Abstract: A variable-nozzle assembly for a turbocharger includes a generally annular nozzle ring and an array of vanes rotatably mounted to the nozzle ring such that the vanes can be pivoted about their axes for regulating exhaust gas flow to the turbine wheel. A unison ring engages vane arms that are affixed to axles of the vanes, such that rotation of the unison ring causes the vanes to pivot between a closed position and an open position. The vanes have proximal ends that are adjacent a face of the nozzle ring. A vane sealing member is supported on the nozzle ring and has a portion disposed between the proximal ends of the vanes and the face of the nozzle ring. The unison ring includes cams that engage cam followers. Rotational movement of the unison ring causes the cam followers to be moved axially and thereby urge the vane sealing member against the proximal ends of the vanes.

Abstract: A turbocharger includes a variable-nozzle assembly that includes an insert having a tubular portion received into a stepped bore of a turbine housing and having a nozzle portion extending radially out from one end of the tubular portion, and a generally annular nozzle ring axially spaced from the nozzle portion and an array of vanes rotatably mounted to the nozzle ring. Sealing of the interface between the tubular portion of the insert and the turbine housing is provided by a sealing ring formed as a generally annular body having a U- or V-shaped cross-section oriented such that an open side of the U- or V-shaped cross-section faces in a radial direction. The U- or V-shaped cross-section defines two opposing legs, one of the legs being engaged against an end face of the tubular portion of the insert and the other leg being engaged against an upstream-facing step surface of the turbine housing bore.

Abstract: A method of operating a turbocharger is provided, wherein the turbocharger comprises a compressor for compressing inlet air to be supplied to an internal combustion engine and an exhaust gas turbine for driving said compressor. The turbocharger further comprises an electric motor for driving said compressor operable by an electric supply system including an alternator and an electric energy storage device. A connection between said alternator and said electric energy storage device is disconnectable by a switch. According to the present invention, the method comprises the following steps: detecting a transient condition, wherein said internal combustion engine is required to be accelerated; supplying electric energy to said electric motor only from said electric energy storage device at the beginning of said transient condition until a predetermined state is reached; supplying electric energy to said electric motor from the electric supply system after said predetermined state is reached.

Abstract: A turbocharger housing includes a main body for bearing a shaft for carrying a turbine wheel and a compressor wheel, and a seal portion to seal a clearance between the shaft and the turbocharger housing, where the seal portion is formed by an insert being fitted to the main body, where the insert includes a passage for supplying a fluid to the seal portion.

Abstract: A variable-nozzle assembly comprises a nozzle ring and an array of vanes circumferentially spaced about the nozzle ring and rotatably mounted to the nozzle ring such that the vanes are variable in setting angle, and an insert having a tubular portion and an annular nozzle portion extending generally radially out from one end of the tubular portion. A plurality of axially extending holes extend through a thickness of the nozzle portion. A plurality of spacers have first ends joined to the nozzle ring, opposite second ends of the spacers being engaged in the holes and secured to the nozzle portion by welds formed at the second surface. An annular groove is defined in the second surface of the nozzle portion radially inward of and proximate to the holes. Alternatively or additionally, discrete recesses are formed in the second surface adjacent the holes. The groove and/or recesses facilitate weld penetration.

Abstract: Disclosed are retainers for a turbocharger. In one embodiment, the retainer includes a generally annular body that defines a bore and one or more channels. The bore is generally directed along a central axis of the body and can be configured to mate with a nose of a center housing of a turbocharger. The channels can be configured to accommodate vanes associated with a cartridge assembly of the turbocharger. One or more legs may extend from the retainer body and may be configured to mate with and locate the retainer relative to a cartridge assembly for the turbocharger. The retainer can also include a concave portion disposed around a perimeter of the body. The concave portion and the body may be together configured to act as a spring when the retainer is mechanically loaded in a direction having a component parallel to the central axis. Also disclosed are corresponding turbochargers.

Abstract: A variable-vane assembly for a variable nozzle turbine comprises a nozzle ring supporting a plurality of vanes affixed to vane arms that are engaged in recesses in the inner edge of a unison ring. The unison ring is rotatable about the axis of the nozzle ring so as to pivot the vane arms, thereby pivoting the vanes in unison. The unison ring is radially restrained by a combination of radial guide rollers and fixed axial-radial guide pins secured to the nozzle ring, and is axially restrained by one or more axial stops affixed to the nozzle ring.

