Acoustic sound panel and a neck structure insert for use therein

Abstract

The invention relates to an acoustic sound panel, comprising: a back substrate, a core plate arranged parallel to and at the back substrate, wherein the core plate is provided with a plurality of resonator cells arranged next to each other, wherein each of the resonator cells defines a resonating chamber therein, and a front substrate arranged parallel to and at the core plate, so that the core plate is sandwiched between the back substrate and the front substrate, wherein at least a part of the plurality of resonator cells of the core plate is provided with a resonator neck for providing a fluid connection between the resonating chamber and the environment, wherein the resonator necks extend into the resonating chambers of the respective resonator cells, and wherein the front substrate is provided with a plurality of perforations that are aligned with the resonator necks of the resonator cells.

Description

[0001] ACOUSTIC SOUND PANEL AND A NECK STRUCTURE INSERT FOR USE

[0002] THEREIN

[0003] BACKGROUND

[0004] The invention relates to an acoustic sound panel , and a neck structure insert for use in an acoustic sound panel .

[0005] Such an acoustic sound panel is known from the European patent publication no . EP 3 244 038 , which describes an acoustic panel for an aircraft nacelle comprising a core ; a permeable skin coupled to the core ; a permeable septum coupled to the core ; a back skin; and a dividing wall extending between the permeable septum and the back skin, wherein the permeable septum, the dividing wall , and the back skin define a first back cavity, and wherein the first back cavity is in fluid communication with a plurality of cells in the core through the septum .

[0006] SUMMARY OF THE INVENTION

[0007] Passenger safety and comfort remain paramount in the aviation industry . Airlines promote long-haul flights by emphasizing cabin design and amenities such as minisuites , private spaces in first and business classes , spacious seats , and wellness zones for all passengers . Aircraft manufacturers strive to enhance the flying experience through more comfortable designs . However, noise presents a signi ficant challenge . Noise significantly contributes to discomfort in air travel . Materials with good sound absorption properties are typically heavy and require larger volumes , conflicting with the industry' s goal of maintaining lightweight aircraft . For example , in business and corporate j ets , offsetting cabin walls by 50 to 80 mm from fuselage frames accommodates soundproofing treatments needed to achieve "library quiet" noise levels . Controlling sound waves within an aircraft poses a formidable challenge, as effective soundproofing materials are heavy and occupy substantial volumes , reducing cabin space and increasing fuel consumption . Consequently, quiet aircraft often weigh more, incur higher operational costs , and have a more significant environmental impact . In line therewith, a disadvantage of the known acoustic sound panel is that it requires a large volume .

[0008] Current commercial solutions enhance sound absorption by adding porous materials , such as foams and felt, to the backside of cabin elements and applying barriers through rubberi zed membranes . Dense porous materials achieve the desired absorption performance while minimi zing their impact on cabin volume . Rubberized membranes absorb sound through their mass , adding significant weight . Incorporating these soundproofing materials affects aircraft operation and maintenance, leading to higher fuel consumption, increased emissions , and more substantial maintenance burdens .

[0009] It is an obj ect of the present invention to ameliorate or to eliminate one or more disadvantages of the known prior art, to provide an improved acoustic sound panel or to at least provide an alternative acoustic sound panel .

[0010] According to a first aspect , the invention provides for an acoustic sound panel , comprising : a back substrate , a core plate arranged parallel to and at the back substrate, wherein the core plate is provided with a plurality of resonator cells arranged next to each other, wherein each of the resonator cells defines a resonating chamber therein, and a front substrate arranged parallel to and at the core plate, so that the core plate is sandwiched between the back substrate and the front substrate, wherein at least a part of the plurality of resonator cells of the core plate is provided with a resonator neck for providing a fluid connection between the resonating chamber and the environment, wherein the resonator necks extend into the resonating chambers of the respective resonator cells , wherein the front substrate is provided with a plurality of perforations that are aligned with the resonator necks of the resonator cells , and wherein at least a part of the plurality of resonator cells comprises one or more support columns , wherein the one or more support columns extend at least between the back substrate and the end of the resonator neck facing the back substrate , thereby spanning the height of the respective resonator cell .

