EP2015291B1 - Acoustic elements - Google Patents

Abstract

The element (25) has a support element (27) with recess (28) for accommodation of a sound absorber (26) so that a surface of the recess constitutes 20 to 50 percentages of an upper surface (32) of the support element. The absorber includes an acoustically effective open surface formed by a micro perforation, a micro slot, micro slits (31) or combination. The open surface corresponds to 10 percentage of a total area of an upper surface of the absorber. The absorber is formed as a single element or a sandwich construction or without non-woven material. The absorber is made of glass material, acrylic glass, flat glass, float glass, polished glass, laminate safety glass, toughened glass, special purpose glass, metal, plastic or wood. An independent claim is also included for a method for production of sound absorbing acoustic element.

Description

The present invention relates to acoustic elements according to the preamble of independent claim 1 and to methods for producing acoustic elements according to the preamble of patent claim 10.

For years, the applicant has successfully produced and distributed acoustic elements with sound-absorbing properties from large-area, plate-shaped bodies which are provided with a multiplicity of holes or slots in order to allow the passage of the sound to be absorbed to sound-absorbing insulating materials arranged behind the plate-shaped bodies. These plate-shaped elements are often made of wood, pressboard, multi-component fiber materials, gypsum or plastics and must comply with the applicable regulations for the construction sector, for example in terms of resistance to breakage and fire protection. The common materials for the production of acoustic elements are practically exclusively opaque and the number and arrangement of holes and / or slots, as well as the use of the often fibrous insulation materials restricts architects and builders in the design freedom considerably. On the one hand, the architecture requires open spaces and increased use of hard building materials such as exposed concrete and glass for sound absorbers, which reduces the reverberation time without breaking clear and transparent building structures. There is therefore a need for transparent or at least translucent acoustic elements that are not inferior to the known in terms of functionality and practicability.

In the DE4315759 For example, it is described that conventional passive sound absorbers using porous or fibrous material to convert airborne sound vibrations by friction on their finely structured, as open as possible surface structure into heat (passive absorber) or so-called reactive absorber in which by resonating Foils, plates or membranes the sound energy is removed in a relatively broad frequency band, to replace by sound absorbers of mechanically and chemically highly resistant ceramic materials, which are also transparent.

The in the DE4315759 proposed absorber consist exclusively of one or more completely transparent plates, which are hardly excitable by airborne sound waves. They are enabled by a multitude of very small continuous holes in their space-facing surface in conjunction with a cavity arranged behind them for the absorption of incident sound waves in a wide frequency range in the audible range. The use of such micro-perforated plates before a reverberant limitation to the sound absorption was of D.-Y. Maa already 1975 in Scientia Sinica 18, H. 1, P. 55 to 71 described. In the DE4315759 It is disclosed that the holes can be made by means of a drill, laser or plasma welding machine. There are plane-parallel, provided as directly as possible in front of the reflective glass components retrofitted sound absorbers that do not affect the architectural design. For rooms with predominant voice performances, these flat, transparent absorbers have an absorptivity of greater than 0.5 at 500 Hz near 1, especially for vertically incident sound waves in the frequency range between f = 125 and 1250 Hz. Highly resistant plastics as well as glass are proposed as ideal building materials for such sound absorbers, but also acrylic glass (crystal clear or colored) in the interior area. It is stated that it can develop quite amazingly broadband sound absorbers, if you attach plates made of this material in a thickness between about t = 2 and 12 mm with a distance between D = 25 and 100 mm in front of the glass component, you need no porous or fibrous materials, but only relatively small holes with diameters d from 0.4 to 0.8 mm. In multilayer constructions can be according to patent application DE 4312886 In this way, build resonance absorbers that absorb more than 80% of the entire frequency range of interest on one and the same absorber surface. Until now, a sophisticated technology for microperforating is missing for glass components.

In addition to reducing the reverberation time, the requirements for transparent absorbers in rooms are incombustibility, scratch resistance, mechanical strength and safety against damage from broken glass. Although safety glasses are known, the drilling of a large number of very small through holes, in the order of about 40,000 holes or more per m ² and a diameter of 0.2 to 0.8 mm is technically and above all economically in such Glasses not available yet. Glass as an amorphous solid is particularly susceptible to stress cracking, which is particularly susceptible to rapid drilling or cutting through a 2 to 12 mm thick plate. The safety requirements due to chemical or thermal tempering of the glasses or through laminated safety glass remain unresolved.

In the unpublished application EP 07405023.8 The applicant describes methods for creating microperforations and micro-slits by means of abrasive waterjet technology in glass plates. These methods make it possible to apply holes with a diameter of 0.2 to 0.8 mm in glass sheets on systems with a plurality of nozzle heads by means of abrasive water jet technology. A process control has been developed which minimizes the risk of destruction of the glass sheets to be perforated at the beginning of the perforation process. It has been recognized that a) even a small risk per hole in creating 40,000 continuous microholes results in a tremendous scrap rate and is not economically viable; and b) process safety in a forced stop-and-go operation at such a high cost C) the drilling times in this "stop and go" operation are considerably too long with all methods known today to perforate larger glass components within a reasonable time.

