CS242897B2 - Sound insulating multilayer plate - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a multilayer sound insulating board.

With the turbulent motorization and industrialization of society, the noise in transport, at the workplace, at home, in the micro- and macro-environment is also increasing. the harmful effects of noise appear not only as occupational diseases, but can also be the cause of numerous immediate dangers.

For example, workplace noise can overlap acoustic warning signals, ie noise can become an immediate cause of injury. The driver of a vehicle with a high noise emission gets tired quickly, his ability to concentrate decreases, which can lead to traffic accidents. Particularly significant is the effect of noise in mines, where disregarding the characteristic rock vibrations can lead to missed rescue and mass disaster.

Nowadays, the most common occupational disease caused by noise, hearing damage, and therefore the protection against noise, ie reduction of noise caused by vehicles and machines, is of great importance.

In fact, there are very few active sound absorbing substances and therefore the possibilities of reducing noise are also limited. In practice, thin plates are most commonly used, but still have good sound attenuating and / or sound absorbing properties.

Sound-absorbing plates are known which consist of one or more surfaces between which different fillers are arranged. Various natural or synthetic fiber materials, compact and spongy synthetic materials are used singly or in combination.

There are multilayer boards that contain both adhesives and fillers. Such a board connection is described, for example, in Hungarian Patent No. 169847, according to which the sound-damping boards consist of at least one structural layer and at least one binding layer. .

In the exemplary embodiments, plates are described which consist of 4 to 5 layers forming the structure and 3 to 4 binder layers and filler containing layers. The filler used is a metal powder having a particle size of 0.4 to 400 microns, in particular aluminum and iron powder.

A sound attenuation of 17.1 to 19.1 dB is achieved at a plate thickness of 8 to 9 mm. In British Patent Nos. 909 838 and 992 008, heavy metal powder is recommended as a filler for multilayer boards.

For example, bismuth and lead powder or bismuth and lead oxide powder and granules are used. As a preference, these plates are said to shift the coincidence frequency of the walls or wall elements to higher frequency regions.

In actual experiments, it has been found that fine-grained bronze or copper chips are more suitable as a filler than the iron and aluminum powder recommended in the aforementioned Hungarian patent. In general, it was possible to achieve a 4 to 5 dB better noise reduction.

The solutions disclosed in the aforementioned British patents have the drawback that they come into consideration only in addition to conventional construction material and their use is limited due to the heavy weight of the plates.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the drawbacks of known designs by providing a sound insulating plate. For a more effective sound attenuation, sound absorption, a plate system has been created consisting of materials of a new kind whose damping effect exceeds the sound attenuation parameters of the prior art solutions.

The system of the plates according to the invention is intended to guarantee sound damping over the widest possible range of frequencies at the lowest possible thickness of these plates.

It has been found that the object can be achieved by means of a sound-absorbing, sound-absorbing and vibration-damping multilayer board comprising bitumen and polystyrene, comprising, as a constraining layer, a fabric, felt, artificial leather, rubber or shrinkable polyvinyl chloride or their a combination of bitumen of synthetic resin or tar, a layer of copper or bronze shavings, a layer of a compact combination of skin powder, optionally containing a softener or a layer of skin powder, bitumen and polystyrene.

As other layers, the board may comprise a layer of copper or bronze chips, or a layer of a porous combination of skin powder or a layer of skin powder, bitumen and polystyrene, or a basalt wadding layer soaked in formaldehyde urea resin. the materials mentioned for the first limiting layer.

In this way, the layered board connection exhibits a good sound-damping effect, both in the low-frequency range of 100 Hz and in the mid-frequency range of about 1000 Hz. It can therefore be used to dampen sound over a wide frequency range.

Des ^for and specified with ^ gr ^ rou ^t UHA ^T OM ^or ad ^e, k ^d YZ is ^d at one of said layers comprises the composition of the powder of the skin, but also in this case gives a flexible product, if this layer is used plasticizer , which is usually used in the leather industry, preferably dibutyl sulfate in an amount of 2 to 8% by weight, preferably 4% by weight, based on the weight of the skin powder composition.

The limiting layers are at least 0.5 mm thick and may, as already mentioned, have a combined composition, for example consisting of a combination of tissue and felt or fleece. The type of limiting layer depends on the area of application of the plates.

