Abstract: A turbocharger having a turbine with a wastegate, and a compressor including a compressor housing, a compressor wheel, and a wastegate actuator. The turbine wheel includes blades defining an inlet. The compressor housing has an inlet wall leading to the inlet, and a shroud wall surrounding the blades. The actuator includes a base that is integral with the inlet wall, and an electric motor that is attached to the base. The shroud wall forms a first port that is in direct fluid communication with the actuator chamber, and the inlet wall forms a second port that is in direct fluid communication with the actuator chamber. Air from the first port to passes through the actuator housing and out the second port. This airflow convectively cools the working components of the actuator, while the connection of the motor to the inlet wall conductively cools the motor.

Abstract: A variable geometry turbocharger employs multiple vanes in the turbine inlet with a unison ring and integral cast wall in the turbine housing forming the nozzle walls. An actuator rotates the unison ring through a rack and pinion driven crank shaft to move the vanes through a range of vane positions that extends between a hard-stop closed position and a hard-stop open position, and that includes a reference position corresponding to a desired flow condition. A variable geometry turbine controller uses a sensor indicating the actuation position of the actuator to guide the operation of the vanes to the reference position. The controller intermittently directs the actuator to force the vanes to the hard-stop closed and hard-stop open positions, and uses sensor information from those positions to reestablish the reference-position information that the actuator uses to guide the actuation of the vanes.

Abstract: A turbocharger having a turbine with a wastegate, and a compressor including a compressor housing, a compressor wheel, and a wastegate actuator. The turbine wheel includes blades defining an inlet. The compressor housing has an inlet wall leading to the inlet, and a shroud wall surrounding the blades. The actuator includes a base that is integral with the inlet wall, and an electric motor that is attached to the base. The shroud wall forms a first port that is in direct fluid communication with the actuator chamber, and the inlet wall forms a second port that is in direct fluid communication with the actuator chamber. Air from the first port to passes through the actuator housing and out the second port. This airflow convectively cools the working components of the actuator, while the connection of the motor to the inlet wall conductively cools the motor.

Abstract: A variable geometry turbocharger employs multiple vanes in the turbine inlet with a unison ring and integral cast wall in the turbine housing forming the nozzle walls. An actuator rotates the unison ring through a rack and pinion driven crank shaft to move the vanes through a range of vane positions that extends between a hard-stop closed position and a hard-stop open position, and that includes a reference position corresponding to a desired flow condition. A variable geometry turbine controller uses a sensor indicating the actuation position of the actuator to guide the operation of the vanes to the reference position. The controller intermittently directs the actuator to force the vanes to the hard-stop closed and hard-stop open positions, and uses sensor information from those positions to reestablish the reference-position information that the actuator uses to guide the actuation of the vanes.