CH271173A

CH271173A - Device for separating a mold from the model used in its manufacture.

Info

Publication number: CH271173A
Authority: CH
Inventors: Company Herman Pneumat Machine
Original assignee: Herman Pneumatic Machine Co
Priority date: 1946-06-14
Filing date: 1947-06-13
Publication date: 1950-10-15

Description

Dispositif pour separer un moule du modele ayant servi ä sa fabrieation. La presente invention se rapporte ä un dispositif pour separer un moule du modele ayant servi ä sa fabrication. Device for separating a mold from the model used in its manufacture. The present invention relates to a device for separating a mold from the model having served for its manufacture.

Le dessin ei-annexe montre, ä titre d'exemple, une forme d'execution de 1'objet de 1'invention. The appended drawing shows, by way of example, one form of execution of the object of the invention.

La fig.l montre, en coupe verticale schematique, un mecanisme ä demouler lös moules ainsi que lös conduits pour la distri- bution des fluides pour son fonctionnement. FIG. 1 shows, in schematic vertical section, a mechanism for demoulding the molds as well as the ducts for the distribution of the fluids for its operation.

Les fig. 2, 3 montrent respectivement en elevation (parties en coupe) et en plan, 1e meme mecanisme. Figs. 2, 3 respectively show in elevation (parts in section) and in plan, the same mechanism.

La fig. 4 montre, en vue de cöte, depuis la drohe et ä plus petite khelle, 1e m6ca- nisme demouleur des fig. 2 et 3. fig. 4 shows, in side view, from the right and at a smaller scale, the mold release mechanism of FIGS. 2 and 3.

La fig.5 montre, semblablement, une partie detaillee du mecanisme montre Sur la fig. 2. Fig.5 similarly shows a detailed part of the mechanism shown in fig. 2.

Sur lös dessins an a designe par 2 1e Sup port pour un modele et un moule et qui peut faire partie du dispositif servant au tasse- ment du materiel destine ä constituer 1e moule. In the drawings, a has been designated by 2 as the support for a model and a mold and which may be part of the device used to compact the material intended to constitute the mold.

L'ensernble constitue par 1e modele et 1e moule est pose Sur 1e Support 2. Pour separer ces deux elements 1'un de 1'autre, 1'un d'eux est maintenu en place Sur ledit Support 2 pendant que 1'autre est deplace verticale- ment et en ligne droite pour 1'karter du premier. Le moule est generalement forme Jans un chässis dans lequel 1e materiel qui doit 1e constituer, par exemple 1e sable, est tasse au contact du modele. Si 1e chässis est ouvert vers 1e haut, 1e modele peut etre karte du moule pendant que ce dernier est maintenu Sur 1e Support 2. Si 1e chässis est ouvert vers 1e bas, 1e modele peut etre main- tenu en place Sur 1e Support et 1e chässis peut eire deplace vers 1e haut pour karier 1e moule de son modele. The assembly constituted by the first model and the first mold is placed on the first support 2. To separate these two elements from each other, one of them is held in place on said support 2 while the other is moves vertically and in a straight line for the karter of the first. The mold is generally formed in a frame in which the material which is to constitute it, for example sand, is compacted in contact with the model. If the frame is open upwards, the model can be held in place on the mold while the latter is held on the Support 2. If the frame is open downwards, the model can be held in place On the Support and the frame can be moved upwards to change the mold of its model.