[0011] The acoustic sound panel according to the invention has a plurality of resonator cells provided in the core plate , wherein at least of the plurality of resonator cells is provided with a resonator neck extending into the resonating chambers . The resonator cells , therefore , are considered to be a Helmholtz resonator, which is a cavity with a volume and a neck opening to the outside air . As sound waves pass over the top opening of the resonators , the inside air will begin to resonate at a resonance frequency . This will essentially reduce the energy level of that frequency and reduce the decibel level heard on the other side . The length of the resonator neck among others determines the resonance frequency of a respective resonator cell . As the resonator neck extends into the resonating chamber, the resonator neck and the resonating chamber are positioned at the same level . Therefore , the thickness of the acoustic sound panel according to the invention is determined by the thickness of the front and back substrate , and the height of the core plate . Therefore , the acoustic sound panel according to the invention has as an advantage that it has a decreased thickness in comparison to the known acoustic sound panel .

[0012] Additionally, a further advantage may be that the acoustic sound panel according to the invention causes a paradigm shi ft in soundproofing, in particular in the aviation industry, focusing on enhancing the sound absorption capabilities rather than adding dedicated materials .

[0013] A further advantage may be that the resonator cells are decoupled from the back substrate and the front substrate due to the resonator neck extending into the resonating chamber . This may be advantageous as it may allow for an independent design of the core plate and the back and / or front substrate .

[0014] Yet another advantage may be that the one or more support columns reduce the unsupported span of the front substrate and the back substrate , thereby increasing the critical buckling load of the acoustic sound panel .

[0015] In an embodiment, the core plate has a plate height , and wherein the resonator necks extend into the resonating chamber over a neck length, and / or the resonator neck extends substantially traverse to the front substrate . In an embodiment thereof , the neck length is smaller than the plate height . The inventor has surprisingly found that the defined neck length advantageously result in good sound absorption capabilities of the acoustic sound panel , and / or allows the acoustic sound panel to be a single layer acoustic sound panel .

[0016] In an embodiment , at least a part of the resonator necks of the at least a part of the plurality of resonator cells have varying neck lengths and / or varying cross-sectional areas , and / or wherein the volume of the plurality of resonator cells varies with respect to each other . The resonance frequency of the resonator cells is determined among others by the volume of the resonating chamber and the neck length of the resonator neck of a respective resonator cell . By providing the at least a part of the plurality of resonator cells with varying neck lengths , the at least a part of the plurality of resonator cells has varying resonance frequencies . By providing resonator cells with varying resonance frequencies , the energy levels of the varying frequencies and the decibel level heard on the other side are reduced over a range of resonance frequencies . This is advantageous , as the acoustic sound panel according to this embodiment is tuned to dif ferent frequencies , thereby creating broad-spectrum sound absorption .

[0017] In an embodiment, each of the resonator necks is determined by a neck structure arranged within the respective resonator cell . In an embodiment thereof , the neck structure comprises one or more neck walls arranged at opposite walls of the respective resonator cell , wherein the one or more neck walls define an opening therebetween . Preferably, the one or more neck walls have a wall height , wherein the wall height determines the neck length of the respective resonator neck . According to an example , the neck structure has a first neck wall and a second neck wall arranged parallel and opposite to each other, wherein the first and second neck walls are arranged at opposite walls of the respective resonator cell and wherein an opening is provided between the first and second neck walls .

[0018] In an embodiment , the neck structure is provided as a neck structure insert that is configured to be inserted into the resonator cells . In an embodiment thereof , the neck structure insert comprises one or more neck walls that are connected to each other, wherein the one or more neck walls define an opening therebetween . According to an example, the neck structure insert comprises a first neck wall and a second neck wall arranged parallel and opposite to each other, wherein an opening is provided between the first and second neck walls , and wherein the first and second neck walls are connected to each other by means of a connecting wall arranged at the end of the first and second neck walls . The inventors has surprisingly found that by providing the neck structure as a separate neck structure insert that my be inserted into one or more resonator cells of the core plate results advantageously in an acoustic panel with a relatively low weight , which is in particular advantageous in the field of aviation . This is caused by the walls of the resonator cells requiring less sti ffness , so that they may have thinner walls , as the neck structure insert contributes to the structural integrity of the core plate and, thus , of the acoustic sound panel .

