ES2421461B1 - ACOUSTIC PANEL AND ACOUSTIC CLOSURE - Google Patents

Abstract

Acoustic panel and acoustic enclosure. # Includes a plurality of grooves (2, 2A, 2B, 2C, 2D) on the front face (1a) and a plurality of grooves (3, 3A, 3B, 3C, 3D) on the back side (1b), determining the grooves (3, 3A, 3B, 3C, 3D) of the rear face (1b) a plurality of perforations (4, 4A, 4B) in the panel (1), in the areas of intersection with the grooves (2) of the front face (1a), characterized by the fact that; - said grooves (2, 2A, 2B, 2C, 2D) of the front face (1a) have a width between 2 and 6 mm, a depth between 5 and 11 mm, and are separated a distance between 9 and 14 mm, and - said grooves (3, 3A, 3B, 3C, 3D) of the rear face (1b) have a width between 8 and 12 mm and a depth between 5 and 11 mm, and by the fact that; - the area of intersection of the grooves (3, 3A, 3B, 3C, 3D) of the rear face (1b) with the grooves (2, 2A, 2B, 2C, 2D) of the front face (1a) determines a rate of perforation of the panel (1) equal to or less than 15%, each of the slots (3, 3A, 3B, 3C, 3D) of the rear face (1b) having a percentage of surface free of perforations (4, 4A, 4B) equal to or greater than 75%, so that said slots (3) on the rear face (1b) configure sound absorption cavities (5, 5B) in the panel itself (1, 1A, 1B, 1C, 1D) .

Description

DESCRIPTION

Acoustic panel and acoustic enclosure.

The present invention relates to an absorbent acoustic panel and an acoustic enclosure comprising said acoustic panel.

BACKGROUND OF THE INVENTION

Acoustic panels are known which comprise a plurality of perforations to absorb the sound, which extend from the visible face of the panels to the rear face. These panels are mounted on support profiles that are fixed to the ceilings or walls determining an air chamber that houses behind the panel an absorbent material such as rock wool.

The acoustic absorption coefficient of the panel varies depending on the percentage of perforation, this coefficient being 15 higher the larger the perforated surface of the profile.

Current acoustic enclosures that include absorbent acoustic panels such as those described require the presence of an air chamber to obtain an acceptable acoustic absorption coefficient.

 twenty

However, the provision of the aforementioned air chamber has the disadvantage that it entails a loss of useful space of the enclosure in which the acoustic enclosure is carried out.

On the other hand, fixing the panels in the aforementioned acoustic enclosures is laborious, since it must be carried out preventing the perforations being plugged by the support profiles so as not to diminish the acoustic efficiency.

In addition, when the desired degree of sound absorption is high, panels with high perforation rates should be used which make the panel very fragile.

  30

DESCRIPTION OF THE INVENTION

The objective of the present invention is to solve the aforementioned drawbacks, developing a panel and an acoustic enclosure that have the advantages that will be described below.

 35

In accordance with this objective, according to a first aspect the present invention provides an acoustic absorbent panel comprising a plurality of grooves in the front face and a plurality of grooves in the rear face, the grooves of the rear face determining a plurality of perforations in the panel, in the areas of intersection with the grooves of the front face, the panel being characterized by the fact that;

 40

- said grooves of the front face have a width between 2 and 6 mm, a depth between 5 and 11 mm, and are separated by a distance between 9 and 14 mm, and

- said grooves of the rear face have a width between 8 and 12 mm and a depth between 5 and 11 mm,

and for the fact that; Four. Five

- the area of intersection of the grooves of the back face with the grooves of the front face determines a perforation rate of the panel equal to or less than 15%, each of the grooves of the back face having a percentage of surface free of perforations equal to or greater than 75%, so that said slots on the back face configure sound absorption cavities in the panel itself.

 fifty

Surprisingly, it has been observed that the unperforated area of the grooves of the rear face of the panel determines cavities in the panel itself that provide absorbent properties. Thanks to this, a very effective panel is achieved from the acoustic point of view without the need to resort to a high perforation rate, so, in addition, the panel is very resistant and quick to manufacture.

