Glazing with improved sound insulation performance

The integration of a polymer foam plate with periodic perforations and a desiccant within the glazing system addresses the limitations of existing double glazing by improving sound transmission loss and humidity management, resulting in superior acoustic insulation.

FR3146705B1Active Publication Date: 2025-06-06SAINT GOBAIN VITRAGE SA
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Patent Information

Application Number
FR2023002473
Authority / Receiving Office
FR · FR
Patent Type
Patents
Current Assignee / Owner
Filing Date
2023-03-17
Publication Date
2025-06-06
Estimated Expiration
2043-03-17

AI Technical Summary

Technical Problem

Existing double glazing systems suffer from reduced sound transmission loss at frequencies around the 'mass/spring/mass' resonance frequency, and they also struggle with humidity absorption, which affects acoustic insulation performance.

Method used

The use of a glazing system that incorporates a polymer foam plate with periodic perforations, forming a chamber within the cavity, which enhances acoustic insulation by absorbing sound energy through both the perforations and the polymer foam's porous structure, while also incorporating a desiccant to manage humidity.

Benefits of technology

This configuration significantly improves acoustic insulation by absorbing sound energy across a wide frequency range, including low frequencies, and effectively manages humidity, leading to enhanced soundproofing performance.

✦ Generated by Eureka AI based on patent content.

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Abstract

Glazing with improved acoustic insulation performance The invention relates to a glazing (10) comprising at least two glazed walls (7) forming a cavity between them, in which the cavity comprises at least one acoustic insulation device comprising at least one polymer foam plate (3), said at least one polymer foam plate (3) comprising a plurality of perforations (6) arranged periodically and delimiting a chamber (2) arranged in the cavity. Figure for abstract: Fig. 1
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Description

Title of the invention: Glazing with improved acoustic insulation performance Prior art

[0001] The present invention belongs to the general field of the manufacture of glazing. It relates more particularly to an acoustic insulation device configured to improve the acoustic insulation performance of a glazing and, preferably, to limit the presence of humidity between glazed walls of said glazing. It also relates to a glazing comprising at least one such device. The invention finds a particularly advantageous, although in no way limiting, application in the case of building glazing.

[0002] Double glazing consisting of two panes separated by a cavity filled with gas, typically air, is conventionally used in windows and building facades for its thermal and acoustic insulation performance.

[0003] However, the loss of sound transmission caused by such double glazing decreases for frequencies surrounding the so-called "mass / spring / mass" frequency corresponding to the resonance frequency of the double glazing and located in the low frequencies. This phenomenon, called the mass / spring / mass effect, is due to significant variations in pressure in the air cavity at the mass / spring / mass frequency.

[0004] Also, in order to improve the acoustic insulation performance of glazing, different solutions have been developed. For example, document WO 2022 / 234237 relates to a glazing comprising at least two glazed walls forming a cavity between them, in which the cavity comprises at least one device comprising at least one plate, said plate comprising a plurality of perforations arranged periodically and delimiting a chamber arranged in the cavity.

[0005] There is a need to provide another system for improving the acoustic insulation properties of a glazing, particularly in the low frequencies, as well as, preferably, the humidity absorption performance of the latter. Description of the invention

[0006] The present invention aims to overcome all or part of the drawbacks of the prior art, in particular those set out above, by proposing a solution which makes it possible to obtain glazing which is much more effective than those of the solutions of the prior art in terms of acoustic insulation. In advantageous embodiments, the manufacturing method is further simplified.

[0007] Thus, and according to a first aspect, the invention relates to a glazing comprising at least two glazed walls forming a cavity between them, in which the cavity comprises at least one acoustic insulation device comprising at least one polymer foam plate, said at least one polymer foam plate comprising a plurality of perforations arranged periodically and delimiting a chamber arranged in the cavity.

[0008] In particular embodiments, the glazing may further comprise one or more of the following characteristics, taken individually or in all technically possible combinations.

[0009] In embodiments, the acoustic insulation device comprises a profile or box formed from a plurality of polymer foam walls, the chamber being an internal space of the profile or box defined by the walls, and the polymer foam plate comprising the plurality of periodically arranged perforations being one of the walls of the profile or box.

[0010] In embodiments, the acoustic insulation device is a glazing spacer device.

[0011] In embodiments, the acoustic insulation device comprises an interior portion facing the chamber and an exterior portion oriented opposite the interior portion, the average proportion of open cells of the polymeric foam in the interior portion being greater than the proportion of open cells in the exterior portion; and preferably the average proportion of open cells of the polymeric foam in the interior portion is between 30% and 99%.

[0012] In embodiments, the sound insulation device is single-piece.

[0013] In embodiments, the sound insulation device comprises at least at least one rectilinear bar forming said at least one polymer foam plate, associated with a spacing device, the chamber being delimited by the polymer foam plate and by an edge of the glazing.

[0014] In embodiments, the polymeric foam comprises an average proportion of open cells of 30 to 99%, preferably 65 to 98%.

[0015] In embodiments, the polymeric foam is selected from the group consisting of silicone foams, polyurethane foams, polyethylene foams, melamine foams, and combinations thereof.

[0016] In embodiments, the glazing comprises a desiccant in or associated with the sound insulation device.

[0017] In embodiments, the desiccant is integrated into the polymer foam.

[0018] In embodiments, the desiccant is disposed in at least one envelope, which preferably is held inside or outside the chamber.

[0019] In embodiments, said at least one polymer foam plate comprises at least three perforations, preferably at least four perforations.

[0020] In embodiments, the glazing further comprises one or more additional sound insulation devices, each additional sound insulation device comprising a plate comprising a plurality of perforations arranged periodically and delimiting a chamber arranged in the cavity, wherein preferably the periodicities of the perforations of said polymer foam plate and of said plate of each additional sound insulation device are different from each other.

[0021] In embodiments, the plate of each additional acoustic insulation device comprises a polymeric foam.

[0022] In embodiments, the acoustic insulation device is positioned in a peripheral area of ​​the glazing cavity.

[0023] In embodiments, the glazing is building glazing, such as building facade, window or door glazing or interior glazing.

[0024] The invention also relates to an acoustic insulation device comprising at least one polymer foam plate, said plate comprising a plurality of perforations arranged periodically, said device being suitable for the manufacture of glazing as described above.

[0025] The present invention makes it possible to meet the need expressed above. More particularly, it provides a glazing device which is easy and simple to manufacture, relatively light and compact, while making it possible to obtain glazing with improved acoustic insulation.

[0026] This is accomplished by the presence, in the device, of a polymer foam plate comprising a plurality of perforations arranged periodically, said plate allowing the formation of a chamber. Such a device allows a double acoustic effect, which is accomplished by the absorption of sound energy by said chamber and said plurality of perforations, as well as by the absorption of sound energy by said polymer foam. The combination of the presence of said chamber with the presence of perforations on the plate, these perforations being periodic, allows the creation of resonators making it possible to absorb at least a portion of the sound energy in the cavity of the glazing formed by the two glazed walls, which makes it possible to reduce the transmission of sound through the glazing. In particular, the resonators absorb sound energy significantly for frequencies close to their resonance frequency(ies).In addition, the absorption of energy also for the harmonic frequencies of the resonators as well as physical phenomena related to the modification of the properties of the gas cavity of the glazing, due to the presence of the resonators, allow to improve also the acoustic insulation at frequencies higher than the resonant frequencies of the resonators. In addition, the polymer foam of the plate further reinforces the insulation. acoustic by absorbing, by itself, at least part of the sound energy thanks to its porous structure. Thus, the device of the present invention, which integrates the sound absorption capabilities, is easy to manufacture while offering improved sound insulation performance. Brief description of the drawings

[0027] Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the appended drawings which illustrate an exemplary embodiment thereof without any limiting character. In the figures: [Fig.l], [Fig.l] represents on its left part an example of glazing according to the invention and, on its right part, an enlarged schematic and perspective view of an example of device according to the invention in the form of a profile present in this example of glazing (first variant); [Fig.2], [Fig.2] represents a schematic view in longitudinal section of an example of a device according to the invention in the form of a box (second variant); [Fig.3], [Fig.3] represents on its left part another example of glazing according to the invention and, on its right part, an enlarged schematic and perspective view of an example of a device according to the invention in the form of a box present in this example of glazing (second variant); [Fig.4], [Fig.4] represents on its left part another example of glazing according to the invention and, on its right part, an enlarged and perspective schematic view of an example of device according to the invention in the form of a box present in this example of glazing (third variant); [Fig.5], [Fig.5] represents on its left part another example of glazing according to the invention and, on its right part, an enlarged schematic and perspective view of an example of device according to the invention in the form of a bar present in this example of glazing (fourth variant); [Fig.6], [Fig.6] schematically represents, according to a longitudinal sectional view taken in the XZ plane, a particular embodiment of the device of [Fig.1] or [Fig.3]; [Fig.7], [Fig.7] schematically represents, according to a longitudinal sectional view taken in the XZ plane, another particular embodiment of the device of [Fig.1] or [Fig.3].

[0028] Description of embodiments

[0029] The invention is now described in more detail and in a non-limiting manner in the following description.

[0030] The invention relates firstly to an acoustic insulation device for glazing.

[0031] The remainder of the description aims firstly to set out, according to embodiments, aspects of configuration of said device allowing the glazing equipped therewith to provide excellent performance in terms of acoustic insulation.