Le soulevement du moule ou du modele est effectue par lös bras 3, par exemple au nombre de quatre. Chaque bras est monte Sur une des deux tetes opposees 4 et 5, etablies de pari et d'autre du mecanisme. Deux bras sont relies ä chaque töte et partent de celle-ei dann 1e sens longitudinal, lös bras relies ä la töte 4 kant orientes vers lös bras solidaires de la töte 5 et vice versa (fig. 3). Chaque bras est reue, dune maniere reglable, ä la töte, afin qu'il puisse s'etendre, Sur la longueur voulue, ä partir de celle-ei. Dans 1'extremite libre de chaque bras est engagee une vis 6 propre ä eire maintenue dann une position ajustee par un ecrou 7. Les vis 6 RTI ID="0001.0272" WI="7" HE="4" LX="1057" LY="1959"> sont reglees de maniere teile que lös faces superieures des tetes des quatre vis se trou- vent au meme niveau. Quand lös quatre bras 3 sont souleves simultanement, lös faces superieures des tetes des vis 6 viennent simul- tan6ment en contact avec 1e chässis ou 1e modele, suivant 1e cas, pour faire monter celui-ei et 1'ecarter de 1'autre. Dans 1e Support 2 sont menagees des fentes dans lesquelles passent les bras 3. Quand les tetes 4 et 5 sont ä leur Position hasse, les bras 3 et les vis 6 sont engages dans les fentes 8 en dessous de la face superieure du Support 2. De cette maniere, an peut placer 1e moule et 1e modele Sur 1e Support 2 sans qu'ils viennent en con- tact avec les bras et quand 1e demoulage doit avoir lieu, les moules sont deplaces vers 1e haut pour venir en contact et soulever 1e moule ou 1e modele qui se trouve au-dessus. The raising of the mold or the model is carried out by the arm 3, for example four in number. Each arm is mounted on one of the two opposite heads 4 and 5, established on either side of the mechanism. Two arms are connected to each head and depart from the latter in the longitudinal direction, the arms connected to the head 4 being oriented towards the arms integral with the head 5 and vice versa (FIG. 3). Each arm is received, in an adjustable way, at the head, so that it can extend, on the desired length, from this one. In the free end of each arm is engaged a screw 6 suitable for eire held in a position adjusted by a nut 7. The screws 6 RTI ID="0001.0272" WI="7" HE="4" LX="1057" LY="1959"> are adjusted so that the upper faces of the heads of the four screws are at the same level. When the four arms 3 are raised simultaneously, the upper faces of the heads of the screws 6 come simultaneously into contact with the frame or the model, as the case may be, to raise the latter and move it away from the other. In the Support 2 there are slots through which the arms 3 pass. When the heads 4 and 5 are in their up position, the arms 3 and the screws 6 are engaged in the slots 8 below the upper face of the Support 2. In this way, the mold and the model can be placed on the Support 2 without them coming into contact with the arms and when demolding is to take place, the molds are moved upwards to come into contact and lift the mold or the first model which is above.

La tete 4 est formee par 1'extremite supe- rieure, de section plus Brande, d'un piston creux 9 qui peut travailler dans un cylindre vertical 10 qui est monte, en tandem, au- dessus d'un cylindre 11 de section transver- sale plus Brande. Bien que les cylindres 10 et 11 soient constitues par des pieces coulees separees, ils forment, en realite, un seul en- semble. L'extremite inferieure du piston creux 9 est engagee dans 1e Brand cylindre 11 et forme un prolongement, oriente v ers 1e bas, du piston creux. Ce prolongement Porte, ä son extremite inferieiue, un piston 12 tra- vaillant dans 1e cylindre 11. La paroi supe- rieure de la tete 4 est fermee de maniere ä etre etanche ä Fair et au gaz. The head 4 is formed by the upper end, of larger section, of a hollow piston 9 which can work in a vertical cylinder 10 which is mounted, in tandem, above a cylinder 11 of cross section. - dirty more Brande. Although the cylinders 10 and 11 are made up of separate castings, they actually form a single assembly. The lower end of the hollow piston 9 is engaged in the first Brand cylinder 11 and forms an extension, oriented towards the first bottom, of the hollow piston. This extension carries, at its lower end, a piston 12 working in the cylinder 11. The upper wall of the head 4 is closed so as to be airtight and gastight.

