WO2016139688A1

WO2016139688A1 - System for cooling a pre-laminated printed circuit board in transit between a pre-laminator and a laminator

Info

Publication number: WO2016139688A1
Application number: PCT/IT2015/000089
Authority: WO
Inventors: Osvaldo Novello; Francesco Parrinello
Original assignee: Automatic Lamination Technologies S.R.L.
Priority date: 2015-03-05
Filing date: 2015-03-30
Publication date: 2016-09-09

Abstract

The invention refers to a system (20) for cooling a pre-laminated printed circuit board in transit between a pre-laminator (4) and a laminator (6). The cooling system comprises: a conditioner (21) suitable for thermally conditioning ambient air, bringing it to a temperature preferably comprised between 8 °C and 12 °C, a distributor (22) communicating with the conditioner and suitable for creating a flow of conditioned air, at a substantially laminar condition, that hits the pre-laminated board, a filter (26) of HEPA type housed in the distributor, a thermocouple (27) for detecting the temperature of the conditioned air at the outlet of the distributor, and a control device (28) connected with the thermocouple and the conditioner for commanding the actuation thereof. In particular, the control device commands the actuation of the conditioner in a manner so as to bring and maintain the temperature of the conditioned air at the outlet of the distributor to/at value that is as close as possible to a predefined temperature. The invention also refers to a module (1) for conveying a pre-laminated printed circuit board from a pre-laminator (4) to a laminator (6), comprising the cooling system (20) that is the subject of the invention.

Description

SYSTEM FOR COOLING A PRE-LAMINATED PRINTED CIRCUIT BOARD IN TRANSIT BETWEEN A PRE-LAMINATOR AND A LAM I NATO R

Field of application of the invention

The present invention has application in the field of the art regarding the manufacturing of printed circuit boards (also known with the acronym "PCB").

The process for manufacturing a printed circuit board takes place in a plurality of steps, two of which being the "pre-lamination" of the board and the subsequent "lamination" thereof.

The pre-lamination consists of extending a film, preferably polymeric and by way of example photosensitive, on at least one sheet, preferably multilayer. By "multilayer sheet" it is intended a sheet preferably comprising multiple layers made of dielectric material superimposed on each other and covered on one or both faces by a layer of laminated copper. By "photosensitive film" it is intended a film suitable for preparing the copper lamina of the multilayer sheet for photo- etching, in order to obtain a printed circuit board.

In order to facilitate the exposition, hereinbelow in the present description with the expression "pre-laminated board", reference will be made to a multilayer sheet on which, one or both faces thereof, a photosensitive film was extended in order to obtain a printed circuit board. The apparatus through which the pre- lamination is carried out is usually indicated with the term "pre-laminator". A pre- laminated printed circuit board is therefore a product exiting from a pre- laminator.

The lamination consists of making the photosensitive film adhere to the sheet on which the film was extended within the pre-laminator. The apparatus through which the lamination is performed is usually indicated with the term "laminator". The pre-laminated printed circuit board, having exited from the pre-laminator, is therefore conveyed into the laminator.

Following the lamination, the product exiting from the laminator is subjected to photo-etching, which consists of chemically removing the "excess" copper through the photosensitive film (obtained, by way of example, with the technol- ogy well-known to those skilled in the art as photoresist technology), in a manner so as to transform the copper lamina of the multilayer sheet into a network of circuit connections. The non-removed film portion together with the excess copper becomes a layer of protection for said circuit connections (and hence of the printed circuit). Said protective layer is usually identified with the expression "welding mask".

In the scope of the process of producing a printed circuit board, the present invention has application during the step in which a pre-laminated board exiting from a pre-laminator is conveyed into a laminator. More precisely, the present invention refers to a system for cooling a pre-laminated board in transit between a pre-laminator and a laminator.