[0032] The glazing may be any type of glazing comprising at least two glazed walls defining a cavity between them. For the purposes of the present invention, the cavity of a glazing is defined as being the volume between two glazed walls of said glazing.

[0033] The device according to the invention may be or may comprise a spacing device for glazing. By "spacing device" is meant any device making it possible to fix the length of the spacing between the glazed walls of the glazing in which it is intended to be placed.

[0034] Alternatively, the device according to the invention may not be used as a spacing device but be associated with a spacing device.

[0035] The device according to the invention comprises at least one polymer foam plate comprising a plurality of perforations arranged periodically (also called "perforated polymer foam plate" or "perforated plate" hereinafter). By "polymer foam" is meant a material having a porous structure, which is composed of a large number of small air bubbles, called "cells", in a solid polymer matrix.

[0036] The polymer foam plate comprises two main faces opposite each other and carrying the perforations, called in the present text "internal face" (corresponding to the face directed towards the center of the cavity formed between the glazed walls of the glazing) and "external face", which is opposite the internal face.

[0037] For the perforated polymer foam plate, a length can be defined, corresponding to the largest dimension of the plate in the plane of its main faces (also called the “main plane of the plate”), a width, corresponding to the dimension of the plate in a direction perpendicular to the direction of the length of the plate, in the main plane of the plate, and a thickness, corresponding to the dimension of the plate in a direction perpendicular to the main plane of the plate (and therefore corresponding to the dimension of the plate between its two main faces).

[0038] The perforated polymer foam plate is preferably rectangular parallelepiped (i.e. it has a constant length, width and thickness).

[0039] When the device according to the invention is a spacing device, the width of the perforated polymer foam plate preferably determines the length of the spacing between the glass walls (i.e. the thickness of the cavity between the glass walls) of the glazing in which the spacing device is intended to be used. The width of the polymer foam plate may be from 6 to 30 mm, preferably from 10 to 20 mm, for example 16 mm or 20 mm, particularly in embodiments in which the device is a spacer device.

[0040] The thickness of the perforated polymer foam plate is advantageously from 0.1 to 15 mm, more preferably from 0.2 to 1 mm. In particular, the perforated polymer foam plate may have a thickness of 0.1 to 0.2 mm, or from 0.2 to 0.4 mm, or from 0.4 to 0.6 mm, or from 0.6 to 0.8 mm, or from 0.8 to 1 mm, or from 1 to 1.2 mm, or from 1.2 to 1.5 mm, or from 1.5 to 2 mm, or from 2 to 3 mm, or from 3 to 4 mm, or from 4 to 5 mm, or from 5 to 10 mm, or from 10 to 15 mm.

[0041] The polymer foam plate may be manufactured by any method known to those skilled in the art. For example, the polymer foam plate is manufactured by injection molding. A physical and / or chemical expanding agent may be used to achieve expansion of the polymer, for example in the mold. Alternatively, the plate may be manufactured by an extrusion foaming technique.

[0042] The polymer foam of the plate of the invention may be selected from the group consisting of silicone foams, polyurethane foams, polyolefin foams (and in particular polyethylene), melamine foams, and combinations thereof. The polymer foam is preferably a silicone foam or a polyurethane foam.

[0043] The polymer foam of the plate can be characterized by an average porosity greater than or equal to 0.7 and / or an average resistivity to the passage of air ranging from 5,000 to 150,000 Nsm 4. The porosity of the material can be measured using a porosimeter according to the fluid saturation method, by mercury intrusion. The resistivity to the passage of air can be measured according to standard NF EN ISO 9053-1. Such a porous structure of the polymer foam can make it possible to increase the acoustic performance of the device and therefore improve the acoustic insulation of the glazing in which it is placed.

[0044] The polymer foam of the plate may have an average porosity greater than or equal to 0.75, or greater than or equal to 0.8, or greater than or equal to 0.85, or greater than or equal to 0.9, or greater than or equal to 0.95, for example a porosity of 0.7 to 0.75, or 0.75 to 0.8, or 0.8 to 0.85, or 0.85 to 0.90, or 0.90 to 0.95, or 0.95 to 0.99. In a particularly preferred manner, the polymer foam of the plate has an average porosity of 0.7 to 0.99, and more preferably greater than or equal to 0.9. The average air resistance of polymer foam can be from 5,000 to 10,000 Nsm4, or from 10,000 to 20,000 Nsm4, or from 20,000 to 40,000 Nsm 4, or from 40,000 to 60,000 Nsm4, or from 60,000 to 80,000 Nsm4, or from 80,000 to 100,000 Nsm 4, or from 100,000 to 120,000 Nsm 4, or from 120,000 to 140,000 Nsm4, or from 140,000 to 150,000 Nsm 4. Preferably, the polymer foam of the plate has an average resistivity to the passage of air which is from 20,000 to 100,000 Nsm4.

[0045] Advantageously, the polymer foam of the plate may comprise an average proportion of open cells of 30 to 100%, preferably 30 to 99%, more preferably 65 to 98%. The average proportion of open cells may be measured using a microscope. For example, a cross-section of a polymer foam may be examined under a microscope to determine whether each cell is open or closed. The average proportion of open cells is then calculated by dividing the total number of open cells by the total number of cells. The microscope may be, for example, an optical microscope or a scanning electron microscope.Alternatively, the average proportion of open cells can be measured using an ultrasonic tortuosimeter by measuring the characteristic lengths of a polymer foam (e.g., viscous and thermal characteristic lengths) which are then used for the calculation of the porosity of the foam and thus determine the open cell rate.

[0046] The polymer foam of the plate may comprise an average proportion of closed cells of 0 to 70%, preferably of 1 to 70%, more preferably of 2 to 35%. The average proportion of closed cells may be measured in the same way as the average proportion of open cells.

[0047] By "open cells" and "closed cells" is meant, respectively, cells that are interconnected with each other (i.e., there are open passages between the cells), and cells that are isolated from each other (i.e., there are no open passages between the cells). In general, open-cell foams have better sound absorption capacity due to the transmission of sound between the cells, while closed-cell foams have greater stiffness. Of course, the stiffness and sound absorption capacity of polymer foam depend on various factors, such as the density of the foam, the size of the cells, and the chemical composition of the foam.

[0048] In some embodiments, the average proportion of open cells in the polymer foam of the plate may be, for example, greater than or equal to 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or about 100%. When the device is not a spacer device, the average proportion of open cells is preferably about 100%. The average proportion of closed cells in the polymer foam of the plate may be, for example, less than or equal to 70%, 60%, 50%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, 2%, 1%, or about 0%. When the device is not a spacer device, the average proportion of closed cells is preferably about 0%.

[0049] The polymer foam plate comprises a plurality of perforations arranged periodically. By "plurality of perforations" is meant at least two perforations. More particularly, the polymer foam plate may comprise two, or three, or at least three, or four, or at least four, or five, or at least five, or six, or at least six, or seven, or at least seven, or eight, or at least eight, or nine, or at least nine, or ten, or at least ten, perforations arranged periodically. The more perforations the polymer foam plate comprises arranged periodically, the more the acoustic insulation of the glazing in which the device is present is improved. In a particularly preferred manner, the polymer foam plate comprises at least three perforations, more preferably at least four perforations, arranged periodically.

[0050] By "periodically arranged perforations" is meant that said perforations are identical and are present at regular intervals on the polymer foam plate (i.e. the distance between the centers of two adjacent perforations is essentially constant). The perforations are made over the entire thickness of the polymer foam plate (they extend from the internal face of the polymer foam plate to its external face) and put the spaces located on either side of said polymer foam plate into fluid communication (i.e. they allow the circulation of a fluid, and more particularly of a gas, from one space to the other). Advantageously, the periodic perforations are all aligned, more preferably along a longitudinal axis of the polymer foam plate (i.e. along the direction of its length).Even more advantageously, the perforations are arranged along a longitudinal axis of the polymer foam plate located in the middle of the width of the polymer foam plate.

[0051] The perforations can be made according to any method known to those skilled in the art. Depending on the method, the perforations can be made during the extrusion of the device (in-line) or using drilling technology (off-line) by an additional step of the method.

[0052] The perforations may have any suitable shape. In embodiments, they have a cross-section (i.e., in the principal plane of the polymer foam plate) which is circular or substantially circular.

[0053] Advantageously, the perforations of the polymer foam plate are microperforations. By "microperforations" is meant holes whose diameter or maximum dimension (in the main plane of the polymer foam plate) is less than or equal to 8 mm. Preferably, the perforations have a diameter, or a maximum dimension (in the main plane of the polymer foam plate) of 0.2 to 8 mm, more preferably of 0.5 to 8 mm. In embodiments, the diameter or maximum dimension of the perforations may be 0.2 to 0.5 mm, or 0.5 to 1 mm, or 1 to 2 mm, or 2 to 3 mm, or 3 to 4 mm, or 4 to 5 mm, or 5 to 6 mm, or 6 to 7 mm, or 7 to 8 mm.

[0054] In a particularly preferred manner, the periodic perforations are distributed over the entire length of the polymer foam plate. Alternatively, the perforations may be arranged periodically over only a portion of the length of the polymer foam plate, for example over a portion of the polymer foam plate having a length less than or equal to 90%, or less than or equal to 80%, or less than or equal to 70%, or less than or equal to 60%, or less than or equal to 50%, or less than or equal to 40%, or less than or equal to 30%, or less than or equal to 20%, or less than or equal to 10%, of the length of the polymer foam plate.