Dans 1e piston 12 ou dans 1e fond du piston creux 9 est menagee une ouverture circulaire centrale 13. Sur 1e fond du cylindre 11 est monte un organe regulateur de vitesse 14, engage en etant oriente vers 1e haut dans Fouverture 13, cet organe etant cons- titu6 par une tige de section transversale circulaire mais non uniforme. La Partie cylindrique inferieure 15 a un diamUre maximum et ce diametre est legerement inferieur ä celiü de Fouverture 13, de Sorte qu'un Passage annulaire subsiste constam- ment entre Forgane regulateur de vitesse et 1e bord de cette ouverture. Dans 1e fond du cyhndre 11 sont menagees une ou plusieurs encoches ou rainures 16 qiü communiquent avec Fouverture 13 tout en etant ouvertes du cöte du fond de Fensemble des pistons 9 et 12, de Sorte que, lorsque du liquide est refoule vers 1e bas ä travers 1'ouverture 13, comme decrit ei-apres, an obtient 1e deplacement dudit ensemble vers 1e haut. L'organe regulateur de vitesse 14 com- porte, ä son extremite superieure, une Partie cylindrique 17 dont 1e diametre est egal ä celui de la Partie 15. Entre ces Parties cylin- driques 15 et 17 sont prevues deux Parties tronconiques 18 et 19 entre lesquelles se trouve RTIID="0002.0278" WI="6" HE="4" LX="1254" LY="504"> une Partie cylindrique 20, de diamUre minimum. La Partie tronconique inferieure 18 permet de passer graduellement du dia- metre de la Partie cylindrique inferieure 15 ä celui de la Partie intermediair e 20 et la Partie tronconique superieure 19 reue pro- gressivement cette Partie intermediaire 20 ä la Partie superieure 17 de Brand diamUre. Un collet 21 entoure Forgane regulateur 14 et cet organe est applique normalement Sur la face interne du fond du piston creux 9 et coaxialement par rapport ä 1'ouverture 13. Le diamUre interne du collet 21 est legere ment plus Brand que 1e diametre externe des Parties 15 et 17 de Forgane regulateur 14 et il en resulte que, lorsque 1e collet 21 est applique Sur 1e fond du piston creux 9 et lorsque les organes occupent leur Position montree Sur les fig. 1 et 2, un Passage tres restreint soit forme entre 1e collet 21 et Forgane regulateur 14. Dans certaines con-ditions, indiquees ei-apres, 1e collet 21 est karte de son siege Sur 1e fond du piston creux 9 et quand ceci se presente un Passage de section transversale relativement Brande est forme immediatement entre 1'interieur i du piston creux et les encoches 16. Quand 1e collet 21 occupe sa Position inactive la sec- tion transversale du Passage est determinee par la paroi de Fouverture 13 et par la face externe de 1'organe regulateur 14. , Le cylindre 11 est monte Sur une Plaque 22, faisant Partie du bäti, ä 1'aide de boulons 23. Le cylindre 10 est reue convenablement au cylindre 11, de Sorte que les deux cylindres forment un ensemble integral, comme dejä dit. La Plaque 22 Porte egalement, ä Faide de boulons 24, un cylindre 25 de diametre relativement Brand et Sur lequel est monte un cylindre 26 de diamUre plus Petit. Dans 1e cylindre 26 travaille un piston creux 27 s dont la Partie superieure est constituee par la tete 5 qui, de meme que la täte 4, est fermee ä sa partie superieure de maniere ä etre Uanche ä Fair et au gaz. Le fond du pis- ton creux 27 est forme par un bouchon 28. In the piston 12 or in the bottom of the hollow piston 9 is formed a central circular opening 13. On the bottom of the cylinder 11 is mounted a speed regulating member 14, engaged while being oriented upwards in the opening 13, this member being formed - titu6 by a rod of circular cross-section but not uniform. The lower cylindrical part 15 has a maximum diameter and this diameter is slightly less than that of the opening 13, so that an annular passage constantly remains between the speed regulator member and the edge of this opening. In the bottom of the cylinder 11 are formed one or more notches or grooves 16 which communicate with the opening 13 while being open on the side of the bottom of the set of pistons 9 and 12, so that when liquid is forced downwards through the opening 13, as described below, obtains the first displacement of said assembly upwards. The speed regulator member 14 comprises, at its upper end, a cylindrical part 17 whose diameter is equal to that of the part 15. Between these cylindrical parts 15 and 17 are provided two tapered parts 18 and 19 between which is RTIID="0002.0278" WI="6" HE="4" LX="1254" LY="504"> a cylindrical part 20, of minimum diameter. The lower frustoconical part 18 makes it possible to pass gradually from the diameter of the lower cylindrical part 15 to that of the intermediate part 20 and the upper frustoconical part 19 gradually receives this intermediate part 20 to the upper part 17 of Brand diameter. A collar 21 surrounds the regulating member 14 and this member is applied normally to the internal face of the bottom of the hollow piston 9 and coaxially with respect to the opening 13. The internal diameter of the collar 21 is slightly larger than the external diameter of the parts. 15 and 17 of the regulator organ 14 and it follows that, when the first collar 21 is applied to the first bottom of the hollow piston 9 and when the organs occupy their position shown in FIGS. 1 and 2, a very restricted passage is formed between the first collar 21 and the regulating organ 14. a Passage of relatively wide cross section is formed immediately between the interior of the hollow piston and the notches 16. When the collar 21 is in its inactive position the cross section of the Passage is determined by the wall of the opening 13 and cylinder 11 is mounted on plate 22, forming part of the frame, by means of bolts 23. Cylinder 10 is properly received by cylinder 11, so that the two cylinders integral set, as already said. Plate 22 also carries, by means of bolts 24, a cylinder 25 of relatively large diameter and on which is mounted a cylinder 26 of smaller diameter. In the cylinder 26 works a hollow piston 27, the upper part of which is formed by the head 5 which, like the head 4, is closed at its upper part so as to be sealed with air and gas. The bottom of the hollow piston 27 is formed by a plug 28.

