WO2020260622A1

WO2020260622A1 - Double-walled unit

Info

Publication number: WO2020260622A1
Application number: PCT/EP2020/068082
Authority: WO
Inventors: Marc MICHAU; Jean-Philippe Boure; Antoine LALLEMENT
Original assignee: Saint-Gobain Glass France
Priority date: 2019-06-27
Filing date: 2020-06-26
Publication date: 2020-12-30
Also published as: EP3990744A1; FR3097893B1; FR3097893A1

Abstract

Double-walled unit. The invention relates to a unit comprising a double wall and an active control system. The double wall defines a cavity. The active control system comprises one or more loudspeakers which are arranged in the cavity. Each of the one or more loudspeakers has a membrane. At least one loudspeaker is arranged in such a manner that its membrane is substantially parallel with the walls of the double wall and the loudspeaker has a thickness which is strictly less than the thickness of the cavity. The invention constitutes an improved unit comprising a double wall and an active control system.

Description

Title of the invention: Double wall installation

[FIELD OF THE INVENTION

The present invention relates to an installation comprising a double wall and an active control system, and an active control method of the installation.

TECHNICAL BACKGROUND

[0002] Partitions and glazing systems in buildings sometimes have double walls allowing the acoustic and thermal insulation of spaces. Some of these double walls have insufficient acoustic insulation performance and need to be improved.

[0003] In the state of the art, there are active control isolation solutions based on the principle of conventional loudspeakers (electrodynamics), that is to say a system comprising an electromagnetic coil, a magnet and a radiant membrane. Such solutions are in particular proposed in documents EP131256B1, WO201777234A1 and WO201777236A1. Other solutions use so-called "EAP" technologies for "Electro Active

Polymer ", based on a surface principle that actively reacts directly under an electric field (closer to the piezoelectric effect). The

EAP technologies are discussed in US8183739B2 and "Sound radiation properties of dielectric elastomer electronegative polymer

loudspeakers ”, art. No. 61681 M Article in Proceedings of SPIE - The

International Society for Optical Engineering 6168 March 2006 DOI:

10.1 1 17 / 12.659700.

[0004] All these solutions consider a mobile element and / or a surface

radiating perpendicular to the panes. This requires the use of components that are constrained in size and / or complex, and therefore expensive.

[0005] There is therefore a need for an improved installation comprising a

double wall and an active control system. SUMMARY OF THE INVENTION

An installation is proposed comprising a double wall and an active control system. The double wall defining a cavity. The active control system includes one or more loudspeakers arranged in the cavity. Each of the one or more speakers has a membrane. At least one of the loudspeakers is arranged so that its membrane is essentially parallel to the walls of the double wall. In addition, one or more of the loudspeakers can be arranged differently, in particular so that the membrane is essentially perpendicular to the walls of the double wall. However, it is preferred that all the loudspeakers are arranged so that their respective diaphragms are essentially parallel to the walls of the double wall.

[0007] In some embodiments, the loudspeaker has a width strictly greater than the thickness of the cavity and / or a length strictly greater than the thickness of the cavity.

[0008] In some embodiments, the speaker has a thickness

strictly less than the thickness of the cavity.

[0009] In certain embodiments, the cavity has a thickness of 16 mm and the loudspeaker has a width and / or a length greater than or equal to 20 mm, preferably greater than or equal to 25 mm, preferably even greater or equal to 30 mm.

In some embodiments, the loudspeaker comprises a box with an orifice closed by the membrane, the box comprising a wall with one or more holes, the wall with the holes being essentially perpendicular to the membrane.

In some embodiments, the diameter of the holes is between 0.5 and 20 mm, preferably 0.7 to 10 mm.

[0012] In some embodiments, the installation comprises a number of loudspeakers between 2 and 10, and preferably equal to 4.

In some embodiments, the number of speakers is equal to 4 and the walls of the double wall are rectangular in shape having 4 sides, the cavity comprising 4 zones which each border a respective side, each of the zones comprising a single loudspeaker.

[0014] In some embodiments, the active control system further comprises one or more microphones, preferably 4 microphones, the

microphones are preferably arranged non-symmetrically.

[0015] In some embodiments, the walls of the double wall are glazed, the installation preferably being a double glazing installation.

[0016] In some embodiments, the installation comprises a spacer

bordering the cavity and a frame bordering the spacer, the or each loudspeaker being arranged according to any one of the following arrangements:

- the loudspeaker is placed on the spacer;

- the loudspeaker is integrated into the spacer; or

- the loudspeaker is placed in the frame, under a hole made in

the spacer, the hole being preferably covered with a mesh.

[0017] In some embodiments, all the speakers are arranged

according to the same provision.

[0018] The invention also relates to a method of active control of the above installation, the method being executed by a controller of the active control system, the active control system comprising one or more microphones located in the cavity, the process comprising:

- the acquisition (S10), by one or more microphones, of measurements relating to noise and / or vibrations in the cavity;

- the determination (S20), by the controller, of data relating to anti-noise and / or anti-vibrations, the determination being based on measurements relating to noise and / or vibrations in the cavity ; and

- emission (S30), by the loudspeaker (s), of anti-noise and / or anti-vibration, the emission (S30) being based on data relating to anti-noise and / or to anti-vibrations.