[0055] For each perforation, a geometric center of said perforation can be defined (hereinafter simply called "center"). The distance between the centers of two adjacent perforations is preferably 5 to 200 mm, more preferably 10 to 110 mm. The distance between the centers of two adjacent periodic perforations may be 5 to 10 mm, or 10 to 20 mm, or 20 to 30 mm, or 30 to 40 mm, or 40 to 50 mm, or 50 to 60 mm, or 60 to 70 mm, or 70 to 80 mm, or 80 to 90 mm, or 90 to 100 mm, or 100 to 110 mm, or 110 to 120 mm, or 120 to 140 mm, or 140 to 160 mm, or 160 to 180 mm, or 180 to 200 mm.

[0056] Advantageously, the open area ratio (i.e. the ratio of the surface area of ​​all the perforations arranged periodically to the total surface area of ​​the polymer foam plate (including the surface area of ​​the perforations)) is from 0.01 to 8%, preferably from 0.05 to 0.8%. The open area ratio can be 0.01 to 0.05%, or 0.05 to 0.1%, or 0.1 to 0.2%, or 0.2 to 0.3%, or 0.3 to 0.4%, or 0.4 to 0.5%, or 0.5 to 0.6%, or 0.6 to 0.7%, or 0.7 to 0.8%, or 0.8 to 0.9%, or 0.9 to 1%, or 1 to 2%, or 2 to 3%, or 3 to 4%, or 4 to 5%, or 5 to 6%, or 6 to 7%, or 7 to 8%.

[0057] The perforated polymer foam plate delimits a chamber, in the device itself or in the glazing in which this device is arranged. The chamber is located inside the cavity of the glazing.

[0058] The thickness of the chamber is preferably from 2 to 200 mm, more preferably from 5 to 50 mm. The thickness of the chamber corresponds to the dimension of the chamber in a direction perpendicular to the main plane of the polymer foam plate. In embodiments, the chamber has a thickness of 2 to 5 mm, or 5 to 10 mm, or 10 to 20 mm, or 20 to 30 mm, or 30 to 40 mm, or 40 to 50 mm, or 50 to 60 mm, or 60 to 70 mm, or 70 to 80 mm, or 80 to 90 mm, or 90 to 100 mm, or 100 to 120 mm, or 120 to 140 mm, or 140 to 160 mm, or 160 to 180 mm, or 180 to 200 mm.

[0059] The sizing and configuration of the polymer foam plate, its perforations and the chamber can be chosen according to the frequency at which the assembly formed by the polymer foam plate and the chamber is desired to resonate. Indeed, the relationship between the resonant frequency / of the perforated polymer foam plate and the thickness of the polymer foam plate, the thickness of the chamber, the spacing between the perforations and the size and distribution of the perforations can be estimated by the formula:

[0060] [Math.l] f = 54000^«^

[0061] In this equation 1, o is the open area ratio (dependent on the size of the perforations and their distribution), L is the thickness of the polymer foam plate in m, D is the thickness of the chamber in m and d is the distance between the centers of two adjacent perforations in m.

[0062] Advantageously, the system consisting of the polymer foam plate and the chamber is configured to resonate at low frequencies. By "low frequencies" is meant sound waves with a frequency of less than 300 Hz. For example, the system consisting of the polymer foam plate and the chamber may be configured to resonate at a frequency of less than or equal to 250 Hz, or less than or equal to 225 Hz, or less than or equal to 200 Hz, or less than or equal to 175 Hz, or less than or equal to 150 Hz. In other embodiments, the system consisting of the polymer foam plate and the chamber may be configured to resonate at a frequency of less than or equal to 400 Hz, or less than or equal to 350 Hz.

[0063] The polymer foam plate preferably comprises a single series of perforations arranged periodically. Alternatively, it may comprise several series of perforations arranged periodically in the polymer foam plate, such as at least two series or at least three series, each series being different from the others (for example, the size of the perforations and / or the distance between the centers of two adjacent perforations may be different in each series). When the polymer foam plate comprises several series of periodic perforations, each series is located in a different portion of the polymer foam plate (depending on its length).The presence of several different series of periodic perforations allows the polymer foam plate and chamber system to resonate at several frequencies, with each portion of the polymer foam plate and chamber assembly that includes a different series of periodic perforations having a different resonant frequency.

[0064] The perforations may be covered by a fabric, in part or, preferably, in full. For example, the fabric may be glued by any suitable means to the polymer foam plate, such as to the inner face of the polymer foam plate. The fabric thus forms a screen against the perforations having a certain resistivity. Without wishing to be bound by a theory, the inventors believe that when sound waves pass through the fabric to enter the chamber, they encounter a resistivity due to the presence of the fabric, which improves the absorption of sound energy and therefore the acoustic insulation of the glazing comprising the device at low, medium and high frequencies. The fabric advantageously has a thickness ranging from 0.1 to 3 mm, preferably from 0.2 to 1 mm. The fabric may be made of any woven natural or synthetic fibers, such as, for example, cotton fibers and / or linen fibers.The fabric preferably has a porosity of 0.07 to 0.99, and more preferably of 0.5 to 0.99, and / or an air resistance of 90,000 to 3,500,000 Nsm 4, more preferably of 300,000 to 3,000,000 Nsm 4. The air resistance and the porosity can be measured in the manner indicated above. The fabric can have a porosity of 0.07 to 0.2, or 0.2 to 0.4, or 0.4 to 0.6, or 0.6 to 0.8, or 0.8 to 0.99. The air resistance of the fabric can be from 90,000 to 300,000 Nsm4, or from 300,000 to 500,000 Nsm4, or from 500,000 to 1,000,000 Nsm4, or from 1,000,000 to 1,500,000 Nsm 4, or from 1,500,000 to 2,000,000 Nsm 4, or from 2,000,000 to 2,500,000 Nsm4, or from 2,500,000 to 3,000,000 Nsm 4, or from 3,000,000 to 3,500,000 Nsm4.

[0065] The interior of the chamber may comprise a gas, and optionally be covered with a fabric as described above.

[0066] Advantageously, the polymer foam plate as described above is a single-piece object. By "single-piece" is meant that the polymer foam plate is an object made of a single piece, without any visible joints or separate parts. For example, the polymer foam plate is manufactured as a single piece by injection molding.

[0067] In certain preferred embodiments, the invention also consists of equipping the acoustic insulation device for glazing with a desiccant configured to absorb moisture. The term "desiccant" conventionally refers to an agent which has the property of drying out the atmosphere in which it is placed, or, in other words, of absorbing all or part of the moisture contained in this atmosphere. The use of such a desiccant is based on a desire to absorb said moisture before it transforms into liquid water. The desiccant may be present in the acoustic insulation device or associated with it.

[0068] The desiccant agent may comprise granules, preferably in a non-agglomerated manner (i.e. in an individualized manner). Said granules are for example made in molecular sieve, in silica gel, in calcium chloride (CaCl2), in sodium sulfate (Na2SO4), in activated carbon, in zeolites of chemical formulation M2 / nO.Al2O3 .xSiO2.yH2O; M can designate Ca, Mg, K, Na. Generally speaking, any material known to those skilled in the art for producing desiccant agents can be used as granules.

[0069] The desiccant may be integrated into the polymer foam board. For example, the desiccant in the form of granules is held in a fixed position in the polymer foam board in a homogeneous manner. This advantageously prevents any release of the granules through the perforations in the polymer foam board. For example, it may be mixed with the polymer before manufacturing the foam.

[0070] Alternatively, the desiccant may be disposed in at least one envelope, which is preferably held inside or outside the chamber. Each envelope may comprise the desiccant in the form of granules as described above. Each envelope may be made of a flexible or rigid material, such as, for example, paper, plastic, polymer or plant or woven fibers. Said envelope may be provided with perforations allowing the granules to absorb moisture. These perforations are typically of diameters smaller than those of the granules so that the latter cannot escape from the envelope containing them.

[0071] The sound insulation device according to the invention may be in the form of a profile or a box and comprise a plurality of polymer foam walls. In this case, the chamber is an internal space of the profile or box delimited by the walls, and the polymer foam plate comprising a plurality of perforations arranged periodically is one of the walls of the profile or box.

[0072] With reference to [Fig.l], according to a first variant, the sound insulation device according to the invention is in the form of a profile, fixed to each of the two glazed walls, and formed of a plurality of polymer foam walls. The chamber may be an internal space of the profile delimited by the walls, and the polymer foam plate comprising a plurality of perforations arranged periodically, as described above, is one of the walls of the profile. By "profile", we mean a hollow tubular structure, the chamber being the internal space of this tubular structure. The profile may be a rectilinear profile. By "rectilinear profile", we mean that the profile is straight in the direction of its length (a longitudinal axis of the profile can therefore be defined). According to this variant, the device is advantageously a spacing device for the glazing.

[0073] In this first variant, what has been described above regarding the polymer foam of the polymer foam plate applies to all of the walls of the device, which are formed from the same material.

