Adjustable helmholtz resonator

A Helmholtz resonator assembly for an internal combustion engine comprising:

• a housing partially defining a first volume and at least one other volume;
• a first sleeve member disposed within said housing and further defining said first volume and said at least one other volume;
• a second sleeve member movably disposed within said first sleeve member, said second sleeve member being movable between a first position and a second position and defining a passage through which a gas may pass;
• a first and at least one other plurality of orifices defined by said first sleeve member;
• a first and at least one other plurality of orifices defined by said second sleeve member;
• wherein said second sleeve member substantially blocks said first plurality of orifices and said at least one other plurality of orifices defined by said first sleeve member to prevent communication between said first volume and said at least one other volume and said passage when said second sleeve member is in said first position;
• wherein said second sleeve member substantially aligns said first plurality of orifices and said at least one other plurality of orifices defined by said first sleeve member to allow communication between said first volume and said at least one other volume and said passage when said second sleeve member is in said first position;
• wherein said at first plurality of orifices defined by said first sleeve member, said first plurality of orifices defined by said second sleeve member, and said at first volume cooperate to form a first Helmholtz resonator when said first plurality of orifices defined by said first sleeve member is aligned with said first plurality of orifices defined by said second sleeve member;
• and
• wherein said at least one other plurality of orifices defined by said first sleeve member, said at least one other plurality of orifices defined by said second sleeve member, and said at least one other volume cooperate to form at least one other Helmholtz resonator when said at least one other plurality of orifices defined by said first sleeve member is aligned with said at least one other plurality of orifices defined by said second sleeve member.

A Helmholtz resonator assembly comprising:

• a housing partially defining at least one volume;
• a first generally cylindrical sleeve member disposed within said housing and further defining said at least one volume;
• a second generally cylindrical sleeve member generally coaxially disposed within said generally cylindrical first sleeve member and defining a passage through which a gas may pass;
• wherein said second generally cylindrical sleeve member is selectively and variably movable with respect to said first generally cylindrical sleeve member between a first position and a second position;
• at least one orifice defined by said first generally cylindrical sleeve member;
• at least one other orifice defined by said second generally cylindrical sleeve member;
• wherein said second generally cylindrical sleeve member substantially blocks said at least one orifice to prevent communication between said at least one volume and said passage when said second generally cylindrical sleeve member is in said first position;
• wherein said at least one other orifice of said second generally cylindrical sleeve member aligns with said at least one orifice to allow communication between said at least one volume and said passage when said second generally cylindrical sleeve member is in said second position;
• wherein said at least one orifice, said at least one other orifices and said at least one volume cooperate to form at least one Helmholtz resonator when said at least one orifice is aligned with said at least one other orifice of said second generally cylindrical sleeve member;
• an actuator responsive to signals from a controller;
• and
• wherein said actuator is configured to selectively and variably move said second sleeve member between said first position and said second position.