[0019] In an embodiment , the one or more support columns in each of the number of the plurality of resonator cells extend between the back substrate and the front substrate and spans the height of the respective resonator cell . In an embodiment , the one or more support columns are connected to at least one of the one or more neck walls of the neck structure , in particular to the side thereof facing away from the opening defined therebetween . Preferably, in each resonator cell with one or more support columns , the one or more support columns are equally spaced from the wall of the respective resonator cell . The support columns are reducing the unsupported span of the back substrate over the respective resonator cell . This is advantageous , as this results in an increased critical buckling load .

[0020] In the context of the present patent application, it is noted that buckling may be understood as a sudden change in shape, i . e . deformation, of a structural component under a load . The critical buckling load may be understood as a compressive load required j ust to initiate such sudden change in shape .

[0021] In an embodiment, the resonator cells have a cross-sectional shape selected from the group comprising a polygon with a finite number of sides , such a hexagonal , and a polygon with an infinite number of sides , such as circular or elliptical , when seen in a direction perpendicular to the core plate .

[0022] In an embodiment, neighboring resonator cells are decoupled from each other . In an embodiment thereof , neighboring resonator cells have one or more j oint edges and / or non-resonant elements therebetween . In light of this embodiment, it is noted that the inventor has surprisingly found that i f a boundary between neighboring resonator cells is too weak, this may result in resonator coupling . Resonator coupling involves interaction between the neighboring resonator cells , and dramatically complicates the tuning process and affects the performance of the acoustic sound panel negatively . According to this embodiment, edge contact between neighboring resonator cells is allowed, wherein edge contact advantageously is suf ficient to prevent resonator coupling from occurring .

[0023] In an embodiment , each of the resonator cells has one or more cell walls for defining the resonating chamber . In an embodiment thereof , the one or more cells walls of neighboring resonator cells are decoupled from each other .

[0024] In an embodiment, the core plate comprises a honeycomb structure having a plurality of honeycomb cells , wherein a part of the plurality of honeycomb cells is a resonator cell . An advantage of using a honeycomb structure as the core plate is that the honeycomb structure advantageously provides a good combination of lightweight, energy absorption, and high required stif fness and / or strength .

[0025] In an embodiment , the honeycomb cells are of fset with respect to each other so that contact between neighboring honeycomb cells is maintained only at the corners thereof . According to this embodiment , the honeycomb cells are translated along their edges until contact between neighboring cells is only maintained at the corners thereof . This results in a topology having hexagons and triangles , which advantageously provides a sti ffer geometry in comparison to a known honeycomb structure .

[0026] A further advantage of this embodiment may be that the density of resonator cells may be signi ficantly increased in comparison to a known honeycomb structure in which neighboring resonator cells are decoupled from each other . For example , this embodiment may result in a fill ratio of more than 75% .

[0027] In the context of the present patent application, the fill ration may be understood as the number of honeycomb cells functioning as a resonator cell with respect to the total number of honeycomb cells .

[0028] In an embodiment , the honeycomb cells are hexagonal shaped, when seen from the front and / or back .

[0029] In an embodiment, the core plate comprises a plurality of hexagonal cells , wherein the resonator cells are arranged around the edge of the hexagonal cells and a quadrangular shaped when seen from the front and / or back, such that a hexagon tessellation is achieved . This is an alternative arrangement of the resonators cells with respect to the known honeycomb structure . An advantage of this embodiment is that is has an increased fill ratio with respect to the known honeycomb structure .