[0074] The sound insulation device 1 according to the first variant may comprise an inner portion facing the chamber 2 and an outer portion oriented opposite to the inner portion. The inner portion corresponds to a region of the device which comprises the inner surface of the different walls, which delimits the chamber. The outer portion corresponds to a region of the device which comprises the outer surface of the different walls (opposite the inner surface). What has been referred to above as the inner face of the polymer foam plate constitutes a part of the outer surface of the device. What has been referred to above as the outer face of the polymer foam plate constitutes a part of the inner surface of the device. For example, the outer portion and the inner portion may each extend over approximately half the thickness of the walls.

[0075] Advantageously, in this variant, the average proportion of open cells of the polymer foam in the inner part is greater than the proportion of open cells in the outer part. Advantageously, the average proportion of closed cells of the polymer foam in the outer part is greater than the proportion of closed cells in the inner part. Such a gradient of open cells and closed cells in the device makes it possible to ensure that the device has sufficient mechanical strength to ensure its function as a spacing device, while ensuring effective absorption of sound waves.Preferably, the average proportion of open cells of the polymer foam in the inner part (and in particular on the inner surface) is from 30 to 100%, preferably from 65 to 100%, more preferably from 70 to 100%, more preferably from 80 to 100%, more preferably from 85 to 100%, more preferably from 90 to 100%, more preferably from 95 to 100%. Preferably, the average proportion of closed cells of the polymer foam in the outer part (and in particular on the outer surface) is from 65 to 100%, preferably from 70 to 100%, more preferably from 80 to 100%, more preferably from 85 to 100%, more preferably from 90 to 100%, more preferably from 95 to 100%.

[0076] Alternatively or additionally, the density of the polymer foam in the interior portion may be less than the density of the polymer foam in the exterior portion. Alternatively or additionally, the size of the cells in the interior portion may be greater than the size of the cells in the exterior portion.

[0077] The foam having such a gradient of cells can be obtained by controlled hardening and expansion in a mold according to methods well known to those skilled in the art.

[0078] Referring again to [Fig. 1], in certain embodiments, the profile comprises at least one upper wall 3, one lower wall 4, two side walls 5 defining the chamber 2 of the profile. In the present text, the terms "Upper" and "lower" are used with reference to the orientation of the profile 1 shown on the right-hand side of [Fig.l]. Of course, the profile may have any other possible orientation, such as for example an orientation in which the longitudinal axis of the profile is vertical or an orientation in which the upper wall is below the lower wall (as shown on the left-hand side of [Fig.l]). The profile may have ends open in the longitudinal direction. The chamber of the profile may, however, be closed by sealing the open ends of the profile (for example against the upper wall of another profile, as shown in the figure).

[0079] The upper wall 3 comprises a plurality of perforations 6 arranged periodically. Thus, the profile 1 is also called “perforated profile” in the present text. The perforations 6 are made over the entire thickness of the upper wall and put the chamber 2 of the profile into fluid communication with the environment external to the profile (that is to say they allow the circulation of a fluid, and more particularly of a gas, from the chamber 2 of the profile to the external environment and vice versa).

[0080] In this first variant, the upper wall 3 of the profile corresponds to the polymer foam plate comprising a plurality of perforations arranged periodically of the device described above, and the chamber 2 of the profile corresponds to the chamber delimited by the polymer foam plate described above. Thus, everything described in the present text in relation to the perforated polymer foam plate and in relation to the chamber delimited by the perforated polymer foam plate applies to the upper wall 3 of the profile 1 and to the chamber 2 of the profile, respectively. Similarly, everything described in the present text in relation to the polymer foam applies to the polymer foam walls of the profile 1.

[0081] In this variant, the thickness of the chamber inside the profile 1 is the distance between the upper wall 3 and the lower wall 4 of the profile 1.

[0082] The upper wall 3 of the profile corresponds to the wall intended to face the center of the cavity formed between the glazed walls 7 of the glazing 10, the lower wall 4 corresponds to the wall of the profile 1 intended to be closest to the edge of the glazed walls 7 of the glazing 10, the side walls 5 are intended to be parallel to the glazed walls 7.

[0083] The upper wall 3 and the lower wall 4 of the profile may be connected by two side walls 5 (each of the two side walls 5 connecting a longitudinal edge of the upper wall 3 to a longitudinal edge of the lower wall 4). In other less preferred embodiments, the upper wall 3 and the lower wall 4 may be connected to each other by any number of walls. The upper wall 3 and the lower wall 4 of the profile are preferably connected to each other by two walls transverse sides 8 (each of the two transverse side walls 8 connecting a transverse edge of the upper wall 3 to a transverse edge of the lower wall 4).

[0084] Advantageously, the main plane of the upper wall 3 and the main plane of the lower wall 4 are parallel to each other. Even more advantageously, the main planes of the upper 3 and lower 4 walls are perpendicular to the main planes of the two side walls 5.

[0085] Preferably, the profile 1 according to the invention has a parallelepiped shape, even more preferably a rectangular parallelepiped shape.

[0086] Each of the walls of the profile 1 may independently have a rectangular parallelepiped shape, preferably each of the walls of the profile 1 has a rectangular parallelepiped shape. The thickness of each wall is advantageously from 0.1 to 15 mm, more preferably from 0.2 to 1 mm. In particular, each wall may have a thickness of 0.1 to 0.2 mm, or from 0.2 to 0.4 mm, or from 0.4 to 0.6 mm, or from 0.6 to 0.8 mm, or from 0.8 to 1 mm, or from 1 to 1.2 mm, or from 1.2 to 1.5 mm, or from 1.5 to 2 mm, or from 2 to 3 mm, or from 3 to 4 mm, or from 4 to 5 mm, or from 5 to 10 mm, or from 10 to 15 mm.

[0087] According to a particular example, the upper wall is less thick than the other walls (the lower wall and the side walls).

[0088] Advantageously, the length of the upper wall 3 of the profile 1 is equal to the length of the cavity between the glazed walls 7 of the glazing 10 in which the device is intended to be placed, in the same direction.

[0089] Advantageously, the device is a single-piece device. For example, the device may be manufactured as a single-piece device by injection molding or extrusion.

[0090] The perforations can be made according to any method known to those skilled in the art. Depending on the method, the perforations can be made during the extrusion of the device (in-line) or using drilling technology (off-line) by an additional step of the method.

[0091] Alternatively, the sound insulation device according to the invention may be in the form of a box. By "box" is meant a hollow closed structure, i.e. comprising a cavity or chamber.

[0092] In this second variant, what has been described above regarding the polymer foam of the polymer foam plate applies to all of the walls of the device, which are formed from the same material.

[0093] As in the first variant, the device according to the second variant may comprise an inner part facing the chamber 2 and an outer part oriented opposite to the inner part (as illustrated by [Fig.2]). The average proportion of open cells of the polymer foam in the inner part (and in particular on the inner surface), the average proportion of cells closed polymer foam in the outer part (and in particular on the outer surface), the cell gradient in the foam, the methods for obtaining such a cell gradient, the thickness of each wall are as defined above in relation to the first variant (profile).

[0094] With reference to [Fig.2] and [Fig.3], the box 21 comprises at least one upper wall 23, one lower wall 24, two longitudinal side walls 25 (preferably opposite each other) and two transverse side walls 28 (preferably opposite each other) defining the chamber of the box. By "longitudinal side wall" is meant a side wall parallel to the longitudinal axis of the rectilinear box and by "transverse side wall" is meant a side wall perpendicular to the longitudinal axis of the rectilinear box (located at a longitudinal end of the box). In the present text, the terms "upper" and "lower" are used with reference to the orientation of the box 21 shown on the right part of [Fig.3]. Of course, the box can have any other possible orientation, as for example shown on the left part of [Fig.3].The upper wall 23 of the box corresponds to the wall intended to face the center of the cavity formed between the glazed walls 7 of the glazing 10, the lower wall 24 corresponds to the wall of the box 21 intended to be closest to the edge of the glazed walls 7 of the glazing 10, the longitudinal side walls 25 are intended to be parallel to the glazed walls 7 and the transverse side walls 28 are intended to be perpendicular to the glazed walls 7.

[0095] Advantageously, the length of the upper wall 23 of the box 21 is equal to the length of the cavity between the glazed walls 7 of the glazing 10 in which the device is intended to be placed, in the same direction.

[0096] According to this second variant, the device is (constitutes) advantageously a spacing device.

[0097] The top wall 23 and the bottom wall 24 of the box may be connected by two longitudinal side walls 25 (each of the two longitudinal side walls 25 connecting a longitudinal edge of the top wall 23 to a longitudinal edge of the bottom wall 24). In other less preferred embodiments, the top wall 23 and the bottom wall 24 may be connected to each other by any number of longitudinal walls 25. The top wall 23 and the bottom wall 24 of the box are preferably connected to each other by two transverse side walls 28 (each of the two transverse side walls 28 connecting a transverse edge of the top wall 23 to a transverse edge of the bottom wall 24).

[0098] Advantageously, the main plane of the upper wall 23 and the main plane of the lower wall 24 are parallel to each other. Preferably, the main planes of the longitudinal side walls 25 are parallel to each other. Preferably, the main planes of the transverse side walls 28 are parallel to each other. Even more advantageously, the main planes of the upper 23 and lower 34 walls are perpendicular to the main planes of the two longitudinal side walls 25 and to the main planes of the two transverse side walls 28. In a particularly preferred manner, the box 21 according to the invention has the shape of a parallelepiped, even more preferably the shape of a rectangular parallelepiped.