Since, during the drilling through of laminated glass with an internal plastic membrane, the water jet temporarily becomes blurred as it passes from the glass to the elastic plastic membrane, resulting in unwanted cavities in the boundary region of the glass layers to the plastic, which in turn will lead to undesired optical effects and turbidity, in the EP 07405023.8 proposed to slit or cut the glasses after successful piercing by means of the abrasive jet of water with a greatly reduced risk of destruction. The unwanted cavity formation in the area of the plastic film in the case of laminated glass does not remain after cutting after cutting and the width of the micro-slits can be reduced to 0.1 mm, in contrast to the diameter of the holes. Instead of the multiplicity of holes or microperforations, a significantly reduced number of slots are made in the glass.

The advantages of such a micro-slotted sound absorber in glass are that the turbulence and friction of the air in the microslit, with variable cavity arranged therebehind and soundproof boundary increases by any variation of the slot length and slot width and by the arbitrary arrangement of micro-slots in the surface production technology extremely efficient or can be reduced. The sound energy is converted into heat energy in adjustable frequency ranges and the reverberation time is reduced over a wide frequency range. The required open area in the glass, to the extent of approximately 0.8 to 3.0% of the sound area, can be produced by suitable cutting processes with sufficient process reliability and with a 10 times shorter machining time compared to bores. The risk of microcracks can be reduced by controlled slitting as opposed to microhole drilling. By an obvious reduction, the "stop and go" losses, the productivity can be substantially increased.

The WO 2006/021605 A1 describes an acoustic element which is used to absorb acoustic waves and is an alternative to fiber materials and porous materials. The inventive acoustic element is constructed of microperforated insertion (MIUs), which are used in recesses of a support plate.

The BE 647012 proposes a sound-absorbing cladding made of glass or ceramic. In the sound-absorbing panel is a two-piece constructed acoustic element, which consists of a perforated support plate with acoustically active damping elements. Both parts can be made of glass or ceramic. The damping elements are inserted into recesses of the perforated support plate.

The DE 2434768 A1 discloses an acoustic panel and a method of making the same. The acoustic panel is an acoustic element made of transparent plastic. 5% of the surface of the plastic is provided with recesses, these recesses are partially or completely filled by open-cell plastic. The plastic plate acts as a support plate. The open-celled plastic used in the recesses has sound-absorbing properties.

Sound absorbing absorbers designed as microperforated insertion units (MIU) are also used in Applied acoustics: J. Pfretzschner et al. , "Microperforated insertion units: An alternative strategy to design microperforated panels". There are proposed two-part microperforated inserts proposed, the first part has a large wall thickness with large perforations and the second part has a much lower wall thickness with a higher perforation rate.

For the acoustic elements applies in the interior area with personal residence the requirement of splinter freedom. Applying micro holes or micro-slots with an open area of more than 1% directly into carrier glass plates often causes chipping and shells in the glass, so that the carrier glass can not be used as ESG or VSG. The multitude of small micro-holes and narrow micro-slots with an open area of more than 1% also makes the carrier glass unstable statically. Since today in architecture large-scale Acoustic elements are required in which the formats of 1 m ^{2 are} exceeded, the carrier glasses must be correspondingly large format. As a result, glasses provided directly with microperforations or micro-slits become uneconomical. The processes in direct carrier glass processing are unmanageable due to the large number of micro-interventions and the expected failure considerably. It is therefore already in the EP 07405023.8 suggested that in certain embodiments, rondelike micro-slit components are inserted into corresponding openings cut in a base plate. It is proposed to provide the cut-out circular disks or roundels in a separate machining process from the outer periphery with micro-slots, so that a central web is formed, which carries the teeth of two combs. These comb discs are then inserted back into the base glass pane, respectively glued. They can also be used with separate holders releasably or firmly in the respective openings. The resulting rondelles when creating the receiving openings can also be discarded, so that in the openings comb discs from separate production can be used. The creation of the receiving openings does not have to be done with a micro-cutting process, but can be done with conventional methods with sufficient tolerance. The receiving openings can even be attached during the production of the glass panes. The edges of the receiving openings need not be sharp, unlike the edges of the micro slots.

In the EP 07405023.8 It is also disclosed that in order to increase the mechanical stability and in particular when using panes of safety glass two-part glass bricks are used. The base plates made of glass are provided as described above with larger holes / receiving openings and equipped with prefabricated micro-slit glass inserts. The active in the absorption inserts can according to the EP 07405023.8 in other preferred embodiments of the invention in different strengths of glass, but also of other materials such as art glass, other plastics or metal. The micro-slotted inserts are as already mentioned Inserts, holders or adhesions fitted into the receiving openings of the base glass plate. Although these non-glass inserts can also be produced using abrasive water jet technology, they can also be produced using other known cutting or punching methods, in contrast to glass.

In particular, in the embodiments in which the absorption inserts are held by means of inserts or holders in the receiving openings, the risk of injury and the risk of breakage is reduced to a minimum, since the holding force can be adapted to the stability of the absorption insert. If someone hits or pushes against the insert, it will be released from the base plate before it breaks. This advantage is especially useful for inserts made of glass.

