LT5935B - Noise reducing shutters - Google Patents

Abstract

The invention relates to devices for noise reduction. This invention is designed to reduce noise from air handling units, which take the air from the environment or emits it, and for the devices which must be cooled. For this may be used noise-absorbing blinds with horizontal chipboard panels covered with mineral wool layers and coated textiles. Tables can be tilted for best reduce of prevailing frequencies. Blinds works as principle of noise wave reflection and interference. Sound waves that had fallen into the blind plate are reflected from the surface of the mineral wool layer and from the surface of the plate base, and twice passing the mineral wool layer loses most of its energy. This is repeated several times, depending on the angle of inclination of the plates. After passing the plates sound waves interferes. Noise-absorbing blinds equivalent noise level reduces to 14 dB.

Description

Technical field

BACKGROUND OF THE INVENTION The invention relates to devices for ventilation systems or devices that require ventilation for noise reduction.

State of the art

Noise Reduction Blinds as a Noise Reduction Device, described in U.S. Patent No. 5,168,130, issued December 1992. This Directive shall apply from 1 December 2006, in order to reduce the noise emitted by stationary noise sources which require ventilation or air intake or exhaust. This type of equipment cannot be blinded by sound-absorbing structures, which requires structures that are air-permeable but retain and reduce noise.

The main disadvantage of the prototype is that its noise-reducing horizontal plates are not covered with noise-absorbing material, the plates are fixed in place, and there is no possibility to change their inclination.

The essence of the invention

It is an object of the present invention to provide blinds for reducing the noise emitted by equipment requiring ventilation or exhaust or supply of air, as well as ventilation units that take in or out air. The goal is achieved by making the blinds' horizontal tables moving with a variable inclination of 0 ° to 45 °, of uniform width, covered with 3 cm thick sound absorbing stone wool slabs and textile layer.

Description of the drawing

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 with a general view of the noise-reducing blinds.

Noise reduction blinds include:

1. Horizontal particle boards, 30 cm wide and 1.2 cm thick, that are scattered at different angles and propagate noise waves at different angles. These plates also serve as a base on which a sound absorbing layer of rock wool is installed.

2. A 3 cm wide stone wool layer absorbs the sound waves that fall on them, reducing the noise level.

3. Textile, which strengthens the layer of stone wool, increases its service life and protects it from dust.

4. The frame of the particleboard holds the horizontal plates, which are covered with a layer of stone wool and textiles.

Description of Implementation of the Invention

The present invention relates to a device that requires ventilation or to reducing the noise of ventilation units that receive or supply air.

Noise from equipment is usually reduced by enclosing it with noise-absorbing walls or various screens, but then the noise propagates upwards. However, if the unit needs to be cooled or fed or air intake, fencing the unit with noise walls or screens is no longer possible. The noise level is then reduced by covering the nearest walls near the equipment, if any, with reverberation reducing agents. However, this method does not solve the problem of increased noise. Such devices, instead of noise-absorbing walls or screens, can be covered by proposed noise-absorbing blinds, which are not enclosed and are ventilated by horizontal or angled slabs, while the ventilation systems take in or exhaust air. The noise-absorbing tables are tilted at an angle to reduce noise from the equipment. Depending on the angle of the blinds, the noise isolation of the blinds varies.

The principle of noise-reducing blinds The noise-absorbing blinds operate on the principle of absorption of noise waves. The traveling noise waves encounter an obstacle - a particle board covered with rock wool (Figure 2) (Figure 1). The noise level is reduced because the diffusion and reflection of the sound wave when the sound waves hit the obstacle. Noise waves, when hit by an obstacle, lose some of their energy to cause fluctuations in the blinds (Figure 1). In addition, some of the noise energy is lost when the noise waves penetrate through the stone wool layer (Figure 2) to the blinds tables and, when reflected, return to the wool layer.

Claims (5)

1. Noise-reducing blinds having a frame, horizontal plates, a noise-absorbing layer, characterized in that the noise-reducing blinds have a particleboard frame, in which the particleboard boards with a sound-absorbing layer and covered with reinforcing cloth are movably fixed. 2. Noise shutters according to claim 1, characterized in that the horizontal sound-absorbing slabs are movable and have the possibility of adjusting their inclination angle from 0 ° to 45 ° according to the position of the noise source relative to the noise shutters and the frequencies prevailing. 3. Noise-reducing blinds according to claim 1, characterized in that the horizontal noise-absorbing blinds are of uniform size. 4. Noise reduction blinds according to claim 1, characterized in that the horizontal plates are covered with layers of 3 cm thick stone wool and textile fabric. 5. Noise shutters according to claim 1, characterized in that, depending on the size of the source and the need for higher or lower airflow required, the gap between the plates can be varied.