| 摘要 |
PURPOSE: To secure excellent starting performance and excellent exhaust performance in a low speed area while maintaining a low compression ratio, by controlling the closing timing of each intake valve in such timing that it advances in the vicinity of a bottom dead center when an engine is started and is in the low speed area while controlling it in such timing that it lags from the bottom center when the engine approaches to a high speed area. CONSTITUTION: When operating oil discharged from an oil pump 24 is selectively supplied to respective oil pressure chambers 22 of Nos. 1 to 4 air cylinders through rotary valves 30, 31 after being selectively supplied from an accumulator 25 to oil passages 28, 29 through inlet side electromagnetic switching valves 26, 27, each inlet valve 20 is opened in order. While, when operating oil in each oil pressure chamber 22 is selectively made to escape from the oil passages 28, 29 to a tank 35 through outlet side electromagnetic switching valves 33, 34, each inlet valve 20 is closed in order. The outlet side electromagnetic switching valves 33, 34 are controlled so that the closing timing of each inlet valve 20 is controlled in such timing that it advances in the vicinity of a bottom dead center when an engine is started and is in a low speed area while being controlled in such timing that it lags from the bottom dead center when the engine approaches to a high speed area. |