It is the object of the present invention to provide alternative components for sound absorbers and methods for producing the same, which make it possible to produce such products efficiently in larger quantities and dimensions and do not have the abovementioned disadvantages. It is a further object of the invention to provide acoustic elements which have excellent sound-absorbing properties, meet all safety requirements in the construction sector, if desired at least partially translucent (translucent) or partially transparent (translucent) and can be produced quickly and economically with reasonable technical effort are and avoid other disadvantages of the known acoustic elements.

These objects are achieved according to the invention by the acoustic elements according to claim 1 and the manufacturing method according to claim 10, advantageous embodiments result from the dependent claims.

The acoustic elements according to the invention can be optimized for a wide variety of absorption requirements and at the same time fulfill the requirement of at least partial absorption Transparency or translucency. According to preferred embodiments, the acoustic elements according to the invention, in particular the absorbers of the acoustic elements, are designed such that they are particularly well suited in the speech range from 125 Hz to 1250 Hz. The new acoustic elements comprise at least one support element with at least one, preferably a plurality of recess which receive respectively decoupled sound-absorbing absorber. In order to achieve the desired transparency and / or translucency, the support element is made of glass or art glass, preferably made of flat glass, float glass, mirror glass, laminated safety glass, toughened safety glass or special glass. In the recess, the acoustically active absorber are used, respectively, according to further embodiments arranged in front of these. The area occupied by the at least one recess in the support element depends on the type and construction of the absorber. It has been found that for a first group of absorbers comprising microperforations, micro-slots, micro-gaps or a combination thereof, the proportion in the support element is about 10 to 60%, advantageously 20 to 50%, based on the total surface area of the acoustic elements should. If the absorption effect of the absorbers is based on passive absorption materials, such as nonwoven products, ie fibrous woven or nonwoven materials, or open-cell foams or expanded building materials, then the acoustically effective area, that is to say those which have broken open in the carrier glass plate and with absorbers equipped area advantageously between 3 to 60%, preferably between 5 to 20%.

While the aforesaid absorbers based on microperforations, microslits and microcolumns are characterized by number, dimensioning or effective open area resulting therefrom, the absorbers based on fibrous, porous or expanded materials are characterized by flow resistance.

This second group of absorbers can have a wide variety of length-specific flow resistances. By adjusting the thickness of the material, the effective flow resistance can be set, which is usefully made according to the achieved specific flow resistance (according to EN 29053). Preferably, these passive absorbers have a specific flow resistance of 500 to 3000 Pa * s / m.

The acoustically absorbent inserts or absorbers of various non-glass materials, such as metal, plastic, wood, membranes, woven and nonwoven fabrics, open cell foams or expanded construction materials, and / or combinations thereof may act as decoupled inserts in glass support members for transparency and absorption as well as absorption and aesthetics. The absorbers can be used natural or dyed.

Unlike glass absorbers, non-glass absorbers can be provided with microperforations or micro-slits made by known methods such as drilling, milling, punching, needling or lasers. These methods can be achieved high open areas, and thus a high acoustic absorption at low manufacturing costs.

It has been found that the open area of the acoustically effective microperforations, micro-slots or micro-gaps plays a significant role in absorption performance. With the adaptation of the corresponding parameters of smaller slot widths and more open area, it became apparent that with the water jet method these specifications can not be achieved or can only be achieved by means of complex additional operations.

For a broadband micro-slotted absorber, slit widths of less than 0.3 mm are required, and at the same time, the open area must be increased to over 3% of the base area of the acoustic element. As an unexpected alternative method of abrasive waterjet cutting Slurry wire sawing has proven itself. With this method, the slot widths compared to the abrasive water jet cutting can be massively reduced and it can achieve slot widths of 0.1 to 0.3 mm. The economically interesting slurry wire sawing process for such dimensions is known from wafer cutting in the semiconductor industry. With this method, not only very narrow slits of up to 0.1 mm can be sawed, but also narrow webs of less than 2 mm in width can be produced without these breaking during sawing. The required performance can be achieved by stacking several glass plates in succession into blocks and simultaneously sawing several blocks.

For this slurry wire sawing process, machinery and equipment such as silicon wafer fabrication are available on the market. By appropriate application adjustments, combed glass inserts can be sawed such that this method can meet the requirements for the efficient production of decoupled inserts with a high density of fine slots, so that the cost of machine investment and, above all, the operating costs of the consumables wire and Separating fluid are justified. The so sawn filigree decoupled elements must first be glued and stabilized for insertion into the carrier glass on three sides, preferably with glass rods.

As an alternative non-inventive method for producing acoustically active absorber elements is now proposed to build absorber elements with micro-columns of individual thin glass rods. The individual rods are preferably rectangular or polygonal and are assembled at intervals of, for example, 0.2 mm into an element and preferably glued, so that micro gaps of 0.2 mm are formed. With a rod width of, for example, 1.8 mm and a distance of 0.2 mm between the rods, absorbers with an open micro-gap area of 10% based on the surface of the absorber element can be produced. It has been shown that the column width is between 0.1 and Should be 0.8 mm. Broader columns show only very unsatisfactory absorption performances. Preferably, the gap widths are 1.5 to 3 mm. The thickness of the rods, and thus the width of the webs, should be chosen between 1 and 8 mm, advantageously between 1.5 and 3 mm. In preferred embodiments, it is selected at 1.8 mm.

