DE102005012166A1 - Sound absorber, has surface unit with surface layer having micro-channel openings in area of other channel openings, where width of one of the openings is smaller than width of other openings - Google Patents

Abstract

The absorber has a surface unit (11) with a plastic foil (18) and a surface layer (22), and a number of micro channel openings (12) that are present in the unit. One of channel openings (20) is present in the foil, where the surface layer is introduced into the foil. The surface layer has other channel openings (26) in an area (24) of the channel openings (20). Width of the openings (26) is smaller than the width of the openings (20). An independent claim is also included for a method of manufacturing a sound absorber.

Description

The The invention relates to a sound absorber having a surface element, in which a plurality of micro-passage openings are present. object The present invention further provides a method of manufacturing such a sound absorber.

A sound absorber of the type mentioned is from the DE 197 54 107 C1 known. This consists of microperforated, so provided with holes films or thin plates, with multiple films or plates can be provided in any arrangement to each other. In addition to these sound absorbers, those with large slot-shaped recesses are known, which are used for example in gymnasiums. With the known sound absorbers, the acoustic properties of a room can be selectively changed by sound waves are converted into heat.

task The present invention is a sound absorber of the above so-called type so that its sound-absorbing Properties as possible good at simpler and cheaper Production are.

These Task is in a sound absorber of the type mentioned solved by that the surface element a film has been introduced into the first passage openings are, and a surface layer which is applied to the film and in the range at least a first passage opening has a second passage opening, whose width is smaller than the width of the first passage opening.

• a. Einbringen der ersten Durchgangsöffnungen in die Folie;
• b. Aufbringen der Oberflächenschicht;
• c. Einbringen der zweiten Durchgangsöffnungen in die Oberflächenschicht im Bereich der ersten Durchgangsöffnungen.

In a method of the type mentioned, the object is achieved in that it comprises the following steps:

• a. Inserting the first passage openings in the film;
• b. Applying the surface layer;
• c. Introducing the second passage openings into the surface layer in the region of the first passage openings.

Advantages of invention

According to the invention was found that the sound-absorbing properties at a very thin surface element such as a foil then are best when the width the micro-passages is very low. Micro-through holes with very low To make width for example by drilling or piercing, is very difficult, since it was found that the manufactured Micro through-opening closes again after pulling out the tool.

at The present invention therefore takes a completely different approach: in the film itself, first through holes are present, which are so sufficient far, that they are using normal manufacturing methods, for example by piercing, drilling, punching or by laser can be produced. The for the However, sound-absorbing characteristics relevant second through hole is produced with the aid of the surface layer, which is applied to the film and the one much lower Thickness than the film has. usual Thicknesses of the surface layer are in the range of one tenth to one hundredth of the thickness the foil.

According to the invention was now found that micro-passages, in such a surface layer in the area of the first passage openings are made, even after the manufacturing process not again close, but a desired one Maintain width. The foil ultimately serves only as Carrier, the for the sound absorbing properties of essential micro-passages are mainly due to the second through holes in the surface layer educated. It is understood that as a foil all thin surface elements can be used for example, thin Sheets, thin plastic plates or transparencies in the true sense.

at an advantageous development of the sound absorber according to the invention causes the arrangement of the first through holes an optical effect, especially since the coating can be made transparent. The first Through openings So in this case, they have a double function, for one thing the basis for the second through holes form, but at the same time for the visual design of the sound absorber serve.

there can the first passages be arranged in a particular pattern and / or they can only be present in at least a portion of the film.

Since the first passage openings have a comparatively large width, their shape can be specified very well, for example as circular and / or slot-shaped passage openings. As a result, on the one hand, desired optical effects can be achieved, but on the other hand, it has also been found that the sound-absorbing properties are also tailored to the special requirements of the individual case due to the shape of the first passage openings you can.

The first passages preferably have a width of about 0.1 mm to about 5.0 mm. A special visual effect can be achieved when the film translucent is. This is especially true for a sound absorber that can be arranged in front of a window or which as a jacket of a filament serves.

If the surface layer transparent, preferably crystal clear, come the optical effects the film, for example, through the first through holes be particularly effective. A possibility, such a surface layer For example, it is a PTFE material includes.

advantageously, the sound absorber is designed so that the area of the surface layer, in which the second passage opening is present, the first passage opening substantially spans. "Essentially" means in this Case, that the surface layer does not or at least not substantially penetrates into the first passage opening. Such a sound absorber is relatively simple and inexpensive produced.

alternative For this purpose, the area of the surface layer in which the second Through opening available is the first through hole also essentially complete. This embodiment is more stable overall.

A Further development of the method according to the invention provides that in step c, the composite of film and surface layer is stretched or deformed such that the surface layer tears in the region of at least one first passage opening, whereby at the tearing point a second passage openings arises. This is a concrete way, second passages produce with a minimum width, as with mechanical measures is not feasible.

alternative for this it is possible that in step c on one side of the composite of foil and surface layer such a higher one Pressure prevails as on the other side of the composite that thereby the surface layer tears in the region of at least one first passage opening, whereby at the tearing point a second passage opening arises. This is technically easy to implement and enables the Introduction of the second through holes even in a continuous Method.