[0019] The above constitutes an improved installation comprising a double wall and an active control system. [0020] In particular, the arrangement of one or more loudspeakers (for example all loudspeakers) each so that its respective membrane is essentially parallel to the walls of the double wall makes it possible to use (eg. incorporating loudspeakers with relatively large membranes into the active control system. Indeed, this arrangement makes it possible not to limit the size and / or the dimensions of the membrane to the thickness of the cavity (eg the distance separating the glazed walls of a double glazing), since the membrane is essentially perpendicular to the thickness of the cavity. For example, if the membrane is relatively rectangular in shape, with this arrangement, the membrane may have a length and / or a width greater than the thickness of the cavity. Alternatively, if the membrane is relatively circular in shape, the membrane may have a diameter greater than the thickness of the cavity. In addition, this arrangement makes it possible to use loudspeakers having a moving element (eg a magnet) of significant mass.

Thus, the arrangement of one or more loudspeakers is such that at least one loudspeaker (for example each loudspeaker) can have a

membrane (also called radiating surface) having a large surface and optionally a mobile element {e.g. a coil on a support) of significant mass.

This is especially the case in the embodiments where said at least one loudspeaker (for example and preferably each loudspeaker) has a width strictly greater than the thickness of the cavity and / or a length strictly greater than the thickness of the cavity.

The active control system comprising loudspeakers arranged in this way (and optionally loudspeakers arranged differently) can be used in any method of active control of the installation in which the one or more loudspeakers emit anti-noise and / or anti-vibrations in the cavity in response to noise and / or anti-vibrations measured in the cavity, and in order to attenuate this noise and / or these anti-vibrations. Due to its arrangement parallel to the walls, a loudspeaker can, as discussed above, have a membrane having a large surface area and optionally a mobile element of large mass. This makes the active control method particularly effective, especially at low frequencies. The importance of the surface of the membrane improves noise and / or vibration attenuation. Indeed, having a membrane having a large surface area allows the loudspeaker to generate anti-noise and / or anti-vibrations effectively, for example enough to allow attenuation at low frequencies. The low frequency attenuation is further improved by the high mass of the moving element. Further, in embodiments where said at least one loudspeaker (eg each loudspeaker) comprises a box including a wall with holes, the attenuation of noise and / or vibration is further improved. Indeed, as discussed more fully below, the bandwidth

(response) of the complex formed by the loudspeaker with its box is then improved in the low frequencies, which for example makes it possible to compensate for possible breathing phenomena in the cavity.

[0024] In addition, the arrangement of the speakers makes it possible to limit the speaker size constraints due to the thickness of the cavity. This allows, for example, the use of commercial electronic speakers which are inexpensive and which allow the active control system to achieve good performance when actively controlled at low frequencies.

By "active control at low frequencies" is meant active control, by the active control system, of the installation when the noise and / or the vibrations in the cavity have a frequency which varies in a range of so-called "low" frequencies. The frequency range is for example a frequency band located around the breathing frequency of the double wall. The respiration frequency is located for example between 200 Hz and 300 Hz, for example between 220 Hz and 280 Hz in the case of a double glazing comprising an air space 16 mm thick between sheets of glass 4 mm thick. The respiration rate may be different with other wall configurations.

[0026] A method of active control of the installation is also proposed. The

process is executed by an active control system controller. The active control system includes one or more microphones located in the cavity. The method comprises acquiring, by the one or more microphones, measurements relating to noise and / or vibrations in the cavity. The method further comprises determining, by the controller, data relating to anti-noise and / or anti-vibrations. The determination is based on measurements relating to noise and / or vibration in the cavity. The method further comprises emission, by the speaker (s), of anti-noise and / or anti-vibration. The emission is based on data relating to anti-noise and / or anti-vibrations.

[0027] This constitutes an improved method of active control. Indeed, as discussed above, the arrangement of the loudspeaker (s) of the active control system, so that their respective membranes are essentially parallel to the walls of the double wall, makes the active control method particularly effective, especially at low frequencies. The active control method is further improved in embodiments where said at least one loudspeaker (eg and preferably each loudspeaker) comprises a box comprising a wall with holes, as discussed above.

BRIEF DESCRIPTION OF THE FIGURES

[0028] The accompanying drawings illustrate the invention:

[0029] [Fig.1] illustrates an example of an installation according to the invention.

[0030] [Fig.2] illustrates an example of a loudspeaker of the installation according to the invention.

[0031] [Fig. 3] illustrates an example of an installation according to the invention.

[0032] [Fig. 4] illustrates an example of an installation according to the invention.

[0033] [Fig. 5] schematically illustrates an example of a controller that can be part of the active control system and that can be used to implement the active control method.

[0034] [Fig. 6] shows a flowchart illustrating embodiments of the

active control process.

[0035] [Fig. 7] illustrates the profile of the sound reduction index (ordinate, dB) as a function of frequency (abscissa, Hz) for an example of an installation according to the invention, with and without implementation of active control.

DETAILED DESCRIPTION OF THE INVENTION

The invention is now described in more detail and in a non-limiting manner in the description which follows. Double wall installation:

[0037] The installation comprises a double wall. Thus, the installation may hereinafter be referred to as "double-walled installation". By double-walled installation is meant a building installation comprising at least two walls.

The installation can in particular be a window, a facade or a partition, glazed or unglazed (preferably glazed). The double-walled installation according to the invention can be used as a building window. By "window" is meant a component of the building intended to close a wall opening, allowing the passage of light and possibly ventilation. By "facade" is meant the outer surface of a wall delimiting a building, generally not having a load-bearing function and may be of the curtain, cladding or other facade type.