[0099] Each of the walls of the box 21 can independently have a rectangular parallelepiped shape, preferably each of the walls of the box 21 has a rectangular parallelepiped shape.

[0100] The upper wall 23 or one of the longitudinal side walls 25 (intended not to be in contact with a glazed wall 27 of the glazing 10 when the box is placed in a glazing) comprises a plurality of perforations 26 arranged periodically. Thus, the box 21 according to the invention is also called “perforated (rectilinear) box” in the present text. The perforations 26 are made over the entire thickness of the wall and put the chamber of the box 21 into fluid communication with the environment outside the box 21.

[0101] In this second variant, the wall of the box 21 comprising the periodic perforations 26 corresponds to the polymer foam plate comprising a plurality of perforations arranged periodically of the device described above, and the chamber of the box 21 corresponds to the chamber delimited by the polymer foam plate described above. Thus, everything described in the present text in relation to the perforated polymer foam plate and in relation to the chamber delimited by the perforated polymer foam plate applies to the perforated wall of the box 21 and to the chamber of the box, respectively. Similarly, everything described in the present text in relation to the polymer foam applies to the polymer foam walls of the profile 1.

[0102] The perforations can be made in the same way as for the first variant.

[0103] In this variant, the thickness of the chamber inside the box 21 is the distance between the wall of the box comprising the periodic perforations (the upper wall 23 or one of the longitudinal side walls 25) and the wall opposite this wall.

[0104] Advantageously, the device is a single-piece unit. For example, the device may be manufactured as a single-piece unit by injection molding.

[0105] Alternatively, with reference to [Fig.4], according to a third variant, in a particularly preferred manner, the width of the box 21 is less than the thickness of the cavity between the glazed walls 27 (in the same direction) of the glazing 30 in which it is intended to be placed. Thus, in this variant, the device is preferably not a spacer device, but the device may rather be associated with a spacer device separate from it. Preferably, at least one of the longitudinal side walls 25 (one or both) is not in contact with a glazed wall 27 when the box is placed in a glazing 30.

[0106] The width of the box 21 may be from 1 to 99% of the thickness of the cavity between the glazed walls of the glazing, for example from 1 to 10%, or from 10 to 20%, or from 20 to 30%, or from 30 to 40%, or from 40 to 50%, or from 50 to 60%, or from 60 to 70%, or from 70 to 80%, or from 80 to 90%, or from 90 to 99%, of the thickness of the cavity between the glazed walls 27. The width of the box 21 may be from 5 mm to less than the thickness of the cavity between the glazed walls 27, for example the width of the box 21 may be from 5 mm to 29 mm, or from 5 mm to 19 mm, or from 5 mm to 15 mm.

[0107] The length of the box 21 may be less than or equal to the length of the cavity between the glazed walls 27 of the glazing 30 in which it is intended to be placed, in the same direction. Preferably, it is less than the length of the cavity in the same direction. The length of the box 21 may be from 1 to 100% of the length of the cavity, for example from 1 to 10%, or from 10 to 20%, or from 20 to 30%, or from 30 to 40%, or from 40 to 50%, or from 50 to 60%, or from 60 to 70%, or from 70 to 80%, or from 80 to 90%, or from 90 to 95%, or from 95 to 100%, of the length of the cavity between the glass walls 27. In embodiments, the length of the box 21 may be from 5 cm to the length of the cavity between the glass walls 27 (in the same direction as the length of the box 21).

[0108] In this third variant, the upper wall 23 or one of the longitudinal side walls 25 (intended not to be in contact with a glazed wall 27 of the glazing 30 when the box is placed in a glazing) comprises a plurality of perforations 26 arranged periodically. The perforations 26 are made over the entire thickness of the wall and put the chamber of the box 21 into fluid communication with the environment outside the box 21.

[0109] The perforations can be made in the same way as in the first variant.

[0110] In this third variant, when the box 21 is associated with a spacing device, the box 21 can be placed, for example, on a conventional spacing device. More preferably, the lower wall 24 of the box 21 can rest on the spacing device. The spacing device of this variant can be a conventional spacing device. Advantageously, the spacing device is placed at the edge of the glazed walls 17 in a glazing 20 (between two glazed walls 17). It can be made of a rigid material, for example, of a metallic material, preferably aluminum and / or stainless steel, and / or made of polymer material, and comprising two wings in contact with the respective glass walls, and a connecting part between the two wings ensuring the maintenance of the glass walls with a determined spacing. When the length of the box 21 is less than the length of the cavity between the glass walls, the box 21 can be located in any location in the peripheral zone of the glazing cavity.

[0111] Advantageously, the device according to this variant is a single piece. For example, the device can be manufactured as a single piece by injection molding.

[0112] With reference to [Fig.5], according to a fourth variant, the sound insulation device according to the invention comprises at least one rectilinear bar 11. By “bar” is meant a solid of rectangular parallelepiped shape. The bar comprises a plurality of perforations 16 arranged periodically. Thus, the bar 11 according to the invention is also called “perforated (rectilinear) bar” in the present text.

[0113] In this fourth variant, the bar 11 forms the polymer foam plate comprising a plurality of perforations arranged periodically of the device, as described above, and is associated with a spacer device distinct from it. The chamber 12 is delimited by the polymer foam plate (bar 11) and by the spacer device (not shown in the figure). Thus, everything described in the present text in relation to the perforated polymer foam plate and the chamber delimited by the perforated polymer foam plate applies to the perforated bar 11 and the chamber 12 delimited by the bar 11 and by the spacer device, respectively.

[0114] In this variant, the polymer foam preferably comprises an average proportion of open cells of 30 to 100%, preferably 65 to 100%, more preferably 70 to 100%, more preferably 80 to 100%, more preferably 85 to 100%, more preferably 90 to 100%, more preferably 95 to 100%. In certain embodiments, the proportion of open cells in the polymer foam may be 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, 99% or 100%. The proportion of open cells is preferably 100%.

[0115] The spacing device of this variant may be a conventional spacing device. Advantageously, the spacing device is placed at the edge of the glass walls 17 in a glazing 20 (between two glass walls 17). It may be made of a rigid material, for example, of a metallic material, preferably of aluminum and / or of stainless steel, and / or of a polymer material, and comprise two wings in contact with the respective glass walls, and a connecting part between the two wings ensuring the maintenance of the glass walls with a determined spacing. The perforated bar 11 may be fixed to the spacing device or simply be arranged adjacent to the spacing device.

[0116] In this fourth variant, the thickness of the chamber 12 corresponds to the dimension of the chamber between the perforated bar 11 and the edge of the glazed walls 17.

[0117] Advantageously, the length of the bar 11 is equal to the length of the cavity between the glazed walls 17 of the glazing 20 in which it is intended to be placed, in the same direction.

[0118] We will now describe different embodiments of the glazing device, in which desiccants are present. More particularly, these different embodiments aim to describe different configurations / dispositions / arrangements of said desiccants.

[0119] For the sake of simplicity, the description of these modes is carried out by considering that the glazing device is in accordance with that described above with reference to [Fig.2] and [Fig.3]. Of course, such considerations are not limiting of the invention, and all the modes described below are adaptable without difficulty, according to all technically operative combinations, to the other configurations described previously.

[0120] [Fig.6] schematically represents, according to a longitudinal sectional view taken in the XZ plane, a particular embodiment of the device 21 of [Fig.3].

[0121] As illustrated by [Fig.6], the desiccant in the form of granules 60 is integrated into the walls of the device 21. [Fig.6] shows that the desiccant is integrated into the lower wall 24 and two transverse side walls 28. Of course, the desiccant can also be integrated into the upper wall 23 and / or the longitudinal side walls 25. In the case of a device 1 in the form of a profile, the desiccant can be integrated into the upper wall 3 and / or the side walls 5.

[0122] Such a device in which the desiccant is integrated into the polymer foam walls can be made by injecting the desiccant into the foam cells of the walls.

[0123] This advantageously prevents any release of the granules 60 through the perforations 26 of the upper wall 23.

[0124] [Fig.7] schematically represents, according to a longitudinal sectional view taken in the XZ plane, yet another particular embodiment of the device 21 of [Fig.3].

[0125] As illustrated by [Fig.7], the device 1 comprises a desiccant agent arranged in four envelopes 70. The envelopes 70 can be held in a fixed position inside the chamber 2. The said envelopes 70 can be held in a fixed position by (direct) contact of each of them with the internal wall of the chamber 2, according to any method known to those skilled in the art, for example by using an adhesive.

[0126] Furthermore, the mode of [Fig.7] has been described considering the presence of four envelopes 70. It should however be noted that the number of envelopes does not constitute a limitation of the invention. Thus, nothing excludes considering a single envelope or even two envelopes, three envelopes or more than four envelopes.

[0127] Regardless of the number of envelopes envisaged, the positioning of these within the chamber 2 does not constitute a limitation of the invention either. For example, in the case of the device in the form of a box 21 (eg, second variant and third variant), the envelopes are advantageously in (direct) contact only with the upper wall 23 and the lower wall 24 of the chamber 2, as illustrated by [Fig. 7]. However, the envelopes may also be in (direct) contact with the side walls (transverse and / or longitudinal). In the case of the device comprising a strip 11 forming a polymer foam plate and associated with a spacing device (eg, fourth variant), the envelopes may be in (direct) contact with the perforated strip (perforated polymer foam plate) and the spacing device.The envelopes may also be arranged at opposite ends of the chamber 2 delimited by the perforated bar and by the spacing device. Preferably, the envelopes are arranged so as to leave said perforations 6 free.