In a different aspect thereof, the present invention refers to a module for moving a pre-laminated printed circuit board from an outlet mouth of a pre-laminator to an inlet mouth of a laminator, simultaneously with the aforesaid cooling system. Illustration of the technical problem and review of the prior art

The surface of a sheet on which a photosensitive film is extendable for the purpose of obtaining a printed circuit board is generally non-uniform. This is due to the presence of microscopic and/or macroscopic reliefs and/or depressions resulting from the manufacturing process of the sheet, in particular a multilayer sheet. Due to this non-uniformity, when the photosensitive film is extended on the sheet within the pre-laminator, air inclusions are formed which remain trapped between the film and the sheet. These air inclusions must be removed by the laminator. Indeed, if the film is not made to completely adhere to the sheet opposed thereto, the air inclusions would compromise the photo-etching process and consequently the structure of the network of circuit connections. For the laminator to be able to remove the air inclusions, it is opportune that the photosensitive film does not adhere to the sheet before the entrance in the lam- inator. Unfortunately, this does not always occur since the adhesion capacity of the photosensitive film to the sheet is nearly proportional to the temperature of the film and, even if the air present in the environment within the pre-laminator is maintained at a suitably low temperature (by way of example, between 8 °C and 12 °C), during the conveyance of the pre-laminated board from the pre- laminator to the laminator, the board traverses an environment whose air is nearly at the same temperature as that present in the work environment (by way of example, between 22 °C and 27 °C). At the outlet of the pre-laminator, the pre-laminated board therefore starts to be heated and, since the entrance into the laminator cannot occur instantaneously, during the conveyance from the pre-laminator to the laminator, it can happen that the photosensitive film and the sheet prematurely adhere to each other to the point of preventing the expulsion of the air inclusions present between the film and the sheet.

In order to seek to resolve the above-described problem, it has been thought to connect the pre-laminator and the laminator by means of a tunnel that is nearly thermally isolated from the environment outside the pre-laminator and the laminator, and comprising at least one conveyor belt on which the pre-laminated board can be laid down for the conveyance thereof from an outlet mouth of the pre-laminator to an inlet mouth of the laminator.

However, the abovementioned solution is not very satisfactory since, even if it allows limiting the increase of temperature sustained by the board at the outlet of the pre-laminator, a heating is still verified of the photosensitive film which sometimes gives rise to a premature adhesion between the film and the sheet opposed thereto.

Objects of the invention

Object of the present invention is to overcome the aforesaid drawbacks and to indicate a device capable of preventing a premature adhesion, in a pre- laminated printed circuit board, between a photosensitive film and a sheet on which the film is extended, during the conveyance of the board from a pre- laminator to a laminator.

Summary of the invention

The subject of the present invention is a device for conditioning a pre-laminated printed circuit board during the travel from an outlet mouth of a pre-laminator to an inlet mouth of a laminator, said device comprising a system for cooling said pre-laminated printed circuit board and a module for moving said pre-laminated board between said outlet and inlet mouths, in which, according to the invention, the cooling system comprises:

· means suitable for thermally conditioning a gaseous fluid (indicated hereinbe- low in the present description with the expression "conditioning means"); • means communicating with the conditioning means and suitable for introducing the conditioned fluid into an environment traversable by the pre-laminated board, said introduction at least partially occurring at a substantially laminar condition. The latter means will be indicated hereinbelow in the present description with the expression "introduction means".

Incidentally, the environment traversable by the pre-laminated board is, by way of example, an environment interposed between an outlet mouth of a pre- laminator and an inlet mouth of a laminator, i.e. an environment traversable by the board during the conveyance of the latter from the pre-laminator to the laminator. In particular, the device, subject of the invention, allows maintaining the environment traversable by the pre-laminated board and consequently the board itself at a suitably low temperature, so as to prevent a premature adhesion between the photosensitive film and the sheet opposed thereto.

The expression "substantially laminar" indicates a flow substantially lacking turbulence.

Given that the conditioned fluid is in substantially laminar motion, it will hit the board without at all compressing the photosensitive film against the sheet, and without determining any relative sliding between the film and sheet.

Advantageously, the system, subject of the invention, can be installed, by way of example, at any one connection tunnel between a pre-laminator and a laminator, in a manner so as to thermally condition the air inside said tunnel. Further innovative characteristics of the present invention are described in the dependent claims.

According to one aspect of the invention, the introduction means comprise filtering means suitable for at least partially removing, from the conditioned fluid, sol- id and liquid particles possibly present therein.

According to another aspect of the invention, the filtering means comprise a filter of HEPA type having a filtration effectiveness preferably comprised between 85% and 99.99% (with reference to the total capacity).

Incidentally, the filtration effectiveness of a HEPA filter is calculated by making reference to the filtration capacity of particles having a (equivalent spherical) diameter of 0.3 pm.

Advantageously, given that the introduction means are equipped with a HEPA filter, the conditioned fluid that hits the pre-laminated board substantially lacks powders that could adhere to the photosensitive film and compromise the sub- sequent photo-etching process.