An attachment and spacing device connects the two walls and fix them so that they are essentially parallel to one another. Any contact between the fastening device and each of the two walls is made on the edge of the wall, so that the fastening and spacer device and the two walls thus fixed define a cavity between the two walls. The cavity is thus a volume between the two walls. The cavity can for example be filled with air or a rare gas. The cavity may in particular have a thickness of between 10 and 30 mm, for example between 16 and 20 mm, for example equal to 16 mm. Each wall can be transparent. For example, each wall can be a sheet of glass. In this case, the cavity can also comprise a third transparent wall (in particular a third sheet of glass) parallel to the two walls, for example if the installation is a triple glazing. Each sheet of glass may be a sheet of mineral glass, in particular an oxide glass which may be a silicate, borate, sulfate, phosphate, or the like. Alternatively, it may be a sheet of organic glass, for example made of polycarbonate or of polymethyl methacrylate. The glass sheets can be annealed, laminated, or tempered glass. By “tempered glass” is meant glass treated by rapid cooling processes, with the aim of increasing the resistance of the glass to impact. The term “laminated glass” is understood to mean at least two sheets of glass between which is inserted at least one interlayer film generally of viscoelastic plastic nature. In the context of the invention, a sheet of laminated glass (comprising two sheets of glass and the interlayer film) will be considered like one sheet and not two. The plastic interlayer film may comprise one or more layers, preferably one or two layers, of a viscoelastic polymer such as polyvinyl butyral (PVB). The interlayer film may be standard PVB or acoustic tri-layer PVB. Alternatively, each wall can be opaque, for example if the double-walled installation is an unglazed partition (“partition wall”).

[0039] The installation can in particular be insulating glazing, in particular double glazing or triple glazing, or else an unglazed partition ("partition wall").

[0040] In some embodiments, the walls of the double wall are glazed, the installation preferably being a double glazing installation. Each of the two glass walls can have a thickness of 4 mm and the cavity can have a thickness of 16 mm.

[0041] The attachment and spacing device preferably comprises a spacer ("spacer") connecting and spacing the two walls.

[0042] The spacer can be made of a metallic material and / or of a polymer material. Examples of metallic materials include aluminum and stainless steel. Examples of polymeric materials include polyethylene, polycarbonate, polypropylene, polystyrene,

polybutadiene, polyisobutylene, polyesters, polyurethanes,

polymethyl methacrylate, polyacrylates, polyamides, polyethylene terephthalate, polybutylene terephthalate, acrylonitrile butadiene styrene, acrylonitrile styrene acrylate, styrene-acrylonitrile copolymer, and combinations thereof. The polymeric material can be reinforced with glass fibers.

[0043] The side faces of the spacer are fixed to each of the walls

(in particular glass sheets) by means of fixing means by gluing, which constitutes a first sealing barrier, preferably to air, gas and water vapor, such as for example polyisobutylene (PIB).

Between the face of the spacer facing outwards and the edge of the walls, the installation further preferably comprises a seal (sealing mastic), forming a second sealing barrier, preferably with water, such as for example polyurethane, polysulphide or silicone. This seal sealing also makes it possible to fix the spacer to the walls and to ensure mechanical strength over time.

When the spacer is made of a polymer material, it may include on its surface facing the outside of the installation a metallic coating, for example of the stainless steel type, forming a barrier against liquid water, gas and water vapor.

[0046] The installation can also include a frame for the walls, for example for the glass sheets. More particularly, the walls can be

framed around their entire periphery by a frame made of profiles, for example anodized aluminum. This frame can in particular be glued directly to the periphery and to the external faces of the walls. The frame may further border the spacer (on the outside of the cavity), the spacer preferably being attached to the frame with putty.

[0047] FIG. 1 schematically illustrates a sectional view of an example installation which is a double glazing installation. The double glazing comprises two sheets of glass 10 and 12. In the part of the installation shown in Fig. 1, the glass sheets are framed around their entire periphery by a frame 14. The edges of the two glass sheets 10 and 12 are attached to a spacer 18, mastic 16 ensuring the sealing of the assembly. The installation comprises a cavity 104 delimited by the two glass sheets 10 and 12 and the spacer 18. In the part of the installation shown in FIG. 1, a loudspeaker 100 is disposed in the cavity 104, on the spacer 18. The loudspeaker 100 is arranged so that its membrane 102 is essentially parallel to the sheets of glass 10 and 12.

Active control system:

By active control system is meant any system making it possible to carry out an active control method of the installation. By method of active control of the installation is meant any method comprising at least the acquisition and / or the calculation of measurements relating to noise and / or vibrations in the cavity, as well as the determination and emission, according to measurements relating to noise and / or vibrations in the cavity, anti-noise and / or anti-vibrations, the anti-noise and / or anti-vibrations being such that their emission into the cavity allows or aims to allow sound insulation of the double wall. By sound insulation is meant an attenuation, or even a suppression, of the noise and / or vibrations which are emitted outside the installation, on one side of one of the two walls, and pass through the installation as far as to the other side of it. This sound insulation can include minimizing the root mean square sound pressure exerted on devices (eg microphones) measuring noise and / or vibrations in the cavity.

