LT6593B - Noise-reducing and air-circulating blinds covered with rubber granulate - Google Patents

Abstract

The invention is intended to reduce the noise of installations requiring air circulation or cooling. Using a uniform 30 cm wide plate and fitting it in the frame with possibility to change the angle of their pitch, a construction with a good sound absorption and the same good air permeability required for the devices has been developed. The construction works on the principle of absorption and interference. The noise wave is faced with plates of the blinds covered with a rubber granulate layer on both sides. In the event of a collision, part of the noise energy is absorbed, part of it is reflected. Due to the design characteristics, it repeats itself several times, depending on the angle of the plates. Depending on the slope angle of the plates, the blinds reduces equivalent noise level up to 12 dB, regardless of the initial noise level, but not lower than the background noise level. The aerodynamic properties of the construction have been verified by simulation.

Description

TECHNICAL FIELD

The invention relates to devices for reducing the noise emitted by ventilation systems or devices requiring ventilation.

BACKGROUND OF THE INVENTION

Noise reduction blinds as a noise reduction device are described in U.S. Pat. No. 005168130 A, published in 1992. December 1 The purpose of the blinds is to reduce noise from stationary noise sources that require ventilation or air intake-exhaust. This type of equipment cannot be blindly covered with sound-absorbing structures, so structures that allow air to pass through but retain and reduce noise are needed.

Also, noise-reducing blinds described in Lithuanian patent no. 5935, published in 2013. differs from the first in that the plates can change their angle of inclination and are covered with a sound-absorbing material.

The disadvantage of the first prototype is that the blind plates are fixed, so it is not possible to change their tilt angle. Also, the plates are not covered with sound-absorbing material.

The disadvantage of the second prototype is that the construction boards are made of particle board. A glass wool board was used as the sound-absorbing material. Such a construction is not suitable for outdoor use because the materials used are not resistant to moisture.

SUMMARY OF THE INVENTION

The object of the invention is to provide blinds for reducing the noise of devices which require air exhaust-supply or ventilation. The structure must be able to operate both indoors and outdoors. To achieve the goal, 30 cm wide metal plates were used, which were glued on both sides with 1 cm thick rubber granulate plates. The rubber granules that make up the rubber granule do not absorb moisture and do not lose their ability to absorb noise, so they can be used outdoors. The panels are mounted in the frame so that they can be tilted from 0 ° to 45 ° (Fig. 1).

DESCRIPTION OF THE DRAWING

To illustrate the invention, a drawing is shown in FIG. 1 with an overall view of the noise-reducing and air-permeable blinds.

Noise-reducing and breathable blinds include:

1. Horizontal stainless steel plates 30 cm wide and 2 mm thick are mounted at an adjustable angle.

2. 1 cm thick rubber granulate slabs glued to the slab on both sides

3. Frame of plastic composite.

DESCRIPTION OF IMPLEMENTATION OF THE INVENTION

The invention relates to the reduction of noise emitted by devices which require ventilation or by ventilation units which supply and supply air.

Various constructions are often used to reduce the noise of equipment that requires air supply-exhaust or ventilation - acoustic screens, curtains, hoods. Such constructions are often used to isolate the noise emanating from ventilation equipment located on the roofs of buildings, as well as to reduce the noise emitted by transformers, generators. However, there is often the problem that the noise passes through the top of the wall and there is no way to increase its height. Also, not all devices can be blindly covered with a hood, as their operation requires free movement of air. Therefore, the proposed construction can be used to reduce the noise of such devices, which is not closed, but the plates, which can be tilted at an appropriate angle, do not allow the noise to spread freely in the environment. In order to minimize the noise emitted by such devices, different angles of inclination of the plates can be chosen, which will change the acoustic properties of the structure.

PRINCIPLE OF OPERATION OF NOISE REDUCING BLINDS

Blind panels made of stainless steel covered with rubber granulate panels. The granulate is produced by recycling car tires by ozonation. This method differs from the simple one in that, thanks to ozone, the rubber separates from metal and plastic cords much more easily, and as a result no metal or plastic residues remain in the raw material. The rubber granulate is mechanically and chemically devulcanized by converting it into a reclaim rubber powder RRP (Reclaim Rubber Powder) or a reclaim rubber mass RRM (Reclaim Rubber Mass).

Rubber granulate, due to its structure and porous structure, has good sound absorption.

The structure covered with rubber granulate panels acts by wave absorption. The principle of operation of the structure is based on the fact that the propagating waves collide with the structural plates covered with rubber granulate, which due to its acoustic properties absorbs part of the propagating noise. The noise passing through the granulate layer collides with a metal plate which, due to its structure, transmits part of the noise and reflects the other part. The reflected noise is again absorbed by the granulate layer, and the noise wave passing through the metal plate collides with another layer of rubber granulate and is re-absorbed. Due to this design of the blinds, depending on the angle of inclination of the panels, the equivalent noise level can be reduced to 12 dB, regardless of the initial noise level, but not below the background noise level.

Claims (4)

DEFINITION DEFINITION 1. Noise-reducing and air-borne blinds having a frame, horizontal plates, a noise-absorbing layer, characterized in that the noise-reducing blinds have a plastic composite frame in which the stainless steel plates are coated with a sound-absorbing layer consisting of a rubber granulate. 2. Blinds according to claim 1, characterized in that the noise-absorbing horizontal plates are fixed in such a way that they can rotate by changing the heeling angle from 0 ° to 45 ° as required, depending on the position of the noise source, in relation to the noise-reducing blinds. 3. Blinds according to claim 1, characterized in that the horizontal plates are coated with a rubber granulate layer which, due to its structure, does not absorb moisture and does not lose its ability to absorb noise and can therefore be used outdoors. 4. Blinds according to claim 1, characterized in that the gap between the plates can be varied according to the dimensions of the noise source and necessary to pass the air flow.