 55

Another advantage of the claimed acoustic panel lies in the fact that it can be fixed directly on support profiles without losing acoustic efficiency, since the presence of said absorbent cavities compensates for the loss of absorption caused by covering any of the perforations with the support profile. of the panel.

According to the same objective, according to a second aspect, the present invention provides an acoustic enclosure 60 devoid of an air chamber that includes the claimed panel.

Surprisingly, it has been observed that the acoustic panel of the present invention guarantees a good acoustic absorption without resorting to an air chamber, whereby said panel can be mounted directly on a wall or ceiling without losing acoustic efficiency. 65

Thanks to this, an acoustic enclosure devoid of an air chamber is provided, which is very useful for installation in small enclosures in which until now it was not possible to install any acoustic enclosure. In addition, the claimed enclosure has the advantage that it can be adapted to light mobile structures that can be arranged in different places in a room or room to improve its acoustics.

 5

According to a preferred embodiment, preferably the grooves of the back face have a perforation-free surface equal to or greater than 82% and, advantageously, the grooves of the back and front face extend longitudinally in the panel, in an aligned manner, keeping or not a parallel relationship between them.

According to the same preferred embodiment, the grooves of the rear face of the panel advantageously extend longitudinally in the form of sine waves.

It has been observed that the grooves in the form of sine waves allow to configure absorption cavities in the panel that are very effective from the acoustic point of view.

 fifteen

Advantageously, said sine waves are continuous. However, alternatively, said sine waves can be discontinuous. In this way, the panel gains in resistance.

Preferably, said grooves in the form of sine waves are arranged substantially parallel and separated from each other by a distance (x) between 35 mm and 70 mm, this distance (x) being the distance between 20 sines or crests of two adjacent waves.

Again preferably, said sine waves have a wavelength between 30 mm and 50 mm and a wavelength between 40 mm and 60 mm.

 25

Advantageously, the depth of the grooves of the rear face varies along the length of the panel inversely to the depth of the grooves of the front face, so that a half-wavy plane "z" is created inside the panel ", The intersection area of both slots defining the perforations being located, in said wavy plane" z ".

 30

It has been observed that, when the intersection area of both slots is located in said half-wavy plane, the perforations of the panel defined by said intersection area are located at different heights, which significantly improves the acoustic efficiency of said panel, increasing from this forms the mid-frequency absorption much needed in the correction of human speech.

 35

Preferably, said panel comprises at least two longitudinal sections each provided with an average plane of undulation "z1, z2", the direction of undulation of the planes of each of said sections being inverse.

According to one embodiment, the cross-section of the grooves of the front face includes a bottom "d" of width greater than the entrance hole "e". 40

It has been observed that the bottom "d" of greater width allows to increase the perforation rate of the panel, since the internal intersection area of the grooves of the front face with the grooves of the back face and, therefore, the perforation area of the panel itself. In this way, it is possible to expand the perforation rate of the panel without substantially varying its aesthetic appearance. Four. Five

Again advantageously, the grooves of the front face are made of a layer of flame retardant material, preferably a material that includes magnesium.

BRIEF DESCRIPTION OF THE DRAWINGS 50

For greater understanding of how much has been exposed, some drawings are attached in which, schematically and only by way of non-limiting example, several practical cases of realization are represented.

In these drawings, 55

Figure 1 shows a plan view of a first embodiment of the acoustic panel on the exposed face that includes front grooves.

Figure 2 shows a plan view of the acoustic panel of Figure 1 on the hidden side including rear slots 60 in the form of sine waves.

Figure 3 shows a section of Figure 1.

Figure 4 shows a perspective view of the panel of Figure 1 on its hidden face. 65

Figure 5 shows a perspective view of the panel of Figure 1 from its face.

Figure 6 shows a plan view of an embodiment of the panel of Figure 1 which includes posterior grooves in the form of discontinuous sine waves.

 5

Figure 7 is a graphic representation of the practical acoustic absorption coefficient as a function of the sound frequency applied to an acoustic enclosure with an air chamber, which includes the panels of the embodiment of Figures 1 to 5.

Figure 8 is a graphical representation of the practical sound absorption coefficient as a function of the frequency of sound applied to an acoustic enclosure devoid of an air chamber, which includes the panels of the embodiment of Figures 1 to 5.

