| 摘要 |
PURPOSE:To prevent torque shock by providing a first switch-over means for switching over the amount of the supercharging capacity of a supercharger so that it becomes smaller when the engine speed is low, and vice versa, and providing a second switch-over means for switching over the amount of the set max. supercharging pressure in synchronous with the said switching-over. CONSTITUTION:An air intake passage 15 up a serge tank 12 is branched into two branch air intake passages 15A and 15B and a compressor 18a of a small No.1 supercharger 18 is provided in the branch air intake passage 15A. Also, a compressor 20a of a large No.2 supercharger 20 is provided in the air intake passage 15 down the both branch air intake passages 15A and 15B. On the other hand, an exhaust gas passage 23 is branched into two parallel branch exhaust gas passages 23A and 23B directly down a manifold section X and turbines 18b and 20b of the superchargers 18 and 20 are provided in these passages, respectively. A shutter valve 24 is provided directly down the turbine 20b and a waist gate valve 26 is provided in a bypass passage 25 provided so that it bypasses the both turbines 18b and 20b. Both valves 24 and 26 control the air intake device by switching over it synchronously according to the number of rotations of an engine. |
