Process and device for thin sheet press sticking on furniture panel

Description

[0001] The invention relates to a process and relative equipment for veneering through a veneer press thin layers on curve and/or flat surfaces, particularly for production of panels, as for instance the panels for small doors used in furniture production.

[0002] The equipment could be more particularly applied to the planes of the usual presses for furniture panel production or be the main characteristic of a specific press for non-flat surfaces.

[0003] Therefore a further object of the present invention is a press provided with such equipment or system fit to realize the process constituent the characteristic form of the present invention.

[0004] The methods of pressing for glueing thin layers, as for instance valuable wood layers, on curve surfaced panels, are well known in prior art, as for instance the process of pressing with oil-cushion. The use of such a system allows the veneer or layer, through the utilization of a cushion containing a fluid, normally hydraulic oil, to fit perfectly to the shape of the panel producing its shaping on the panel surface with glueing; but this is a specific solution.

[0005] Other well known methods of pneumatic veneering are very expensive because the pressing plates have a cushion usually heated using a diathermic oil that requires a long time to get hot. Also the utilization of pneumatic presses with electric resistance heating plates is not efficient, so that several industries are looking for an alternative, more profitable, simple and more efficient method of glueing.

[0006] The purpose of the present invention is the realization of a new process of veneering or glueing thin layers on panels with variously shaped surface allowing the utilization also with flat surface and furthermore allows the glueing, besides on the larger external surface of the panel, also on the perimetric surfaces and this using low-cost equipments and with a very efficient, profitable process.

[0007] This problem is solved by the subject matter of claims 1 and 4.

[0008] On this basis the invention solves the problem utilizing a veneering method under the effects of the pressure and/or vacuum obtained on a rubber sheet with the pneumatic action of compressed air on one side and the vacuum caused by a vacuum pump on the other side.

[0009] In order to accelerate the glueing, heat is transmitted to the pieces through a rubber sheet previously heated by contact with the hot surfaces of the pressing plates and preferably the inlet of heated compressed air.

[0010] The intervention times of the pressures through the available temperatures and used materials (layer thickness, type of rubber, etc). are regulated by a preferably automatic cycle previously set.

[0011] Standard equipment according to the invention is more particularly constituted by:

a metal frame of a pre-established size, with connecting means to be connected to the upper pressing plates;

a rubber sheet of an adequate thickness and preferably of about 3 mm., heat resistant, whose sizes are slightly larger than those of the frame to which it has to be hung;

an insulated air bag, with heat-exchanger to be connected to the net of compressed air or to a compressor;

a volumetric vacuum pump;

an electro-valve set;

an electric-pneumatic control board with cycle computer.

[0012] This embodiment is to be applied in a press system as above-stated to carry out the pressing of a panel whose surface has to be covered, after being smeared with glue, with a thin covering, like a valuable wood layer or veneer and pressed between the lower pressing plate and the upper pressing plate of the press with the overhanging interposition of said rubber sheet in co-operation with the action of two opposed chambers, an upper one "A" and a lower one "B" respectively, in which through a vacuum action in the upper chamber to suck back and heat the rubber sheet, pressing and vacuum action in the lower chamber or pressure in the upper chamber, the recoil down of the rubber sheet is allowed to make it adhere perfectly to the shape of the panel to cover, shaping in the same way under pressure the veneer, which under said pressure action of the rubber sheet and of the heat will glue on the covered panel surface.

[0013] The advantages offered by the invention are mainly:

on the usual presses for the furniture-makers that have a large working area, it is possible to set up several of these equipments allowing the increase of production with many panels each plane;

a very low running cost can be realized because it is possible to heat the plates sooner with the heat sources already existing in the works (water, oil, etc.) thus eliminating all the negative consequences which are caused by the use of diathermic oil in the hydraulic cushions when they break causing the leakage of oil, as it is proved that the breakage of said cushions is extremely easy;

the maintenance is reduced to a minimum;

possible breakages of the rubber sheets do not. compromise the carrying on of the work, as it is possible to stop the leak (temporarily) with the application of any patching as a pad, not excluding, when the breakage concerns the central plane, the utilization of an overhanging particle board panel;

it is not necessary to protect the wood layer against the stretching because they do not occur (which allows to eliminate the utilization of valuable, strengthened wood layers, etc.); furthermore, obvious free movements are acquired which facilitate the work process allowing saving of preparation for the wood layer;

it is possible to press surfaces in cod, reaching very high limits, changing the plate or rubber sheet elasticity;

the produced panels, having been pressed under vacuum, come out completely dry, thanks to the removal of the damp produced by the steam of the glue during the same glueing, with the consequent advantage that the pieces produced in this way do not undergo deformations and the painting is then facilitated, without considering that the work environment is free from pollution by noxious gas produced by the chemical reaction of the glue because due to the under vacuum system said fumes are sucked in by the pumping system of the pump which causes the vacuum and then ejected to the outside.

