| 摘要 |
<p>PURPOSE:To prevent overspeed securely by controlling the opening of a waste gate valve in a bypass passage for connecting inlet and outlet of a turbine to each other when the turbine speed in a turbocharger is over a specified limit even if the engine boost pressure is less than a specified limit. CONSTITUTION:A turbocharger 9 mounted on a diesel engine 2 is provided with a turbine 10 driven by the exhaust gas from an exhaust pipe 6 and a compressor 12 for supercharging to an air intake pipe 4 by driving the turbine 10. On the other hand, the inlet and outlet of the turbine 10 are connected to each other by a bypass passage 24, and a waste gate valve 26 as an actuator opened and closed drivingly by a magnetic valve 28 is located at the inlet. In this case, an engine boost pressure and a turbine speed are detected by a boost sensor 29 and a position sensor 30, respectively. Even if the engine boost pressure is less than a specified limit, when the turbine speed is over a specified limit, opening of the waste gate valve 26 is controlled by a controller 34.</p> |
