| 摘要 |
PURPOSE:To always maximize the thermal efficiency of an engine by controlling the ignition timing an exhaust timing in such a manner that output of an engine is maximized, and controlling the capacity or length of an exhaust pipe according to the temperature of gas in the exhaust pipe. CONSTITUTION:Fuel-air mixture sucked in from a suction port 5 is compressed in a crank chamber to scavenge the interior of a cylinder, and ignition is performed by a spark plug 4. Waste gas is exhausted from an exhaust port 6 and discharged from an exhaust pipe 7. According to various input such as the rotational frequency of an engine, exhaust temperature 11 and so on, a control device 16 controls ignition timing at the spark plug 4, an exhaust timing control valve 8 disposed on the upper part of the exhaust port 6, and an exhaust pipe length adjusting valve 9. At that time, the ignition timing and the exhaust timing are controlled in view of maximizing output of an engine among various control views, and the length of the exhaust pipe is controlled in such a manner that the lower the exhaust gas temperature is, the shorter the exhaust pipe is. An exhaust pipe capacity adjusting device may be provided instead of the exhaust pipe length adjusting valve 9. |