For example, a layer consisting of bitumen, synthetic resin or tar can be made of polystyrene-bitumen resin (Tivellan), bitumen and polystyrene or tars of synthetic polystyrene-bitumen resin (Katepox), or a composition comprising bitumen (Terotex) as a major component.

The thickness of this layer is at least 1 mm. This layer of copper or bronze chips attached thereto is at least 2.5 mm thick and consists of copper or bronze chips, preferably about 2 mm long, with a diameter of about 0.8 mm. The second copper or bronze chip layer, if present, has the same parameters.

A skin powder composition of a more compact nature is described in the CS patent specification

251 773. For the purposes described herein, the composition according to Example 1 of the cited patent is particularly suitable, which consists of 6.0 kg of pork crumb, 47.0 kg of urea-formaldehyde resin, 14.0 kg of technical grade granular urea, 3.0 kg blowing agents, 25.5 liters of water and 4.5 liters of phosphoric acid, technical grade, 10%.

The layer consisting of the skin powder composition may optionally contain an emollient. A preferred plasticizer is dibutyl sulfate. Instead of this layer, a layer consisting of a powder of leather, bitumen and polystyrene (for example the aforementioned polysyrene-bitumen resin) may be used, the two components being mixed in a 1: 1 weight ratio. This layer is at most 3 mm thick .

The product according to Example 7 of this specification consists of 5.0 kg of pulp, 44.0 kg of urea-formaldehyde resin, 12.0 kg of granular urea (40%), 0.5 kg of carboxymethyl cellosolve 2.0 kg of wetting agent, 1.5 kg of sodium hydrogen carbonate 5.0 liters of phosphoric acid, technical grade, 10% and 30.0 liters of water (ph = .7).

Instead of the porous skin powder combination, the combination of skin powder, bitumen and polystyrene may be used. Also this layer is at most 3 mm thick.

The basalt wadding layer soaked in formaldehyde urea resin, if any, is at most 4 mm thick. Basalt wadding of appropriate quality and conventional formaldehyde urea resin with a solids content of about 30% are used for the production of this layer.

For example, urea-formaldehyde resin Amikol-65 may be used. Basalt wool consists of fibers with an average length of 50 to 100 mm and a diameter of 0.05 to 0.1 mm.

A preferred embodiment of the multilayer board according to the invention is described with reference to FIG. 2. The limiting layer 21 is 0.3 to 1.3 mm, preferably a 1.0 thick layer of fabric or rubber. The layer 22 consists of bltumen containing polystyrene and is at least 1 mm thick.

It is followed by at least 2.5 mm thick layer 23 of copper chips. The layer 24 is at least 4 mm thick and consists of a mixture of polystyrene-bitumen resin and skin powder prepared in a 1: 1 ratio or a skin powder composition according to Example 1 of CS 251 773, the composition of which has already been mentioned above. .

Layer 25 consists of copper chips; its parameters match those of layer 23. Layer 26 consists of a 1: 1 mixture of polystyrene-bitumen resin and skin powder or a skin powder composition according to Example 7 of the aforementioned patent, the composition of which has also been mentioned above.

It is at least 3 mm thick. The layer 27 is at least 4 mm thick and consists of basalt wool which has been soaked in formaldehyde urea resin. The second confinement layer 28 is a layer of fabric or shrinkable polyvinyl chloride and is at least 0.5 mm thick.

With the sound attenuation plate according to the invention, noise emitting noise sources can be effectively isolated in the frequency range of 63 Hz to 4 kHz. They are suitable for reducing the noise level of cars and trucks, buses, diesel locomotives, marine engines, compressors, mining equipment, economic tractors and other industrial buildings.

Because sound damping boards can be manufactured largely from industrial waste that cannot be recovered and only to a small extent from industrial waste that can be recovered, the cost of producing them is more favorable than the cost of other known sound absorbing substances.

In the manufacture of the sound attenuation plates according to the invention, large amounts of otherwise unrecoverable waste can be recovered.

The invention is further illustrated by the following examples.

Example 1

Multilayer sound damping plate with metal chip coating.

A 0.3 mm thick linen fabric is coated with a 1.5 mm thick layer of a composition containing bitumen as a major component. A 2 mm thick layer of fine-grained bronze chips (0.8 mm, length 2 mm) is poured onto this.