From 100 glass rods with a rectangular cross-section and a size of 1.8 mm x 4 mm x 200 mm, which are available on the market, it is possible, for example, to produce absorber elements in the size of 200 x 200 mm with 99 micro-gaps of 0.2 mm width economically efficiently.

The rational non-inventive production of fine glass rods can be done by means of glass scratches and breaking or other known methods such as drawing, pressing or casting. It is essential that the glass surfaces without shells and chipping and preferably remain mirror-like. In the format of the finished glass elements, a frame construction made of glass or art glass is glued so that the fine glass rods receive additional stability, for example through a profile frame. The gluing of the glass rods with gaps, which correspond to the required slot width, is largely fully automatic, by means of a mounting robot. The clam-free glass rods are preferably chemically or thermally cured after calibration, so that these, like the glass carrier plates, meet the passive safety requirements in public and private spaces without splintering. Furthermore, an increase in impact resistance, flexural strength and scratch resistance is achieved. The advantages of this non-inventive construction method over the microperforation or microslot methods are transparent insert elements without turbidity of the edge surfaces, a higher strength of the hardened rods and an increase in the passive safety of the absorber inserts.

The support elements can, as already mentioned above, be produced in various forms, but usually they are formed as plate-shaped components with an approximately plan first surface. In preferred embodiments of the invention, the support elements are carrier glass plates made of flat glass or special glass in thicknesses between 2 and 12 mm, which are provided with recesses for receiving the absorber. The recesses are preferably cut or milled into the glass plates and then, if necessary, chamfered, ground and / or polished, so that they can be easily seked and further processed as needed to tempered safety glass or laminated safety glass.

The erupted surfaces may be regularly or irregularly distributed on the glass carrier surface. The order of magnitude of the areas broken out correlates with the required open area of the absorber elements and with the ratio to the total area. The erupted area to the entire first surface of the carrier glass plate is again between 10% and 60%, advantageously between 20% and 50%. Depending on the application, the glass plate as a carrier element can have different length and width dimensions as well as different glass thicknesses.

The carrier glass can be used in a frame or frameless with appropriate fixtures at the installation site. The inventive acoustic elements can be structurally joined together to form walls, ceilings or cassette elements and can be flat or curved. Support glass as well as the preferably glued acoustically active glass absorber can be colored, etched, foiled or coated.

The absorbers may be distributed homogeneously or irregularly on the surface of the carrier elements and be formed with round, triangular, quadrangular or polygonal, regular or irregular polygonal, rectangular, square or other like base. By maintaining a sufficient edge distance, the absorber can be practically in any arrangement place in the support element. The area occupied by the absorbers in the transparent or translucent support elements is limited to an upper limit of about 60% by the requirement of light transmission and the strength load or the breakage resistance of the acoustic elements. The lower limit, on the other hand, is determined by the absorption power in the frequency range to be absorbed. In order to achieve particularly good absorption performance in a wide frequency range, for example in the speech range from 125 Hz to 1250 Hz, according to the first embodiments of the invention, absorbers are used in which the acoustically effective open surface is formed by microperforations, micro-slots, micro-gaps or a combination thereof , this acoustically effective open area corresponding to 1 to 12%, preferably 7 to 12%, particularly preferably 10% of the total area of a first surface of the absorber. It is possible to combine both different absorption elements with microperforation, micro-slots or micro-gaps in a support element, or microperforations, micro-slits and / or micro-gaps can be combined within an absorber. Both microperforations, micro-slots and micro-gaps can be used with different diameters and / or widths in the same or in different absorbers. The widths can also be varied within a micro-slot or within a micro-column.

The absorbers can be produced as single elements or as sandwich constructions with or without nonwoven material. All these combination possibilities make it possible to widen the bandwidth of effectively absorbed sound frequencies. It has been shown in experiments that different slot and gap widths and different hole diameters and single elements or sandwich constructions have absorption maxima in different widths in different frequency ranges. For example, in addition to single-layer multilayer glass structures with micro-gaps, they are joined together to form sandwich constructions. Such a multilayer structure results in additional resonators, which amplified the absorption and broadened the frequency range. This results in a total broadband absorber.

According to preferred embodiments, the absorbers are produced slot-free. In the non-glass materials, absorbers with microperforations or absorbers with acoustically active fibrous woven or nonwoven materials, open cell foams or expanded building materials have proven particularly advantageous in the production. In the case of absorbers made of glass materials, it has proved to be advantageous, particularly with regard to production, to use absorbers with microcolumns, which are likewise slot-free.

Like the single-layer absorbers, the sandwich constructions are arranged in the recesses of the carrier material, in particular the carrier glass, flush or superimposed, in particular adhesively bonded or held non-positively and / or positively.