Un conduit 29 part d'un raccord 30, en forme de T, et aboutit dans 1e cylindre 25. Le raccord est relie, d'autre part, par un conduit 31 avec Fespace annulaire compris entre 1e cylindre 11 et 1e piston creux 9. Le raccord 30 est egalement reue, par un conduit 33, ä une soupape 34 qui, ä son tour, communique par un conduit 35 avec 1'inte- rieur du cylindre 11, par 1e fond de celui-ei et en dessous du piston 12. Comme il Sera explique ei-apres, la soupape 34 peut etre ouverte pour etablir la communication entre 1e conduit 33 et 1e conduit 35 et elle peut etre fermde pour interrompre cette commu- nication. A duct 29 starts from a T-shaped connector 30 and ends in the cylinder 25. The connector is connected, on the other hand, by a duct 31 with the annular space between the cylinder 11 and the hollow piston 9. Connector 30 is also received, through conduit 33, at valve 34 which, in turn, communicates through conduit 35 with the interior of cylinder 11, through the bottom thereof and below piston 12. As will be explained below, valve 34 can be opened to establish communication between conduit 33 and conduit 35 and can be closed to interrupt such communication.

11 est prevu une source de gaz sous pres- sion, par exemple et de preference de Fair comprime, cette source pouvant etre cons- titu6e par un compresseur d'air approprie. L'air comprime est debite par 1e compresseur dann 1e conduit 36 aboutissant ä un distribu- teur 37 d'oü Part un conduit 38 relie, par un raccord flexible 39,ä un conduit qui d6bou- che, en 40, dans la partie superieure de la cavite de la tete 4. Un autre conduit 41 Part du distributeur 37 et aboutit ä la soupape 34 pour fournir de Fair comprime ä celle-ei, pour la faire fonctionner. Si an 1e desire, la soupape 34 est normalement ou- verte, par exemple ä Faide d'un ressort, pour dtablir la communication entre 1e conduit 33 et 1e conduit 35 et eile peut eire fermee quand de Fair comprime est fourni au con- duit 41 par 1e distributeur 37 qui comporte une manette de commande 42. Le distribu- teur 37 peut occuper une premiere position caracteristique pour laquelle Fair comprime ne peut pas penetrer dans les conduits 38 et 41, ceux-ei etant alors relies ä un conduit d'dchappement 43, une deuxieme position pour laquelle Fair comprime est seulement admis dans 1e conduit 41 pour fermer 1.a soupape 34 et une troisieme Position pour laquelle Pair comprime est admis ä la fois dans les conduits 41 et 38. Provision is made for a source of pressurized gas, for example and preferably of compressed air, this source possibly consisting of a suitable air compressor. The compressed air is delivered by the compressor in the conduit 36 leading to a distributor 37 from which a conduit 38 is connected, by a flexible connector 39, to a conduit which emerges, at 40, in the upper part. from head cavity 4. Another conduit 41 extends from distributor 37 to valve 34 to supply compressed air thereto for operation. If desired, valve 34 is normally open, for example by means of a spring, to establish communication between conduit 33 and conduit 35 and may be closed when compressed air is supplied to the conduit. 41 by the distributor 37 which comprises a control lever 42. The distributor 37 can occupy a first characteristic position for which the compressed air cannot enter the ducts 38 and 41, these then being connected to a duct of exhaust 43, a second position in which compressed air is only admitted to conduit 41 to close valve 34 and a third position in which compressed air is admitted to both conduits 41 and 38.