The active control system comprises one or more loudspeakers

arranged in the cavity. Each of these one or more loudspeakers can be any loudspeaker capable of emitting anti-noise and / or anti-vibration into the cavity, such as for example an inertial actuator of size 30-32 mm. Each of these loudspeakers includes a membrane. The speaker membrane is fully in contact with the air in the cavity. At least one of the one or more loudspeakers (for example each loudspeaker) is further arranged so that its membrane is essentially parallel to the walls of the double wall (the latter being essentially parallel). The membrane can be

mostly flat. The membrane may for example have an essentially rectangle or square shape. Alternatively, the membrane may for example have an essentially disc shape, or an ellipse. The anti-noise and / or anti-vibrations are produced by the membrane which vibrates the ambient air (i.e. the air inside and outside the speaker). The loudspeaker may be in the form of a box, for example having a shape

essentially straight pavement, including one of the walls {e.g. faces) is the membrane or includes an orifice in which the membrane is located. The box may contain air, which is therefore air inside the speaker.

Each loudspeaker can be a magnet loudspeaker, comprising a

magnet and an electromagnetic coil in addition to the membrane. The magnet and the coil convert electrical energy into mechanical energy which is transmitted to the membrane. The membrane transmits mechanical energy to the surrounding air, causing it to vibrate. Alternatively, the loudspeaker can be a piezoelectric loudspeaker. A piezoelectric speaker includes a

ceramic or a piezoelectric polymer to which a radiating membrane is attached. Ceramic or polymer transforms electrical energy into mechanical energy (preferably proportional), which is transmitted to the membrane. The membrane transmits mechanical energy to the ambient air, thus creating an acoustic wave.

[0051] In embodiments, said at least one loudspeaker, which is

arranged so that its membrane is essentially parallel to the walls of the double wall, has a width strictly greater than the thickness of the cavity and / or a length strictly greater than the thickness of the cavity. In some embodiments, each loudspeaker which is arranged so that its respective membrane is essentially parallel to the walls of the double wall has a width strictly greater than the thickness of the cavity and / or a length strictly greater than the thickness of the cavity

Thus, the membrane of (e.g. Of each) loudspeaker can have

dimensions greater than the thickness of the cavity. For example, if the membrane is essentially disc-shaped, the membrane may have a diameter greater than the thickness of the cavity. Alternatively, if the membrane has an essentially rectangle or square shape, the membrane may have a length greater than the thickness of the cavity and / or a width greater than the thickness of the cavity. Using one or more loudspeakers each having a diaphragm with such dimensions in an active control process improves the performance of active control, especially at low frequencies.

[0053] In embodiments, said at least one loudspeaker {e.g. each speaker) has a thickness strictly less than the thickness of the cavity. This ensures that there is no contact between the speaker membrane and a wall of the double wall, which would attenuate or prevent the emission of anti-noise and / or anti-vibration by the speaker. This also makes it possible not to have a too thin air gap between the membrane and a wall of the double wall, which could cause a viscous damping phenomenon, eg during the emission of anti-noise and / or d 'anti-vibration by the loudspeaker, for example during an active test.

The concepts of thickness of the cavity, thickness of the loudspeaker, length of the loudspeaker and width of the loudspeaker are now more fully discussed. The thickness of the cavity denotes the distance separating the two walls of the double wall, the latter being essentially parallel. The loudspeaker thickness refers to the maximum dimension of the loudspeaker in the direction perpendicular to the diaphragm (or to the mean plane of the diaphragm). Speaker length and speaker width refer to two other main dimensions of the speaker that are perpendicular to the thickness. In particular, when the walls of the loudspeaker are of rectangular shape, the width and the length are those of the rectangle formed by each wall perpendicular to the membrane (or to the mean plane thereof).

[0056] FIG. 2 shows a side view of an example of an active control system speaker. The loudspeaker shown in Fig. 2 is in the form of a box 20. The box includes a hole 22 in which the speaker membrane 24 is located. More precisely, the membrane 24 blocks the orifice 22, and therefore constitutes a wall of the box 20. The double arrow 28 schematically represents the thickness of the loudspeaker. The double arrow 26 schematically represents one of the two remaining dimensions of the loudspeaker, for example the width (resp. The length). The length (resp. The width) of the loudspeaker is the remaining dimension of the loudspeaker, the one whose direction corresponds to the direction from the point of view of Fig. 2.

[0057] In some embodiments, the cavity has a thickness of 16 mm. In these embodiments, said at least one loudspeaker (eg. Each loudspeaker) has a width and / or a length greater than or equal to 20 mm, by preferably greater than or equal to 25 mm, preferably still greater or equal to 30 mm. For example, said at least one loudspeaker (eg each loudspeaker) may have a width comprised between 30 mm and 32 mm and / or a length comprised between 30 mm and 32 mm. In these embodiments, said at least one loudspeaker (eg each loudspeaker) can also have a thickness less than 14 mm. These loudspeakers, by their dimensions, are particularly effective for carrying out active control of the double wall, and it is only possible to use them in a cavity of such thickness thanks to their particular arrangement {ie the membrane essentially parallel to the walls of the double wall). In these embodiments, each of the one or more loudspeakers can for example be an inertial actuator known as a “size 30-32 mm inertial actuator”.