In order for the above-described acoustic elements with single-layer absorbers, in particular the plate-like elements, to function, their assembly is distanced from a reverberant rear wall. The acoustic elements according to the present invention are mainly used for use as attachment elements or for installation in cassettes. When used as facing shells or attachment elements, the acoustic elements are mounted at a distance of 5 to 350 mm, preferably at a distance of 10 to 100 mm, spaced from ceilings, walls, windows, doors and / or other reverberant surfaces. In structural variants for the production of cassettes, cylinders, cuboids and profiles, they are mounted in front of a correspondingly designed rear wall or can be used, for example, as free-standing acoustic elements or room dividers.

Brief description of the figures

Fig. 1

eine Draufsicht auf eine erste Oberfläche eines Akustikelements gemäss einer Ausführungsform der Erfindung mit acht rechteckigen mikroperforierten Absorbern,

Fig. 2

eine Teilansicht auf eine erste Oberfläche eines Akustikelements gemäss einer weiteren Ausführungsform der Erfindung in einem Eckbereich mit kreisrunden mikroperforierten Absorbern,

Fig. 3a

eine perspektivische Teilansicht auf eine erste Oberfläche eines Eckbereichs eines Akustikelements gemäss einer weiteren Ausführungsform der Erfindung mit quadratischen mikroperforierten Absorbern,

Fig. 3b

eine Seitenansicht auf das Akustikelement gemäss Fig. 3a, bei dem der Absorber über dem Tragelement und die Ausnehmung strichliniert dargestellt ist,

Fig. 3c

einen Querschnitt durch ein Akustikelement gemäss Fig. 3a mit eingesetztem Absorber gemäss einer Ausführungsform der Erfindung in Sandwichbauweise,

Fig. 4

einen Querschnitt durch ein Akustikelement gemäss Fig. 3a mit eingesetzten Absorber gemäss einer weiteren Ausführungsform der Erfindung als Einfachelement,

Fig. 5a

eine perspektivische Teilansicht auf eine erste Oberfläche eines Eckbereichs eines Akustikelements gemäss einer weiteren Ausführungsform der Erfindung mit kreisrunden Ausnahmeöffnungen im Tragelement und überlagernd angeordneten quadratischen Absorbern mit Mikrospalten,

Fig. 5b

eine Seitenansicht auf das Akustikelement gemäss Fig. 5a, bei dem der Absorber über dem Tragelement gezeichnet und die Ausnehmung strichliniert angedeutet ist;

Fig. 5c

einen Querschnitt durch ein Akustikelement gemäss Fig. 5a mit eingesetztem Absorber gemäss einer Ausführungsform der Erfindung als Einfachelement,

Fig. 6a

eine Teilansicht auf einen Eckbereich einer ersten Oberfläche eines aus Stäbchen aufgebauten Absorbers mit Mikrospalten in einer erfindungsgemässen Ausführungsform ,

Fig. 6b

eine perspektivische Ansicht auf einen ersten Endbereich eines einzelnen Stäbchens eines Absorbers gemäss Fig. 6a, in einer nicht erfindungsgemässen Ausführungsform

Fig. 7

eine Teilansicht auf einen Eckbereich einer ersten Oberfläche eines aus Stäbchen aufgebauten Absorbers mit Mikrospalten gemäss einer weiteren nicht erfindungsgemässen Ausführungsform der Erfindung,

Fig. 8

eine Teilansicht auf einen Eckbereich einer ersten Oberfläche eines aus Stäbchen aufgebauten Absorbers mit Mikrospalten gemäss einer weiteren nicht erfindungsgemässen Ausführungsform der Erfindung,

Fig. 9a

ein Diagramm zur Absorptionsleistung eines schallabsorbierenden Akustikelements gemäss einer Ausführungsform der Erfindung mit zwei Absorptionsmaxima, und

Fig. 9b

ein Diagramm zur Absorptionsleistung eines schallabsorbierenden Akustikelements gemäss einer weiteren Ausführungsform der Erfindung mit einem breiten Absorptionsmaximum.

On the basis of figures, which represent only embodiments, the invention will be explained below. Show it

Fig. 1

8 a top view of a first surface of an acoustic element according to an embodiment of the invention with eight rectangular microperforated absorbers,

Fig. 2

3 a partial view onto a first surface of an acoustic element according to a further embodiment of the invention in a corner area with circular microperforated absorbers,

Fig. 3a

3 a perspective partial view of a first surface of a corner region of an acoustic element according to a further embodiment of the invention with square microperforated absorbers,

Fig. 3b

a side view of the acoustic element according to Fig. 3a in which the absorber is shown in dashed lines over the support element and the recess,

Fig. 3c

a cross section through an acoustic element according to Fig. 3a with inserted absorber according to an embodiment of the invention in sandwich construction,

Fig. 4

a cross section through an acoustic element according to Fig. 3a with absorbers used according to a further embodiment of the invention as a single element,

Fig. 5a

a partial perspective view of a first surface of a corner region of an acoustic element according to another embodiment of the invention with circular holes in the support element and superposed square absorbers with micro-gaps,