[0030] In an embodiment , the resonator cells are arranged in a square grid configuration . According to this embodiment, the resonator cells are placed similarly to a chessboard, which advantageously allows for an efficient distribution of resonator cells due to the simplicity of the square-grid configuration .

[0031] A further advantage of this embodiment may be that the density of resonator cells may be increased in comparison to a known honeycomb structure in which neighboring resonator cells are decoupled from each other . For example, this embodiment may result in a fill ratio in the range of 40% - 50% , in particular in the range of 45% - 50% . In an embodiment, the front substrate is provided with a filter arranged at the side thereof facing away from the core plate , wherein the filter is configured for shielding the resonator cells from contamination . In an embodiment thereof , the filter comprises a layer of foam, paper and / or fabric arranged at the front substrate, in particular at the side thereof facing away from the core plate . During use of the acoustic sound panel , particulate material may gradually accumulated into the resonant chambers , for example, over the operational li fespan of an aircraft . As Helmholtz resonators rely on open volume, resulting in a susceptibility to dust and debris . Intrusions within the resonance chamber reduce the available volume and influence wave propagation unpredictably . The filter layer advantageously appears to be an effective in shielding the resonator cells from contamination .

[0032] In an embodiment, the back substrate and / or the front substrate are manufactured from a composite material . In an embodiment thereof , the composite material is selected from a group comprising fiberglass , flax fiber and carbon fiber . An advantage of this embodiment is that this described materials seems to be effective in sound adsorption in the acoustic sound panel according to this embodiment .

[0033] According to a second aspect , the invention provides for a neck structure insert for use in an acoustic sound panel according to the first aspect of the invention, and as defined according to the first aspect of the invention .

[0034] The various aspects and features described and shown in the speci fication can be applied, individually, wherever possible . These individual aspects , in particular the aspects and features described in the attached dependent claims , can be made subj ect of divisional patent applications . BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The invention will be elucidated on the basis of an exemplary embodiment shown in the attached drawings , in which :

[0036] Figure 1 shows an isometric view of an acoustic sound panel having a core plate according to an embodiment of the invention;

[0037] Figures 2A - 2B show an isometric view and a top view, respectively, of the core plate of the acoustic sound panel of figure 1 ;

[0038] Figure 3 shows an isometric cross-sectional view of the acoustic sound panel of figure 1 ;

[0039] Figure 4 shows an isometric view of a neck structure insert according to an embodiment of the invention; and

[0040] Figure 5 shows an alternative embodiment of the core plate as shown in figures 2A-2B .

[0041] DETAILED DESCRIPTION OF THE INVENTION

[0042] An isometric view of an acoustic sound panel 1 according to an embodiment of the invention is shown in figure 1 . Such an acoustic sound panel 1 may be used in aircraft structures , for example as cabin lining, in order to absorb sound, for example , coming from the aircraft engines . In this case , the acoustic sound panel 1 reduces noise present within the cabin so that the flying experience of passengers may be enhanced .

[0043] As shown in figure 1 , the acoustic sound panel 1 comprises a back substrate 2 , a core plate 3 and a front substrate 4 , wherein the back substrate 2 , the core plate 3 and the front substrate 4 are arranged such that the core plate 3 is sandwiched between the back substrate 2 and the front substrate 4 . The acoustic sound panel 1 according to the invention, thus , is an acoustic sandwich sound panel 1 .

[0044] The back substrate 2 comprises a face sheet 5 that may be made of a composite material such as fiberglass , flax fiber or carbon fiber . The back substrate 2 is arranged at the back side of the core plate 3 and defines the bottom of the core plate 3 .

[0045] The front substrate 4 also comprises a face sheet 6 that may be made of a composite material such as fiberglass , flax fiber or carbon fiber . As shown in figure 1 , the face sheet 6 of the front substrate 4 is provided with a plurality of through holes 7 , in particular slitshaped through holes 7 , that are evenly distributed across the face sheet 6. The face sheet 6 is arranged at the front side of the core plate 3 and defines the top of the core plate 3 .

