DE8201599U1 - MUFFLER BACKGROUND - Google Patents

Description

- 4 -
description

The invention relates to a silencer backdrop for flowing gases * in particular for ventilation »- and air conditioning systems, with an approximately to be arranged parallel to the direction of flow, plate-shaped " multi-part Kuliasenk body, which has an absorbent core made of porous, material suitable for soundproofing, such as mineral wool, furthermore one facing the absorption core on its side facing the gas flow protective film covering the th side, especially made of plastic, and a mechanically strong, perforated, outer cover covering the protective film on its side facing the gas flow, like a perforated plate or a wire mesh, with a minimum percentage of holes of about 15%, preferably of about 30%, and in which a mat-like, peel-permeable intermediate layer is arranged between the protective film and the outer cover | is.

Such scenes are, for example, in supply and exhaust air ducts of ventilation and air conditioning systems used in such a way that a » On the one hand, the best possible sound attenuation is achieved and, on the other hand, since the flow resistance of the gas flowing through it is also grease be kept low. Muffler backdrops with an absorbent core covering protective film are mainly used for pure IU (UBM, for example, of sick people and elderly people, operating stations, Computer manufacturing plants and the like. the Protective film ensures, on the one hand, that there is a seal against the outside of the absorption core »whereby a gas flow of Absorption core or mineral wool particles is prevented, and on the other hand for an inwardly directed fire resistance

Il Il

I · I ItI • · III Il »· · ·

tung de · absorption core »so that in this koine bacterial nests can train. Such a protective film is mandatory in various cases of application. This must be very be thin / so that sufficient sound transparency is maintained for the sound penetrating from the outside into the absorption core. On the other hand, the protective film must not be in contact with the outer cover / since this reduces the sound attenuation of the Ku- " lisse would occur.

With known silencer scenes of the type described an intermediate layer consisting of glass fleece is located between the protective film and the outer cover / the largely is sound permeable and for the necessary distance between the thin protective film and the outer cover. However, it has been shown / that such a glass fleece intermediate layer basic disadvantages ha? »,. Because of the relatively large proportion of minimum holes the outer cover, it is inevitable that by the Gas flow particles of the glass fleece are separated and entrained. Apart from that / that this leads to a certain amount of pollution 'of the Gaaetrome occurs / is further suspected / that these particles have a carcinogenic or carcinogenic effect.

The present invention is therefore based on the object Silencer backdrop of the type mentioned while at least largely maintaining their acoustic properties with simple as well as inexpensive means to train dad the related ■ effectively avoided the disadvantages outlined with the intermediate layer wardan.

to enjoy the task at hand

# »I ■

> ι ι, * \ j

», Ι ,, Jr

»I I I t. ρ · I I 1 I) I t

* t I ι ι ι ι> »

(«Ti ti · I I <Il> ..

fer-backdrop of the type mentioned in the generic term according to the invention thereby also that the intermediate layer is a thin-layer spacer made of thin plastic threads, their mutual Clearances to prevent contact »wipe the protective film and the outer cover sufficient klwin and / for good sound permeability of the intermediate layer are as large as possible, the distances being smaller, the thinner the plastic threads and the more flexible or thinner the

»Protective film are. Such plastic threads have the essential

^The advantage of this is that, unlike the non-woven fibers of a glass fleece intermediate layer, they are not subjected to any abrasion caused by gas flow or other harmful abrasions. In principle, the threads of the intermediate layer could also consist of metal. On the other hand, Kunststsf £ -FSde »each have the essential advantage that they provide more effective protection for the protective film. In addition, if the thickness of the plastic threads is sufficiently small and there is sufficient thread spacing, they guarantee perfect visual transparency of the outer gate parts. It has been found, 0 ^d * ^{ß DJL} · "wipe the Schutefolie and the outer cover arranged plastic filaments have no significant adverse effect on the damping behavior of the link. Such a spacer, which can be designed differently in terms of its detailed design and, for example, strip-like or mesh-like, can be manufactured very inexpensively and installed extremely easily in the backdrop. It is also easily possible to subsequently replace the built-in glass fleece intermediate layer with an intermediate lifting device of the type according to the invention when the sound absorber baffles are already in place.