[0128] According to other embodiments not illustrated, the sound insulation device according to the invention comprises the desiccant which is held in a fixed position in the chamber and which comprises a plate, called an “absorbent” plate, made of a solid material, such as for example a material such as those mentioned above with reference to the granules of [Fig.6]. The plate is a rigid element with a (substantially) flat surface.

[0129] More particularly, when the device is a profile or a box, the absorbent plate can extend horizontally over the entire interior surface of the lower wall of the sound insulation device, without occupying the entire volume of the chamber. The absorbent plate can be held in a fixed position on the interior surface of the lower wall according to any method known to those skilled in the art, for example by using an adhesive. Alternatively, the absorbent plate can be fixed to the outside of the device, or even be integrated into a wall of the device, for example the lower wall.

[0130] The desiccants have been described so far considering that they were kept in a fixed position in the chamber of the device. These considerations are however not limiting of the invention, the invention also covering other embodiments in which all or part of the desiccants are not fixed. These other embodiments are preferentially implemented when the isolation device acoustic is positioned in the lower part of the glazing, so that desiccant agents not kept in a fixed position cannot escape through the perforations due to the action of gravity.

[0131] According to other embodiments not illustrated, the acoustic insulation device comprises desiccant agents formed by bars made of a solid material meeting, for example, the same characteristics as those described with reference to the absorbent plate.

[0132] Said bars may be held outside the chamber, and positioned in contact with the acoustic insulation device, for example in contact with the internal face of the perforated polymer foam plate, each bar being separated from a neighboring bar by a perforation. Furthermore, each bar may be held in a fixed position according to any method known to those skilled in the art, for example by using an adhesive.

[0133] The number of bars can be for example from 2 to 12, in particular from 4 to 8.

[0134] The device according to the invention can be according to several of the variants described above- above at the same time. Thus, the device according to the invention may comprise both one or more perforated profiles 1 and one or more perforated bars 11; both one or more perforated profiles 1 and one or more perforated boxes 21; both one or more perforated bars 11 and one or more perforated boxes 21; or both one or more perforated profiles 1, one or more perforated bars 11 and one or more perforated boxes 21.

[0135] The device according to the invention may comprise a single perforated polymer foam plate. In particular, the device according to the invention may comprise a single rectilinear profile 1 comprising perforations 6 in its upper wall 3 or a single perforated rectilinear bar 11 or a single perforated rectilinear box 21. However, preferably, the device comprises several perforated polymer foam plates. More particularly, it advantageously comprises several rectilinear profiles 1 each comprising an upper wall 3 comprising perforations 6 arranged periodically and / or several rectilinear bars 11 comprising perforations 16 arranged periodically and / or several rectilinear boxes 21 comprising perforations 26 arranged periodically in one of its walls.When the device comprises several perforated polymer foam plates, for example several perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated boxes 21, said perforated polymer foam plates, perforated rectilinear profiles 1, perforated rectilinear bars 11 and perforated rectilinear boxes 21 may each independently be as described above.

[0136] Preferably, when the device comprises several perforated polymer foam plates, at least some of them are different from each other and they may all be different from each other and / or at least some chambers delimited by said perforated polymer foam plates are different from each other and they may all be different from each other. In particular, when the device comprises several perforated rectilinear profiles 1, preferably at least some of them are different from each other and they may all be different from each other. More particularly, they may have perforations 6 with a different periodicity, i.e. perforations 6 of different size and / or perforations 6 arranged differently in the upper wall 3 (for example the distance between the centers of two adjacent perforations 6 may be different).Alternatively, or additionally, they may have a top wall 3 of different thickness and / or a chamber 2 of different thickness. When the device comprises several perforated bars 11, preferably at least some of them are different from each other and they may all be different from each other. In particular, they may have perforations 16 with a different periodicity, i.e. perforations 16 of different size and / or perforations 16 arranged differently (for example the distance between the centers of two adjacent perforations 16 may be different), and / or have a different thickness. Alternatively, or additionally, at least some chambers 12 may be different from each other and they may all be different from each other, in particular the chambers 12 may have a different thickness.When the device comprises several perforated rectilinear boxes 21, preferably at least some of them are different from each other and they may all be different from each other. More particularly, they may have perforations 26 with a different periodicity, i.e. perforations 26 of different size and / or perforations 26 arranged differently in the wall (for example the distance between the centers of two adjacent perforations 26 may be different). Alternatively, or additionally, they may have a wall comprising perforations of different thickness and / or a chamber of different thickness.Thus, preferably, the perforated polymer foam plates (in particular the perforated rectilinear profiles 1 and / or the perforated rectilinear bars 11 and / or the perforated rectilinear boxes 21) and the chambers which they delimit are such that at least some of the perforated polymer foam plates, or all of them, resonate, with the chambers which they delimit, at different frequencies.

[0137] The device may comprise two or at least two perforated polymer foam plates (for example, two or at least two perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21) (such as described above), or three or at least three perforated polymer foam plates (for example, three or at least three perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21), or four or at least four perforated polymer foam plates (for example, four or at least four perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21), or five or at least five perforated polymer foam plates (for example, five or at least five perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21).Preferably, at least two of the perforated polymer foam plates (e.g., at least two of the perforated profiles 1 and / or perforated bars 11 and / or perforated boxes 21) have perforations with a different periodicity (i.e., the periodicity of the perforations of one polymer foam plate (e.g., of a profile 1 or a bar 11 or a box 21) is different from the periodicity of the perforations of another polymer foam plate (e.g., of another profile 1 or another bar 11 or another box 21), more preferably, at least three of the perforated polymer foam plates (e.g., at least three of the perforated profiles 1 and / or perforated bars 11 and / or perforated boxes 21) have perforations with a different periodicity.

[0138] In a particularly preferred manner, the device according to the invention comprises three perforated polymer foam plates, and more particularly three perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21, or at least three perforated polymer foam plates, more particularly at least three perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21, and more preferably four (or at least four) perforated polymer foam plates, and more particularly four (or at least four) perforated rectilinear profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21.More preferably three or at least three of these polymer foam plates (in particular three or at least three of these profiles 1 and / or bars 11 and / or boxes 21), with the chambers that they delimit, are configured to resonate at different frequencies.

[0139] The sound insulation device according to the invention may further comprise one or more non-perforated plates and / or one or more plates comprising non-periodic perforations. The non-perforated plates and / or the plates comprising non-periodic perforations may be made of polymer foam, and / or metallic material, preferably aluminium and / or stainless steel, and / or polymer material, preferably polyethylene, polycarbonate, polypropylene, polystyrene, polybutadiene, polyisobutylene, polyester, polyurethane, polymethyl methacrylate, polyacrylate, polyamide, polyethylene terephthalate, made of polybutylene terephthalate, acrylonitrile, butadiene styrene, acrylonitrile styrene acrylate, styrene-acrylonitrile copolymer, or a combination thereof, the polymer material optionally being reinforced with glass fibers.

[0140] Preferably, the device comprises as many polymer foam plates (more particularly boxes and / or bars) as the glazed walls of the glazing in which it is intended to be placed comprise sides, for example it comprises four polymer foam plates.

[0141] The polymer foam plates of the device may be disjointed (all or some of them) or may be joined to each other (all or some of them), preferably at their ends. Preferably, when the device according to the invention is a spacer device, all the polymer foam plates of the spacer device are joined so as to form a frame. When the polymer foam plates are joined, they may form a single piece (the polymer foam plates coming for example from a single polymer foam plate folded in one or more places, for example to form the corners of the frame) or may be assembled together by any suitable means, for example by means of staples, glue, clips and / or by interlocking.In particular, when the device comprises profiles 1, these may be disjointed (all or some of them) or may be joined to each other (all or some of them), preferably at their ends. Preferably, all the profiles 1 of the device are joined so as to form a frame. When the profiles 1 are joined, they may form a single piece (the rectilinear boxes coming for example from a single box folded in one or more places, for example to form the corners of the frame) or may be assembled together by any suitable means, for example by the means indicated above. Similarly, when the device comprises rectilinear bars 11, these may be disjointed (all or some of them) or may be joined to each other (all or some of them), preferably at their ends.Preferably, all the bars of the device are joined so as to form a frame. When the bars are joined, they may form a single piece or may be assembled together by any suitable means, for example by the means indicated above. Similarly, when the device comprises boxes 21, these may be disjointed (all or some of them) or may be joined to each other (all or some of them), preferably at their ends. Preferably, all the boxes 21 of the device are joined so as to form a frame. When the boxes 21 are joined, they may be assembled together by any suitable means, for example by the means indicated above.

[0142] When the device comprises several polymer foam plates, the chambers that they delimit (for example the chambers 2 in the profiles 1 of the device and / or the chambers 12 delimited by the rectilinear bars 11 and by the edges of the glazing) can be closed relative to each other (that is to say that they are not directly in fluid communication with each other), for example by the presence of a partition between the chambers, or can be communicating with each other, or some can be closed relative to each other and others communicating with each other.However, when the polymer foam plates of the device belong to perforated rectilinear boxes 21, the chambers which they delimit, that is to say the chambers inside said boxes 21, are closed with respect to each other (that is to say, they are not directly in fluid communication with each other).