[0058] In some embodiments, said at least one loudspeaker (e.g. Each loudspeaker) comprises a box with an orifice in which the membrane is located. The box includes a wall with holes. The wall with the holes is essentially perpendicular to the membrane. The membrane, when it vibrates, thus vibrates the air in the cavity (i.e. outside the box) and the air inside the box. Said at least one loudspeaker {e.g. each loudspeaker) then behaves like a Helmoltz resonator, and its power is then particularly important. The holes can also allow, in

increasing the power of the loudspeaker (s), to compensate for a possible breathing phenomenon, which consists of a resonance of the movement of the walls creating an overpressure in the cavity. This breathing phenomenon occurs in a certain frequency range {i.e. noise and / or vibration) in the cavity. The frequency range is, for example, 220 to 280 Hz in a double glazing installation whose glass walls are 4 mm thick and where the thickness of the cavity is 16 mm.

By "a loudspeaker comprises a box", it should be understood that the loudspeaker is in the form of a box, for example in which the loudspeaker components are arranged. The box may also be referred to as a "case". The box, for example, has the shape of an essentially straight pad. The box includes several walls defining a space in which the loudspeaker components are arranged, the space including an air cavity. One of these walls is or comprises an orifice in which the membrane is located. The membrane can thus be in the space in which the

loudspeaker components, and for example be arranged so

essentially parallel to the hole. Alternatively, the orifice can

correspond to the location of the diaphragm, that is, the diaphragm is placed so that it fills the orifice, and thus forms part of a wall of the box or a wall of the box.

As said above, the box includes another wall with holes.

This wall is essentially perpendicular to the membrane. The membrane being essentially parallel to the walls of the double wall, the wall with holes can thus be oriented towards the cavity. For example, the wall with holes can be oriented away from a spacer of the double wall.

The holes located on the wall with holes are arranged so that the response of the low frequency speaker is improved. For example, the holes can be lined up with regular spacing towards the middle of the wall. The diameter of each hole can be between 0.5 mm and 20 mm, their number can vary from 1 to 50 and the spacing between adjacent holes can vary from 1 mm to 50 mm. When a single surface hole S is drilled in the wall of thickness e and considering that the loudspeaker housing has a volume V, the resonant frequency of the system is given by the formula:

[Math 1] f _r where c is the speed of sound in air.

[0062] The surface S is then optimized in order to obtain the correct frequency of

resonance. In the case where several holes are present, the optimization is usually done experimentally. For example, 5 holes about 1mm in diameter and aligned with a 7mm spacing have been shown to improve speaker performance.

[0063] In some embodiments, the installation comprises a number of loudspeakers between 2 and 10. In these embodiments, the number of loudspeakers is preferably equal to 4.

In some embodiments, the number of loudspeakers is equal to 4 and the double wall is of rectangular shape with 4 sides. In these modes of

embodiment, the cavity comprises 4 zones which each border a respective side. Each of the zones comprising a single loudspeaker. The loudspeaker may or may not be centered on a respective zone.

[0065] In some embodiments, the installation comprises a spacer bordering the cavity and a frame bordering the spacer, and the or each loudspeaker is arranged according to any of the following arrangements:

- the loudspeaker is placed on the spacer;

- the loudspeaker is integrated into the spacer; or the loudspeaker is placed in the frame, under a hole in the spacer, the hole preferably being covered with a mesh.

[0066] These embodiments are now discussed.

One or more loudspeakers, for example all the loudspeakers, can thus be arranged on the spacer, for example by being fixed (eg. Glued) on the spacer or on a support itself fixed to the spacer. When a loudspeaker includes a box, placing the speaker on the spacer may mean that the box is placed on the spacer, for example one wall of the box being attached to the spacer. In such cases, the wall with the holes in the box may be essentially parallel or perpendicular to the spacer, while being essentially perpendicular to the membrane.

[0068] In the double glazing installation shown in FIG. 1, the speaker 100 is disposed on the spacer 18.

[0069] FIG. 3 shows a schematic view of an example of the installation, in embodiments where the installation is a double glazing installation, and where a speaker is disposed on the spacer. The installation includes a spacer 32 and mastic 36, as previously discussed. A loudspeaker 34 is disposed on the spacer 32, the membrane of the loudspeaker 34 being

essentially parallel to a glazed wall 30 of the double glazing.

[0070] Alternatively or additionally, one or more loudspeakers, for example all the loudspeakers, can be integrated into the spacer. By "a speaker is built into the spacer" it is understood that the spacer is perforated and / or cut so that the spacer has an empty space with the speaker placed in that empty space. For example, if the double wall is rectangular in shape with 4 sides, the spacer may be, on each side, in the form of a bar connecting the two walls and bordering the cavity. Thus, the spacer corresponds to 4 bars, each on a respective side. Each bar can be cut in half, thereby separating the bar into two parts, and a loudspeaker can be inserted between the two parts.

Alternatively or additionally, one or more loudspeakers, for example all loudspeakers, can be arranged in the frame (ie integrated into the frame), under a hole in the spacer, the hole preferably being covered of a stitch. The mesh can be any porous material, for example a fabric or any moisture-proof nonwoven material, which covers and plugs the hole.

[0072] FIG. 4 shows a schematic view of an example of the installation, in embodiments where the installation is a double glazing installation, and where a loudspeaker is disposed in the frame. The installation includes a spacer 42 and putty 46, as previously discussed. A loudspeaker 48 is integrated into the frame of the double glazing. The loudspeaker 48 is disposed under a hole in the spacer 42, the hole being covered by a mesh 44. Although not visible in FIG. 4, the speaker membrane 48 is essentially parallel to a glass wall 40 of the double glazing.