Fig. 5b

a side view of the acoustic element according to Fig. 5a in which the absorber is drawn over the support element and the recess is indicated by dashed lines;

Fig. 5c

a cross section through an acoustic element according to Fig. 5a with inserted absorber according to an embodiment of the invention as a single element,

Fig. 6a

1 is a partial view of a corner region of a first surface of a rod-shaped absorber with micro-gaps in an embodiment according to the invention,

Fig. 6b

a perspective view of a first end portion of a single rod of an absorber according to Fig. 6a in an embodiment not according to the invention

Fig. 7

1 is a partial view of a corner region of a first surface of a microsphere absorber constructed of rods according to a further embodiment of the invention not according to the invention;

Fig. 8

1 is a partial view of a corner region of a first surface of a microsphere absorber constructed of rods according to a further embodiment of the invention not according to the invention;

Fig. 9a

a diagram of the absorption performance of a sound-absorbing acoustic element according to an embodiment of the invention with two absorption maxima, and

Fig. 9b

a diagram of the absorption performance of a sound-absorbing acoustic element according to another embodiment of the invention with a broad absorption maximum.

In the FIG. 1 is a plan view of a first surface 7 of a rectangular acoustic element 1 according to an embodiment of the invention roughly sketched. Recesses for eight rectangular micro-perforated absorber 2 in a support element 2 are dimensioned so that the used Absober 3 occupy about 40% of the surface of the acoustic element. The arrangement of the absorber 3 within the carrier element 2 is essentially freely selectable, but for reasons of stability, it is advisable to provide a sufficiently wide web area to the edges of the support element 2 and between the individual absorbers 3.

In the FIG. 2 a corner region of an acoustic element 4 is shown according to a further embodiment of the invention, in which the absorber 6 are formed as a circular inserts.

On the construction of a first embodiment according to the invention acoustic elements will be described below with reference to the FIGS. 3a to 3c To be received. In the FIG. 3a is a partial perspective view of a first surface 11 of a corner region of an acoustic element 8 according to another embodiment of the invention shown in which square micro-perforated absorber 9 are inserted into corresponding receiving openings of a carrier glass pane 10. In the FIG. 3b is a side view of a portion of the acoustic element 8 according to Fig. 3a shown. An absorber 9 is detached from the support element 10 and shown in the carrier glass pane via a recess 12 indicated by dashed lines. The thickness d _{T of} the carrier glass pane 10 substantially corresponds to the thickness d _{A of} the square absorber element. From the in Figure 3c shown cross section of the carrier glass 10 with inserted absorber 9 is clear that the sandwich constructed absorber element 9 flush with the carrier glass 10 can be used. A first microperforated plate 13 terminates flush with the first surface 11 of the carrier glass 10 and the corresponding second microperforated plate 15 forms a flush fit to the rear surface 17 of the support plate 10. The rectangular in cross section absorber 9 are enclosed with four side walls 14, so that they can be easily used as compact cuboidal units in the correspondingly formed recesses 12 and glued 16 can be there.

The sandwich-like structure of in the FIG. 3 illustrated absorber element 9 with cavities 19 formed by webs 18 between two microperforated plates 13, 15 is substantially in the EP 07405185.5 described and need not be explained here. The two microperforated plates are interspersed with a plurality of acoustically effective microholes having a diameter of about 0.35 mm so that they have an acoustically effective open area of 7% with respect to the entire first surface 20 of the microperforated plate 13. In the carrier glass plate 10 according to the in FIG. 3 In the exemplary embodiment illustrated, the surface portion of the recesses 12 adds up to approximately 44% of the surface of the first surface of the carrier glass, so that the acoustically effective open area of the microperforation of the microperforated plate 13 in the absorbers 9 accounts for approximately 3.1% of the entire first surface 11, 20 of the acoustic element 8 makes. Since support glass plate 10 and absorber 9 are constructed symmetrically with respect to their first and second surfaces, the acoustic element with a thickness d _T of 12 mm and a dimension of 1.4 mx 1 m, for example, can be used as a room divider.

According to a preferred embodiment, the first 13 and the second microperforated plate 15 are provided with different microperforations, which have different absorption maxima in the sound absorption, as in the FIG. 9a , will be discussed in more detail below, is shown.

In the FIG. 4 is indicated that in the square recesses of the carrier glass plate 10 also suitable simple absorber 21 with only one microperforated plate 22 flush with the first surface 11 can be used. The support structure of the microperforated plate 22 consists for example of a pressboard plate 23, which is interrupted by a plurality of regularly arranged circular cylindrical cavities 23. Since the absorption element 21 has a microperforated plate 25 with a single type of uniform microholes, also has the corresponding absorption maximum of the absorber 21 only to a maximum, as in the FIG. 9b , will be discussed in more detail below, is shown.