• · B «I

b · · · I i

■ · · Il

■ · t W 4

»■ act« i

• «« ιΐ · a · ■ a t «ι« ,; ^

In a further embodiment, strand-like plastic threads consisting of individual fibers can be used for the intermediate layer. This Hafinahme can ensure a sufficient sound transparency in the immediate area yarn may be expedient to ψ in certain applications with relatively thick plastic threads and / or thread with relatively small intervals. * In general, however, thin 'solid' plastic threads should be sufficient4.

For the individual threads of the intermediate layer, different Plastics are used. Polyester »polyethylene, polyvinyl chloride and polyamide are particularly suitable for this. Zm With regard to the thin protective film that will not be damaged », The plastic threads must not have any sharp edges or surfaces that are too rough, rather their surfaces should be because of the constant contact with the protective film and certain relative movements between these parts rounded as possible and be limber. Regarding the tensile strength of the plastic thread there are no special function-related requirements to be made, unless the threads would, for example, on the Kulisson frame or clamped on the outer cover under tension.

In a particularly preferred embodiment, they become grid-like crossing plastic threads are used. Zn further development these can be woven or interwoven. Instead, the intersecting and mutually touching Kunststoi £ threads in adjacent levels of the intermediate layer get lost. In the latter case, in particular, it is advantageous / the plastic threads at the crossing points with

■ * mam *

to stick to each other, as if by heat pressure to each other weld. Such a grid-like or mesh-like spacer has the advantage that an attached, transportable and an easy-to-use mat made of plastic threads is present, the thread spacings are fixed. With a spacer, these advantages would only be parallel to one another running and held together at the end or otherwise fixed plastic threads are not readily given be, although in principle also such an embodiment variant is applicable. Overall, the plastic threads have a lattice structure with regard to production and handling and a reliable prevention of physical contact between the protective film and the outer cover as a special j

expedient.

The intermediate layer made up of a single plastic thread preferably has a thickness of about 0.1 to 1 mm and in the individual case of preferably about 0.25 mm. The thickness should be possible be small so that optimal sound transparency is maintained in the immediate area of the thread, but also with regard to manufacturability as well as the ability to Eä & dhäb a certain minimum not fall below. Otherwise the required thread-child spacing would also be too small, which would affect the manufacturing process of the spacer made more difficult and expensive.

In an expedient practical embodiment, in particular in conjunction with an interlayer thickness of about 0.25 mm, a thread spacing of about 3 to 10 mm, such as from j about 3.5 mm, proven to be sufficient. Far or an awl- | is sufficient

«Chen the thread center sat thread spacing of about 4 mm. These «preferred examples show that the individual plastic films existing spacers acoustically largely 'open * can be formed in order to achieve an optimal backdrop in terms of sound absorption.

In a further embodiment, plastic threads with at least ι partially flattened, such as oval. Cross-section can be used. In this way can be at about the same tenacity dünj) nere and thus achieve favorable acoustic interlayers what ι particularly in intersecting plastic threads advanta- \ way is. In this context it has to see at a practical \ Ausführungeform as assigned idle been found that the flattened plastic strands a measured transversely to the intermediate layer minimal Dickev fcße * | & tf s 0.15 mm and in the plane of Zwlschsn-. | layer measured maximum thickness of about 0.7 mm. However, this \ is, as with the other dimensions _w

only useful values in practical use, which can be adapted to the respective application.

Practical tests have shown that the individual plastic threads existing intermediate layer in an excellent way for use in conjunction with a plastic protective film is suitable, which has a thickness of only about 25 to 30 μ. Smaller thicknesses are likely, among other things, with regard to the vulnerability and the protective effect of the protective film are hardly used. Basically, however, is the interlayer spacer according to the present invention also for an application

- 10 »suitable with thinner or thicker protective foils.