A Another development of the method according to the invention provides that the film is plastically stretched or deformed in step c. hereby becomes the width of the first passages, first of spans the surface layer or at least partially completed become permanently enlarged. By an appropriate choice of material for the surface layer, for example, by using a material with a corresponding one modulus of elasticity or a corresponding brittleness, So can a desired "crack width" and thus a desired dimensioning the second through holes in the surface layer be achieved.

alternative for this it is possible that the surface layer before step c in the area of the first through holes is under tension and that the film elastically stretched or deformed in step c becomes. The bias of the surface layer in Area of the first passages For example, by an appropriate choice of material during the Drying of the surface layer caused become. In this variant of the method according to the invention remain original Dimensions of the film obtained.

proposed further, it is preferable that a portion of the surface layer be due to the there prevailing surface tension in or after the step c at least partially around the edge the first through hole sets, creating a second passage opening with a smaller width arises as the width of the first passage opening.

drawings

following become particularly preferred embodiments the present invention with reference to the accompanying Drawing closer explained. In the drawing show:

1 a perspective view of a sound absorber;

2 an enlarged plan view of a portion of the sound absorber of 1 ;

3 a section through an area of the sound absorber of 1 in an intermediate state during production;

4 a section through an area of the sound absorber of 1 in the final state;

5 a section through an area of an alternative embodiment of a sound absorber in an intermediate state during manufacture;

6 a section through an area of the sound absorber of 5 in the final state;

7 a sectional view similar 3 a further embodiment after a first intermediate step; and

8th a sectional view of the embodiment of 7 in the final state.

description the embodiments

A sound absorber carries in 1 Overall, the reference number 10 , In the present case, it is designed as a rectangular element, in which a multiplicity of micro through-openings 12 available. In order to achieve the desired sound-absorbing properties, the sound absorber 10 at a small distance from a reverberant wall 14 arranged. Alternatively, it could also be arranged freely as a room divider in a room. How out 2 shows, in the embodiment shown there, the micro-passage openings 12 over the surface of the sound absorber 10 in a regular pattern at approximately equal distances from a micro-through hole 12 arranged to the other. Conceivable, however, are any other and irregular patterns. How out 1 indicates, has a border area 16 of the sound absorber 10 no micro-passage openings 12 on. This creates on the one hand a special optical effect and on the other hand allows the attachment of fasteners (in 1 not shown) on which the sound absorber 10 for example, can be hung.

The sound absorber 10 is prepared as follows (see 3 and 4 ): In a translucent in the present embodiment plastic film 18 are first circular first through holes 20 introduced, the width W in the present embodiment is 0.5 mm. On the plastic film 18 then becomes a thin surface layer 22 applied from a crystal-clear PTFE material in the present embodiment. In an embodiment not shown, another, for example, a light impermeable and / or a colored material or a different base material may be used as PTFE. In principle, many types of drying liquids are suitable.

The application is made so that the first through holes 20 of the material of the surface layer 22 not filled, but spanned. This condition is in 3 shown. The material of the surface layer 22 is chosen so that after the application of the surface layer 22 on the plastic film 18 those areas 24 that the first passages 20 span, under a bias.

The material of the surface layer 22 is much brittle than the material of the plastic film 18 , In a further process step, the plastic film 18 stretched elastically. This breaks the surface layer 22 in the fields of 24 that the first passages 20 span, creating second through holes 26 in the surface layer 22 in these areas 24 arise. The resulting second passage openings 26 have a smaller width w than the first through holes 20 ,

Instead of elastic stretching of the plastic film 18 For example, it may also be bent, with the center of curvature bending on that of the surface layer 22 opposite side of the plastic film 18 lies. This can also cause the cracking of the surface layer 22 in that area 24 be effected. Also a plastic stretching of the plastic film 18 is possible. Furthermore, the surface layer 22 Also be pneumatically pressurized by constantly or cyclically on both sides of the composite of plastic film 18 and surface layer 22 a different pressure is set. If the pressure difference is sufficiently large, the surface layer ruptures 22 in the fields of 24 , Finally, it is also conceivable that the second passage openings 26 in the fields of 24 in the surface layer 22 be punched.

The result is a sound absorber 10 with a surface element 11 which is made of the film 18 and the surface layer 22 consists. The micro-passage openings 12 are ultimately through the second through holes 26 in the surface layer 22 educated. The in the slide 18 existing first passages 20 serve as optical design means and as "placeholders" for the production of the micro-passage openings 12 ,

A variant of a sound absorber 10 is in the 5 and 6 shown. In this case, here and below, such elements and regions bear, which equivalent functions to elements and areas of a sound absorber described above 10 have the same reference numerals. In the in the 5 and 6 shown sound absorber 10 penetrates the surface layer 22 when applied to the plastic film 18 also in the first passages 20 a (compare 5 ). Again, by a corresponding elongation or deformation of the plastic film 18 a crack of the surface layer 22 in the fields of 24 for generating second passage openings 26 lead, whose width w is significantly smaller than the width W of the first through holes 20 ,

By using a crystal-clear PTFE material for the surface layer 22 this is for the user of the sound absorber 10 not visible. The visual impression is therefore mainly through the plastic film 18 and in this existing first through holes 20 causes.

