TUBULAR NOISE SUPPRESSOR FOR CHANNEL FANS Russian patent published in 2018 - IPC F01N1/04 

FIELD: ventilation.

SUBSTANCE: tubular noise suppressor to the channel fans contains the square section body, which is rigidly connected to the end inlet and outlet nozzles, the sound absorber, which is located between the body and the perforated element, and an acoustically transparent material, which is located between the perforated element and the sound absorber. Sound absorber is made in the form of a frame of two outer perforated walls and an inner, middle wall, which is made in the form of a membranous resonant plate. Frame is made symmetrical with respect to the middle wall, which divides it into two congruent parts, each of which has three layers of sound-absorbing material. More rigid first layers are made to be solid, profiled and fixed respectively onto the external perforated walls. Second layers, softer than the first ones, are intermittent and are located with a gap in the focus of the reflecting surfaces of the first layers. Second layers are in the form of cones, which are connected with the bases. Third sound absorbing layers are made of foamed sound-absorbing material in the form of a construction sealing foam and are located in the gaps and voids, which are formed between the first and the second layers. In this case, each of the outer perforated walls is rigidly connected to the corresponding second layer by means of vertical fastening elements that are perpendicular to it and are made in the form of the plates, one end of which is rigidly fixed to the outer perforated wall, and the second end is made in the form of clamps, which cover respectively the rods and tighten them with screws.

EFFECT: when using the invention, noise suppression efficiency is improved.

4 cl, 4 dwg