Patent ID: 7434558

Claim:
An intake apparatus for an internal combustion engine, comprising: a passage section defining an intake passage; and a throttle valve located in the intake passage, the throttle valve including a rotation shaft, and a plate-shaped valve element arranged to rotate about the rotation shaft, and having a first end and a second end, the throttle valve being opened so that the first end of the valve element is moved in a downstream direction of the intake passage, and that the second end of the valve element is moved in an upstream direction of the intake passage, the passage section including a circumferential wall formed with an expansion chamber recessed radially outwards, the expansion chamber extending partially circumferentially, and being located at a longitudinal position that is downstream of the throttle valve, and that intake air flows passing through the first and second ends of the valve element flow into each other, wherein the expansion chamber is provided in a part of the circumferential wall of the passage section, and located at a circumferential position which is closer to the first end of the valve element than to the second end of the valve element; and wherein the expansion chamber is provided at the circumferential position which is located in a direction inclined at 45° to the rotation shaft from a center of the intake passage.