Speaker retention assembly for an active noise control system

#The present invention relates to an air introduction system, and more particularly to an active noise control speaker mounting arrangement.

#Manufacturers have employed active and passive methods to reduce engine noise within the passenger compartment. Such noise frequently emanates from the engine, travels through the air induction system and emanates out of an inlet of the air intake into the passenger compartment.

#Active systems use a speaker to create a canceling sound that attenuates engine noise. The sound created is out of phase with the engine noise and combines with this noise to result in its reduction. Generally, this sound is generated in proximity to the inlet of the air induction system. In one such system, a control unit, such as a digital signal processor, obtains data from the vehicle engine, creates a predictive model of engine noise, and thereby generates the appropriate cancellation signal based on the results of this model. This signal is then transmitted to the speaker, which transforms this signal into a canceling sound. Because the control unit may not perfectly model engine noise, an error microphone is placed in proximity to the intake of the air induction system to determine if engine noise need be further attenuated.

#The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:

#FIG. 1 is a general schematic view of an air introduction system according to the present invention;

#FIG. 2 is general sectional view taken along a duct axis of an air introduction body having an active noise control speaker mounted within a duct;

#FIG. 1 illustrates a general schematic view of an air introduction system 10 for a vehicle 12. Preferably, the air introduction system 10 includes an air introduction body 14 mounted adjacent a vehicle body component 16 such as a vehicle bumper. The air introduction body 14 intakes ambient air to communicate airflow to an engine 18 through a duct 19. As known, noise and vibration from the engine 18 emanates through the air introduction system 10. As generally known, noise and vibration from the engine 18 emanates through duct (19) of the air introduction system 10.

#An active noise control system 22 is preferably mounted adjacent an inlet 20 to control engine noise which is radiated through the air introduction system 10. The active noise control system 22 preferably includes a microphone 24 mounted to a support structure 26 and a speaker assembly 28 is mounted within the duct 19 through which engine noise and vibration (illustrated schematically by arrow N) are communicated.

#Referring to FIG. 2, a cross-section of the speaker assembly 28 is illustrated along the length of duct 19. Speaker housing supports 30 are mounted within the duct 19 to support a speaker housing 32 along an axis A which is defined along the length of duct 19. The speaker housing 32 is preferably shaped to provide minimal drag and to minimize the annular gap G between the housing 32 and duct 19. A speaker 34 is supported by a speaker support ring 36 which is mounted to the speaker housing 32. Preferably, the entire periphery of the speaker support ring 36 (also illustrated in FIG. 3) engages the housing 32 to maximize acoustic coupling between the speaker 34 and the engine noise and vibration N. A speaker protection cone 38 mounts to the speaker housing 32 downstream of the engine noise and vibration N to further protect the speaker 34 within the speaker housing 32.