| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem in which in a conventional flow rate measurement device, the position of the final end of a curved surface part, serving as a release point for external air flowing along the external face of a sensor body outside a bypass passage, is apart from the exit of the bypass passage, effect in reducing the measurement error of a flow rate sensor with respect to an intake air drift, which has arisen upstream of a housing, is insufficient.SOLUTION: In an AFM3, a projecting curved face part 41 and a projection fin 42 are provided on the external face of a bypass housing 5. Thereby, external intake air flowing along the external face of the projecting curved face part 41 reaches the exit end of a bypass passage 9 without being released in a position apart from the passage exit 12 of the bypass passage 9. Consequently, pressure right after downstream from the passage exit 12 is stabilized, thus reducing a change in the measurement value of a flow rate in the flow rate detection part of a flow rate sensor with respect to an intake air drift which has arisen upstream from the bypass housing 5. |
