| 摘要 |
PROBLEM TO BE SOLVED: To protect a gas sensor installed at an air intake pipe of an internal combustion engine from a thermal impact of condensed water contained in intake air, and to maintain the accuracy of detecting a gas component high. SOLUTION: A air-fuel ratio sensor 10 is attached to a vertical pipe wall 30 of an air intake manifold. A cylindrical protection cover 22 is arranged so as to surround a detection part 18. A protrusion amount L of the protection cover 22 to an air intake passage is set so as to cover at least an intake air introduction hole 20. An inner wall 22 of the protection cover 22 is a tapered wall which is contracted in diameter toward a root, a spiral groove 24 is formed at the tapered wall, and a through hole 26 is protrusively formed at the terminal end of the root side of the spiral groove 24. The intake air a intruded into the protection cover 22 is imparted with a swirling force by the spiral groove 24, and a water droplet w contained in the intake air a is made to flow out to the downstream side of the protection cover 22 through the through hole 26. COPYRIGHT: (C)2013,JPO&INPIT |
