The invention relates to an air cleaner housing for a vehicle, comprising an outer and an inner circumferential wall, and a space therebetween adapted to house at least one filter element for filtering air, wherein the inner circumferential wall is provided with openings to allow filtered air to pass radially inwardly through the inner circumferential wall. The air cleaner housing comprises a first end and an open second end for fluidly connecting the air cleaner housing to a turbo, the open second end being located opposite the first end. The air cleaner housing comprises a resonator, wherein the entire resonator is encircled by the inner circumferential wall such that air entering through the inner circumferential wall passes on the outside of the resonator to and through the open second end.

A rectification structural body includes an inlet port into which air from an air cleaner flows, an outlet port from which air flows out toward an airflow sensor, and a chamber provided between the inlet port and the outlet port. The inlet port and the outlet port are provided in such directions and at such positions that an air flow is bent in the chamber. The chamber includes two cases of a first case and a second case, the chamber being divided into the two cases.

A pre-cleaner for an internal combustion engine is arranged in an intake passage of the internal combustion engine at an upstream side of a filter of an air cleaner. The pre-cleaner includes a casing that includes a cylindrical side wall and swirl generation vanes that swirl intake air about an axis of the casing. The side wall has a portion located next to an upstream side of the swirl generation vanes that is formed from an air-permeable fibrous molded body.

The invention relates to a filter element for mounting in an air cleaner housing of a vehicle. The filter element comprises a circumferential filtering wall through which air is allowed to enter. The filter element also comprises a first end and an open second end for fluidly connecting the filter element to a turbo. The open second end is located opposite the first end. The circumferential filtering wall extends from the first end towards the open second end. The filter element further comprises a resonator. The entire resonator is encircled by the circumferential filtering wall such that air entering through the circumferential filtering wall passes on the outside of the resonator to and through the open second end.

An air cleaner for vehicles includes: a case having an inlet, through which outside air is introduced, and an outlet, through which filtered air is discharged; and a filter installed in an inner space of the case, configured to filter the outside air introduced through the inlet, and including a filtration member, wherein the filtration member is formed in an “∩” shape open downwards and is configured to allow the outside air to pass therethrough in a downward direction and in a lateral direction.

An apparatus of amplifying sound waves may include a metamaterial structure having a metamaterial inside thereof, an inlet through which air flows into the metamaterial structure, and a penetration portion formed to penetrate a portion of one side of the metamaterial structure, a membrane member coupled to the penetration portion, and a resonance member surrounding the membrane member and coupled to the metamaterial structure and including a space inside thereof and a discharge port fluidically communicating with an outside thereof and the internal space.

An air cleaner for a vehicle includes a case having an air inlet pipe and an air outlet pipe. A cover is removably attached to the case for covering an open top portion of the case. With the cover attached to the case an interior of the air cleaner defines a flow passage directed through the air cleaner from the air inlet pipe to the air outlet pipe. A filter element is received in the interior and is arranged over the flow passage. The flow passage immediately downstream of the filter element includes an elbow-shaped section for redirecting airflow from the filter element toward the air outlet pipe. The elbow-shaped section is provided with at least one first guide rib shaped correspondingly to the elbow-shaped section. The flow passage upstream of the air outlet pipe defines a branching section formed as an acoustic resonator for reducing air intake noise.

An intake system of an engine is provided, which includes a first passage provided to an engine bay, for leading fresh air to the engine, a second passage branched from the first passage and extending toward a cabin, and an intake noise increasing device provided to the second passage. The intake noise increasing device has a cylindrical bellows part, a vibrating membrane formed integrally with the bellows part to close a first opening of the bellows part, and an outer circumferential case provided to cover an outer circumference of the bellows part and configured to allow the expansion and contraction of the bellows part therein. The second passage has a deriving passage section connected to a part of the outer circumferential case on a first opening side and extending toward the cabin. The deriving passage section is disposed to be lowered while separating from the intake noise increasing device.

An apparatus for reducing flow noise of an air intake system of a vehicle is provided as an assembly of a body member and a cover member. An acoustic metamaterial unit includes a chamber having a predetermined size, an inlet flow path, and an outlet flow path provided therein and is connected to a pipe of an air intake system. The apparatus advantageously reduces or removes high-frequency flow noise occurring in a turbocharger by using the acoustic metamaterial unit. The size and shape of the acoustic metamaterial unit is standardized such that the acoustic metamaterial unit is used compatibly regardless of the type of vehicles, which can make it possible to advantageously reduce costs and improve salability.

An air intake duct includes a peripheral wall, which is formed by a compressed fiber portion made of a compression molded fiber material. The compressed fiber portion includes high-compression portions having a high compression ratio and low-compression portions having a relatively low compression ratio. The high-compression portions include circumferentially extending sections. Each circumferentially extending section is located in a plane that is perpendicular to an extension direction of the peripheral wall with part of the circumferentially extending section disposed between the low-compression portions. Each circumferentially extending section extends continuously over the entire circumference of the peripheral wall.