Another embodiment is in the 7 and 8th shown: After that the surface layer becomes 22 only one-sided on the plastic film 18 applied, in such a way that it has a first passage opening 20 with an area 24 spans. Now the surface layer becomes 22 in the area 24 torn to break. The material of the surface layer 22 or the nature of their application is chosen so that the area 24 because of the prevailing surface tension in the manner of a collar 22a or a lining in a precisely adjustable degree, for example by an appropriate choice of material or the choice of a specific processing temperature, around the edge of the first through hole 20 sets. In this way, in the first through hole 20 a second passage opening 26 formed, the acoustically effective width w is smaller than the width W of the first passage opening 20 ,

The just mentioned Manufacturing principle can also be applied to a double-sided coating be exploited by the shrinkage of the surface layer while drying a lining of the first through hole to achieve.

Claims (18)

Sound absorber ( 10 ) with a surface element ( 11 ) in which a plurality of micro-passage openings ( 12 ), characterized in that the surface element ( 11 ) a film ( 18 ), in the first passage openings ( 20 ) and a surface layer ( 22 ) applied to the film ( 18 ) is applied and in the area ( 24 ) at least one first passage opening ( 20 ) a second passage opening ( 26 ) whose width (w) is smaller than the width (W) of the first passage opening ( 20 ). Sound absorber ( 10 ) according to claim 1, characterized in that the first passage openings ( 20 ) are arranged and formed so as to cause an optical effect. Sound absorber ( 10 ) according to claim 2, characterized in that the first passage openings ( 20 ) are arranged in a specific pattern. Sound absorber ( 10 ) according to one of claims 2 or 3, characterized in that the first passage openings ( 20 ) only in at least one area ( 15 ) of the film ( 18 ) available. Sound absorber ( 10 ) according to one of the preceding claims, characterized in that at least some of the first passage openings ( 20 ) are circular and / or slit-shaped and / or irregular. Sound absorber ( 10 ) according to one of the preceding claims, characterized in that the first passage openings ( 20 ) have a width (W) of about 0.1 mm to about 5.0 mm. Sound absorber ( 10 ) according to one of the preceding claims, characterized in that the film ( 18 ) is translucent. Sound absorber according to one of claims 1 to 6, characterized in that the film is impermeable to light. Sound absorber ( 10 ) according to one of the preceding claims, characterized in that the surface layer ( 22 ) is transparent, preferably crystal clear. Sound absorber ( 10 ) according to claim 9, characterized in that the surface layer ( 22 ) comprises a PTFE material. Sound absorber ( 10 ) according to one of the preceding claims, characterized in that the area ( 24 ) of the surface layer ( 22 ), in which the second passage opening ( 26 ), the first passage opening ( 20 ) is substantially spanned. Sound absorber ( 10 ) according to one of claims 1 to 10, characterized in that the area ( 24 ) of the surface layer ( 22 ), in which the second passage opening ( 26 ), the first passage opening ( 20 ) at least partially. Method for producing a sound absorber ( 10 ) according to one of the preceding claims, characterized in that it comprises the following steps: a. Introduction of the first passage openings ( 20 ) in the film ( 18 ); b. Application of the surface layer ( 22 ) on the film ( 18 ); c. Inserting the second passage openings ( 26 ) in the surface layer ( 22 ) in the region of the first passage openings ( 20 ). A method according to claim 13, characterized ge indicates that in step c the composite of film ( 18 ) and surface layer ( 20 ) is stretched or deformed such that the surface layer ( 22 ) in the area ( 24 ) at least one first passage opening ( 20 ), whereby at the tear point a second passage opening ( 26 ) arises. A method according to claim 13, characterized in that in step c on one side of the composite of film ( 18 ) and surface layer ( 20 ) such a higher pressure prevails than on the other side of the composite, that thereby the surface layer ( 22 ) in the area ( 24 ) at least one first passage opening ( 20 ), whereby at the tear point a second passage opening ( 26 ) arises. Method according to claim 13, characterized in that the film ( 18 ) is elastically and / or plastically stretched or deformed in step c. Method according to one of claims 13 to 16, characterized in that the surface layer ( 22 ) before step c in the area ( 24 ) of the first passage opening ( 20 ) is under tension, and that the surface layer in step c during the drying or curing by tearing stresses. Method according to one of claims 13 to 17, characterized in that an area ( 24 ) of the surface layer ( 22 ) preferably due to the surface tension prevailing there in or after the step c at least partially around the edge of the first passage opening ( 20 ), whereby a second passage opening ( 26 ) with a smaller width (w) than the width (W) of the first passage opening ( 22 ).