| 摘要 |
PURPOSE:To prevent the consumption of oil from increasing due to introduction of oil into an intake-air passage, by feeding blow-by gas in the intake-air passage upstream of a supercharger during supercharger operation in which variations of the level of oil becomes large due to an increase in engine vibration or vehicle body vibration. CONSTITUTION:A first blow-by gas reduction passage 15 connected at one end to an intake-air passage 12 upstream of a supercharger 10 is connected, in the vicinity of a cap 13b, to an oil filler pipe 13 projected from the top part of an intermediate housing 2b of a rotary piston engine 1. Further, a second blow-by gas reduction passage 20 connected at one end to a low load intake-air passage 5 downstream of a low load throttle valve 5b, is connected in the vicinity of the pipe 13. Further, a purge valve 22 which opens the passage 20 only when negative pressure is detected in a negative passage 21 downstream of the throttle valve 5b or when no supercharging operation is effected, is disposed in the intermediate section of the second blow-by gas reduction passage 20, and during supercharge operation blow-by gas is fed into the intake-air passage 12 from the passage 1. |