[0143] The invention also relates to glazing comprising a device as described above.

[0144] The glazing according to the invention comprises at least two glazed walls. Advantageously, the glazed walls are parallel or essentially parallel to each other.

[0145] In embodiments, the glazing according to the invention may comprise exactly two glazed walls (it is then called “double glazing”), or exactly three glazed walls (it is then called “triple glazing”), or at least three glazed walls, for example four glazed walls (it is then called “quadruple glazing”).

[0146] For the purposes of the present invention, a “glazed wall” means any structure comprising (or consisting of) at least one glass sheet or a glazed assembly. By “glazed assembly” is meant a multi-layer glazed element of which at least one layer is a glass sheet. Thus, the glazed walls may for example independently comprise a single glass sheet or a glazed assembly, for example consisting of laminated glazing (as described in more detail below).

[0147] The glass sheet can be made of organic or mineral glass. It can be made of tempered glass.

[0148] The glazed walls (or one of the glazed walls) may comprise (or consist of) a glazed assembly comprising at least one glass sheet which may be as described above. The glazed assembly is preferably a laminated glazing unit. By "laminated glazing" is meant at least two glass sheets between which is inserted at least one interlayer film generally made of viscoelastic plastic material. The interlayer film made of viscoelastic plastic material may comprise one or more layers of a viscoelastic polymer such as poly(vinyl butyral) (PVB) or an ethylene-vinyl acetate copolymer (EVA), or ethylene copolymer (corresponding to the definition of an ionomer), more preferably PVB. The interlayer film may be made of standard PVB or acoustic PVB (such as PVB single-layer or three-layer acoustic). Acoustic PVB is generally made up of three layers: two outer layers of standard PVB and an inner layer of PVB with added plasticizer to make it less rigid than the outer layers. The use of glazed walls comprising laminated glazing improves the acoustic insulation of the glazing, the acoustic insulation being further increased when the interlayer film is made of acoustic PVB.

[0149] Each glazed wall comprises two main faces opposite each other corresponding to the faces of the glazed wall having the largest surface areas. Advantageously, the glazed walls independently have a thickness (between their two main faces) greater than or equal to 1.6 mm, for example a thickness of 1.6 to 24 mm, preferably 2 to 12 mm, more preferably 4 to 10 mm, for example 4 or 6 mm. The glazed walls of the glazing according to the invention may all have the same thickness or have different thicknesses. The greater the thickness and / or the higher the density of the glazed walls, the greater the acoustic insulation will be. In addition, the thicker the glazed walls, the lower the mass / spring / mass frequency of the glazing will be.

[0150] Preferably, all the glazed walls of the glazing have an identical height and width. The glazing according to the invention can have any possible shape, and preferably has a quadrilateral shape, in particular a rectangular or essentially rectangular shape. Alternatively, the glazing can have a circular, or essentially circular, shape, or an elliptical, or essentially elliptical shape, or a trapezoidal or essentially trapezoidal shape.

[0151] The glazed walls define a cavity between them. Each of the glazed walls defining the cavity comprises an inner face corresponding to the main face of the glazed wall facing the cavity in question and an outer face corresponding to the second main face of the glazed wall, i.e. corresponding to the main face of the glazed wall opposite the face facing the cavity.

[0152] Advantageously, the device according to the invention is positioned in the cavity of the glazing, more particularly in a peripheral zone of the cavity of the glazing. By "peripheral zone of the cavity" is meant a zone of the cavity adjacent to the edges of the glazed walls and preferably of width (i.e. in a direction orthogonal to the edge of the glazed walls, in the plane of the glazed walls) less than or equal to 20 cm, more preferably less than or equal to 10 cm, more preferably less than or equal to 5 cm.

[0153] Preferably, one or more perforated polymer foam plates of the device according to the invention are each parallel to an edge of the glass walls.

[0154] In a particularly preferred manner, the device is placed in the cavity of the glazing so that the chamber delimited by the perforated polymer foam plate is in fluid communication with the glazing cavity formed between the glazed walls via the perforations of the polymer foam plate. Thus, preferably, when the device comprises at least one perforated profile 1, it is placed in the glazing cavity so that the upper wall 3 of the profile(s) 1 faces the inside of the glazing cavity, the lower wall 4 of the profile(s) 1 facing the outside and the edges of the glazing. Thus, the chamber 2 of the perforated profile(s) 1 is in fluid communication with the glazing cavity via the perforations 6 present in the upper wall 3 of said profiles 1 (i.e. a fluid, and preferably a gas, can circulate from the glazing cavity to the inside of the chamber 2 of the profiles 1, and vice versa).When the device comprises at least one perforated bar 11, it is placed in the glazing cavity so that the wall comprising the periodic perforations 16 faces the inside of the glazing cavity. When the device comprises at least one perforated box 21, it is placed in the glazing cavity so that the wall comprising the periodic perforations 26 either faces the center of the glazing cavity or faces a glazed wall without being in contact with it.

[0155] When the device is a spacer device, the two glass walls are fixed to the spacer device.

[0156] More preferably, when the spacing device comprises at least one perforated profile 1, the two glazed walls are fixed to the side walls 5 of the profile(s) 1 of the spacing device, even more preferably their inner face is each fixed to a side wall 5 of the profile(s) 1 of the spacing device. When the spacing device comprises at least one perforated box 21, the two glazed walls are fixed to the side walls 25 of the box(es) 21 of the spacing device, even more preferably their inner face is each fixed to a longitudinal side wall 25 of the box(es) 21 of the spacing device.

[0157] When the device comprises at least one perforated bar 11, the two glazed walls are preferably fixed to lateral faces opposite each other of the bar 11. Advantageously, the glazed walls are attached to the device according to the invention by gluing, for example by an adhesive, such as a polyisobutylene (PIB)-based adhesive, by a silicone sealant or by a double-sided adhesive tape.

[0158] A seal may also be present, preferably arranged on the external face of the device (i.e. the face of the device closest to the edge of the glass walls), which is preferably the external face of the lower wall 4 of the profile(s) 1 (when the device comprises at least one perforated profile 1). More preferably, the seal extends from this external face to the edge of the glass walls. This seal may be formed from a mastic (called “mastic of sealing”) based on polyurethane, polysulfide and / or silicone. However, when the device comprises a perforated strip 11, preferably no sealing gasket is present on said strip.

[0159] When the device according to the invention is a spacing device, or when the device is not a spacing device but associated with a spacing device, the spacing device makes it possible to fix the length of the spacing between the glass walls. The length of this spacing (i.e. the thickness of the cavity between the glass walls) may be from 6 to 30 mm, preferably from 10 to 20 mm, for example 16 mm.

[0160] Preferably, the cavity of the glazing (between the glazed walls) comprises a gas. The gas may be air and / or carbon dioxide, and / or argon, and / or krypton and / or xenon. The use of argon, krypton or xenon, in addition to or instead of air, makes it possible to improve the thermal insulation of the glazing.

[0161] The glazing according to the invention may be totally opaque, totally transparent, or partly opaque and partly transparent. Preferably, the glazing is at least partly transparent.

[0162] One (or more) of the glazed walls may be tinted in the thickness over all or part of its surface. One (or more) of the glazed walls may be wholly or partly covered with an opaque coating, for example, a paint and / or an enamel. The opaque coating may be present on the inner face of the glazed wall, or on its outer face, or on both faces, preferably it covers the inner face of the glazed wall. In embodiments, only one of the glazed walls of the glazing is covered with an opaque coating. This glazed wall is advantageously the glazed wall intended to be the outermost glazed wall of the glazing when the latter is used in a facade or exterior window of a building.

[0163] In embodiments, the glazed walls of the glazing, or at least one of the glazed walls, may have undergone a treatment to improve the thermal insulation of the glazing. In particular, the glazed wall(s) may comprise one (or more) insulating layer(s) such as an insulating layer based on metal and / or metal oxide, on one or more of their main faces, preferably on the inner face. When the glazed wall is also covered with an opaque coating (such as an enamel and / or a paint), an insulating layer compatible with the opaque coating is preferably used. Alternatively, the insulating layer and the opaque coating may be arranged on different faces of the glazed wall (for example, the insulating layer may be on the inner face and the opaque coating on the outer face).Alternatively, when at least one of the glass walls is a glass assembly, the insulating layer may be interposed in the glass assembly, for example between a layer of PVB and a sheet of glass.

[0164] Advantageously, at least one of the perforated polymer foam plates of the device and the chamber that it delimits are such that the assembly consisting of said perforated polymer foam plate and said chamber resonates at the so-called “mass / spring / mass” frequency of the glazing (for example, at least one of the profiles 1 of the device comprising on its upper wall 3 perforations 6 arranged periodically is such that it resonates at the mass / spring / mass frequency of the glazing and / or at least one of the bars 11 comprising perforations 16 arranged periodically and the chamber 12 that it delimits are such that they resonate at the mass / spring / mass frequency of the glazing and / or at least one of the boxes 21 comprising perforations 26 arranged periodically is such that it resonates at the mass / spring / mass frequency of the glazing).The presence in the glazing according to the invention of polymer foam plates and chambers configured to resonate at the mass / spring / mass frequency of the glazing or at a frequency close to this frequency makes it possible to increase the loss of sound transmission at frequencies close to the mass / spring / mass frequency of the glazing but also at frequencies higher than the mass / spring / mass frequency.