It should be noted that, with regard to said at least one loudspeaker (for example of each loudspeaker), that the loudspeaker is integrated into the spacer, or that it is arranged in the frame , under a hole in the spacer, the loudspeaker is arranged so that its membrane is essentially parallel to the walls of the double wall.

[0074] Other active control system components are now discussed.

The active control system can include any means or device

acquisition of measurements relating to noise and / or vibrations in the cavity. Noise and / or vibrations are noise and / or vibrations in the cavity, but can come from noise and / or vibrations emitted outside the cavity and having passed through one of the two walls or both walls. The term “measurement relating to noise and / or vibrations” is understood to mean any digital quantity measured or calculated at a location in the cavity and making it possible to quantify the noise and / or vibrations in the cavity at this location in the cavity. The digital quantity can be any physical measurement acquired by physical means, for example a voltage. The measurements relating to noise and / or to vibrations may be measurements of acoustic pressure, for example in the form of a voltage representative of this pressure. The acquisition means can be any acquisition means, such as for example one or more microphones, one or more accelerometers or one or more piezoelectric sensors, and preferably one or more microphones. [0076] In some embodiments, the active control system comprises one or more microphones, preferably 4 microphones. Microphones are a means of acquiring measurements relating to noise and / or vibrations in the cavity. The microphones can for example all be configured to provide a voltage representative of an acoustic pressure. The microphones are arranged in the cavity, for example all on the edges of the cavity, for example fixed (eg. Glued) to a spacer or integrated into the spacer. If the double wall is rectangular in shape with 4 sides, the cavity comprising 4 zones each bordering a respective side, there may preferably be 4 microphones, one in each respective zone.

Preferably, the microphones are arranged non-symmetrically. By this is meant that the one or more microphones are not located at symmetrical positions {e.g. edge) of the cavity. By this is meant that, relative to the geometry of the cavity or the edge of the cavity, there is no symmetry (axial or central) in the way the one or more microphones are positioned. For example, the positions of microphones do not form the vertices of a regular polygon. Positioning the one or more microphones asymmetrically prevents the positions of one or more microphones from being in phase with periodicities of noise and / or vibrations in the cavity.

[0078] In some embodiments, the microphones can be attached, by

glued example, on a spacer or on respective studs themselves fixed, for example glued, on the spacer. In embodiments, the microphones can be integrated into or on the spacer.

The active control system can also include any system

IT suitable for the implementation of any active control method of the installation, for example the active control method which will be discussed below.

This computer means can be a controller.

The controller is suitable for determining, from measurements of noise and / or vibrations in the cavity (eg acquired by the microphones), data relating to anti-noise and / or anti-vibrations which , if they are emitted into the cavity, improve the acoustic insulation of the double wall. The controller can be connected by wires to a power supply. The controller can also be connected to one or more microphones by wires, which allows the microphones to transmit to the controller the measurements they have acquired, for example each in the form of a voltage representative of an acoustic pressure. The controller can also be connected to one or more loudspeakers by wires, which allows the controller to transmit data relating to anti-noise and / or anti-vibration to one or more loudspeakers. , for example in the form of a voltage representative of these data. Based on this data, the one or more loudspeakers may emit anti-noise and / or anti-vibration into the cavity. In embodiments where the double wall installation is double glazing (or triple glazing), the controller, the power supply, and / or the wires connecting the controller to the controller.

the power supply and / or sensors can be deported or hidden in the frame. The wires can pass through the spacer.

[0081] An example of the controller will now be described with reference to FIG. 5.

[0082] The controller illustrated in FIG. 5 is a DSP 1000 controller comprising a DSP processor 1010 coupled to a memory device 1020. The memory device 1020 may include random access memory (RAM) and read only memory (ROM, EPROM or Flash EPROM). The read only memory is adapted to tangibly represent computer program instructions for the execution of the steps of an active control method. RAM is suitable for storing data during program execution. The controller may further include one or more I / O (Input / Output) ports 1030 coupled to the processor. The one or more I / O ports 1030 connect the outputs and inputs of the controller 1000 to the rest of the controller 1000, and can additionally receive interface signals 1100. Interface signals 1100 are physical signals representative of operating instructions. control and / or monitoring sent to the controller 1000, for example by a user via a user interface. DSP processor 1010, memory device 1020, and the one or more ports 1030 are interconnected by a computer bus (not shown in Fig. 5) allowing data to flow. The controller 1000 takes as input a measured signal 1080. The measured signal 1080 designates any analog physical signal, for example a voltage, representative of measurements acquired by one or more microphones. The controller 1000 can thus be connected, for example by wires, to one or more microphones. The controller outputs a control signal 1090. The control signal refers to any analog physical signal, for example a voltage. The physical signal may for example be representative of data relating to anti-noise and / or anti-vibrations. The controller 1000 can thus be connected, for example by wires, to one or more loudspeakers to which it transmits these data. The controller 1000 can include an analog-to-digital conversion device (ADC, “Analog to Digital Converter”) 1050 whose function is to convert an analog quantity (for example a physical signal, for example a voltage) into a digital value. The analog-to-digital converter 1050 can in particular convert the measured signal 1080 into a digital value, then supplied to the DSP processor 1010. The controller can further include a first low-pass filter 1040, which is a filter allowing the low frequencies of the device to pass. signal measured 1080 and which attenuates high frequencies. The controller 1000 can include a digital-to-analog conversion device (DAC, “Digital to Analog Converter”) 1060 whose function is to convert a digital value into an analog quantity (for example a physical signal, for example a voltage). In particular, the digital-to-analog converter 1060 can convert any digital value output by the DSP processor 1010 into the control signal 1090. The controller can further include a second low-pass filter 1070, which is a low-frequency filter. of the signal emitted by the digital-to-analog converter 1060 and which attenuates the high frequencies.