Figure 9 shows a cross section analogous to that of Figure 3 of a second embodiment of the panel. This figure 9 includes a detail showing the cross section of the front grooves. fifteen

Figure 10 shows a plan view of a third embodiment of the panel in which the depth of the grooves varies along the length of the panel.

Figures 11 and 12 show two longitudinal sections of the panel of Figure 10. 20

Figure 13 shows a plan view of a fourth embodiment of the panel provided with non-parallel front grooves.

Figure 14 shows a plan view of the embodiment of Figure 13 from the sine wave face. 25

Figure 15 shows a plan view of a fifth embodiment of the panel provided with circular grooves.

Figure 16 shows a plan view of the embodiment of Figure 15 from the sine wave face.

 30

DESCRIPTION OF VARIOUS PREFERRED EMBODIMENTS

Several embodiments of the panel of the present invention are described below which include slots 3,3A, 3B, 3C, 3D on the back side in the form of sine waves.

 35

As the figures show, the panel 1,1A, 1B, 1C, 1D of the present invention includes a plurality of front slots 2,2A, 2B, 2C, 2D extending on the front face 1a, and a plurality of slots 3,3A, 3B, 3C, 3D posteriors that also extend on the rear face 1b of panel 1,1A, 1B, 1C, 1D, in the form of sine waves.

 40

The intersection areas of the posterior slots 3,3A, 3B, 3C, 3D with the front slots 2,2A, 2B, 2C, 2D determine a plurality of perforations 4,4A, 4B intended to absorb acoustic energy.

However, as described, in panel 1,1A, 1B, 1C, 1D of the present invention the perforated area never exceeds 15% of the total surface area of panel 1,1A, 1B, 1C, 1D, each of the grooves 3,3A, 3B, 3C, 3D of the rear face having a percentage of perforation-free surface area equal to or greater than 75%, so that said grooves of the rear face configure cavities 5.5B absorption of sound on the panel itself.

Thanks to this, the 1,1A, 1B, 1C, 1D panel of the present invention is very effective from the acoustic point of view without resorting to a high perforation rate, so it is very resistant and quick to manufacture. fifty

Another advantage of panel 1,1A, 1B, 1C, 1D of the present invention lies in the fact that it guarantees good acoustic absorption without the need to use an air chamber, whereby said panel 1,1A, 1B, 1C , 1D can be mounted directly on a wall or ceiling without losing efficiency.

 55

Thanks to this, an acoustic enclosure devoid of an air chamber is provided, which is very useful for installation in small enclosures in which until now it was not possible to install any acoustic enclosure.

A comparative test of acoustic absorption in a reverberant room according to the UNE-60 EN ISO 354: 2004 standard of a sample of panels 1 of the present invention mounted with and without an air chamber is described below.

In the test carried out, panels 1 are composed of 16 mm thick medium density fiberboard (DM) chipboard, covered with a 1 mm bamboo sheet on its front face 1 and a self-adhesive black glass fiber veil your back face 1b. 65

The panels tested are those shown in the attached figures 1 to 5. These panels 1 have front slots 2 with a width of 3.2 mm, a depth of 9 mm, which are separated from each other a distance of 11.7 mm. The rear slots 3, in the form of continuous waves, have a width and depth of 8 mm, a wavelength of 43.3 mm, a wavelength of 49.6 mm, and are separated from each other a distance of 38 mm, this distance being the distance (x) between sines or crests of two contiguous waves 5. The perforation rate of the panels 1 tested is 10%, with the subsequent grooves 3 having a percentage of surface area without perforations of 76%.

The panels 1 are mounted on 40 mm wooden battens that create enough space to house a rock wool of the same thickness and density of approximately 40 Kg / m3. 10

The test was carried out with panels 1 mounted in two different configurations:

- Directly on a reflective surface with a layer of mineral wool 40 mm thick (test without air chamber).

- With an air chamber 40 cm deep with a layer of mineral wool 40 mm thick (test with 15 air chamber).