[0014] The above mentioned characteristics, better pointed out in the annexed claims, will be better understood and illustrated with the help of the following detailed description of a preferred embodiment of the invention and in accordance with the illustrative representations of the three enclosed sheet of drawings in which:

Figure 1 is a schematic view in trasversal vertical section in frontal elevation of the equipment applied to the press before the pressing stage;

Figure 2 is a view of the schematic representation of Figure 1 in which the behaviour of the rubber sheet "G" under the depression action applied to the upper chamber and without the pressing of the panel to cover with the wood layer to glue is visualized;

Figure 3 and 4 are a schematic representation of a panel "P" whose upper and lateral surfaces have to be covered through the glueing with a thin wood layer (veneer) "T" after the said smearing as explained before on the glueing surfaces;

Figure 5 is the pressing step with the lifting of the lower pressing plate in which the pressing of the wood layer "T" against the sheet "G" is carried out;

Figure 6 is a schematic representation, like the preceding one, in which it is illustrated the pressing step in the upper chamber "A" overhanging the flexible rubber sheet "G" and the vacuum forming in the lower chamber "B" due to the recall of the rubber sheet "G" to the layer "T" around the surfaces to glue;

Figure 7 is a solution with two flanked equipments. As it can be seen in the above mentioned figures the equipment consists therefore of support means constituted by a perimetric airtight frame 1, through fixing systems on the upper plate 2 of the press and with the inter- mediation of an airtight annular packing 3.

[0015] Said airtight frame "1" has the shape of a top and bottom opened box supplied with at least one piping 4 for the connection of the inner chamber "A" with the outside for the passage of a fluid which can be put in or taken from the chamber "A" under pressure or depression with suitable means of pressure and vacuum formation (not represented).

[0016] Perimetrically through fixing and elastic stretching systems 5 a flexible and elastic rubber sheet "G" is stretched, which, under the depression action through suction of the air contained in chamber "A" can be deformed as represented in Figure 2 coming elastically in perfect contact and adhesion with the surface of the upper plate 2 of the press. The lower plate of the press, which for this purpose can move up and down for the pressing operation 6, is supplied with a piping 7 reentering the inner perimeter of chamber "A" defined by the perimetric frame 1 and furthermore on the movable lower plate 6 there is a support "D" fit to support the panel to be pressed "P" whose upper and lateral external surface has to be covered through the glueing of a wood layer of flexible type "T" as represented in Figure 2. The piping 7 of the lower plate 6 will obviously be connected to the well known means of operating of a pump to realize a depression in the lower chamber "B" which takes place after the pressing operation of Figure 5 between the flexible rubber sheet "G" and the lower plate 6 to get a vacuum action starting from a position as representated in Figure 5 to shape, through the depression action, the rubber sheet "G" as represented in Figure 6; and this with the operating of the depression means which preferably is also suitable for operating in the piping 4 of the upper plate 2 alternatively as follows: operating of the vacuum in the upper chamber "A", pressing, operating of the depression in the lower chamber "B" by vacuum action in the outlet 7 of the lower plate 6 with free atmospheric pressure on the upper chamber "A" or under pressure by means of the inlet realizing with such an operation the glueing under the temperature and pressure action as represented in Figure 6.

[0017] More particularly to obtain the quick glueing and the complete polymerisation the upper plate of the press 2 will be brought to a temperature of 95-120°C and in the same way the lower plate of the press will be brought at the same or about at the same temperature, more or less according to the specific requirements.

[0018] With such a system also the heating of the rubber sheet "G" will thus be carried out and it will transmit heat to the wood layer to be pressed and the lower plate 6 will transmit heat to the panel to be glued.

[0019] A further system to acclerate the glueing will be carried out through the utilization of inlet of preheated air in such a way to accelerate the glueing and polymerisation system.

