| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent damage on an opening adjustment mechanism of a nozzle vane even if water accumulated in a turbine housing is frozen during engine stop.SOLUTION: In a case of detecting an operating state of an opening adjustment mechanism of a nozzle vane 4, an actuator 64 is made to operate at a lower drive torque than an ordinary torque to such a degree that components of the opening adjustment mechanism are not damaged even if the opening adjustment mechanism is in a malfunctioning state. If an opening of the nozzle vane 4 does not reach a target opening within determination count time, it is detected that the operating state of the opening adjustment mechanism is not a normal state. In a case of processing for defrosting the opening adjustment mechanism, the actuator 64 is kept operating at the lower torque than the ordinary torque, and it is confirmed whether the opening of the nozzle vane 4 reaches the target opening within the determination count time. During the processing, exhaust gas from an engine (not shown) passes through the nozzle vane 4 and the opening adjustment mechanism thereof. As a result, if the opening adjustment mechanism is in a frosted state, the opening adjustment mechanism can be defrosted by heat of the exhaust gas.</p> |