[0046] An isometric view and a top view of the core plate 3 are shown in figures 2A - 2B . The core plate 3 comprises a plurality of resonator cells 10 arranged next to each other to form the core plate 3 and in cell lines Lx , L2, ..., Ln. Each resonator cell 10 has a hexagonal shape, when seen from above . The resonator cells 10 within each of the cell lines L2, L2, ..., Lnare arranged with respect to each other so that neighboring resonator cells 10 contact each at one of the corners of each of the neighboring resonator cells 10 . The resonator cells 10 of neighboring cell lines L2, L2, ..., Lnare translated with respect to each other, so that the resonator cells 10 of neighboring cell lines L2, L2, ..., Lnonly contact each other at corners thereof . This has to be understood as that the walls of the neighboring resonator cells 10 are prevented from contacting each other .

[0047] As best shown in figure 2B, the arrangement of the resonator cells 10 results in a plurality of triangles 11 being present between the hexagonal resonator cells 10 . As a result, the core plate 3 has a topology comprises hexagonal resonator cells 10 and triangles 11 . In other words , the topology of the core plate 3 is realized by offsetting the resonator cells 10 of a honeycomb structure .

[0048] Each of the resonator cells 10 defines a resonating chamber 15 therein, which resonating chamber 15 defined an enclosed volume of air . The air enclosed in the resonating chamber 15 is able to resonate at a frequency, preferably a single frequency .

[0049] As shown in figures 2A and 2B, each of the resonator cells 10 is provided with an opening 16, in particular an elongated opening 16, at the side of the respective resonator cell 10 facing towards the front substrate 4 . Each of the openings 16 is defined by a neck structure 17 having a first neck wall 18 and a second neck wall 19 arranged parallel and opposite to each other, wherein the opening 16 is defined by the first neck wall 18 and the second neck wall 19 . Each of the first neck wall 18 and the second neck wall 19, at both ends thereof , is connected to the inner circumference of the respect resonator cell 10 .

[0050] As shown in figure 3 , the first and second neck walls 18 , 19 have a length when seen in the direction from the front substrate 4 towards the back substrate 2 , wherein the lengths of the first and second neck walls 18 , 19 are equal to each other within the respective resonator cell 10 . The length of the first and second neck walls 18 , 19 varies between the plurality of resonator cells 10 , so that a plurality of neck wall lengths are present within the acoustic sound panel 1 . The first and second neck walls 18 , 19 define a resonator neck for allowing sound to enter into the resonator cell ( s ) 10 , in particular an inward directed resonator neck, wherein the length of the first and second neck walls 18 , 19 determine the resonant frequency of the respective resonator cell 10 , which is the frequency at which the resonator cell 10 naturally oscillates . Due to the variety of neck wall lengths within the resonator cells 10 , the acoustic sound panel 1 is configured for resonating at a plurality of sound frequencies .

[0051] As best shown in figure 3 , the through holes 7 are aligned with the openings 16 of the resonator cells 10 such that each of the resonator chambers 15 is open to the outside air via the opening 16 and the associated through hole 7 .

[0052] At the side of the first and second neck walls 18 , 19 facing away from the opening 16 , as shown in figures 2B and 3 , one or more, in particular two , support columns 20 are arranged . The support columns 20 extend between the first and second neck walls 18 , 19 and the back substrate 2 , and are connected thereto . In particular, each of the support columns 20 spans the height of the resonator cell 10 , so that the support columns 20 are also contacting the front substrate 4 . As a result, the first and second neck walls 18 , 19 are connected to the back substrate 2 , and to the front substrate 4 .

[0053] As shown in figure 2B, each of the resonator cells 10 has support columns 20 that are equally spaced from the walls of the respective resonator cell 10 . As a result , as follows from figure 3 , the unsupported span of the back substrate 2 and / or front substrate 4 over each of the resonator cells 10 is signi ficantly reduced, so that the back substrate 2 and / or front substrate 4 is strengthened and the critical buckling load is increased .

