NOISE SUPPRESSOR OF PNEUMATIC VALVES OUTLET Russian patent published in 2017 - IPC F01N1/04 

FIELD: machine engineering.

SUBSTANCE: muffler comprises an inlet branch pipe and an outlet branch pipe formed by at least two transversal partitions located perpendicular to opening axis of the inlet branch pipe, one of which is rigidly fixed to the inlet pipe and the other is made blind and installed with respect to the first one with formation of an end gap, the partitions are fixed along their peripheral part by at least three screws with calibrated washers, a solid screen is rigidly attached to the last partition, in the form of a cup, fastening is performed by means of a bottom coaxial with the partitions, and the side surfaces of the screen form an annular gap with the peripheral part of the partitions. The screen is made of a porous sound absorber. The side surface of the cup is made acoustically lined in the form of rigid and perforated walls, between which there are two layers: a sound-reflecting layer adjacent to the rigid wall, and a sound-absorbing layer adjacent to the perforated wall, at that the layer of the sound-reflecting material is made of composite profile consisting of uniformly distributed hollow tetrahedrons which allow to reflect sound waves incident in all directions. Mineral wool on basalt base is used as a sound-absorbing material.

EFFECT: improved efficiency of noise suppression.

2 dwg