INTAKE NOISE AMPLIFICATION DEVICE FOR VEHICULAR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To reduce noise of 100 to 200 Hz becoming discomfort booming noise while amplifying intake noise near 400 Hz as harmonious engine noise.SOLUTION: An intake noise amplification device is constituted by including: an inlet side tubular member connected to an intake system of an internal combustion engine; an outlet side tubular member having an extremity end opened outside; and a bellows-like resonance member positioned at an interface part between both tubular members, and a tube length and the like are tuned to amplify intake noise near 400 Hz. An intermediate part of the outlet side tubular member is provided with an expanded tube part 17, and an end part of the expanded tube part 17 is provided with an acoustic absorber 21 of foamed rubber. The acoustic absorber 21 passes noise near 400 Hz and in turn attenuates a band range of 100 to 200 Hz. With this arrangement, booming noise is reduced.SELECTED DRAWING: Figure 4