SHOP VACUUM CLEANER NOISE SUPPRESSOR Russian patent published in 2017 - IPC F01N1/00 

FIELD: machine engineering.

SUBSTANCE: suppressor includes a housing, consisting of a cylinder shell, rigidly connected to the end circular plates with inlet and outlet nozzles. At least three reactive chambers, formed by the circular discs with holes, are mounted perpendicularly to the direction of aerodynamic flow motion in the housing. The holes in the discs are alternately misaligned relative to the housing axis, so that the holes in two adjacent disks don't coincide. Three serially connected reactive chambers are coupled to the inlet housing nozzle, the combined and sound absorbing chamber is located successively in axial alignment to the housing. The combined chamber is formed with the discs, connected together by a central sleeve, coaxial to cylindrical shell, and to the inner surface, lined with sound absorbing material. One of the discs, facing towards the inlet nozzle, performed perforated and is lined with sound-absorbing element, which is mounted also on the discs with holes, forming the reactive chambers, and the sound absorbing chamber is formed by the cylindrical shell, the end circular plate with the outlet nozzle and the disc with a central hole, coaxial with the central sleeve of the combined chamber. The inner surface of the sound absorbing chamber is lined with sound-absorbing ring element, mounted coaxially with the cylindrical body, and a circular plate with the outlet nozzle and the disc with a central hole, lined with sound-absorbing circular element, the housing is made of structural materials coated on its surface from one or both sides with a soft vibration damping material. Sound-absorbing ring elements are mounted coaxially to the cylindrical body, in the chambers, each of the elements is designed in the form of rigid and perforated walls, between which two layers are positioned: a reflecting layer adjacent to the rigid wall and sound absorbing layer adjacent to the perforated wall.

EFFECT: improved efficiency of noise suppression.

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