In the test without an air chamber, the panels 1 have been placed directly on the floor of the test room by sealing the sides of the entire sample by a reflective wooden perimeter frame, in order to prevent the passage of acoustic energy through the sides of the sample and act only the upper face. twenty

In the air chamber test, panels 1 have been placed on supports to create a 40 cm deep chamber between the rock wool and the floor of the test room. Likewise, the sides of the sample have been sealed by a reflective wooden perimeter frame, in order to prevent the passage of acoustic energy through the sides of the sample and that only the upper face acts. 25

The measurements made have allowed the calculation of the practical acoustic absorption coefficient p and the weighted acoustic absorption coefficient w of panels 1, as well as assigning a sound absorption class to panels 1 (see attached results and figures 7 and 8).

 30

CHAMBER TEST RESULTS

image 1

image2

CHAMBER-FREE TEST RESULTS

image3

image4

The practical sound absorption coefficient is a value dependent on the frequency of the sound, based on 5 measurements by bands of one third of an octave according to ISO 354. As for the weighted sound absorption coefficient, it is a unique value independent of the frequency, equal to the value of the reference curve at 500 Hz after moving it towards the practical sound absorption value curve. This weighted sound absorption value is used to calculate the sound absorption class.

 10

The analysis of the results and figures shows that the weighted acoustic absorption coefficients are greater than 0.70 in both tests; specifically of 0.75 in the test without camera, and 0.85 in the test with camera. It is also observed that, in the 500 Hz and 1000 Hz frequency bands, the practical absorption coefficients are greater than 0.80, both in the chamber and without chamber tests.

 fifteen

In view of the results, it is possible to affirm that the panels of the present invention guarantee excellent acoustic efficiency whether they are mounted with or without an air chamber, and that said efficiency is particularly relevant in very significant frequency bands such as those of the human speech

Thanks to this, the panels of the present invention are useful for installing in enclosures of reduced dimensions in 20 which until now it was not possible to install an acoustic enclosure because of the lack of space to provide an air chamber.

On the other hand, in both cases, the acoustic panels 1 used have a perforation rate of less than 15%, so that the acoustic efficiency is achieved without affecting the overall resistance of the panels 1. 25 In addition, the panels 1 are very easy and quick to manufacture, since the rear slots 3 can be machined by milling.

Referring to Figure 9, this figure shows an embodiment of panel 1A in which the cross-section of the grooves 2A of the front face includes a bottom "d" of width greater than the entrance hole "e". Specifically, in the embodiment shown in Figure 9, the width of the bottom "d" is designed to be 5 mm and the width of the hole "e" is 3 mm.

As mentioned in the description of the invention, this embodiment has the advantage over the embodiment shown in Figure 3, which allows to increase the perforated area of panel 1A and, therefore, its perforation rate and its acoustic efficiency, without the need to substantially vary its aesthetic form.

Figures 10, 11 and 12 show a third embodiment of the panel 1B provided with two longitudinal sections in which the depth of the grooves 3B of the rear face varies along the length of the panel 1B inversely to the depth of the grooves 2B of the front face, so that inside the panel 1B two planes 40 wavy means "z1, z2" of different sense of undulation are created.

As can be seen in the sections of figures 11 and 12, the intersection area of both slots 2B, 3B is located in the undulating planes "z1, z2", whereby the perforations of panel 1B defined by said area of intersection are located at different heights. Thanks to this, the acoustic efficiency of panel 1B is still superior. Four. Five

Figures 13 to 16 show two more embodiments of panel 1C, 1D which constitute two design variations that maintain the same acoustic efficiency characteristics as those of the panels of the aforementioned embodiments.

 5

In the embodiment of Figures 13 and 14, both the slots 2C of the front face and the slots 3C of the back face are kept aligned coinciding in the same direction. However, as can be seen in the same figures, the mentioned slots 2C, 3C do not maintain a parallel relationship. This design is suitable for creating circular structures that resemble a dome.

 10

In the embodiment of Figures 15 and 16, both the 2D front slots and the 3D sinusoids are circular.

