERS.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8615437A FR2605913A1 (en) 1986-10-31 1986-10-31 METHOD FOR PRESSURIZED MOLDING OF METALLIC PARTS CONTAINING CERAMIC FIBERS
FR8615437 1986-10-31

Publications (2)

Publication Number Publication Date
EP0270466A1 true EP0270466A1 (en) 1988-06-08
EP0270466B1 EP0270466B1 (en) 1989-09-27

Family

ID=9340563

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87420297A Expired EP0270466B1 (en) 1986-10-31 1987-10-30 Pressure die casting machine for metallic articles which may contain ceramic fibres

Country Status (21)

Country Link
US (1) US4777998A (en)
EP (1) EP0270466B1 (en)
JP (1) JPS63115664A (en)
KR (1) KR910009368B1 (en)
AR (1) AR241762A1 (en)
AT (1) ATE46640T1 (en)
AU (1) AU586786B2 (en)
BR (1) BR8705803A (en)
CA (1) CA1302045C (en)
DE (1) DE3760607D1 (en)
DK (1) DK160467C (en)
ES (1) ES2010716B3 (en)
FI (1) FI82620C (en)
FR (1) FR2605913A1 (en)
GR (1) GR3000173T3 (en)
IE (1) IE62774B1 (en)
IS (1) IS1397B6 (en)
MX (1) MX169523B (en)
NO (1) NO167635C (en)
PT (1) PT86026B (en)
SU (1) SU1637659A3 (en)

Cited By (3)

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Publication number Priority date Publication date Assignee Title
EP0379420A1 (en) * 1989-01-16 1990-07-25 Creusot-Loire Industrie Device and method for feeding with molten metal for pressure die casting metallic products
DE10061026A1 (en) * 2000-12-08 2002-06-13 Bayerische Motoren Werke Ag Metal casting process and device
CN108994278A (en) * 2018-09-19 2018-12-14 深圳市乐业科技有限公司 A kind of compression casting equipment of quantitative accurate

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US5085830A (en) * 1989-03-24 1992-02-04 Comalco Aluminum Limited Process for making aluminum-lithium alloys of high toughness
US5570502A (en) * 1991-04-08 1996-11-05 Aluminum Company Of America Fabricating metal matrix composites containing electrical insulators
US5616421A (en) * 1991-04-08 1997-04-01 Aluminum Company Of America Metal matrix composites containing electrical insulators
US5259436A (en) * 1991-04-08 1993-11-09 Aluminum Company Of America Fabrication of metal matrix composites by vacuum die casting
US5775403A (en) * 1991-04-08 1998-07-07 Aluminum Company Of America Incorporating partially sintered preforms in metal matrix composites
JPH0623510A (en) * 1992-05-26 1994-02-01 Tanabe Kogyo Kk Method and device for supplying air and molten metal in inert gas and molten metal supplying pipe and inert gas concentrated atmosphere trough and inert gas atmosphere box
US5533257A (en) * 1994-05-24 1996-07-09 Motorola, Inc. Method for forming a heat dissipation apparatus
DK77694A (en) * 1994-06-29 1995-12-30 Dansk Ind Syndikat Method and device for casting against the gravity of molds, especially wet sand molds, in particular easily oxidizable metals or metal alloys of the finished molding process
EP1035932A1 (en) * 1997-11-07 2000-09-20 AB Jafs Export Oy Holimesy Method and apparatus for melting non-ferrous metals, especially magnesium
DE19802342C1 (en) * 1998-01-22 1999-03-04 Gustav Ohnsmann Apparatus for supplying horizontal and vertical cold chamber diecasting machines with metal
DE19812068C2 (en) * 1998-03-11 2000-09-21 Gut Gieserei Umwelt Technik Gm Pouring device with post-compaction
DE19943153C1 (en) * 1998-03-19 2001-01-25 Gut Gieserei Umwelt Technik Gm Apparatus for vacuum or pressure casting workpieces comprises a closing device and a pressure producing device formed as a one-piece piston arranged above a riser pipe
US20090160106A1 (en) * 2004-10-12 2009-06-25 Efficient Manufacturing System Integration Apparatus and method for simultaneous usage of multiple die casting tools
CN104985159B (en) * 2015-07-03 2017-06-13 洛阳西格马炉业股份有限公司 A kind of die casting equipment and method for producing refractory metal coating ceramic chip material
CN106694838B (en) * 2016-11-10 2018-07-03 重庆代发铸造有限公司 Anti-bubble casting device