Active control process:

The active control method is now discussed.

The method is executed by the controller of the active control system. By this is meant that steps (or substantially all of the steps) of the process are performed by the controller or by any such system. Thus, steps of the method are carried out by the controller, possibly completely automatically or semi-automatically. In some embodiments, the triggering of at least part of the steps of the method can be achieved by user-controller interaction. The level of interaction required user-controller may depend on the level of automation desired and may be constrained by the need to implement user wishes. In some embodiments, this level may be user-defined and / or predefined. Steps of the method may further be performed by other devices connected (eg by wires) to the controller, eg microphones and / or speakers, as discussed below.

The method can be implemented by any controller suitable for this purpose,

such as for example the controller previously described with reference to FIG. 5. The controller may include a processor coupled to memory, with a computer program including program code instructions for performing process steps being stored in memory. The processor may be a DSP (“Digital Signal Processor”), particularly suitable for digital signal processing. Memory designates any computer equipment ("hardware") suitable for such storage,

possibly comprising several distinct physical parts (for example one for the program, and possibly one for a database). The controller may be a DSP controller, that is to say comprising a DSP processor, for example an AUDAU1452 DSP controller.

The computer program can include instructions executable by the controller or any computer system of this type, the instructions comprising means for leading the above controller to implement the method. The program can be recorded on any data medium, including system memory. The program may for example be implemented in digital electronic circuits, or in computer hardware, firmware or software, or combinations thereof. The program can be implemented as an apparatus, for example a product tangibly represented in a machine-readable memory device for execution by a programmable processor. Process steps can be performed by a programmable processor executing an instruction program to perform process functions by processing input data and generating outputs. The processor can thus be programmable and be coupled to receive data and instructions from, and to transmit data and instructions to, a memory device, the device. minus one input device and at least one output device. The program can be implemented in a high level procedural or object oriented programming language, or in a machine or assembly language. The language can be compiled or interpreted. The program can be a full installer or an updater. Applying the program to the controller leads to instructions for performing the process.

[0087] With reference to the flowchart of FIG. 6, the method comprises the steps of acquiring S10 measurements relating to noise and / or vibrations, determining S20 of data relating to anti-noise and / or anti-vibrations, and transmitting S30 anti-noise and / or anti-vibration. The process steps are preferably carried out in real time, that is to say

essentially simultaneously and / or with little latency between them

In some embodiments, by "the steps of the method are carried out with little latency between them" is meant that the time necessary for the execution of the steps of the method, for example the time elapsing between the acquisition S10 of measurements relating to noise and / or vibrations and the emission S30 of anti-noise and / or anti-vibrations, is less than a maximum latency time. The maximum latency time may depend on the frequency range in which the frequency of noise and / or vibrations in the cavity is found when carrying out the method. The maximum latency may also depend on the controller. For example, the maximum latency time may depend on the size of a controller RAM area ("buffer") and / or the number of channels on a controller computer bus. In some embodiments, the maximum latency is less than 100 ps, for example when the controller includes an analog-to-digital conversion device (ADC) and a digital-to-analog conversion device (DAC).

[0089] Still with reference to the flowchart of FIG. 6, the process can

comprising, in embodiments, an iteration S40 of the acquisition S10 of measurements relating to noise and / or vibrations in the cavity and of emission S30 of anti-noise and / or anti-vibration. Thus, in these embodiments, the acquisition S10 of the measurements relating to noise and / or vibrations in the cavity, with little latency as discussed above, of remission S30 of anti-noise and / or d 'anti-vibration, the S30 emission itself being followed, always with little latency, by a new S10 acquisition, itself followed, always with little latency, by a new S30 transmission, and so on. It should be understood that any step of the method comprised between an acquisition S10 of the actual measurements and the emission S30 which follows is also iterated. The iteration can last for a given time, for example a time during which it is desired to carry out active control of the installation.

The measurements relating to noise and / or vibrations in the cavity are

S10 acquired by the one or more microphones of the active control system, the positioning / arrangement of which was previously discussed in embodiments of the installation. Each of the one or more microphones acquires one or more measurements. Each microphone is located in the cavity, for example on an edge of the cavity. Thus, any measurement acquired by this microphone is a measurement quantifying the noise and / or vibrations in the cavity at the location where the microphone is located, that is to say in the vicinity of the position of the microphone.

[0091] Still with reference to the flowchart of FIG. 6, the method comprises determining S20, by the controller, of data relating to anti-noise and / or anti-vibration. The determination S20 is based on the measurements relating to noise and / or vibrations acquired S1 O by the one or more microphones.