L'espace annulaire 32, compris entre 1e piston creux 9 et 1e cylindre 11,a une section transversale sensiblement egale ä la section transversale du cylindre 26. The annular space 32, comprised between the hollow piston 9 and the cylinder 11, has a cross section substantially equal to the cross section of the cylinder 26.

Le dispositif ainsi constitue fonctionne comme suit : Quand un moule doit etre ecarte du modele ou vice versa, les bras 3 sont, au debut, engages dans les RTI ID="0003.0277" WI="10" HE="4" LX="1463" LY="596"> fentes 8, et ]es pis- tons 9 et 12 sont au bas de leurs courses respectives (fig. 1 et 2). Le piston creux 9 est rempli avec un fluide, de preference un fluide non compressible tel que 1'huile, jus- qu'ä un niveau legerement en dessous du debouche 40 du conduit 38-39. L'ouverture 13, les encoches 16 et 1e conduit 33 sont rem- plis avec 1e meme fluide. Le fluide, contenu dann 1e piston creux 9, ne doit pas n6cessaire- ment etre non compressible et an peut egale- ment se servir d'un gaz tel que de Fair. L'es- pace annulaire 32, les conduits 31, 33 et 29, 1e raccord 30 en<B>T</B> et Fespace annulaire entre 1e piston 27 et 1e cylindre 25 sont egalement remplis avec un fluide qui, pour obtenir un fonctionnement exact, doit eire un fluide non compressible, tel que de 1'huile par exem- ple. Quand an se sert Tun fluide non com- pressible dans 1e piston creux 9, ce fluide est de preference 1e meme que celui qui sert ä actionner 1e piston, car, lors de Fouverture de la soupape 34, les deux fluides sont melanges. Si Von se sert de fluides differents dann 1e piston creux 9 et pour actionner 1e piston 27, plus specialement quand un gaz se trouve Jans 1e piston 9, la soupape 34 et les conduits 33 et 35 n'ont plus aucune utilite et peuvent etre supprimes. Pour 1'exemple montre, an admet que la meme huile est utilisde ä la fois dann 1e piston creux 9 et pour actionner 1e piston 27. The device thus constituted operates as follows: When a mold must be removed from the model or vice versa, the arms 3 are, at the start, engaged in the RTI ID="0003.0277" WI="10" HE="4" LX=" 1463" LY="596"> slots 8, and] the pistons 9 and 12 are at the bottom of their respective races (fig. 1 and 2). Hollow piston 9 is filled with a fluid, preferably a non-compressible fluid such as oil, to a level slightly below outlet 40 of conduit 38-39. Aperture 13, notches 16 and conduit 33 are filled with the same fluid. The fluid contained in the hollow piston 9 need not be non-compressible and a gas such as air can also be used. The annular space 32, the conduits 31, 33 and 29, the <B>T</B> fitting 30 and the annular space between the piston 27 and the cylinder 25 are also filled with a fluid which, in order to obtain a exact operation, must be a non-compressible fluid, such as oil for example. When a non-compressible fluid is used in the hollow piston 9, this fluid is preferably the same as that used to actuate the piston, because, when the valve 34 is opened, the two fluids are mixed. If different fluids are used in hollow piston 9 and to actuate piston 27, especially when gas is present in piston 9, valve 34 and conduits 33 and 35 no longer serve any purpose and can be removed. . For the example shown, it is assumed that the same oil is used both in the hollow piston 9 and to actuate the piston 27.

Le distributeur 37 occupe, au debut, une position pour laquelle les conduits 38 et 41 sont relies ä 1'echappement et la soupape 34 est, au debut, ouverte pour etablir la com- munication entre les conduits 33 et 35. Quand les organes occupent cette position, tous les conduits, cavites et espaces, dont il est question plus haut, sont remplis avec de l'huile fournie par la reserve qui est con- tenue dans 1e piston creux 9. Distributor 37 initially occupies a position in which conduits 38 and 41 are connected to the exhaust and valve 34 is initially open to establish communication between conduits 33 and 35. In this position, all the ducts, cavities and spaces, mentioned above, are filled with oil supplied by the reserve which is contained in the hollow piston 9.