In the FIG. 5a is a partial perspective view of a first surface 32 of a corner region of an acoustic element 25 according to a further embodiment of the invention with circular holes 28 in the support element 27 is shown. The absorbers 26 for insertion into the circular receiving openings have substantially square absorber plates 30 with a plurality of micro-columns 31 supported by a retaining ring 29. When inserting the absorber 26 in the support plate 27 is, as in the FIG. 5b shown, the retaining ring completely sunk in the recess of the carrier glass pane 27 until the absorber plate 30 rests on the first surface 32 of the carrier glass. The square absorber plate 30 with the plurality of micro-gaps 31 is in turn preferably stabilized by a support structure 33 with a plurality of cavities 34 lying in the absorber. The FIGS. 5b and in particular 5c show that the absorber plate 30 covers or overlays not only the recess 28 but also portions of the first surface 32 of the carrier glass 27 in peripheral regions. The proportions of the micro-slots, which come to lie directly on the carrier glass plate in these overlapping areas, although hardly have an acoustic absorption performance, given the enormously increased design possibilities However, such superimposed embodiments are still interesting. Although in the FIG. 5b In turn, an absorber glued into the receiving opening with the retaining ring 29 is shown, it is easy to understand that the absorbers can generally also be inserted into the receiving openings by means of clamping holders.

The structure of a micro-slotted absorber element according to a non-inventive embodiment is in the Fig. 6a outlined. In the partial view of a corner region of a first surface 35 it is shown how a corresponding number of micro-gaps 31 are formed between the rods 36 by a plurality of spaced-apart sticks 36. The rectangular cross-section rods 36 are, for example, 200 mm long and have a square cross-section of 20 × 20 mm in the end regions 38. In the middle region 37, a 0.2 mm deep groove is ground on one side, so that the micro-gaps 31 result with appropriate alignment of the rods by gluing the end regions 38. The end regions are only a few mm long, so that the illustrated absorber plate with a gap width of 0.2 mm has an acoustically effective open area of approximately 10% with respect to the first surface. The central areas can also be provided with two or more grooves, so that the 1.8 mm wide webs 37 form two or more micro-gaps and are supported between these two or more times.

In the FIGS. 7 and 8 Further non-inventive embodiments of absorbers are shown with microcolumns in which rectangular in cross-section bars 39 with a height of 2.0 mm and a width of 1.8 mm to absorber plates with an area of 200 x 200 mm, 0.2 mm wide micro gaps 31 and an acoustically effective open area of about 10%.

In the absorber element according to the FIG. 7 are the rods 39 at the end regions with a special adhesive 42 containing spherical spacers of 0.2 mm diameter, glued together to form a plate-shaped absorber element. The spacer elements ensure that the sticks 39 can not approach more than the desired micro gap width of 0.2 mm during bonding. The narrow tolerance ranges with which the spacer elements can be produced, ensure that the gap widths also vary only within a narrow range and the absorption capacity of the absorber plates can be set precisely defined. The spacers are preferably made from materials that neither swell in the adhesive, nor show shrinkage during curing or drying of the adhesive.

In the absorber plate 41, as in the FIG. 8 is drawn, the rods 39, which do not differ in dimensioning from those of the previous example, inserted with their end portions in a comb 44 having a plurality of teeth 45 with a width of 0.2 mm, and thus the width of the to be created Micro gaps 31 pretends. The rods 39 can be glued or clamped directly into the comb 44. In this way, 100 sticks are combined to form an absorber plate, this again has an area of 200 x 200 mm and 99 micro gaps with a width of 0.2 mm, resulting in an acoustically effective area of approximately 10% relative to the first surface of the Add absorber plate.

The mass, which are given in the embodiments of the absorber plates with micro-columns, to allow the comparison of these plates and do not give the impression that can be produced by means of the methods described only plates with the specified masses. On the contrary, the production methods described allow the person skilled in the art a great deal of freedom in the dimensioning and adjustment of the absorber power of the absorber plates. It will be understood that the plates can be used alone in single as well as in twos or in several composite sandwich elements. In non-inventive embodiments, these absorber plates are constructed from glass rods and replace the procedurally complex process for micro-slots or microperforating glass plates. In order to additionally stabilize the absorber plates with the preferably clarified glass rods, for example, the rods are stabilized and secured at the end regions on the front side or circumferentially with frame elements.

In order to achieve high open areas and thus good sound absorption values over wide frequency ranges despite narrow microcolumns, very narrow gaps with widths in the range of 0.05 to 0.3 mm, preferably 0.2 mm, have proven to be advantageous. The narrow column widths of less than 0.3 mm can be achieved according to further advantageous embodiments of the invention by additive methods, such as the offset superimposition of two inserts with gap widths of more than 0.3 mm.

If absorbers with broader gaps are constructed according to the method according to the invention, then the column width can be reduced in subsequent process steps, for example by immersion in clearcoat.

In the diagram of FIG. 9a is that the absorption power alpha (y-axis) is plotted against the frequency (x-axis) in the range of 62.5 to 4000 Hz. The very broad absorption spectrum of an absorber sandwiched from two absorber plates with microcolumns has two absorption maxima. The columns of the first absorber plate with a thickness of 1 mm are 0.2 mm wide and have a resonance length (as a Helmholtz resonator) of 12 mm. They form an acoustically effective open area of 10% in the absorber plate. The columns of the second, 5 mm thick absorber plate are also 0.2 mm wide, have a resonance length of 45 mm and form in the second absorber plate an acoustically effective open area of 10%. The bars are each 1.8 mm wide. The two absorption maxima are at about 1000 and 3500 Hz.

