Apparatus for treating flowing working gases particularly to reduce the noise in operation thereof

An apparatus for treating flowing working gases flowing from a gas operating device having a discharge conduit with a plurality of annularly distributed discharge openings for the outflow of the working gases comprising:

• a housing connected around the discharge conduit and over the discharge openings defining a first and at least one other annular flow chamber around the conduit;
• a dividing member in said housing for dividing said first and other annular flow chambers from each other, and defining a constricted flow passage between said first and other chambers;
• an annular resilient valve member overlaying all of the discharge openings and being flexible outwardly of the openings by the pressure of the working gases, said valve member comprising an expandable split ring and an elastic band overlaying said ring, said ring including downwardly extending projections in spaced circumferential locations around its interior which engage into respective ones of the openings;
• said openings and overlaying valve member positioned between a wall of said housing adjacent the conduit and an inlet from said first annular flow chamber to said constricted flow passage formed by an edge of said dividing member;
• said ring, when flexed outwardly into a position spaced from said openings, defining an inlet to said first chamber;
• the space between said ring in its spaced position and the conduit being adjacent said edge of said dividing member which forms the inlet to said constricted flow passage, whereby a toroidal annular vortex flow is formed by working gases in said first chamber and, with a sudden reduction of pressure of said working gases, said valve member closes the discharge openings to prevent a flow of gases from said first chamber into the conduit.