According to another aspect of the invention, the cooling system comprises:

• means for detecting the temperature of the conditioned fluid at the outlet of the introduction means;

• first means for controlling the conditioner means, the first control means be- ing connected to the detector means for the reception, from the latter, of the detected temperature, the first control means being suitable for commanding the actuation of the conditioner means in a manner so as to bring and maintain the temperature of the conditioned fluid at the outlet of the introduction means to/at a value that is as close as possible to a predefined temperature. According to another aspect of the invention, the gaseous fluid is ambient air. Still according to the invention, a module is present for moving a pre-laminated printed circuit board from an outlet mouth of a pre-laminator to an inlet mouth of a laminator, said module comprising:

• means suitable for conveying the pre-laminated board between said outlet and inlet mouths. These means will be indicated hereinbelow in the present description with the expression "conveyor means";

In other words, according to the invention, the abovementioned cooling system is associated with a movement module for conveying the pre-laminated board through an environment in which the conditioned fluid can be introduced, by the introduction means, said environment being interposed between said outlet and inlet mouths, and, therefore, traversable by the pre-laminated board by means of the conveyor means.

According to one aspect of the invention, the introduction means comprise at least one wall, preferably flat, through which the conditioned fluid is introduced into said environment, preferably in a direction substantially perpendicular to said wall, the conveyor means being suitable for conveying the pre-laminated board, maintaining the latter preferably parallel to said wall.

Advantageously, the conditioned fluid hits the pre-laminated board in a direction nearly orthogonal thereto.

According to another aspect of the invention, the movement module comprises:

• first means for moving the introduction means, the first movement means be- ing suitable for moving the introduction means between said outlet and inlet mouths;

• second means for controlling the first movement means, the second control means being suitable for commanding the actuation of the first movement means in a manner such that the pre-laminated board and said wall of the in- troduction means are always opposite each other during the conveyance of the pre-laminated board between said outlet and inlet mouths.

This ensures that the pre-laminated board is always hit by a flow of conditioned fluid during the conveyance from the pre-laminator to the laminator.

According to another aspect of the invention, the introduction means comprise at least one wall through which the conditioned fluid is introduced into said environment, preferably in a direction nearly transverse to said wall, said wall preferably being extended from the outlet mouth of the pre-laminator to the inlet mouth of the laminator.

Advantageously, the conditioned fluid fully hits the path that can be traveled by the pre-laminated board during the conveyance thereof from the pre-laminator to the laminator. This ensures that the pre-laminated board is always hit by a flow of conditioned fluid during the conveyance from the pre-laminator to the laminator.

Incidentally, in an equivalent manner, the introduction means could comprise a plurality of filtering walls which, in their entirety, are extended from the outlet mouth of the pre-laminator to the inlet mouth of the laminator.

According to another aspect of the invention, the conveyor module comprises second means for moving the introduction means, the second movement means being suitable for moving the introduction means in a direction preferably perpendicular to said wall (and hence also to the pre-laminated board during the conveyance thereof from the outlet mouth of the pre-laminator to the inlet mouth of the laminator).

Advantageously, due to the presence of the second movement means, it is possible to adjust the distance between the introduction means (and said wall therewith) and the pre-laminated board, in a direction orthogonal to the movement of the latter from the pre-laminator to the laminator. The smaller the dis- tance between the introduction means and the pre-laminated board, the greater the possibility that the flow of conditioned fluid is still laminar at the instant when it hits the board.

According to another aspect of the invention, the cooling system comprises means suitable for thermally isolating the environment interposed between said outlet and inlet mouths, from an environment outside the movement module. According to another aspect of the invention, the conditioning means communicate with said thermally isolated environment in a manner so as to draw the fluid to be conditioned directly from said thermally isolated environment.

Advantageously, the fluid present in the thermally isolated environment is recy- cled. Hence, less effort is required by the conditioning means to maintain the temperature of the fluid at the outlet of the introduction means at a value that is as close as possible to a predefined temperature. In addition, the filtration of the fluid by the filtering means is more effective since, except for an initial transitory phase, the fluid entering into the filtering means has already been at least par- tially filtered.

According to another aspect of the invention, the thermal isolation means comprise a tunnel that is extended from the outlet mouth of the pre-laminator to the inlet mouth of the laminator.

