COMBINED NOISE MUFFLER Russian patent published in 2018 - IPC F01N1/04 

FIELD: acoustics.

SUBSTANCE: invention relates to the noise suppression equipment. Noise suppressor contains the cylindrical casing, which is rigidly connected with the end inlet and outlet pipes, with the central partition, the body is internally lined with sound absorbing material, and the central partition is made in the form of a perforated pipe rigidly connected on one side with an inlet pipe, and, on the other hand, with a ring of L-shaped profile forming an annular gap with a circular slit with the inner surface of the body, the gap being filled with a sound-absorbing material, sound-absorbing element, which is lined inside the body, is made in the form of two outer perforated walls and an inner, middle wall, made in the form of a membrane resonant plate, between which are placed layers of sound absorbing material, the 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, and more rigid, first layers are made solid, profiled and fixed respectively on the outer perforated walls, second layers, softer than the first ones, are made intermittent and located with a gap in the focus of the sound reflecting surfaces of the first layers, the second layers have a rotation body shape in the form of cones connected by bases, and the first layers are made of a material with a sound reflecting coefficient greater than its sound absorption coefficient in the form of profiles of conical surfaces that focus the reflected sound on the second layers, and the third sound-absorbing layers are made of foamed sound-absorbing material in the form of a construction sealing foam and are located in gaps and voids formed between the first and second layers, wherein each of the outer perforated walls is rigidly connected to the corresponding second layer by means of vertical fastening elements perpendicular thereto, made in the form of plates, one end of which is rigidly fixed to the outer perforated wall, and the second end is made in the form of clamps covering respectively the rods and tightening them with screws, the rods are made parallel to the perforated walls, and the middle wall, made in the form of a membrane resonant plate, is rigidly connected to the frame by the construction of a sealing foam located in the gaps and cavities of the frame.

EFFECT: higher efficiency of noise suppression.

3 cl, 2 dwg