US Patent 7849960 Silencer

The invention relates to a silencer for an airborne sound conducting pipe system, including a housing enclosing an interior space, an inlet pipe having an outlet within the interior space, a bypass pipe branching off from inlet pipe within the housing and having an outlet, a control element actuated by the gas flow and arranged downstream of bypass pipe on or in the inlet pipe, and at least one outlet pipe having an inlet within the interior space. Furthermore, the interior space is acoustically unseparated in such a manner that the volume of the interior space loaded with the airborne sound is equal with opened and with closed control element.