Air intake apparatus
An air intake apparatus has an air intake port opening outside, and an air intake path communicating the air intake port with a combustion chamber of an engine. For suppressing noise getting out from the air intake port, with respect to walls partitioning the air intake path, an opening is provided at a part of said walls corresponding to an antinode region of resonance mode of standing wave in a full length of the intake path, or at a part of noise pressure level being high in the intake path. The opening is closed with a permeable member and a noise insulating wall is disposed outside the permeable member for suppressing emission of transmitting noise passing through the permeable member. member. Alternatively, a vibration control member for suppressing face-vibration of the permeable member and reducing radiant noise from the permeable member is provided instead of the noise insulating wall.
1. An air intake apparatus comprising:
an air intake duct including an air intake port and adapted for communicating the air intake port with an engine combustion chamber;
an opening in communication with an environment external to the air intake duct for suppressing noise emitted from the air intake port, said opening being formed in a wall of the air intake duct and being provided either at a part of said wall of the air intake duct corresponding to a resonance mode antinode of a standing wave in the air intake duct or in a portion of the air intake duct having a high noise pressure level;
a permeable member closing said opening; and
a noise insulating wall disposed outside the permeable member for suppressing emission of transmitting noise passing through the permeable member.
2. An air intake apparatus according to claim 1 , wherein the permeable member comprises a woven fabric permeable member.
3. An air intake apparatus according to claim 1 , wherein the permeable member comprises a non-woven fabric permeable member.
4. An air intake apparatus comprising:
an air intake duct including an air intake port and adapted for communicating the air intake port with an engine combustion chamber;
an opening in communication with an environment external to the air intake duct for suppressing noise emitted from the air intake port, the opening being formed in a wall of the air intake duct at a location that is downstream from the air intake port;
a permeable member closing the opening; and
a noise insulating wall disposed outside the permeable member for suppressing emission of transmitting noise passing through the permeable member.