A particularly flexible and versatile design of the Schaildässpzer Kulisee is characterized by a single or multi-layer absorption core made of porous material, such as mineral wool, with the same or different rough weight in layers, with a protective plastic film covering the absorption core on both sides, with an intermediate layer on both sides , and by an outer cover on both sides. Such Kulis-) to flow around both sides and arranged parallel to each other in many cases under a mutual spacing in the gas stream. Because of their double-sided use, such known scenes have a particularly good level of efficiency with regard to the sound-absorbing material utilization.

The invention is illustrated below on the basis of the drawing

leadership games explained in more detail. Ee show:

Figure 1 - a cutaway in a perspective view

SchalldXmpfer-Kulisee with double-sided and single ^J NEN plastic threads existing spacing; ernd * r

Intermediate layer according to the present invention,

Figure 2 - in an enlarged / cut out detail view an area of a first embodiment of the intermediate layer,

FIG. 3 - in an enlarged, cut-out detailed view a portion of a second embodiment of the Intermediate layer and

Figure 4 - a cut-out Teilquersohnltt, from which the spacing function of the intermediate layer according to the first Äusführur.gsfcra can be seen.

Il I I I I

In the embodiment shown in FIG. 1, it is a double-sided acting silencer backdrop, the absorption core is made up of several layers. It consists of a thicker core layer 10 and a thinner cover layer 12 covering these on both sides. These layers can consist of a suitable sound-absorbing material Material such as mineral wool or glass fleece / consist.

In a practical example in which the volume weight of the absorbent core increases from the inside out, the ■ Core layer 10 has a density of, for example, about 30 kp / m *, while the thinner cover layers 12 ″ in volume weight of two | for example 70 kp / m *.

In the present exemplary embodiment, both cover layers are 1

12 on the outside of a thin plastic cover 14 over I

covers, the thickness of which is about 30 μ. This protective film 14 is used

on the one hand to prevent abrasion of the absorbent core and _; .

on the other hand to prevent moisture from entering \

the absorption core so that there are no bacterial nests in it

^{v can} form |

i On the outer sides of the silencer facing the gas flow ^;

This setting is in the exemplary embodiment on both sides of jj

a fixed perforated plate 18 covered / their minimum perforation j £ t * ra is 30%. Between each plastic protective film 14 and each perforated plate 18 is a single plastic thread existing, thin, sound-permeable *, spacers Intermediate layer 16.

The muffler backdrop can have a backdrop frame 20, which in the present case consists of the »two-part absorption core

I I I I

ItII

ι ι ι ι

III «II I

- 12 -

holds. In the exemplary embodiment, the plastic protective films are used 14, the intermediate layers 16 and the perforated plates 18 «#N the outside of the backdrop frame a 20 attached. The type, iat is only an example and can be adapted to the respective requirements.

According to the exemplary embodiment from FIG. 2, the intermediate layer 16-1 corresponding to the intermediate layer 16 from FIG. 1 consists of plastic threads 22 and 24 crossing in a grid-like manner, which, as shown in FIG. 4, touch each other and run in different planes of the intermediate layer. The plastic threads 22 and 24 can be glued to one another at the Kreuaungostollen, as if blurred with one another by heat pressure. According to the illustration, the plastic threads 22 have a mutual spacing a, while the plastic threads 'A4 ' have a mutual spacing b. These distances a, b are - also in all other implementation examples - taking into account the thickness of the plastic threads or the intermediate layer as well as the properties of the plastic protective film 14 to always dig ao that the latter is not »it the outer cover or the Perforated plate 18 can come into contact. On the other hand, the distances a and b should be chosen to be possibly large with regard to an optimal sound permeability of the intermediate layer, while the thickness of the plastic threads should be small, among other things for the same reason.