According to another aspect of the invention, the conveyor means comprise a conveyor belt which is extended from the outlet mouth of the pre-laminator to the inlet mouth of the laminator.

Brief description of the figures

Further objects and advantages of the present invention will be clearer from the following detailed description of an embodiment thereof and from the enclosed drawings, given as merely exemplifying and non-limiting, in which:

- figure 1 schematically shows a device for conditioning a pre-laminated print- ed circuit board between a pre-laminator and a laminator according to the present invention, the device comprising a system for cooling the pre- laminated board and a movement module, it too according to the present invention;

- figure 2 schematically shows a variant of the movement module of figure 1. Detailed description of several preferred embodiments of the invention

Hereinbelow in the present description, a figure can also be illustrated with reference to elements not expressly indicated in that figure but in other figures. The scale and proportions of the various depicted elements do not necessarily correspond to the actual scale and proportions.

Figure 1 shows a module 1 for conveying a pre-laminated printed circuit board 2 from an outlet mouth 3 of a pre-laminator 4 to an inlet mouth 5 of a laminator 6. The module 1 is therefore interposed between the pre-laminator 4 and the laminator 6. As is visible in figure 1 , the board 2 comprises a sheet 7, of multilayer type; on one wall of such sheet (the upper wall, in the figure), a photosen- sitive film 8 has been extended for the obtainment of the printed circuit board. The module 1 comprises a conveyor belt 9 which, extended from the outlet mouth 3 to the inlet mouth 5, traverses the module 1 over the entire length thereof. The board 2 rests on the belt 9 for the conveyance thereof from the pre- laminator 4 to the laminator 6. By way of example, the belt 9 is arranged hori- zontally.

The module 1 also comprises a plurality of walls connected to each other, and to the pre-laminator 4 and laminator 6 to form a tunnel 10 that is extended from the outlet mouth 3 to the inlet mouth 5. The tunnel 10 therefore delimits, together with the pre-laminator 4 and the laminator 6, an environment 1 1 traversed by the belt 9 and interposed between the outlet mouth 3 and the inlet mouth 5. The environment 1 1 is therefore traversable by the board 2 by means of the belt 9. Preferably, the walls of the tunnel 10 and the connections thereof are made in a manner so as to thermally isolate the environment 1 1 from an environment outside the tunnel 10, outside the pre-laminator 4 and the lamina- tor 6.

Associated with the module 1 , there is also a system 20 for cooling the board 2 in transit between the pre-laminator 4 and the laminator 6, rested on the belt 9. The cooling system 20 comprises:

• a conditioner 21 suitable for thermally conditioning a gaseous fluid by bringing it to a temperature preferably comprised between 5°C and 15 °C, and still more preferably between 8 °C and 12 °C. By way of example, the condition- able fluid is ambient air drawn by the conditioner 21 from the environment outside the tunnel 10, outside the pre-laminator 4 and the laminator 6. The conditioner 21 is preferably housed outside the tunnel 10;

• a distributor 22 communicating both with the conditioner 21 , and with the tunnel 10, and suitable for introducing the conditioned air exiting from the conditioner 21 into the environment 1 1 inside the tunnel 10. In particular, the distributor 22 comprises, by way of example:

- a collector 23 communicating with the conditioner 21 for collecting the conditioned air exiting from the latter. The collector 23 is preferably housed, together with the conditioner 21 , outside the tunnel 10;

- at least one duct 24 communicating, at one end, with the collector 23 and traversing at least one wall of the tunnel 10 in order to conduct the conditioned air collected in the collector 23 inside the tunnel 10;

- a diffuser 25 housed within the tunnel 10 and communicating with the duct 24 at a second end thereof opposite the first end. The diffuser 25 intro- duces, into the environment 11 , the conditioned air coming from the duct

24. This introduction at least partially occurs at a substantially laminar condition. • a filter 26 housed, by way of example, inside the diffuser 25 in order to at least partially remove, from the conditioned air, solid and liquid particles possibly present therein, before the introduction of the conditioned air into the environment 11. The filter 26 is for example a filter of HEPA type having a fil- tration efficiency preferably comprised between 85% and 99.99% (with reference to the total capacity);

• a device 27 suitable for detecting the temperature of the conditioned air at the outlet of the diffuser 25. The device 27 is, by way of example, a thermocouple;

· a first control device 28 connected to the conditioner 21 for commanding the actuation thereof. The device 28 is also connected to the thermocouple 27 for the reception, from the latter, of the detected temperature of the conditioned air. The control device 28 commands the actuation of the conditioner 21 in a manner so as to bring and maintain the temperature of the conditioned air at the outlet of the diffuser 25 to/at a value that is as close as possible to a predefined temperature, preferably comprised, as mentioned above, between 5 °C and 15 °C, and still more preferably between 8 °C and 12 °C.