[0020] The process steps are essentially:

when the equipment is at rest the so equipped press is as represented in Figure 1 and the frame 1 fixed on the upper plate of the press will hold the rubber sheet "G" well stretched through a packing of lesser tightness of contact 8;

before starting the production cycle the vacuum in chamber "A" will be carried out and the rubber sheet "G" will be made to adhere to the lower surface of the upper plate of the press which for this purpose is heated at 95-120°C thus heating through conduction at direct contact the rubber sheet "G";

in the meantime the parts to glue will be prepared as represented in Figures 3, 4 smearing some glue on the panel to be covered "P" or applying on the wood layer to be covered "T" a possible further smearing of glue also on the free lateral surfaces, keeping in mind that the glue smearing can be applied both on the rough panel to be covered and on the wood layer according to the specific requirements and the available equipments;

then the panel "P" with its veneer "T" with their support "D" will be placed on the lower plate 6 of the press system as represented in Figure 2;

at last the lower pressing plate will be lifted under the pressing action to press the two pieces to glue "P", "T" as represented in Figure 5;

this pressing operation carried out, the vacuum in the upper chamber "A" will be taken away and it will be applied to the lower chamber "B" and all will be combined with the inlet of hot fluid under pressure in the upper chamber "A" as represented in Figure 6, thus completing the pressing operation and relative glueing;

then the pressures are reversed realizing again the depression in the upper chamber "A" and the opening of the plates takes place with a perfectly reversed process for the removal of the piece so glued.

[0021] It stands to reason that with the closing of the press the two pieces to glue are compressed between the two hot plates of the same press getting hot and the pressure of the machine will press the wood layer under the rubber sheet in such a way that it cannot undergo stretchings during the extension of the said rubber sheet in the parts not concerned of the flat surfaces and consequently breakages cannot occur. This mechanical pressure will increase further on the specific pressure in that part of the piece without increasing the necessary pneumatic pressures for the curve surfaces thus allowing a reduction of the resistant moments of the frame of the same press developing also a levelling action on the flat surface of the panel eliminating possible stag- nations of glue, etc... After the closing of the press, the valves arranged and programmed on purpose with the cycle will reverse the flow of the fluids in the chambers "A" and "B" starting the very step of the glueing of the remaining surfaces which, as already mentioned at the beginning, takes place for the combined action of the pneumatic pressure in the upper chamber "A" and the pneumatic depression in the lower chamber "B" and the mechanical pressure in the upper flat part of the piece.

[0022] The rubber sheet "G" preheated by contact with the hot parts of the press, lying on the curve surfaces of the piece will carry heat and give this heat to the glueing surfaces of the same piece through the respective wood layer of covering. At the same time the compressed and preheated air in the upper chamber "A" will contribute to give heat by the rubber sheet to the curve parts that cannot receive heat from the heated upper plate 2, thus reducing to a minimum the drying and hardening times of the same glue.

[0023] The pressure of the compressed air will be regulated in accordance to the shape of the pieces and their number; anyhow, the value cannot exceed that of the setting of the highest pressure valve installed on the bag whose values will be calculated on the basis of the mechanical resistances offered by the frame.

[0024] For the opening of the press the automatically piloted electro-valves (not represented but of a well known type) will obviously intervene after a predetermined time reversing the flow of the fluids in the chambers "A" and "B" of the frame and thus setting the rubber sheet in the starting position as said in the condition preceding the pressing, so starting another preheating step of the rubber sheet which will last all the necessary time for discharging the glued pieces and smearing and introducing the new ones.

[0025] After having resettled the pressure balances between chambers "A" and "B" another automatic control impulse will cause the opening of the press thus including the pressing cycle, obviously followed by the discharge of the same pieces. Of course, all the execution details can change but without altering the innovatory substance of the invention as described, illustrated and essentially below claimed.

