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 variable nozzle for a turbocharger (10) has a nozzle ring (138) supporting an array of vanes (134) that are variable in setting angle. The nozzle ring (138) is rotationally oriented and fixed in position by a plurality of circumferentially spaced, radially outwardly extending locating members (170) that engage corresponding locating grooves (159) in a flange member (157) of the turbocharger.

Abstract: An exemplary multi-piece bearing for a turbocharger includes a cylindrical piece that has a coefficient of thermal expansion, opposing ends and an outer surface and an inner surface that extend between the opposing ends where the outer surface includes one or more lubricant openings; an end piece that has a different coefficient of thermal expansion and a face where the face includes one or more lubricant openings; and lubricant passages formed by the cylindrical piece and the end piece for passage of lubricant between the one or more lubricant openings of the outer surface of the cylindrical piece and the one or more lubricant openings of the face of the end piece. As described herein, such an exemplary multi-piece bearing can, upon selection of coefficients of thermal expansion, help maintain axial clearances between various components during operation of a turbocharger. Other exemplary bearings, arrangements and methods are also disclosed.

Abstract: A variable nozzle for a turbocharger (10) has a nozzle ring (138) supporting an array of vanes (134) that are variable in setting angle. The nozzle ring (138) is rotationally oriented and fixed in position by a plurality of circumferentially spaced, radially outwardly extending locating members (170) that engage corresponding locating grooves (159) in a flange member (157) of the turbocharger.

Abstract: An exemplary center housing for a turbocharger includes a compressor end and a turbine end and a through bore that includes a turbine end opening for receiving a bearing cartridge and shaft subassembly. In an assembly, a turbine end shaft portion of the subassembly can have an outer diameter approximately equal to or greater than an outer diameter of the bearing cartridge. The turbine end shaft portion can include grooves where each groove is configured to seat a seal ring. Various other exemplary devices, systems, methods, etc., are also disclosed.

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.