[0054] For completeness ' sake , it is noted that buckling may be understood as a sudden change in shape , i . e . deformation, of a structural component under a load . The critical buckling load may be understood as a compressive load required j ust to initiate such sudden change in shape .

[0055] The acoustic sound panel 1 as described in relation to figures 1 - 3 is provided with resonator cells 10 with an integrated neck structure 17 , wherein the neck structure 17 merges into the walls of the resonator cells 10 . Alternatively, the neck structure may be provided as a separate neck structure insert 25 that is configured for being inserted into a resonator cell 10 of a core plate 3 as shown in figures 2A and 2B .

[0056] An isometric view of a neck structure insert 25 according to an embodiment of the invention is shown in figure 4 . The neck structure insert 25 comprises a neck portion 26 having a first neck wall 27 and a second neck wall 28 arranged parallel and opposite to each other . The first and second neck walls 27 , 28 are connected to each other by means of a connecting wall 29 arranged at the ends of the first and second neck walls 27 , 28 . The first neck wall 27 , the second neck wall 28 and the connecting walls 29 together define a neck channel 30 that is open upward and downward, thereby defining a resonating neck .

[0057] It is noted that the height H of the first neck wall 27 , the second neck wall 28 and the connecting walls 29 is equal , but may be varied between separate neck structure inserts 25 so that the di fferent neck structure inserts 25 are tuned to dif ferent resonance frequencies .

[0058] As shown in figure 4 , the neck structure insert 25 is provided with a number of support columns 31 . Each of the support columns 31 is arranged at one of the first and second neck walls 27 , 28 , and extends from the top side thereof , which is the side facing towards the front substrate 4 when inserted, towards and beyond the bottom side thereof . The length of the support columns 31 is chosen such that they span the height of a resonator cell into which the neck structure insert 25 is to be inserted .

[0059] An isometric view of an alternative embodiment of the core plate 3 as shown in figures 2A - 2B is shown in figure 5. The core plate 3 as shown in figure 5 comprises the same features as the core plate as shown in figures 2A - 2B, which features are referred to by the same reference numbers . The core plate 3 as shown in figure 5 di ffers from the core plate of figures 2A - 2B in that the resonator cells 10 have a circular cross-section when seen in a direction perpendicular to the core plate 3 , while the resonator cells 10 as shown in figures 2A - 2b have a hexagonal cross-section when seen in a direction perpendicular to the core plate 3

[0060] It is to be understood that the above description is included to illustrate the operation of the preferred embodiments and is not meant to limit the scope of the invention . From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present invention .

Claims

C L A I M S1 . Acoustic sound panel , comprising : a back substrate , a core plate arranged parallel to and at the back substrate, wherein the core plate is provided with a plurality of resonator cells arranged next to each other, wherein each of the resonator cells defines a resonating chamber therein, and a front substrate arranged parallel to and at the core plate, so that the core plate is sandwiched between the back substrate and the front substrate, wherein at least a part of the plurality of resonator cells of the core plate is provided with a resonator neck for providing a fluid connection between the resonating chamber and the environment, wherein the resonator necks extend into the resonating chambers of the respective resonator cells , wherein the front substrate is provided with a plurality of perforations that are aligned with the resonator necks of the resonator cells , and wherein at least a part of the plurality of resonator cells comprises one or more support columns , wherein the one or more support columns extend at least between the back substrate and the end of the resonator neck facing the back substrate , thereby spanning the height of the respective resonator cell .2 . Acoustic sound panel according to claim 1 , wherein the core plate has a plate height , and wherein the resonator necks extend into the resonating chamber over a neck length, and / or wherein the resonator neck extends substantially traverse to the front substrate .3 . Acoustic sound panel according to claim 2 , wherein the neck length is smaller than the plate height .4 . Acoustic sound panel according to claim 2 or3 , wherein at least a part of the resonator necks of the at least a part of the plurality of resonator cells have varying neck lengths and / or varying cross-sectional areas , and / or wherein the volume of the plurality of resonator cells varies with respect to each other .