The data relating to anti-noise and / or anti-vibrations denote any quantification of anti-noise and / or anti-vibrations to be emitted in the cavity to allow the isolation of the double wall. More precisely, these relative data form a physical signal (for example a voltage) carrying the quantification of the anti-noise and / or anti-vibrations to be emitted in the cavity. This physical signal is then transmitted to one or more loudspeakers by the controller. In embodiments of the method, the data relates to noise if the measurements S10 acquired by the one or more microphones relates to noise. In some embodiments, the data relates to vibrations if the measurements S10 acquired by the one or more microphones relate to vibrations.

The data relating to anti-noise and / or anti-vibrations constitute an output of the controller, which takes as input the measurements S10 acquired by the one or more microphones. By the "determination S20 is based on measurements relating to noise and / or vibration", it is meant that the output of the controller is determined (for example calculated) by the controller according to the input of the controller, that is, that is to say as a function of at least some of the measurements S10 acquired by the one or more microphones (for example as a function of all). The determination S20 can be made by executing, by the controller, any algorithm configured to determine, from measurements relating to noise and / or vibration in the cavity, data relating to anti-noise and / or to anti-vibrations to be emitted in the cavity to improve the acoustic insulation of the double wall. This algorithm can be any active control algorithm (or “ANC algorithm”), such as for example an FXLMS (“Filtered-X Least Mean Square”) algorithm.

The data relating to anti-noise and / or anti-vibrations form a physical signal transmitted at the output of the controller to one or more speakers. Each loudspeaker is a physical means capable of receiving this physical signal as an input and of emitting the anti-noise and / or anti-vibration S30, the quantization of which is carried by the physical signal. Thus, by "the S30 emission is based on data relating to anti-noise and / or anti-

vibrations "means that the one or more speakers receive the physical signal as input, then emit the anti-noise and / or anti-vibrations

correspondent (s).

The effectiveness of the active control system is evaluated in the laboratory from the measurement of the sound reduction index of a double glazing of dimensions 1.48 mx 1.23 m composed of two glass walls of 4 mm

thick separated by an air cavity 16 mm thick. Each of the four edges of the double glazing cavity is instrumented with a microphone and a speaker integrated in a box, one wall of which is pierced with five holes; the speaker membrane is parallel to the two glass walls. The measurement of the sound reduction index is carried out according to the requirements described in standard IS015186-1 and summarized below. The surface S double glazing is installed in the separating test opening between two rooms; an emission room in which the average sound pressure level L _p (dB) of the emission noise generated is measured and a reception room in which the level average sound intensity U (dB) is measured on the surface S _m of the double glazing. The sound reduction index Ri (dB) is determined from the equation:

[Math 2]

R, = L _p - 6— [L, + 101og (¾]

The sound reduction index spectra of double glazing measured without control and with control are presented in Fig. 7.

Claims

[Claim 1] [installation comprising:

- a double wall, the double wall defining a cavity; and

- an active control system comprising at least one loudspeaker arranged in the cavity and having a membrane, the loudspeaker being arranged so that its membrane is essentially parallel to the walls of the double wall and the loudspeaker having a thickness strictly less than

the thickness of the cavity.

[Claim 2] Installation according to claim 1, in which the

loudspeaker has a width strictly greater than the thickness of the cavity and / or a length strictly greater than the thickness of the cavity.

[Claim 3] Installation according to any one of claims 1 or 2, in which the cavity has a thickness of 16 mm and in which the loudspeaker has a width and / or a length greater than or equal to 20 mm, preferably greater than or equal to 25 mm, more preferably greater than or equal to 30 mm.

[Claim 4] Installation according to any one of claims 1 to 3, wherein the loudspeaker comprises a box with an orifice closed by the membrane, the box comprising a wall with one or more holes, the wall with holes being essentially perpendicular to the membrane. [Claim 5] Installation according to claim 4, in which the

hole diameter is between 0,

5 and 20 mm, preferably 0.7 to 10 mm.

[Claim 6] Installation according to any one of claims 1 to

5, comprising a number of loudspeakers between 2 and 10, and preferably equal to 4.

[Claim 7] Installation according to any one of claims 1 to

6, in which the number of loudspeakers is equal to 4 and in which the walls of the double wall are rectangular in shape having 4 sides, the cavity comprising 4 zones which each border a respective side, each of the zones comprising a single top -speaker.

[Claim 8] Installation according to any one of claims 1 to

7, wherein the active control system further comprises one or several microphones, preferably 4 microphones, the microphones preferably being arranged non-symmetrically.

[Claim 9] Installation according to any one of claims 1 to

8, in which the walls of the double wall are glazed, the installation preferably being a double glazing installation.

[Claim 10] Installation according to any one of claims 1 to

9, in which the installation comprises a spacer bordering the cavity and a frame bordering the spacer, the or each loudspeaker being arranged according to any one of the following arrangements:

- the loudspeaker is placed on the spacer;

- the loudspeaker is integrated into the spacer; or

- the loudspeaker is arranged in the frame, under a hole in the spacer, the hole preferably being covered with a mesh.

[Claim 1 1] Installation according to claim 10, wherein all the loudspeakers are arranged in the same arrangement.

[Claim 12] Method of active control of the installation according to a

any of claims 1 to 11, the method being performed by a controller of the active control system, the active control system comprising one or more microphones located in the cavity, the method comprising:

- emission (S30), by the loudspeaker (s), of anti-noise and / or anti-vibrations, the emission (S30) being based on data relating to anti-noise and / or anti-vibrations.