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

FIELD: machine building.

SUBSTANCE: tubular combined noise silencer comprises a cylindrical body rigidly connected to the end inlet and outlet nozzles, sound absorber disposed between the cylindrical body and the perforated element and an acoustically transparent material disposed between the perforated element and the sound absorber. On the muffler axis there is a sound-absorbing cylindrical insert, on one of the end faces of the perforated cylindrical insert a cone-shaped cone is fixed, and the cylindrical insert is fixed to the inlet and outlet nozzles by means of at least two stiffeners located in a plane perpendicular to the axis of the muffler. Inside the cylindrical insert there is also a sound absorber. Acoustically transparent material is located between the perforated element of the insert and the sound absorber. Sound absorber is made in the form of a sound-absorbing element of the ring type. Frame of the absorber is made in the form of perforated walls, between which there are layers of sound absorbing material. There are three layers of sound absorbing material. More rigid first layers are made solid, profiled and fixed respectively on external perforated walls. Second layers, softer than the first, are intermittent, and are located with a gap in the focus of the reflecting surfaces of the first layers, and have the form of bodies of revolution in the form of cones connected by 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. Each of the outer perforated walls is rigidly connected to the corresponding second layer by means of vertical fastening elements perpendicular to it, 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. Middle wall, made in the form of a membrane resonant plate, is rigidly connected to the frame by means of a construction sealing foam located in the gaps and cavities of the frame.

EFFECT: efficiency of the noise suppression increases with the use of the invention.

4 cl, 3 dwg