| 摘要 |
PURPOSE:To lower the specific fuel consumption of an Otto-cycle engine in which a supercharger consisting of at least two pumps connected in parallel with each other is connected to an output shaft of the engine, by employing such an arrangement that the output power of the pumps is transmitted to the output shaft of the engine at the time of low-load operation of the engine and supercharging of intake air is started at the time of high-load operation of the engine. CONSTITUTION:In a supercharger 2 which consists of two pumps 3, 3' and is driven by a driving means selectively according to the operational conditions of an engine 1, the pumps 3, 3' are disposed respectively in intake passages 8, 8' connected in parallel with each other, and supercharged intake air is supplied to the engine 1 via discharge passages 10, 10'. At the time of racing operation of the engine 1, throttle valves 11, 12 are closed completely and a shut-off valve 18 is fully opened so that work is done only the pump 3 and the output power of the pump 3 is transmitted to the engine 1. On the other hand, when the engine output is increased with opening of the throttle valve 12, intake air is supplied also into a work chamber 7' via passage 13-16 and the engine output is increased. With further opening of the throttle valve 12, the throttle valve 11 begins to open and supercharging of the engine 1 is started. |