Although a specific embodiment of the present invention has been described and represented, it is clear that the person skilled in the art will be able to introduce variants and modifications, or replace the details with other technically equivalent ones, without departing from the scope of protection defined by the claims. attached. fifteen

For example, although reference has been made herein to panels 1,1A, 1B, 1C, 1D with front slots 2,2A, 2B, 2C, 2D that are substantially equidistant from each other, the same slots may not be equidistant and be separated between them variable distances. Similarly, although embodiments with subsequent slots 3,3A, 3B, 3C, 3D in the form of sine waves have been described, the same results could be obtained with slots 20 of similar dimensions that would have other shapes. Similarly, despite the fact that panels 1 consisting of chipboard covered with a bamboo sheet on its front face have been used for the tests, the same acoustic results could be obtained with panels covered with sheets that include fire retardant materials, such as for example magnesium

Claims (12)

1. Acoustic absorbent panel (1,1A, 1B, 1C, 1D) comprising a plurality of grooves (2,2A, 2B, 2C, 2D) on the front face (1a) and a plurality of grooves (3,3A, 3B, 3C, 3D) on the rear face (1b), the grooves (3,3A, 3B, 3C, 3D) of the rear face (1b) determining a plurality of perforations (4,4A, 4B) on the panel ( 1), in the areas of intersection with the grooves (2) of the front face (1a), characterized by the fact that; 5 - said grooves (2,2A, 2B, 2C, 2D) of the front face (1a) have a width between 2 and 6 mm, a depth between 5 and 11 mm, and are separated by a distance between 9 and 14 mm, and - said grooves (3,3A, 3B, 3C, 3D) of the rear face (1b) have a width between 8 and 12 mm and a depth between 5 and 11 mm, 10 and for the fact that; - the area of intersection of the grooves (3,3A, 3B, 3C, 3D) of the rear face (1b) with the grooves (2,2A, 2B, 2C, 2D) of the front face (1a) determines a rate of perforation of the panel (1) equal to or less than 15%, each of the grooves (3,3A, 3B, 3C, 3D) of the rear face (1b) having a percentage of surface free of perforations (4,4A, 4B) equal to or greater than 75%, so that said slots (3) on the rear face (1b) configure cavities (5.5B) for sound absorption in the panel itself (1,1A, 1B, 1C, 1D ). 2. Panel according to claim 1, wherein said grooves (3,3A, 3B, 3C, 3D) of the rear face (1b) extend longitudinally on the rear face (1b) of the panel (1,1A, 1B, 1C, 1D) in the form of sine waves.  twenty 3. Panel according to claim 2, wherein said sine waves are continuous. 4. Panel according to claim 2, wherein said sine waves are discontinuous. 5. Panel according to any of claims 2 to 4, wherein said grooves (3,3A, 3B, 3D) in the form of sinusoidal waves 25 are arranged substantially parallel and separated from each other a distance (x) between 35 mm and 70 mm, this distance (x) being the distance between breasts or crests of two contiguous waves. 6. Panel 1 according to any of claims 2 to 5, wherein the sine waves determining said slots (3,3A, 3B, 3C, 3D) have a wavelength between 30 mm and 50 mm and an amplitude of 30 wave between 40 mm and 60 mm. 7. Panel according to any of the preceding claims, wherein the depth of the grooves (3B) of the rear face (1b) varies along the length of the panel (1B) inversely to the depth of the grooves ( 2B) of the front face (1a), so that a corrugated medium plane (z) is created inside the panel, the intersection area of both slots (2B, 3B) defining the perforations (4B) being located in said wavy plane (z). 8. Panel according to claim 7, comprising at least two longitudinal sections each provided with an average plane of undulation (z1, Z2), the direction of undulation of each of said sections being inverse.  40 9. Panel according to any of the preceding claims, wherein the cross-section of said grooves (2A) of the front face (1a) includes a bottom (d) of width greater than an inlet hole (e). 10. Panel according to any of the preceding claims wherein the grooves (2) of the front face (1a) are made of a layer of flame retardant material, preferably a material that includes magnesium. Four. Five 11. Acoustic enclosure comprising an acoustic panel (1,1A, 1B, 1C, 1D) according to any of the preceding claims, characterized in that it is devoid of an air chamber. 12. Enclosure according to claim 11, comprising an acoustic absorbent material between said acoustic panel 50 (1,1A, 1B, 1C, 1D) and a wall or ceiling on which the panel (1,1A, 1B, 1C) is mounted , 1D) acoustic.