ACOUSTIC CONVERSION DEVICE FOR ACTIVE NOISE CONTROL

摘要

An acoustic conversion device for an active noise control is provided. The acoustic conversion device can effectively suppress or remove noise by controlling variation in a lowest resonance frequency. A volume of a closed space is smaller than an equivalent compliance air volume of a speaker unit. Therefore, motion of a vibration plate, an edge and a damper is suppressed, it is possible to restrain the edge and the damper from being deteriorated with time, variation in lowest resonance frequency can be suppressed, phase of emitted sound can be less prone to be deviated from opposite phase of noise, and it is possible to effectively suppress or remove noise.

主权项

1. An acoustic conversion device for an active noise control comprising:
a speaker unit for emitting sound into a room space of a vehicle; and a closed space-forming unit for forming a closed space, the speaker unit being mounted to the closed space-forming unit, wherein the speaker unit includes a vibration plate and an edge which supports the vibration plate, one surface of the vibration plate emits sound to the room space, and the other surface thereof emits sound to the closed space, and a volume of the closed space is smaller than an equivalent compliance air volume of the speaker unit.