[0165] The mass / spring / mass frequency fmsm of the glazing can be determined by the following formula:

[0166] [Math.2] | ,,,,,^............i 2-^ g /

[0167] In equation 2, p0 is the density of the air in kg / m3, c0 is the speed of sound in the air cavity in m / s, d is the thickness of the air cavity between the two glass walls in m and msi and ms2 are respectively the masses per unit area of ​​the first and second glass walls in kg / m2.

[0168] Preferably, at least one of the perforated polymer foam plates of the device and the chamber that it delimits (more particularly at least one of the profiles 1 of the device comprising on its upper wall 3 perforations 6 arranged periodically and / or at least one of the bars 11 of the device comprising perforations 16 arranged periodically and the chamber 12 that it delimits and / or at least one of the boxes 21 of the device comprising perforations 26 arranged periodically) are configured to resonate at a frequency corresponding to a third of an octave lower than the mass / spring / mass frequency of the glazing, or at a frequency close to it. This makes it possible to increase the loss of sound transmission at frequencies close to this frequency.

[0169] Preferably, at least one of the perforated polymer foam plates of the device and the chamber that it delimits (more particularly at least one of the profiles 1 of the device comprising on its upper wall 3 perforations 6 arranged periodically and / or at least one of the bars 11 of the device comprising perforations 16 arranged periodically and the chamber 12 that it delimits and / or at least one of the boxes 21 of the device comprising perforations 26 arranged periodically) are configured to resonate at a frequency corresponding to a third of an octave higher than the mass / spring / mass frequency of the glazing, or at a frequency close to it. This makes it possible to increase the sound transmission loss at frequencies close to this frequency.

[0170] The presence, in the glazing, of a device comprising at least two perforated polymer foam plates delimiting a chamber (in particular at least two perforated profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21) of which at least one polymer foam plate forms with the chamber that it delimits a system configured to resonate at the mass / spring / mass frequency of the glazing and at least one other polymer foam plate forms with the chamber that it delimits a system configured to resonate at a third of an octave higher or lower than the mass / spring / mass frequency of the glazing,and preferably at least three perforated polymer foam plates delimiting a chamber (in particular at least three perforated profiles 1 and / or perforated rectilinear bars 11 and / or perforated rectilinear boxes 21) of which at least one polymer foam plate forms with the chamber that it delimits a system configured to resonate at the mass / spring / mass frequency of the glazing, at least one other polymer foam plate forms with the chamber that it delimits a system configured to resonate at a third of an octave higher than the mass / spring / mass frequency of the glazing and at least one other polymer foam plate forms with the chamber that it delimits a system configured to resonate at a third of an octave lower than the mass / spring / mass frequency of the glazing,smooths out sound transmission loss around the mass / spring / mass frequency of the glazing and improves the acoustic insulation of the glazing over a wider frequency band around the mass / spring / mass frequency of the glazing.

[0171] Even more preferably, the glazing according to the invention further comprises one or more additional sound insulation devices. Each additional sound insulation device comprises a plate comprising a plurality of perforations arranged periodically and delimiting a chamber arranged in the cavity. Preferably, the periodicities of the perforations of the polymer foam plate of the device according to the invention and of the plate of each additional sound insulation device are different from each other.

[0172] For example, the glazing according to the invention may comprise: - a first sound insulation device according to the invention, as described above, comprising a first perforated polymer foam plate delimiting a first chamber, the system constituted by the first perforated polymer foam plate and the first chamber being configured to resonate at a first frequency, - a second additional sound insulation device comprising a second perforated plate delimiting a second chamber, the system constituted by the second perforated plate and the second chamber being configured to resonate at a second frequency corresponding to a third of an octave below the first frequency, and - a third additional acoustic insulation device comprising a third perforated plate delimiting a third chamber, the system constituted by the third perforated polymer foam plate and the third chamber being configured to resonate at a third frequency corresponding to a third octave above the first frequency.

[0173] Each additional sound insulation device may be a conventional sound insulation device. Alternatively or additionally, the plate of each additional sound insulation device may comprise a polymer foam, as defined above.

[0174] In advantageous embodiments, the glazing according to the invention may have higher acoustic insulation (determined for example by a measurement of the acoustic reduction index, in particular according to the ISO 10140 standard) than an identical glazing but not comprising perforations arranged periodically in the polymer foam plates of the device, over a frequency range from 200 to 2000 Hz, preferably from 100 Hz to 5000 Hz, more preferably from 50 Hz to 20,000 Hz.

[0175] The glazing according to the invention can be used in any application using glazing. In particular, the glazing according to the invention can be building glazing. The glazing can be intended to provide the interface between the exterior and the interior of the building, and can for example be facade glazing, window glazing or door glazing. Alternatively, the glazing can be intended to be placed inside the building.

[0176] The invention also relates to a method of manufacturing glazing as described above comprising: - the supply of at least two glass walls; - the supply of a device as described above; - the arrangement of the two glass walls so as to form a cavity between them; and - the introduction of the device into the cavity.

[0177] Particularly preferably, the device is placed in the cavity of the glazing so that the chamber delimited by the perforated polymer foam plate of the device is in fluid communication with the cavity of the glazing via the perforations of the polymer foam plate of the device.

[0178] Preferably, when the device is a spacing device, the manufacturing method comprises a step of fixing the two glazed walls to the spacing device. More preferably, when the spacing device comprises at least one perforated profile 1 or a perforated box 21, the two glazed walls are fixed to the spacing device so that the upper wall of the spacing device comprising the perforations arranged periodically faces the cavity formed between the glazed walls of the glazing.

Claims

Claims

1. Glazing (10, 20, 30) comprising at least two glazed walls (7, 17, 27) forming a cavity between them, wherein the cavity comprises at least one acoustic insulation device comprising at least one polymer foam plate (3, 11, 23), said at least one polymer foam plate (3, 11, 23) comprising a plurality of perforations (6, 16, 26) arranged periodically and delimiting a chamber (2, 12) arranged in the cavity, and wherein the acoustic insulation device comprises an inner part facing the chamber and an outer part oriented opposite to the inner part, the average proportion of open cells of the polymer foam in the inner part being greater than the proportion of open cells in the outer part.

2. Glazing (10, 20, 30) according to claim 1, wherein the acoustic insulation device comprises a profile or box formed from a plurality of polymer foam walls, the chamber being an internal space of the profile or box delimited by the walls, and the polymer foam plate comprising the plurality of periodically arranged perforations being one of the walls of the profile or box.

3. Glazing (10, 20, 30) according to claim 1 or 2, wherein the acoustic insulation device is a glazing spacer device.

4. Glazing (10, 20, 30) according to one of claims 1 to 3, in which the average proportion of open cells of the polymer foam in the interior part is between 30% and 99%.

5. Glazing (10, 20, 30) according to any one of claims 1 to 4, in which the acoustic insulation device is in one piece.

6. Glazing (10) according to claim 1 or 2, in which the acoustic insulation device comprises at least one rectilinear bar (11) forming said at least one polymer foam plate, associated with a spacing device, the chamber being delimited by the polymer foam plate and by an edge of the glazing.

7. Glazing (10) according to claim 6, in which the polymer foam comprises an average proportion of open cells of 30 to 99%, preferably of 65 to 98%.

8. Glazing (10, 20, 30) according to one of claims 1 to 7, in which the polymer foam is selected from the group consisting of silicone foams, polyurethane foams, polyethylene foams, melamine foams, and combinations thereof.

9. Glazing (10, 20, 30) according to one of claims 1 to 8, comprising a desiccant agent in the acoustic insulation device or associated therewith.

10. Glazing (10, 20, 30) according to claim 9, in which the desiccant is integrated into the polymer foam.

11. Glazing (10, 20, 30) according to claim 9 or 10, wherein the desiccant is arranged in at least one envelope, which preferably is held inside or outside the chamber.

12. Glazing (10, 20, 30) according to any one of claims 1 to 11, wherein said at least one polymer foam plate (3, 11, 23) comprises at least three perforations (6, 16, 26), preferably at least four perforations (6, 16, 26).

13. Glazing (10, 20, 30) according to one of claims 1 to 12, further comprising one or more additional sound insulation devices, each additional sound insulation device comprising a plate comprising a plurality of perforations arranged periodically and delimiting a chamber arranged in the cavity, wherein preferably the periodicities of the perforations of said polymer foam plate and of said plate of each additional sound insulation device are different from each other.

14. Glazing (10, 20, 30) according to claim 13, wherein the plate of each additional acoustic insulation device comprises a polymer foam.

15. Glazing (10, 20, 30) according to one of claims 1 to 14, in which the acoustic insulation device is positioned in a peripheral zone of the cavity of the glazing (10, 20, 30).

16. Glazing (10, 20, 30) according to one of claims 1 to 15, being building glazing, such as facade, window or building door glazing or interior glazing.

17. Acoustic insulation device comprising at least one plate (3, 11, 23) made of polymer foam, said plate (3, 11, 23) comprising a plurality of perforations (6, 16, 26) arranged in such a way that periodic, wherein the sound insulation device comprises an inner part intended to face the chamber of a glazing unit according to one of claims 1 to 16, and an outer part oriented opposite to the inner part, the average proportion of open cells of the polymer foam in the inner part being greater than the proportion of open cells in the outer part, said device being suitable for the manufacture of a glazing unit according to any one of claims 1 to 16.