| 摘要 |
PURPOSE:To utilize exhaust gas energy effectively under both high and low speeds by employing a single scroll type supercharger for low rotation and a multi-scroll supercharger for high rotation. CONSTITUTION:A supercharger 23 to be operated under low speed through a changeover valve 35 is constructed into single scroll type supercharger having only one scroll path 23d, and exhaust gas from all cylinders C1-C6 is collected to the scroll path 23d. A supercharger 22 to be operated under high speed is constructed into multi-scroll type supercharger having splitted scroll paths 22d, 22e, where the splitted scroll paths 22d, 22e are coupled respectively with exhaust paths 33A, 33B provided independently for cylinder groups C1-C3, C4-C6 having exhaust strokes which do not overlap each other. Consequently, response of the supercharger 23 is improved under low speed through prevention of temperature drop of exhaust gas and the turbine efficiency of the supercharger 22 is improved under high speed through prevention of interference of exhaust gas. |
