| 摘要 |
PURPOSE:To permit the superior warming for intake air by connecting the intermediate part of a warm-air suction passage to a heat receiving device covering the outer surface of an intake manifold, in watertight form, in the intake system of an internal combustion engine which is constituted of a cooled-air suction passage and the warm- air suction passage which are selectively used. CONSTITUTION:An intake system including an intake manifold 2 is connected to the upstream side of the cylinder head 1 of a horizontal type internal combustion engine, and an exhaust system including an exhaust manifold 4 is connected to the downstream side, and a cooled-air suction passage 12 and a warm-air suction passage 13 which selectively communicate by a selector valve 25 are installed at the inlet of an air cleaner Ac, and a heat receiving device 15 is installed so as to cover the front surface region of the exhaust manifold 4, keeping a gap 18. In the heat receiving device 15, an inner plate 16 and an outer plate 17 are superposition-jointed at the peripheral edge flange parts 161 and 171, and constituted so that a sealed hot-air chamber 19 is formed inside. The lower edge of the upstream and downstream side passages 131 and 132 of the warm-air suction passage 13 are connected to the inflow port 23 and the effluence port 24 of the chamber 19. |