In the FIG. 9b For comparison, an absorption spectrum of a simply constructed absorber with a 5 mm thick absorber plate with 1.8 mm wide bars and 0.2 mm wide micro gaps with a resonance length of 40 mm, that is, the distance from the reverberant rear wall is 40 mm. The measured acoustic element has an acoustically effective open area of 5% and absorbs with a broad absorption spectrum whose maximum lies in the region of about 800 Hz at 1.

In view of the above-disclosed technical teaching of the present invention, it will be apparent to those skilled in the art that there are enormous variations in material selection and structural variations, and particularly in the nature of the absorber.

The inventive absorption elements leave the manufacturer a maximum of creative freedom. Both the type of absorber, as well as their arrangement, as well as the shape and design of the absorber inserts can be varied within wide ranges.

According to further embodiments, which are not illustrated in the figures, the transparent and / or translucent absorbers are combined with lighting means in order to produce lighting effects in addition to the sound absorption. Glass absorber inserts are ideally suited to set lighting accents in the acoustic element in combination with LEDs, light guides or other light sources. The bulbs can be mounted such that they do not adversely affect the absorber performance.

List of reference numbers

1

acoustic element

2

supporting member

3

absorber

4

acoustic element

5

supporting member

6

absorber

7

first surface

8th

acoustic element

9

absorber

10

Carrier glass

11

first surface

12

recess

13

Microperforated plate

14

Side wall

15

Microperforated plate

16

bonding

17

second surface

18

web

19

cavity

20

first surface

21

absorber

22

microperforated plate

23

plate

24

cavity

25

acoustic element

26

absorber

27

support plate

28

recess

29

retaining ring

30

absorber plate

31

microcracks

32

first surface

33

support structure

34

cavity

35

first surface

36

rod

37

the central region

38

end

39

rod

40

absorber plate

41

absorber plate

42

adhesive

43

Distance particles

44

Comb

45

teeth

Claims (12)

1. Acoustic elements (1, 4, 8, 25) comprising at least one support element (2, 5) and at least one sound-absorbent absorber (3, 6, 9, 21, 26), the support element (2) being provided with at least one cutout (12, 28) for receiving at least one sound-absorbent absorber (3, 6, 9, 21, 26), characterized in that the area of the at least one cutout (12, 28) makes up 20 to 50% of the surface of the support elements (2, 5), and in that the at least one absorber consists of glass material and has microslots produced using a wire saw method.
2. Acoustic elements according to Claim 1, characterized in that the at least one absorber has an acoustically effective open area which is formed by microperforation, microslots, microgaps or a combination thereof and which corresponds to 1 to 12%, preferably 7 to 12%, with particular preference 10% of the total area of a first surface of the absorber.
3. Acoustic elements according to Claim 1 or 2, characterized in that the at least one absorber is manufactured from glass materials and/or non-vitreous materials such as metal, plastic and/or wood.
4. Acoustic elements according to one of Claims 2 to 3, characterized in that webs with a width of 1 to 8 mm, preferably 1.5 to 3 mm, and with particular preference 1.8 mm are arranged between the microslots.
5. Acoustic elements according to Claim 1, characterized in that the at least one absorber comprises sound-absorbing membranes, foils, woven and nonwoven textiles, open-pore foams or expanded building materials and/or combinations thereof.
6. Acoustic elements according to Claim 1, characterized in that the acoustically active absorber materials make up between 3 to 60%, preferably between 5 to 20% of the total area of a first surface of the acoustic element, and have a specific flow resistance of between 500 to 3000 Pa*s/m.
7. Acoustic elements according to one of Claims 1 to 5, characterized in that the support element is manufactured from glass or synthetic glass, preferably from flat glass, float glass, mirror glass, laminated safety glass, single-pane safety glass or special glass.
8. Acoustic elements according to one of Claims 1 to 6, characterized in that the at least one absorber is designed as a simple element or as a sandwich construction with or without nonwoven material.
9. Acoustic element according to one of Claims 1 to 7, characterized in that the at least one absorber is adhesively bonded in the respective receiving opening or is held fixedly or releasably by means of a holding device.
10. Method for producing acoustic elements (1, 4, 8, 25) in accordance with one of Claims 1 to 9, characterized in that microslots are sawn by using a slurry wire saw method in absorber plates of glass.
11. Method for producing acoustic elements (1, 4, 8, 25) in accordance with Claim 10, characterized in that the microslots have a slot width of 0.1 to 0.3 mm.
12. Method for producing acoustic elements (1, 4, 8, 25) in accordance with either of Claims 10 and 11, characterized in that a support element of glass is provided with receiving openings, the inner walls of the receiving openings are rendered capable of being secured, and the support element (2, 5) is subsequently secured and provided with the at least one absorber (3, 6, 9, 21, 26).

Images