Patent attributes
A silencing mechanism of a pneumatic tool, disposed in an exhaust pipe of the pneumatic tool, includes an annular wall extending along the exhaust pipe, enclosing a first space, and having a plurality of first slits whereby the first space and a second space formed between the annular wall and a pipe wall of the exhaust pipe are in communication with each other; and at least one flange disposed around the annular wall and protruding radially to partition the second space into a plurality of segments, wherein the at least one flange each has a plurality of second slits whereby adjacent segments are in communication with each other. A gas current not only flows freely between the first and second spaces through the first slits but also flows within the second space and passes the second slits, thereby reducing noise.