The intermediate layer 16-1 from FIG. 2 can either be present in the form of a coherent dimension and be inserted, especially practical iat »or aie can also be achieved by suitable application as well as setting the Kunatatoff threads 22 on the one hand and

• · I

• · I

• · ι

- 13 -

the plastic threads 24 on the other hand on the gate frame 20 or the like are formed. The plastic threads 22, 24, each running in one plane, can each end at one end be connected to each other in order to facilitate handling and installation and to achieve the desired mutual thread alphabet su ensure.

In the exemplary embodiment from FIG. 3, the intermediate layer 16-2 corresponding to the intermediate layer 16 from FIG The designs nagora> ub glmif 3 V ° w | it also those from FIG. 2 certainly have advantages insofar as the plastic threads 26, 2B already have no mutual gluing in the thread composite The intermediate layer 16-2 is supported in the embodiment example from FIG FIG. 3 on these parts with a uniform distribution in points or areas.

FIG. 4 shows an example of how the intermediate layer 16-1 from FIG Plastic threads 22 and 24 extending across planes are able to keep them from the perforated plate 16. The same applies of course also for the intermediate layer 16-2 from FIG. 3.

The mutual thread spacings a and b are grid-like

• rl ■

- 14 -

intersecting plastic β toff "threads can be different or the same can be chosen large, the latter case being preferred. The intermediate layer 16 can instead of intersecting Plastic threads 22, 24 and 26, 28 also only consist of mutual Distance a or b plastic threads 22 or 26 or 24 or 26 running approximately parallel to one another exist. aside from that lattice structures can be used, their plastic threads do not cross at right angles, but diagonally. With accordingly These can also be similar to thin plastic threads be intertwined in a knitted fabric. These and other design variants are intended to be taken from the present invention.

§ training must be included, which also applies to the special structure the silencer backdrop applies, the absorption core of which is single-layer his or can have further additional components and which, in the case of only one-sided gas flow in the direction of arrow A or B, is to be designed to act only on one side. In In this case, the absorption core would only be on one side with a plastic protective film 14, an intermediate layer 16 and a layer

j ¹ J perforated plate 18 or the like to cover. The cross-section of the plastic threads is also not tied to the exemplary embodiments shown. It can for example and at least in part be flattened, such as oval. This applies above all to the mutual crossing areas in order to obtain the lowest possible thickness of the entire intermediate layer 16. Outside the intersection areas, the plastic threads can, in contrast to the illustration in FIG. 4, run somewhat indented. Such a structure arises, for example, when the intersecting plastic threads in the intersection areas

β · ♦ «

• ft · a

- 15 - f

are glued together by mutual «heat compression. i

In a practically tested embodiment with a plastic protective film of about 30 μ, an about 0.23 thick intermediate layer 16 was used * whose intersecting, woven plastic threads consisted of polyester and were firmly connected to one another by heat compression. At least in the mutual crossing area, the plastic threads had a minimum thickness of about 0.15 mm, measured at right angles to the intermediate layer, and a maximum thickness of about 0.7 × m, measured in the plane of the intermediate layer. The spaces between the plastic threads were roughly square and had a clear width of about 3.5 mm, while the thread length measured from thread center to thread center; distance was about 4 mm. A silencer backdrop equipped with such an intermediate layer exhibited an excellent sound attenuator effect which was not inferior to that of a silencer backdrop with an intermediate layer made of glass fleece.

■ I "Il ..". - I Sl

- 16 -

summary

In the case of a silencer backdrop with a thin plastic protective film covering the absorbent yarn and an outer, mechanically strong, perforated cover, there is a largely sound-permeable, thin intermediate layer 16 consisting of individual plastic threads, which makes contact with the plastic protective film 14 on the outer cover 18 prevented. The plastic threads of the intermediate layer 16 have a [mutual clearance thread distance of Anlagjskontakts the plastic protective foil 1 ^ is sufficiently small as large as possible in view of a good sound permeability of the intermediate layer and in consideration of a prevention. The plastic threads can preferably cross one another and be glued to one another in the intersection area. In addition, they can run in different levels of the intermediate layer or be interwoven. Such an intermediate layer ensures that, while maintaining the sound dampening effect of the backdrop, abrasion and the entrainment of particles in the gas flow are avoided. ^x / in between

