SOUND-DEADENING STRUCTURE OF VENT TUBE AND SOUND-DEADENING STRUCTURE OF CASE

摘要

A sound-deadening structure of vent tube and sound-deadening structure of case that realize not only deadening of sound in a wide frequency region but also prevention of any deterioration of ventilation resistance in the vent tube and case. A venthole (11a) is provided on the circumferential wall of a vent tube (11). The circumferential wall of the vent tube (11) is provided with a cover (12) disposed so as to cover the venthole (11a). A baglike body (13) filled with an active carbon (14) is disposed in the space defined by the circumferential wall of the vent tube (11) and the internal wall of the cover (12).