Avant 1e demoulage, 1e distributeur est amene ä la Position pour laquelle de Fair comprime est admis seulement dans 1e con- duit 41 pour fermer la soupape 34 et inter- rompre la communication entre les conduits 33 et 35. Lorsque la soupape 34 est fermee et en admettant que l'huile soit incompres- sible, tont mouvement vers 1e haut du piston 9 est accompagne dune montee analogue du piston 27 puisque la section transversale de Fespace annulaire 32 est, en substance, egale ä la section utile du piston 27, comme expli- qu6 plus haut. Ceci est egalement 1e cas quand 1e fluide, contenu dann 1e piston creux 9, est un gaz. Prior to demolding, the distributor is moved to the position at which compressed air is admitted only into conduit 41 to close valve 34 and interrupt communication between conduits 33 and 35. When valve 34 is closed and assuming the oil to be incompressible, any upward movement of piston 9 is accompanied by a similar upward movement of piston 27 since the cross-section of annular space 32 is substantially equal to the useful cross-section of piston 27, as explained above. This is also the case when the fluid contained in the hollow piston 9 is a gas.

Le distributeur est ensuite amene ä la Position pour laquelle de Fair comprime est maintenu dann 1e conduit 41 et est admis egalement dans 1e conduit 38. L'air com- prime, qui traverse 1e conduit 38 et 1e raccord flexible 39, penetre Jans la tete 4 par 1e debouche 40 oü cet air vieret agir entre l'huile contenue dans 1e piston 9 et la paroi superieure de la tete. Comme celle-ci est Manche ä fair, la Pression est exercee Sur l'huile qui est refoulee vers 1e bas dans Finter- valle cömpris entre la Partie 15 de Porgane regulateur de vitesse 14 et 1e collet 21 et, de 1ä, par Fouverture 13 jusque dans les encoches 16 menagees dann 1e fond du cy- lindre 11 pour refouler les pistons 12 et 9 vers 1e haut. Pendant la montee des pistons 12 et 9, 1e collet 21 reste applique Sur son siege prevu Sur la face interne du fond du piston 9 (fig. 2), de Sorte que 1e debit effectif de 1'huile, depuis 1'interieur du piston 9 jusque dans 1'espace en dessous des pistons et dann 1e cylindre 11, est determine par 1e collet 21 et Forgane regulateur de vitesse 14. Pendant que 1e piston 9 monte, 1e collet 21 vieret successivement en regard de la Partie conique 18, de la Partie cylindrique 20, de la Partie conique 19 et de la Partie cylindrique 17 dudit organe 14. Par consequent, la dimen- siou, du Passage utile par lequel l'huile peut s'ecouler depuis 1'interieur jusqu'ä 1'exterieur du piston 9 est dMerminee par Forgane regulateur de vitesse 14. La vitesse ä laquelle se fait la montee du piston 9 depend de celle ä laquelle l'huile peut s'echapper hors du piston. Par consequent, la montee du piston 9 se Fait d'abord tres lentement Pen dant que 1e moule est separe d'avec 1e mo dele ou vice versa. Quand 1e demoulage a eu lieu, la vitesse du piston 9 augmente puisque la Partie 19 de Porgane regulateur 14 passe dans le collet 21. La vitesse maximum est atteinte quand la Partie 20 de Forgane 14 est engagee dans 1e collet. Cette vitesse subsiste jusqu'ä ce que 1e bas de la Partie 19 de Forgane 14 penetre dann 1e collet. A partir de ce moment, la montee du piston 9 se fäit ä une vitesse qui diminue -graduelle- ment jusqu'ä ce que la Partie 17 de Forgane 14 s'engage dans 1e collet 21 et que 1e piston 9 se deplace avec une vitesse minimum. Le demoulage effectif se fait donc tres lentement et doucement, la vitesse de montee se fait rapidement Pendant la Partie intermediaire de la course et elle diminue au bout de la course afin que 1e mecanisme puisse s'arreter sans choc. Mais, comme explique ei-dessus, comme la section transversale utile du pis- ton 27 est sensiblement egale ä celle de Fes pace annulaire 32, 1e piston 27 monte en synchronisme avec 1e piston 9. Comme les tetes 4 et 5 sont solidaires respectivement des pistons 9 et 27, tous les bras 3 se Upla- cent ensemble vers 1e haut. The distributor is then brought to the position at which compressed air is held in conduit 41 and is also admitted into conduit 38. Compressed air, passing through conduit 38 and flexible connector 39, enters the head 4 by the first outlet 40 where this air vieret act between the oil contained in the first piston 9 and the upper wall of the head. As this is fair, the pressure is exerted on the oil which is discharged downwards in the interval comprised between the part 15 of the speed regulator 14 and the collar 21 and, from 1 to the opening 13. into the notches 16 made in the bottom of the cylinder 11 to push the pistons 12 and 9 upwards. During the rise of the pistons 12 and 9, the first collar 21 remains applied On its intended seat On the internal face of the bottom of the piston 9 (fig. 2), So that the first effective flow of the oil, from the inside of the piston 9 into the space below the pistons and in the cylinder 11, is determined by the collar 21 and the speed regulator member 14. the cylindrical part 20, of the conical part 19 and of the cylindrical part 17 of said member 14. The speed at which piston 9 rises depends on the rate at which oil can escape from the piston. Consequently, the rise of the piston 9 takes place very slowly at first while the mold is separated from the mold or vice versa. When stripping has taken place, the speed of piston 9 increases as Part 19 of regulating member 14 passes through collar 21. Maximum speed is reached when Part 20 of member 14 is engaged in the collar. This speed remains until the bottom of Part 19 of member 14 enters the collar. From this moment, the rise of the piston 9 takes place at a speed which gradually decreases until the Part 17 of the member 14 engages in the collar 21 and the piston 9 moves with a speed minimum. The actual stripping is therefore very slow and gentle, the rising speed is rapid during the intermediate part of the race and it decreases at the end of the race so that the mechanism can stop without shock. But, as explained above, since the useful cross-section of the piston 27 is substantially equal to that of the annular space 32, the piston 27 rises in synchronism with the piston 9. As the heads 4 and 5 are integral respectively with the pistons 9 and 27, all arms 3 move together upwards.

