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.

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: A continuously variable Helmholtz resonator for a vehicle air intake system having a vibratory input to the resonator wall to dynamically adjust the cancellation frequency for time-varying acoustical signals, and at least one of mean resonator volume control, mean resonator neck length control, and mean resonator neck diameter control whereby control of both the dynamic and the mean properties of the resonator provides a wide-tuning spectrum and facilitates canceling of time-varying acoustical signals.

Abstract: A continuously variable Helmholtz resonator for a vehicle air intake system having a vibratory input to the resonator wall to dynamically adjust the cancellation frequency for time-varying acoustical signals, and at least one of mean resonator volume control, mean resonator neck length control, and mean resonator neck diameter control whereby control of both the dynamic and the mean properties of the resonator provides a wide tuning spectrum and facilitates canceling of time-varying acoustical signals.

Abstract: A variable tuned telescoping resonator which militates against the emission of noise energy caused by intake air in a vehicle wherein the connector length and the volume of the resonator are varied as a function of engine speed simultaneously to provide attenuation of noise energy over a wide frequency range.

Abstract: A multi-chamber resonator box for a vehicle air intake system, wherein the resonator includes a Helmholtz, an expansion chamber, an annular, and a perforated style resonator to militate against the emission of noise energy caused by intake air.

Abstract: A multi-chamber resonator box for a vehicle air intake system, wherein the resonator includes a Helmholtz, an expansion chamber, an annular, and a perforated style resonator to militate against the emission of noise energy caused by intake air.

Abstract: A noise reduction side-branch reactive silencer for use with the air induction system of an internal combustion engine. The side-branch reactive silencer is contained within a subframe interposed between the engine and a vehicle body. The subframe is a rigid structure and forms a reactive cavity therein. The subframe has a connector for communicating the reactive cavity with the air induction system of the vehicle. The connector is positioned along the subframe in accordance with the desired attenuation frequency.

Abstract: A compact combination engine air cleaner/noise deadener for installation in the engine compartment of a motor vehicle type engine includes a two piece plastic elongated housing that is compact and has an ambient air inlet at one end radially spaced from an air outlet to the engine located on the axis of the housing, the inlet containing a first noise attenuating venturi, the housing having an air filter at the other end connected to the venturi and discharging air into a second convergent-divergent flow control noise attenuating venturi with which is integrated a mass air flow sensor, the venturis being surrounded by a dead air space type resonating chamber that has an inlet concentric with the air outlet so that engine feedback noises and sound waves are trapped in the chamber and dissipated, and any sound waves passing serially into the venturis bounce off the walls of the venturi diffusers to also be dissipated, thus minimizing the transmission of engine feedback noises past the air cleaner.