Claims

1. Process for glueing through pressing a thin layer (T) on a curved and/or flat surface, especially for the covering with thin wood layers through glueing or veneering of furniture panels (P), using a press having an upper heated pressing plate (2) and a lower heated pressing plate (6) movable in a pressing position, characterized in that an airtight support frame (1) is placed between said upper (2) and lower (6) pressing plates respectively of said press and in which said support frame (1) supports a flexible sheet (G) perimetrically stretched with elastic means of stretching (5) in order to provide an airtight chamber (A) with the fitted upper pressing plate (2), said chamber (A) being connected by a connecting duct means (4) to a pressure/vacuum means to produce different pressure in said chamber (A) as compared with that on the outside, wherein for the veneering the following steps are carried out:

on the panel (P) surface to be veneered glue is smeared and the layer (T) is placed on it, the assembly being placed on the lower pressing plate (6), in the meantime or before the vacuum has been produced in chamber (A) to suck the said flexible sheet (G) back onto the lower surface of the preheated upper pressing plate 2

the pressing between the upper plate and the lower plate respectively (2 and 6) of the press, heated for this purpose, is carried out thereby pressing the pieces to be glued (P and T) between the lower plate and the upper plate respectively;

the vacuum in the upper chamber (A) is taken away and then air is conveyed under pressure in the same chamber (A) to push down the said flexible sheet (G) around the perimetric edge of the panel (P) whose layer (T) has to be glued;

the pressure is kept in such a condition for a suitable time till the completion of the glueing, then the pressure in the upper chamber (A) is taken away and the vacuum is re-applied bringing again the said flexible sheet (G) in contact with the lower surface of the upper pressing plate (2);

the separation between the pressing plates, upper (2) and lower (6) respectively, is carried out and the glued piece is taken away and the cycle starts again.

2. Process as claimed in claim 1 characterized in that the air put in the upper chamber (A) under pressure is heated.

3. Process as claimed in claims 1 and/or 2, characterized in that the lower plate (6) is supplied with a duct toward the outside (7) opened in the area under the upper chamber (A) to realize a connection with a lower annular chamber (B) and connected with vacuum means to co-operate in the step in which, after the pressing, an air pressure is realized in the upper chamber (A).

4. Equipment, applicable to a press with heated upper pressing plate and lower pressing plate under the upper pressing plate, to carry out the process as claimed in any preceding claims, comprising at least:

a metallic bottom and open-top box frame (1) with airtight connecting means (3) to the lower surface of the upper pressing plate (2) and with perimetrically annular elastic stretching means (5) to stretch a flexible and elastic sheet (G) in airtight connection with the perimetrical annular lower edge (8) of the box frame (1) to provide an airtight chamber (A), and supplied at least with a duct (4) for the passage of a fluid;

a vacuum/pressure device connected with said duct (4) to produce the vacuum in said chamber (A) or a pressure alternatively in a programmed amount and for a preset time;

control means for the vacuum/pressure device to produce the vacuum and thus the suck back of the flexible and/or elastic sheet (G) against the upper pressing plate supporting the box frame (1) or to push off said sheet (G) from said plate surface;

5. Equipment as claimed in the preceding claim, in which said vacuum/pressure means are connected with an insulated bag, a heat exchanger, and an air vacuum compressor device pump.

6. Equipment as claimed in the two preceding claims, characterized in that the opposed lower pressing plate (6) is also supplied with a duct (7) flowing in the lower chamber (B) opposed to the upper chamber (A) realized wiht the separation through the elastic movement of said flexible and elastic sheet (G), said duct (7) being connected with a vacuum device or with the same vacuum device of the opposed chamber (A) to carry out the alternate vacuum either on one or on the other opposed chambers.

7. Equipment as claimed in the three preceding claims, characterized in that the control system is integrated with an electro-valve set, fit to deviate, open and close the flows of the fluid, in this specific case compressed air, for the alternate inlet or withdrawal in the respective opposed chambers (A) and (B) in which said working is programmed and carried out through an electric pneumatic control set with cycle computer.

8. Equipment as claimed in any of the preceding claims, characterized in that the support frame (1) of the flexible and/or elastic sheet (G) is fixed to the upper plate of the press (2) and in which the lower plate of the press (6) is supplied with an interchangeable spacer (D) set to support the pieces to be pressed and glued and in which the support (1) is connectable with extension means to vary its height.

9. Press or plant supplied with an equipment as claimed in any of the preceding claims and fit to carry out the process as claimed in claims 1, 2, 3 with more than one of the claimed equipments placed on the pressing plate.

