A sound bypass device configured to transmit engine-generated sound pulses from an engine to a sound outlet whilst preventing flow of gases to the sound outlet, the sound bypass device comprising: an input tube configured to conduct the engine-generated sound pulses from the engine; and a sound transmission device connected to the input tube at a first end and to the sound outlet at a second end, the sound transmission device comprising: a first volume connected to the first end, a second volume connected to the second end, and a flexible diaphragm separating the first volume from the second volume and configured to transfer variations in pressure in the first volume to the second volume; wherein the first volume has a cross-sectional area that is greater at the diaphragm than at the first end and the second volume has a cross-sectional area that is greater at the diaphragm than at the second end.

A sound pressure generator includes a tube portion having a flow path extending in a tube axial direction; a rotor having a columnar shape with a column axis extending in a direction intersecting the tube axial direction in the flow path, the rotor configured to generate sound pressure by rotating about the column axis; and a drive unit configured to drive the rotor, wherein a cross-sectional shape of the rotor sectioned across the column axis includes a pointed first tip, a pointed second tip, and a long axis along which the first tip and the second tip are aligned.

A noise abatement system for internal combustion engines comprising: a containment body (12) equipped with an inlet hole (6) for the entry of exhaust gases from an internal combustion engine, a plurality of expansion chambers (10) placed in sequence and separated by parallel dividing partitions (13), each equipped with a through-hole (4) for the passage of gases placing in fluid communication two neighboring expansion chambers (10); said expansion chambers (10) having two opposing through-holes (4), one as gas inlet and one as gas outlet. A rotating shaft (9) is integrated in a rotating turbine (1), along an axis comprising the center of gravity of the expansion chambers (10) up to an opposite end of the containment body (12), said rotating shaft (9) having placed around said axis and on said shaft (9) rotary fins (3) which open and close the through-holes (4) between expansion chambers (10) alternately and generating a swirling movement of the flow of gas entering each expansion chamber (10).

A noise abatement system for internal combustion engines comprising: a containment body (12) equipped with an inlet hole (6) for the entry of exhaust gases from an internal combustion engine, a plurality of expansion chambers (10) placed in sequence and separated by parallel dividing partitions (13), each equipped with a through-hole (4) for the passage of gases placing in fluid communication two neighboring expansion chambers (10); said expansion chambers (10) having two opposing through-holes (4), one as gas inlet and one as gas outlet. A rotating shaft (9) is integrated in a rotating turbine (1), along an axis comprising the center of gravity of the expansion chambers (10) up to an opposite end of the containment body (12), said rotating shaft (9) having placed around said axis and on said shaft (9) rotary fins (3) which open and close the through-holes (4) between expansion chambers (10) alternately and generating a swirling movement of the flow of gas entering each expansion chamber (10).

A timbre-scaled exhaust assembly includes: an acoustic portion including an inlet collector including an entrance duct at a first end of the collector in fluid for receiving an exhaust flow from an internal combustion engine and exit ducts at a second end of the collector in fluid communication with a plurality of non-perforated tuning tubes; an outlet collector including entrance ducts in fluid communication with the plurality of non-perforated tuning tubes and an exit duct in fluid communication with an outlet of the exhaust assembly. The inlet collector splits the exhaust flow from the internal combustion engine into the plurality of tuning tubes such that a plurality of distinct exhaust flows pass through the plurality of tuning tubes and the outlet collector combines the exhaust flow. A combined exhaust flow exits the exhaust system through the exhaust tip.

A mounting assembly for a silencer of an exhauster assembly includes a mounting plate. The mounting plate has an opening configured to receive an exhauster of the exhauster assembly while the exhauster is coupled to a structure of a vehicle at least partially separately from the mounting plate. In addition, the mounting plate has a first side configured to face the structure of the vehicle and a second side configured to face the silencer. The mounting assembly also includes at least one exhauster mounting feature configured to couple the mounting plate to the exhauster. Furthermore, the mounting assembly includes a silencer mounting feature configured to couple the silencer to the mounting plate.

An apparatus and method are provided for a drone elimination muffler to attenuate drone exhibited by engine exhaust systems. The drone elimination muffler comprises a hollow canister having a length and a diameter, and a tuned port comprising a first end connected to the canister and a second end connected to the exhaust system. The canister operates in concert with the tuned port as a dampener configured to substantially attenuate exhaust drone, or resonance, at one or more frequencies of engine operation. A valve is configured to switch the drone elimination muffler between a closed state in which the exhaust system operates without acoustic influence due to the drone elimination muffler, and an open state in which the drone elimination muffler directly influences the acoustic properties of the exhaust system.

An apparatus and method are provided for a drone elimination muffler to attenuate drone exhibited by engine exhaust systems. The drone elimination muffler comprises a hollow canister having a length and a diameter, and a tuned port comprising a first end connected to the canister and a second end connected to the exhaust system. The canister operates in concert with the tuned port as a dampener configured to substantially attenuate exhaust drone, or resonance, at one or more frequencies of engine operation. A valve is configured to switch the drone elimination muffler between a closed state in which the exhaust system operates without acoustic influence due to the drone elimination muffler, and an open state in which the drone elimination muffler directly influences the acoustic properties of the exhaust system.

An intake manifold is provided. A first inlet is structured to receive pressurized intake air from a turbocharger. A second inlet is structured to receive exhaust gas recirculation gas from an exhaust gas recirculation system. A third inlet is structured to receive fuel from a fuel line. A plurality of outlets are structured to be fluidly coupled to an engine. An intake manifold passage extends between each of the first, second, and third inlets, and the plurality of outlets. The intake manifold passage is shaped so as to cause at least two reversals in flow direction of each of the intake air, the exhaust gas recirculation gas, and the fuel through the intake manifold passage so as to improve mixing of each of the intake air, the exhaust gas recirculation gas, and the fuel.

An intake manifold is provided. A first inlet is structured to receive pressurized intake air from a turbocharger. A second inlet is structured to receive exhaust gas recirculation gas from an exhaust gas recirculation system. A third inlet is structured to receive fuel from a fuel line. A plurality of outlets are structured to be fluidly coupled to an engine. An intake manifold passage extends between each of the first, second, and third inlets, and the plurality of outlets. The intake manifold passage is shaped so as to cause at least two reversals in flow direction of each of the intake air, the exhaust gas recirculation gas, and the fuel through the intake manifold passage so as to improve mixing of each of the intake air, the exhaust gas recirculation gas, and the fuel.