Claims (12)

XT --isolation technology and noise protection GmbH, Thadd & usstrafie S, 4830 Gütersloh 1 silencer backdropPatent claim « 1. Silencer backdrop for flowing gases, especially for ventilation and air conditioning systems, with a roughly parallel to the direction of flow to be arranged, plate-shaped, multi-part link body, which has an absorbent core made of porous, for Conces- the absorbent core at its the gas stream: a suitable sound-damping material, such as mineral wool, FER _(a ner reverse side covering protective film, especially made of plastic, and eii & a pull the protective film against the gas flow reversed Selta covering, mechanically solid, perforated, outer cover, such as a perforated plate or wire mesh, with a minimum hole fraction of about 15 %, preferably about 30%, and in which a mat-like, sound-permeable intermediate layer is arranged between the protective film and the outer cover, characterized in that the intermediate layer (15) is a thin-layer spacer made of thin plastic threads (22, 24; 26, 28) formed s 1st, the mutual distances (a, b) to prevent a Contact contacts between the protective film (14) and the outer cover (18) sufficiently small and for good [ 8c: Hall permeability of the intermediate layer (16) as large as possible j, where the distances are smaller, the thinner the f Plastic threads and the more flexible or thinner the protective film are. yy 2. A backdrop according to claim 1, characterized by from individual Fibers consisting of strand-like plastic threads (22, 24; 26, 28) • * »t ϊ · • 41 .1 • · · J · »1 3. A backdrop according to claim 1 or 2, characterized by plastic Threads (22, 24; 26, 28) made of polyester, polyethylene, poly- I vinyl chloride or polyamide. I. 4. backdrop according to one or more of claims 1 to 3, ge I is characterized by plastic threads crossing each other like a grid I den (22, 24; 26, 28). '' 5. A backdrop according to claim 4, characterized by woven or I interwoven Kunetetoff threads (26, 28). 6. The backdrop according to claim 4, characterized in that the I cross and calibrate each other touching plastic thread [ (22.- 24) in adjacent planes of the intermediate sends (16) run. 7. A backdrop according to one or more of claims 1 to 6, characterized by glued to one another at the crossing points, as if welded to one another by heat pressure. 'Plastic threads (22, 24; 26, 28). I 8. backdrop according to one or more of claims 1 to 7, characterized through a thickness of the intermediate layer (16) of: about 0.1 to 1 mm, such as about 0.25 mm. 9. A backdrop according to one or more of claims 1 to 8, characterized by a clear thread spacing (a, b) of about 3 to 10 mm, such as from about 3.5 mm. 10. A backdrop according to one or more of claims 1 to 9, ge I is identified by a measured between the thread centers k Thread spacing of about 4 mm. 11. A backdrop according to one or more of claims 1 to 10, ge | characterized by plastic threads (22, 24; 26, 28) with additional | at least partially flattened, such as oval, cross-section. | 12. A backdrop according to claim 11, characterized in that the ab- \ flattened Kunstatoff threads (22, 24; 26, 28) a transverse sur
Interlayer (16) measured minimum thickness of about 0.15
now and have a maximum thickness of about 0.7 mm measured in the plane of the intermediate layer. > 13 «backdrop according to one or more of claims 1 to 12, ge | features having a thickness of about 25 μ by a covered by the intermediate layer (16) \ plastic film (14) to 30th ί characterized by a single or multi-layer Abeorp- | tion core (10, 12) made of porous material, such as mineral wool,
the same or different density in layers,
by a plastic covering both sides of the absorbent core j Fabric protective film (14) by a mutual abstandshal- \ tender intermediate layer (16) and a double-sided sweeter k cover (18).