The metal chips are coated with a 7 mm thick layer of crushed leather processed into polystyrene bitumen resin. The layer was allowed to join for several minutes and then a 4 mm thick layer of basalt wadding soaked in synthetic urea-formaldehyde resin was layered. Finally, the board is sealed with a 0.3 mm thick linen fabric layer.

The plate obtained is 15.1 mm thick. Its average sound attenuation is 30.9 dBa.

Example 2

Multilayer sound damping plate with two layers of metal chips

The 0.3 mm thick fabric is coated with a 1.5 mm thick layer of polystyrene-bitumen resin. A 2 mm thick layer of fine-grained metal copper shavings (4 to 5 mm long and 1.5 to 2.5 mm long) is applied to this. 5 to 6 mm thick, cast into the polystyrene-bitumen resin, are poured onto this.

layer of crushed leather

Before this layer is dried, another layer (2 chips) is poured. A 3 mm thick layer of the porous powder combination of CS patent 251,773, the composition described above, is then added.

mm thick) of copper leather according to Example 7

After this layer had been bonded for several minutes, a basalt wadding layer soaked in synthetic urea-formaldehyde resin was formed and allowed to drip a little. Finally, the board was sealed with a 0.4 mm thick artificial leather layer.

This

34.1 dBa.

The sound absorbing plate is 17.2 mm thick. Its average sound attenuation makes the relationship between frequency and sound attenuation shown in Figure 1.

Example 3

Multilayer sound damping plate with outer coating of rubber or shrinkable polyvinyl chloride

The shrinkable polyvinyl chloride sheet is coated with a 1 to 2 mm thick polystyrene bitumen resin coating and then a 2 mm thick copper chip layer (2 mm long, 1.3 to 1.8 mm thick) is poured over a 2 mm thickness.

It is then coated with a mixture of polystyrene-bitumen resin and powder 2 cm thick resin in a thickness of 5 to 10 mm. Again, a layer of 1 to 3 chips is added, which have been slightly wetted with polystyrene bitumen and sealed with a 1 to 3 mm thick rubber foil.

skin (1: 1 mixture ratio) of sprinkled and finally made copper plate

This sound damping plate is 10 to 30 dBA, in the dBA area.

000 Hz is 40 to mm thick, its higher frequencies ie around 1 to 4 kHz achieve sound attenuation in the area

100 to show unambiguously that the noise in a wide frequency range.

Examples with the plate according to the invention can be effectively damped

Claims (7)

BEFORE HAVE INVENTED Multilayer sound-absorbing, sound-absorbing and vibration-damping plate, comprising bitumen and polystyrene, characterized in that it comprises, as a backing layer, a fabric, felt, artificial leather, rubber or shrinkable polyvinyl chloride or combinations thereof, and applied layer layer layer layer of bitumen of synthetic resin or tar, copper or bronze chips, compact combination of skin powder, optionally containing a softener or powder of skin, bitumen and polystyrene of and finally a second constraint layer of one of the materials mentioned for the first constraint layer. 2. Plate according to claim 1, characterized by bronze chips. by containing an additional layer of copper or copper 3. A board according to claim 1, characterized by a skin or layer of skin powder, bitumen and comprising a layer of porous polystyrene powder combination. 4. A plate according to claim 1 comprising a basalt wadding layer soaked in formaldehyde urea resin. 5. A board according to claim 1, characterized in that its limiting layer consists of a fabric or artificial leather, its layer comprising metallic chips of copper chips and its layer containing a skin powder of a skin powder composition. 6. A board as claimed in claim 1, characterized in that it has a layer of 0.3 to 1.3 mm thick fabric or artificial leather, a 1.0 to 3.0 mm thick bitumen layer of synthetic resin or tar, 2. 0 to 4.0 mm thick layer of copper chips, 4.0 to 7.0 mm thick layer of compact skin powder composition, 2.0 to 3.0 mm thick layer of copper chips, 3.0 to 5.0 a layer of a porous skin powder composition, a 4.0 to 6.0 mm layer of basalt wool soaked in urea-formaldehyde resin, and a 0.3 to 1.3 mm layer of fabric or faux leather. 7. A board according to claim 1, wherein the copper chips are 0.5 to 5.0 mm long and have a diameter of less than 2 mm.