Quand les organes doivent eire ramenes ä leurs positions initiales, 1e distributeur 37 est d'abord ramene ä la Position pour laquelle 1e conduit 38 est mis en communication avec 1'echappement et pour laquelle la Pression est maintenue dans 1e conduit 41. De cette maniere la Pression de Pair cesse d'agir Sur 1'huile dans la tete 4. Le poids du mecanisme oblige les pistons 9 et 27 ä des cendre Jans leurs cylindres respectifs. La descente du piston 9 refoule l'huile par- dessous 1e piston 12 et vers 1e haut ä travers Fouverture 13 jusqu'ä Finterieur du piston 9, ce qui provoque 1e soulevoment du collet 21, de Sorte qu'un Passage de section transversale plus Brande se presente pour l'huile quand 1e piston 9 descend que lorsqu'il monte. 11 en resulte que les tetes 4 et 5 et les bras 3, qui en sont solidaires, peuvent descendre ä une vitesse relativement elevee. When the members must be returned to their initial positions, the distributor 37 is first returned to the position for which the conduit 38 is placed in communication with the exhaust and for which the pressure is maintained in the conduit 41. In this way the air pressure ceases to act on the oil in the head 4. The weight of the mechanism forces the pistons 9 and 27 to ash in their respective cylinders. The descent of piston 9 forces oil under piston 12 and upwards through opening 13 to the interior of piston 9, causing collar 21 to lift, so that a larger cross-sectional passage Brande shows up for the oil when the piston 9 goes down than when it goes up. As a result, the heads 4 and 5 and the arms 3, which are integral with them, can descend at a relatively high speed.

Quand 1e piston 9 descend, 1e volume de 1'espaee annulaire 32 augmente ä mesure que 1e volume de Fespace compris entre 1e piston 27 et 1e cylindre 25 diminue, de Sorte que l'huile est refoulee vers la droite, par rapport aux fig. 1, 2 et 3, par 1e conduit 29. As the piston 9 descends, the volume of the annular space 32 increases as the volume of the space between the piston 27 and the cylinder 25 decreases, so that the oil is forced to the right, with respect to FIGS. 1, 2 and 3, through the first conduit 29.