5. Acoustic sound panel according to any one of the preceding claims , wherein each of the resonator necks is determined by a neck structure arranged within the respective resonator cell .

6. Acoustic sound panel according to claim 5 , wherein the neck structure comprises one or more neck walls arranged at opposite walls of the respective resonator cell , wherein the one or more neck walls define an opening therebetween .7 . Acoustic sound panel according to claim 6 , when dependent on claim 2 , wherein the one or more neck walls have a wall height , wherein the wall height determines the neck length of the respective resonator neck .8 . Acoustic sound panel according to claim 5 , wherein the neck structure is provided as a neck structure insert that is configured to be inserted into the resonator cells .

9. Acoustic sound panel according to claim 8 , wherein the neck structure insert comprises one or more neck walls that are connected to each other, wherein the one or more neck walls define an opening therebetween .10 . Acoustic sound panel according to any one of the preceding claims , wherein the one or more support columns in each of the number of the plurality of resonator cells extend between the back substrate and the front substrate and spans the height of the respective resonator cell .11 . Acoustic sound panel according to any one of the claims 5 - 9, and claim 10 , wherein the one or more support columns are connected to at least one of the one or more neck walls of the neck structure, in particular to theside thereof facing away from the opening defined therebetween .12 . Acoustic sound panel according to claim 11 , wherein, in each resonator cell with one or more support columns , the one or more support columns are equally spaced from the wall of the respective resonator cell .13 . Acoustic sound panel according to any one of the preceding claims , wherein the resonator cells have a cross-sectional shape selected from the group comprising a polygon with a finite number of sides , such a hexagonal , and a polygon with an infinite number of sides , such as circular or elliptical , when seen in a direction perpendicular to the core plate .14 . Acoustic sound panel according to any one of the preceding claims , wherein neighboring resonator cells are decoupled from each other .

15. Acoustic sound panel according to claim 14 , wherein neighboring resonator cells have one or more j oint edges and / or non-resonant elements therebetween .

16. Acoustic sound panel according to any one of the preceding claims , wherein each of the resonator cells has one or more cell walls for defining the resonating chamber .17 . Acoustic sound panel according to claims 14 and 16, wherein the one or more cells walls of neighboring resonator cells are decoupled from each other .18 . Acoustic sound panel according to any one of the preceding claims , wherein the core plate comprises a honeycomb structure having a plurality of honeycomb cells , wherein a part of the plurality of honeycomb cells is a resonator cell .

19. Acoustic sound panel according to claim 18 , wherein the honeycomb cells are offset with respect to each other so that contact between neighboring honeycomb cells is maintained only at the corners thereof .20 . Acoustic sound panel according to claim 18 or 19, wherein the honeycomb cells are hexagonal shaped, whenseen from the front and / or back .21 . Acoustic sound panel according to claim 17 , wherein the core plate comprises a plurality of hexagonal cells , wherein the resonator cells are arranged around the edge of the hexagonal cells and a quadrangular shaped when seen from the front and / or back, such that a hexagon tessellation is achieved .22 . Acoustic sound panel according to claim 17 , wherein the resonator cells are arranged in a square grid configuration .23 . Acoustic sound panel according to any one of the preceding claims , wherein the front substrate is provided with a filter arranged at the side thereof facing away from the core plate , wherein the filter is configured for shielding the resonator cells from contamination .24 . Acoustic sound panel according to claim 23 , wherein the filter comprises a layer of foam, paper and / or fabric arranged at the front substrate, in particular at the side thereof facing away from the core plate .

25. Acoustic sound panel according to any one of the preceding claims , wherein the back substrate and / or the front substrate are manufactured from a composite material .

26. Acoustic sound panel according to claim 25 , wherein the composite material is selected from a group comprising fiberglass , flax fiber and carbon fiber .27 . Neck structure insert for use in an acoustic sound panel according to any one of the claims 1 - 26, and as defined in any one of the claims 1 - 26.-o-o-o-o-o- o-o-o-BT / HZ

Images