The diffuser 25 comprises a wall 29, preferably flat, through which the conditioned air exits from the diffuser 25 and enters into the environment 11 , prefera- bly flowing in a direction nearly orthogonal to the wall 29. The thermocouple 27 is preferably connected to the diffuser 25 in proximity to the wall 29. The belt 9 and the diffuser 25 are housed within the tunnel 10 preferably in a manner such that the wall 29 and the belt 9 are opposite each other, and still more preferably in a manner such that the wall 29 and the board 2, when conveyed by the belt 9, are mutually parallel. As is visible in figure 1 , the distance between the outlet mouth 3 and the inlet mouth 5 is greater than the size of the wall 29 in a direction that is extended from the pre-laminator 4 to the laminator 6.

The conveyor module 1 comprises a first linear actuator 30 sustained by the frame of the laminator 6. By way of example, the linear actuator 30 is a double- acting pneumatic cylinder comprising a translating stem 31 integrally connected, at one end, to the collector 23 of the distributor 22. By means of the cylinder 30, the distributor 22 is translatable along the tunnel 10 between the outlet mouth 3 and the inlet mouth 5, maintaining the wall 29 of the diffuser 25 opposite the belt 9.

The conveyor module 1 also comprises a second control device (not visible in the figure) connected to the cylinder 30 for commanding the actuation thereof. The second control device is also connected to an apparatus (not visible in the figure) suitable for detecting the presence of the board 2 on the belt 9 and the position of the same in the travel from the outlet mouth 3 to the inlet mouth 5. The second control device commands the actuation of the cylinder 30 in a manner so as to make the distributor 22 translate during the conveyance of the board 2 by the belt 9, such that the wall 29 and the board 2 are always opposite each other during the transit of the board 2 between the mouths 3 and 5.

The board 2 is therefore hit by a flow of conditioned air for the entire passage from the pre-laminator 4 to the laminator 6. The conditioned air maintains the board 2 at a suitably low temperature such to prevent the film 8 and the sheet 7 from mutually adhering before the entrance of the board 2 in the laminator 6. Given that the flow of conditioned air is preferably directed orthogonal to the wall 29 (i.e. vertical in the figure) and given that the latter is preferably arranged parallel to the board 2, the flow of conditioned air hits the board 2 in a direction preferably orthogonal thereto. In addition, given that the flow is preferably at a substantially laminar condition, the flow of conditioned air cannot determine any relative (undesired) sliding between the film 8 and the sheet 7. Due to the presence of the filter 26, the conditioned air that hits the board 2 substantially lacks powders that could adhere to the film 8 and compromise the subsequent photo- etching process.

The conveyor module 1 comprises a second linear actuator 32 preferably supported by the collector 23. By way of example, the linear actuator 32 is a double-acting pneumatic cylinder comprising a translating stem 33 integrally connected, at one end, to the diffuser 25. By means of the cylinder 30, the diffuser 25 is translatable, within the tunnel 10, in a direction perpendicular to that of the wall 29 (i.e. in a direction transverse to that of the board 2 during the advancement of the latter from the pre-laminator 4 to the laminator 6). Due to the presence of the cylinder 32, it is possible to adjust the distance between the diffuser 25 (and the wall 29 therewith) and the board 2. The smaller the distance between the same, the greater the probability that the flow of conditioned air is still laminar at the instant in which it hits the board 2. Given that the diffuser 25 is translatable with respect to the collector 23, the duct 24 is of flexible type.

In an alternative embodiment of the module 1 not shown in the figures, the conditioner 21, rather than drawing the air to be conditioned from the environment outside the tunnel 10, outside the pre-laminator 4 and the laminator 6, draws the air from inside the tunnel 10, i.e. from the environment 11. The air present in the environment 11 is then recycled. Therefore, less effort is required by the conditioner 21 for maintaining the temperature of the conditioned air at the outlet of the diffuser 25 at a value that is as close as possible to the predefined temperature. In addition, the filtration of the air by the filter 26 is more effective since, excluding a transitory initial phase, the air entering into the filter 26 has already been at least partially filtered.