Ansprüche

1. Verfahren zum Aufkleben durch Pressen einer dünnen Schichte (T) auf eine gekrümmte und/oder ebene Oberfläche, insbesondere zur Beschichtung mit Holzsichichten durch Verkleben oder zum Furnieren von Möbletafeln (P) unter Verbindung einer Presse mit einer geheizten oberen Preßplatte (2) und einer geheizten unteren Preßplatte (6), die in eine Preßposition bringbar ist, dadurch gekennzeichnet, daß zwischen die obere (2) und untere (6) Preßplatte der Presse ein luftdichter Tragrahmen (1) gebracht wird und dieser Tragrahmen (1) eine flexible Lage (G) trägt, welche rundherum mit elastischen Spannmitteln (5) gespannt wird, um eine luftdichte Kammer (A) mit der befestigten oberen Preßplatte (2) zu schaffen, wobei diese Kammer (A) mittels einer Rohrverbindungseinrichtung (4) an eine Druck/Unterdruck Einrichtung angeschlossen ist, um in dieser Kammer (A) einen Druck hervorzurufen, der verschieden ist von dem Außendruck und wobei zum Furnieren die folgenden Schritte durchgeführt werden:

- auf die Oberfläche der Tafel (P), die zu furnieren ist wird Klebstoff aufgebraucht und die Lage (T) wird daraufgelegt, die Anordnung wird auf die untere Preßplatte (6) gebracht, wobei in der Zwischenzeit oder zuvor in der Kammer (A) der Unterdruck erzeugt wird um die flexible Lage (G) auf die untere Oberfläche der vorgeheizten oberen Preßplatte 2 zurückzusaugen;

- das Pressen zwischen den für diesen Zweck erhitzten oberen bzw. unteren Platte (2 und 6) wird durch Pressen der zu verklebenden Teile (P und T) zwischen der unteren Platte bzw. der oberen Platte durchgeführt; -

- in der oberen Kammer (A) wird der Unterdruck abgebaut und daraufhin wird in dieselbe Kammer (A) Luft unter Druck eingebracht, um die flexible Lage (G) nach unten, um die herumlaufende, Kante der Tafel (P), deren Schicht (T) zu verkleben ist, zu drücken;

- der Druck wird in diesem Zustand für eine geeignete Zeitdauer bis zum Abschluß des Verklebens gehalten, sodann wird der Druck in der oberen Kammer (A) abgebaut und wiederum ein Unterdruck angelegt, wobei die flexible Lage (G) in Kontakt mit der unteren Oberfläche der oberen Preßplatte (2) gebracht wird;

- die Trennung zwischen der oberen (2) bzw. unteren (6) Preßplatte wird durchgeführt, das verklebte Stück wird entfernt und der Zyklus beginnt von neuem.

2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die in die obere Kammer (A) unter Druck eingebrachte Luft erhitzt wird.

3. Verfahren nach Anspruch 1, und/oder 2, dadurch gekennzeichnet, daß die untere Platte (6) mit einer nach außen führenden Leitug (7) versehen ist, die im Bereich unterhalb der oberen Kammer (A) geöffnet ist, eine Verbindung mit einer unteren ringförmigen Kammer (B) bildet und mit einer Vakuumeinrichtung verbunden ist, um in jenem Schritt zusammenzuarbeiten, in dem, nach dem Pressen, ein Luftdruck in der oberen Kammer (A) aufgebaut wird.

4. Vorrichtung, anwendbar auf eine Presse mit einer geheizten oberen Preßplatte und einer unterhalb der oberen Preßplatte gelegenen unteren Preßplatte zur Durch führung des Verfahrens nach irgend einem der vorhergehenden Ansprüche, die zumindest enthält:

- einen metallischen, oben und unten offenen Kastenrahmen (1) mit luftdichten Verbindungsmitteln (3) zu der unteren Oberfläche der oberen Preßplatte (2) und mit herumlaufenden, ringförmigen, elastischen Spannmitteln (5) zum Spannen einer flexiblen und elastischen Lage (G) für deren luftdichte Verbindung mit der rundumlaufenden unteren Kante (8) des Kastenrahmens (1) unter Bildung einer luftdichten Kammer (A), und mit zumindest einer Leitung (4) zur Durchleiten eines Fluidums;

- eine Unterdruck/Druckeinrichtung, die mit dieser Leitung (4) verbunden ist, um in dieser Kammer (A) abwechselnd, in vorgegebenem Ausmaß und für eine festgesetzte Zeit jeweils einen Unterdruck oder einen Überdruck zu erzeugen;

- Steuereinrichtungen für die Unterdruck/Überdruckeinrichtung, um einen Unterdruck zu erzeugen und hiedurch die flexible und/oder elastische Lage (G) gegen die obere, den Kastenrahmen (1) tragende Preßplatte zurückzusaugen oder um diese Lage (G) von dieser Plattenoberfläche abzustoßen.

