| 摘要 |
PROBLEM TO BE SOLVED: To improve rigidity, and reduce vibration of an intake manifold effectively by arranging a water jacket part on the bottom surface of a plurality of manifold branch pipes formed by bending in a nearly L-shape so as to form a cooling water passage having a prescribed distance between an intake flange and a surge tank part side. SOLUTION: An intake manifold 4 in the intake device 2 of a four cylinder internal combustion engine is provided with manifold branch pipes 6 (6-1 to 6-4) formed by bending in a nearly L-shape, a surge tank part 8 provided adjacently to the upstream side of the manifold branch pipes 6, and an installing flange 10 provided adjacently to the downstream side thereof. In this case, a water jacket part 14 is arranged on the bottom surface of each manifold branch pipe 6, which is extendedly provided in a prescribed surface range to a part served as the loop of vibration of the intake manifold 4 on the bottom surface of each manifold branch pipe 6, and also which is provided so as to form a cooling water passage 16 having a prescribed distance A nearly horizontally between the installing flange 10 side and the surge tank part 8 side. |
