| 摘要 |
PURPOSE:To utilize the exhaust pulse of the other cylinder and improve the engine performance by setting explosion intervals at uniform intervals so that the opened period of a scavenging port and the start of the opened period of an exhaust port of adjacent cylinders are overlapped in a two-cycle engine having the even number of cylinders. CONSTITUTION:The #2, #3 cylinders are vertically adjacently arranged in the two-cycle serial two-cylinder engine of an outboard engine, and exhaust ports 15, 16 are merged at an exhaust collecting pipe 20. The heights H1, H2 of the #l cylinder are located at the opening/closing timing positions of the exhaust port 15 and a scavenger port 16, and the heights H1', H2' of the #2 cylinder are located at the opening/closing timing positions of the exhaust port 16 and a scavenger port 18. The completion of the opened period of the scavenger port of one adjacent cylinder is overlapped with the start of the closed period of the exhaust port of the other cylinder, and the intake efficiency, torque, and fuel consumption can be improved. |
