| 摘要 |
An exhaust valve assembly includes a flapper valve that is mounted on a shaft for rotation within an exhaust component housing between a closed position, an intermediate position, and an open position. An electric actuator is coupled to the shaft to control movement of the flapper valve. The electric actuator moves the flapper valve to the open position for high speed engine conditions. When engine speeds are lowered, and while all engine cylinders remain active, the electric actuator moves the flapper valve to the intermediate position. Once the flapper valve is in the intermediate position, if an engine cylinder is subsequently deactivated, the electric actuator quickly and quietly moves the flapper valve from the intermediate position to the closed position. |
