| 摘要 |
PURPOSE: To adjust a degree of reduction in scavenging air density depending on a load by opening and closing two transfer passages leading to a suction port for scavenging air by means of a dividing valve. CONSTITUTION: In this two-cycle engine 10, a suction port 16 for scavenging and charging is opened on a cylinder 12. Scavenging gas is supplied to the suction port 16 through a higher-temperature transfer passage 20 or a lower- temperature transfer passage 22. The transfer passage 20 is provided with a fin 24 which improves heat transfer from an exhaust port 18, and a dividing valve 26 which opens/closes both the transfer passages 20, 22. The transfer passage 22 is, therefore, shut down by the dividing valve 26 at the time of partial load, and only heated low density scavenging gas is supplied to the cylinder 12. The transfer passage 22 starts opening by the dividing valve 26 with the load increasing, so that part of the cooled scavenging gas is mixed with the heated scavenging gas. When the load reaches maximum power, the transfer passage 20 is shut off by the dividing valve 26, thus it is possible to conduct scavenging by lower-temperature scavenging gas. |