5. Vorrichtung nach dem vorgehenden Anspruch, bei welcher die Unterdruck/Überdruckeinrichtung mit einem isolierten Beutel, einem Wärmetauscher und einer Luft-Vakuum-Kompressor-Pumpe verbunden ist.

6. Vorrichtung nach den zwei vorgehenden Ansprüchen, dadurch gekennzeichnet, daß die gegenüberliegende untere Druckplatte (6) gleichfalls mit einer Leitung (7) versehen ist, die in die untere, der oberen Kammer (A) gegenüberliegende Kammer (B) führt, welche durch die Trennung mittels der elastischen Bewegung der flexiblen und elastischen Lage (G) gebildet ist, wobei diese Leitung (7) mit einer Vakuumeinrichtung oder mit derselben Vakuumeinrichtung der gegenüberliegenden Kammer (A) verbunden ist, zur abwechselnden Erzeugung eines Unterdruckes in der einen oder anderen der gegenüberliegenden Kammern.

7. Vorrichtung nach einem der drei vorgehenden Ansprüche, dadurch gekennzeichnet, daß das Steuersystem eine Magnetventilanordnung besitzt, die zur Umleitung, zum Öffnen und Schließen der Flüsse des Fluidums, in diesem speziellen Fall komprimierter Luft, geeignet ist, und abwechselnd die Zufuhr oder das Absaugen in den entsprechenden gegenüberliegenden Kammern (A) und (B) ermöglicht, wobei diese Vorgänge programmiert sind und mittels einer elektro-pneumatischen Steuereinrichtung mit einem Zykluscomputer durchgeführt werden.

8. Vorrichtung nach einem der vorgehenden Ansprüche, dadurch gekennzeichnet, daß der Tragrahmen (1) der flexiblen und/oder elastischen Lage (G) an der oberen Platte (2) der Presse befestigt ist und daß die untere Platte (6) der Presse mit einem auswechselbaren Abstandshalter (D) versehen ist, welcher die zu pressenden und klebenden Stücke trägt und daß der Träger (1) mit Verlängerungsmitteln zur Änderung seiner Höhe verbindbar ist.

9. Presse oder Anlage, ausgerüstet mit einer Einrichtung nach irgend einem der vorgehenden Ansprüche und geeignet zur Ausführung des Verfahrens nach den Ansprüchen 1,2,3 mit mehr als einer der auf der Preßplatte angeordneten, beanspruchten Einrichtungen.

Revendications

1. Procédé de collage par pressage d'une fine couche (T) sur une surface courbe et/ou plane, spécialement déstiné au revêtement à l'aide de fines couches en bois par collage ou placage des panneaux (P) de meubles, à l'aide d'une presse comportant une plaque de pressage supérieure chauffée (2) et une plaque de pressage inférieure chauffée (6) mobiles en position de pressage, caractérisé en ce qu'un cadre de support étanche à l'air (1) est placé entre lesdites plaques de pressage supérieure (2) et inférieure (6) de la presse et en ce que le cadre support (1) supporte une feuille flexible (G) étirée sur tout le périmètre à l'aide de moyens élastiques d'étirage (5) réalisant ainsi une chambre étanche à l'air (A) avec la plaque de pressage supérieure (2), ladite chambre (A) étant raccordée par une tuyauterie de raccordement (4) sur des dispositifs de mise en pression/vide destinés à fournir des pressions différentes dans ladite chambre (A) comparées à la pression extérieure, le plaquage étant réalisé à partir des operations suivantes:

sur la surface du panneau (P) devant être plaqué la colle est appliquée et la couche (T) est positionnée sur la surface, l'ensemble étant placé sur la plaque de pressage extérieure (6), simultanément ou avant la réalisation du vide dans la chambre (A) pour rappler la feuille flexible (G) sur la surface inférieure de la plaque de pressage supérieure préchauffée 2:

le pressage entre la plaque supérieure et la plaque inférieure respectivement (2 et 6) de la presse, chauffées à cet effet, est réalisé par pressage des pièces à coller (P et T) respectivement entre la plaque inférieure et la plaque supérieure;