Quand ]es pistons 9 et 27 ont atteint 1e bas de leurs courses respectives, 1e distri- buteur 37 est ramene ä la Position pour la- quelle 1e conduit 41 communique avec 1'e- chappement Pendant que 1e conduit 38 con- tinue ä communiquer avec celui-ei, ce qui permet ä la soupape 34 de s'ouvrir. La fonc- tion de la soupape 34 est d'assurer qu'au debut du demoulage tour les conduits, ca- vites et espaces soient remplis complUement avec de 1'huile sans que de Fair, qui est com- pressible, sofft emprisonne dans ces conduits ce qui pourrait donner lieu ä des mouve- ments irreguliers des pistons 9 et 27. Tous les organes sont donc prets ä commencer un cycle suivant. When the pistons 9 and 27 have reached the bottom of their respective strokes, the distributor 37 is returned to the position for which the conduit 41 communicates with the exhaust. with it, allowing valve 34 to open. The function of valve 34 is to ensure that at the start of stripping all the ducts, cavities and spaces are completely filled with oil without air, which is compressible, being trapped in these. driven which could give rise to irregular movements of the pistons 9 and 27. All the organs are therefore ready to begin a following cycle.

Claims

CLAIM Device for separating a mold from the model used in its manufacture, characterized in that it comprises a Small cylinder and a Brand cylinder arranged in tandem, a Small hollow piston sliding in the Small cylinder and having an extension penetrating into the 1st Brand cylinder, a Brand piston sliding in the Brand cylinder and Carried by the extension, the extension and the Brand cylinder delimiting an annular space, means for admitting fluid under pressure directly into the hollow piston, the Brand piston having an opening through which the pressurized fluid is admitted behind the 1st Brand piston and into the 1st Brand cylinder to move the 1st Small and 1st Brand piston, a third piston movable along a path parallel to the path of the Small piston, the 1st Brand piston being provided to drive fluid out of the annular space for actuating the third piston, the area of the section of the annular space being substantially equal to the effective area of the third piston against which the fluid expelled from the annular space acts, and in that the small and the third piston include means for acting on one of the molded or modeled elements, in order to cause leer Separation. 1. Device according to claim, characterized in that it comprises an elongated flow control member, of non-uniform section, integral with the Brand cylinder and penetrating into the first hollow of the Small piston through the said opening of the brand piston to partially close it, the first relative movement between this member and said opening having the effect of varying the speed of admission of the fluid behind the first brand piston and hence the speed of the three pistons and the speed with which the first mold and the model are separate.

2. Device according to claim, characterized in that it comprises means cooperating with a flow adjustment member and which are placed in an active position while the first fluid is sent from inside the hollow piston. at the rear of the Brand piston in the Brand cylinder, to reduce the effective area of said opening, and which are placed in a non-operating position During the passage of the fluid through the opening in the other direction, so that the speed the displacement of the three pistons during the separation of the mold and the model is smaller than their speed in the opposite direction.

3. Device according to sub-claim 2, characterized in that the said means cooperating with the flow adjustment member are constituted by a collar having internal dimensions smaller than the opening.

4. Device according to sub-claim 1, characterized in that the flow adjustment member has a part whose section is relatively large and which is intended to be located in said opening at the moment when the separation of the mold and the model begins. , and a portion whose cross-section is relatively small and which is intended to be located in the opening a moment later to increase the flow of fluid through the opening.

5. Device according to claim, characterized in that the first small cylinder and the first large cylinder are arranged vertically, the first small cylinder being arranged above the large cylinder, the first hollow piston whose upper end is closed being intended to contain a liquid, in that it comprises a source of gas under pressure, a conduit from the source to the interior of the hollow piston, a Passage connecting the interior of the hollow piston to a point located in the large cylinder below of the large piston, so that the pressurized gases introduced into the hollow piston through the pipe force the liquid to raise the three pistons, in that it comprises a third cylinder arranged vertically, in which the third slides piston, a pipe connecting the upper end of the said annular space to a point located in the third cylinder below the third piston, another pipe connecting the space in front of the large piston with the space behind it. here, a valve arranged in this conduit, a conduit between the source of gas under pressure and the valve for closing the latter and means for controlling the flow of gas under pressure from the source and going through the respective conduits.

6. Device according to sub-claim 5, characterized in that said valve is normally open and in that said control means are constituted by a valve which can be actuated to admit the pressurized gas coming from this source, either towards said valve only in order to close it, or simultaneously towards said valve and in the upper end of the hollow piston.