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US3058179A (en) * 1959-04-20 1962-10-16 Cannon Earl Die casting machine
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EP0017331A1 (en) * 1979-03-21 1980-10-15 Promagco Limited Improvements relating to hot chamber die-casting

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US3058179A (en) * 1959-04-20 1962-10-16 Cannon Earl Die casting machine
DE1458062A1 (en) * 1964-11-23 1969-03-20 Goehring Dipl Ing Karl Loading device for casting machines
EP0017331A1 (en) * 1979-03-21 1980-10-15 Promagco Limited Improvements relating to hot chamber die-casting

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0379420A1 (en) * 1989-01-16 1990-07-25 Creusot-Loire Industrie Device and method for feeding with molten metal for pressure die casting metallic products
WO1990008002A1 (en) * 1989-01-16 1990-07-26 Creusot Loire Industrie Device and process for introducing liquid metal during under pressure casting of metallic products
FR2642686A1 (en) * 1989-01-16 1990-08-10 Creusot Loire DEVICE AND METHOD FOR FEEDING LIQUID METAL FOR PRESSURE-COUPLED METAL PRODUCTS
US5180538A (en) * 1989-01-16 1993-01-19 Creusot-Loire Industrie Device and method for feeding molten metal for the pressure casting of metal products
DE10061026A1 (en) * 2000-12-08 2002-06-13 Bayerische Motoren Werke Ag Metal casting process and device
CN108994278A (en) * 2018-09-19 2018-12-14 深圳市乐业科技有限公司 A kind of compression casting equipment of quantitative accurate
CN108994278B (en) * 2018-09-19 2020-05-12 新成业机铸制品(深圳)有限公司 Accurate pressure casting equipment of ration

Also Published As

Publication number Publication date
DK160467C (en) 1991-09-30
MX169523B (en) 1993-07-09
FR2605913A1 (en) 1988-05-06
BR8705803A (en) 1988-05-31
PT86026B (en) 1993-08-31
DK566687D0 (en) 1987-10-29
DK160467B (en) 1991-03-18
ATE46640T1 (en) 1989-10-15
CA1302045C (en) 1992-06-02
FI874796A0 (en) 1987-10-30
JPH0230789B2 (en) 1990-07-09
NO167635C (en) 1991-11-27
NO874507L (en) 1988-05-02
NO874507D0 (en) 1987-10-29
KR880004876A (en) 1988-06-27
DK566687A (en) 1988-05-01
FI82620C (en) 1991-04-10
AU586786B2 (en) 1989-07-20
EP0270466B1 (en) 1989-09-27
US4777998A (en) 1988-10-18
FI874796A (en) 1988-05-01
IE62774B1 (en) 1995-02-22
ES2010716B3 (en) 1989-12-01
AU8045687A (en) 1988-05-05
KR910009368B1 (en) 1991-11-14
IE872921L (en) 1988-04-30
SU1637659A3 (en) 1991-03-23
GR3000173T3 (en) 1990-12-31
PT86026A (en) 1988-11-30
DE3760607D1 (en) 1989-11-02
FI82620B (en) 1990-12-31
JPS63115664A (en) 1988-05-20
IS3275A7 (en) 1988-05-02
AR241762A1 (en) 1992-12-30
NO167635B (en) 1991-08-19
IS1397B6 (en) 1989-10-31

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