Figure 2 shows a conveyor module 40 that is differentiated from the module 1 of figure 1 due to the fact that the wall 41 of the diffuser 42 of the cooling system 43 is extended from the outlet mouth 3 to the inlet mouth 5. The conditioned air therefore hits the entire passage traveled by the board 2 during the movement thereof from the pre-laminator 4 to the laminator 6. This makes the presence of the cylinder 30 superfluous since the board 2 is hit by a flow of conditioned air at every instant of its movement from the pre-laminator 4 to the laminator 6.

On the basis of the description provided for a preferred embodiment, it is obvious that several changes can be introduced by the man skilled in the art without departing from the scope of the invention as defined by the following claims.

Claims

C L A I M S

1. Device (1 , 40) for conditioning a pre-laminated printed circuit board (2) during the travel from an outlet mouth (3) of a pre-laminator (4) to an inlet mouth (5) of a laminator (6), said device (1 , 40) comprising:

· a system (20) for cooling said pre-laminated printed circuit board (2),

• module (1 , 40) for moving said pre-laminated board (2) between said outlet mouth (3) and said inlet mouth (5).

2. Device according to claim 1 , characterized in that said cooling system (20) comprises:

· means (21 ) for the thermal conditioning of a gaseous fluid;

• means (22, 23, 24, 25, 29, 41 , 42, 43) for the introduction, in conditions that are at least partially substantially laminar, of said conditioned fluid into an environment (11 ) traversable by said board (2),

3. Device according to claim 2, characterized in that said introduction means (22, 23, 24, 25, 29, 41 , 42, 43) comprise at least one wall (29, 41 ) through which said conditioned fluid is introduced into said environment (11 ) in a direction perpendicular to said wall (29, 41 ).

4. Device according to claim 2, characterized in that said introduction means (22, 23, 24, 25, 29, 41 , 42, 43) comprise filtering means (26) suitable for at least partially removing, from said conditioned fluid, solid and liquid particles possibly present in said fluid.

5. Device according to claim 4, characterized in that said filtering means (26) comprise a filter of HEPA type.

6. Device according to claim 1 , characterized in that said cooling system com- prises:

• means (27) for detecting the temperature of said conditioned fluid at the outlet of said introduction means (22, 23, 24, 25, 29, 41 , 42, 43);

• first means (28) for controlling said conditioner means (21 ), said first control means (28) being connected to said detector means (27) for the re- ception, from the latter, of the detected temperature, said first control means (28) being suitable for commanding the actuation of said conditioner means (21 ) in a manner so as to bring and maintain the tempera- ture of said conditioned fluid at the outlet of said introduction means (22, 23, 24, 25, 29, 41 , 42, 43) to/at a value substantially equal to that of a predefined temperature.

7. Device according to claim 1 , characterized in that said cooling system comprises means (10) suitable for thermally isolating said environment (11 ) from an environment outside said module (1 , 40).

8. Device according to claim 1 , characterized in that said conditioning means (21 ) communicate with said environment (11 ) in a manner so as to draw said fluid to be conditioned from said environment (11 ).

9. Device according to claim 1 , characterized in that said module (1 , 40) for moving said pre-laminated board (2) comprises:

• means (9) for conveying said board (2) between said outlet (3) and inlet (5) mouths, said conveyor means (9) being suitable for conveying said board (2), maintaining the latter parallel to said wall (29, 41 );

• first means (30, 31 ) for moving said introduction means (22, 23, 24, 25, 29) between said outlet (3) and inlet (5) mouths;

• second means for controlling said first movement means (30, 31), said second control means being suitable for commanding the actuation of said first movement means (30, 31 ) in a manner such that said board (2) and said wall (29) are always opposite each other during the conveyance of said board (2) between said outlet (3) and inlet (5) mouths.

10. Device according to claim 3, characterized in that said wall (41 ) is extended from said outlet mouth (3) to said inlet mouth (5).

11. Device according to claim 1 , characterized in that it comprises means (32, 33) for moving said cooling system (20) in a direction perpendicular to said pre-laminated board (2).

12. Device according to claim 11 , characterized in that said movement means control the distance between said introduction means (22, 23, 24, 25, 29, 41 , 42, 43) and said wall (29, 41 ).