le vide dans la chambre supérieure (A) est éliminé et l'air est envoyé sous pression dans la même chambre (A) pour ramener vers le bas ladite feuille flexible (G) sur tout le périmètre du panneau (P) dont la couche (T) doit être collée;

la pression est maintenue à l'état adapté au temps nécessaire à la réalisation du collage, puis la pression dans la chambre supérieure (A) est éliminée et le vide est réappliqué ramenant à nouveau ladite feuille de caoutchouc (G) en contact avec la surface inférieure de la plaque de pressage supérieure (2);

la séparation entre les plaques de pressage, respectivement supérieure (2) et inférieure (6) est effectuée et la pièce collée est retirée et le cycle recommence.

2. Procédé selon la revendication 1 caractérisé en ce que l'air de la chambre supérieure (A) sous pression est chauffée.

3. Procédé selon les revendication 1 et/ou 2, caractérisé en ce que la plaque inférieure (6) est munie d'une tuyauterie de sortie (7) ouvertre dans la zone située sous la chambre inférieure (A) afin de réaliser une liaison avec une chambre circulaire inférieure (B) et reliée par des moyens de mise sous vide pour contribuer au cours de l'opération, après pressage, de mise en pression de l'air dans la chambre supérieure (A).

4. Dispositif, applicable à une presse munie d'une plaque de pressage supérieure chauffée et d'une plaque de pressage inférieure sous la plaque de pressage supérieure, pour permettre la réalisation du procédé décrit dans les revendications précédentes, comportant au moins:

un cadre (1) métallique à la partie inférieure et ouvert à la partie supérieure muni de moyens (3) de raccordement étanches sur la surface inférieure de la plaque de pressage supérieure (2) et de moyens (5) d'étirage élastique et circulaire pour étirer une feuille (G) élastique et flexible reliée d'une manière étanche avec le bord inférieur (8) circulaire du périmètre du cadre (1) pour réaliser une chambre (A) étanche, et équipé d'au moins une tuyauterie (4) destinée au passage d'un fluide;

un dispositif de mise en pression/vide relié à ladite tuyauterie (4) pour réaliser le vide dans ladite chambre (A) ou une pression à un niveau prédéterminé et un temps préréglé;

moyens de contrôle du dispositif de mise en pression/vide permettant d'établir le vide et ainsi de rappeler la feuille (G) élastique et/ou flexible contre la plaque de pressage supérieure supportant le cadre (1) ou pour repousser ladite feuille (G) de la surface de la plaque;

5. Equipement selon la revendication précédente, caractérisé en ce que les moyens de mise en pression/sous vide sont reliés par un sac isolé, un échangeur de chaleur et une pompe à vide.

6. Dispositif selon les deux revendications précédentes, caractérisé en ce que la plaque (6) de pressage inférieure opposée est également munie d'une tuyauterie (7) reliée à la chambre inférieure (B) opposée à la chambre supérieure (A), la séparation par le mouvement élastique de ladite feuille élastique (G) et flexible, ladite tuyauterie (7) étant relié par un dispositif à vide ou au même dispositif à vide de la chambre opposée (A) afin de réaliser le vide dans l'une ou l'autre des deux chambres opposées.

7. Dispositif selon les trois revendications précédentes, caractérisé en ce que le système de commande est intégré à un ensemble électrovanne, destiné à dévier, ouvrir ou fermer le débit du fluide, dans ce cas spécifique, l'air comprimé, pour l'entrée ou le retrait des chambres opposées respectivement (A) et (B) dans laquelle les opérations sont programmées et réalisées à l'aide d'un ensemble de commandes pneumatiques électriques par un calculateur de cycles.

8. Dispositif selon l'une des revendications précédentes, caractérisé en ce que le cadre (1) de la feuille (G) élastique et/ou flexible est fixée sur la plaque supérieure de la presse (2) et en ce que la plaque inférieure de la presse (6) est munie d'une entretoise (D) interchangeable destinée à supporter les pièces à presser et coller et en ce que le support (1) peut être relié par l'intermédiaire de moyens de raccordement pour modifier sa hauteur.

9. Presse ou installation équipée d'un dispositif selon l'une des précédentes revendications et destiné à la réalisation du procédé défini dans les revendications 1, 2, 3 à l'aide de plus d'un des équipements placés sur la plaque de pressage.

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