Abstract: A resonator for attenuating pressure pulses is provided. The resonator includes a housing, a divider, a first neck, and a second neck. Walls of the housing form a cavity with a first and second opening. The divider is located in the cavity and cooperates with the housing to form a first and second chamber. The divider is rotatable to change the volume of the first and second chamber. The first neck is located between the first opening and the first chamber, and the second neck is located between the second opening and the second chamber.

Abstract: An in-line resonator for an air induction system of an internal combustion engine is provided. The system includes a resonator housing, an upstream duct, a downstream duct, a conduit, a partition, and a sleeve. The conduit extends through the resonator housing connecting the upstream duct and the downstream duct. The partition is moveable within the resonator housing and divides the housing into an upstream chamber and a downstream chamber. The downstream chamber, the conduit, and the downstream sleeve cooperate to form a first Helmholtz resonator that is in fluid communication with the downstream duct. The upstream chamber, the conduit, and the upstream sleeve cooperate to form a second Helmholtz resonator that is in fluid communication with the upstream duct. Further, a means is provided to axially move the partition to vary the volume of the chambers concurrently with the length and/or area of the passages.

Abstract: An air induction system for inducting air into an engine of an automobile is disclosed. The air induction system has an air cleaner and an air inlet tube. The air cleaner is in fluid communication with the engine of the automobile for filtering intake air inducted into the engine. The air inlet tube is made of a first material and is connected at a first end to the air cleaner and open to ambient air at a second end. The inlet tube has a flexible portion that flexes as a result of internal pressure pulsations during the air induction event. The flexing reduces or eliminates acoustic standing waves that have significant pressure fluctuations at the same location in the air induction system as the flexible portion.

Abstract: The present invention relates to a resonator for attenuating pressure pulsations received through an air passage. A piston-type member is located within a resonator chamber to define first and second volumes. A first port connects the air passage with the first volume, while a second port connects the air passage with the second volume. An actuator is configured to move the piston-type member thereby changing the first and second volumes. By changing the first and second volumes and selectively connecting them to the air passage, the frequency range attenuated by the resonator can be adjusted.

Abstract: The present invention provides a resonator for attenuating acoustic vibration from an air intake passage. The resonator includes a neck, a resonator chamber, a piston-type member, and an actuator. The neck is attached between the air passage and the resonator chamber. The neck has two overlapping portions allowing the neck to extend within the resonator chamber. The piston-type member is located within the resonator chamber and is translated by the actuator to change the volume of the resonator and the neck length. By changing the volume and neck length of the resonator, the frequency attenuated by the resonator can be adjusted.