| 摘要 |
PROBLEM TO BE SOLVED: To improve fuel consumption by enhancing vaporization of a fuel by suppressing increase of an intake air temperature.SOLUTION: An intake manifold 20 having a plurality of intake pipe portions 44 is composed of a material having heat conductivity lower than that of a cylinder head 16. Intake port formation wall portions 46 configuring a wall surface of an upstream end of an intake port 30 incorporated in the cylinder head 16, are integrally disposed on end portions of the plurality of intake pipe portions 44 connected to the cylinder head 16. The intake port formation wall portions 46 respectively include cylindrical wall portions 50 and projecting wall portions 52. The cylindrical wall portions 50 configure the whole periphery of a wall surface at an upstream side of the intake port 30 with respect to an injection port 4208 of an injector 42. The projecting wall portions 52 project toward a downstream side of the intake port 30 from a place of the cylindrical wall portions 50 positioned at a side opposite to a place in which the injector 42 is disposed, and configure a part of a wall surface of the intake port 30.SELECTED DRAWING: Figure 1 |