Abstract: A turbocharger assembly comprises a variable-vane assembly. The variable-vane assembly includes a unison ring with vane arms and/or a main-arm which adjust the setting angle of vanes. Vane arm-engaging elements and main-arm-engaging elements in the unison ring engage ends of the vane arms and the main-arm, respectively. Each vane arm-engaging element comprises an inner contact surface that engages an outer contact surface of the respective vane arm. The main-arm-engaging element comprises an inner actuation surface that engages an outer actuation surface of the main-arm. The inner contact surface and the outer contact surface and/or the inner actuation surface and the outer actuation surface may comprise conjugate curve profiles, such as involute curve profiles based on the involute of a circle. Use of conjugate curve profiles may result in rolling movement between the unison ring and vane arms and/or main arm, which may reduce friction occurring during pivoting of the vanes.

Abstract: A variable-vane cartridge mechanism for a turbocharger is assembled from a nozzle ring, an insert that engages a turbine housing bore, and a plurality of spacers. Holes larger in diameter than the spacers are formed in the nozzle ring and a nozzle portion of the insert, such that the spacers fit loosely in the holes. A locating fixture is engaged with the nozzle ring and insert for precisely locating these parts radially (and optionally also axially) with respect to each other; the spacers can move within the holes as needed to allow the positions of the parts to be adjusted. Once located relative to each other, the nozzle ring and insert are fixed in the desired relative positions by affixing the spacers to them, such as by welding.

Abstract: A turbocharger turbine containing a separate insert affixed within the housing. The insert is of a stamped metal configuration, and forms at least a portion of inlet passageway outer wall. An axial discontinuity is machined into the inlet passageway outer wall, the axial discontinuity being characterized by a size and location to direct airflow away from the blade-gap zone over at least part of the range of flow conditions. The inlet passageway may be either larger or smaller upstream of the axial discontinuity.

Abstract: A turbocharger with a variable nozzle includes a pin mounted in the center housing and extending axially therefrom and engaged in a hole in the nozzle ring to orient the nozzle ring rotationally relative to the center housing. A portion of a length of the pin has a substantially greater compliance than the remainder of the length such that the pin has a flexible tip that engages the hole in the nozzle ring. The flexible tip reduces constraint of thermal deformation of the nozzle ring. The pin portion of greater compliance can be a section of the tube that is slit and expanded. The turbocharger can also include a one-piece locator and heat shield having a locating portion abutting the center housing and the nozzle ring for radially locating the nozzle ring relative to the center housing, and having a shield portion shielding the center housing from hot exhaust gas.

Abstract: A variable-vane assembly for a variable nozzle turbine comprises a nozzle ring supporting a plurality of vanes affixed to vane arms that are engaged in recesses in the inner edge of a unison ring. The unison ring is rotatable about the axis of the nozzle ring so as to pivot the vane arms, thereby pivoting the vanes in unison. A plurality of guide pins for the unison ring are inserted into apertures in the nozzle ring and are rigidly affixed therein such that the guide pins are non-rotatably secured to the nozzle ring with a guide portion of each guide pin projecting axially from the face of the nozzle ring. Each guide portion defines a shoulder radially overlapping the inner edge of the unison ring such that the unison ring is restrained by the guide pins against excessive movement in both radial and axial directions.

Abstract: An exemplary flow path for an electrically assisted turbocharger (220) includes a first opening to an air intake path (114) of an engine (110), the first opening positioned downstream from a compressor (224) of the turbocharger (220); a second opening to an exhaust path (116) of an engine (110), the second opening positioned upstream from the turbine (226) of the turbocharger (220); and a valve (229) controllable by a controller (240, 150, 160) wherein the controller (240, 150, 160) includes control logic for controlling the valve (229) and for controlling an electric motor (228) of the electrically assisted turbocharger (220). Various other exemplary devices, methods, systems, etc., are also disclosed.

Abstract: A turbocharger having a turbine housing defining a chamber for receiving exhaust gas, and a nozzle leading from the chamber. Exhaust gas flows from the nozzle through a turbine wheel in the chamber and changes direction from a radially inward direction in the nozzle to an axial direction downstream of the turbine wheel. A divider in the nozzle divides the nozzle into first-stage and second-stage nozzles. The divider has an upstream surface to guide exhaust gas through the first-stage nozzle and an opposite downstream surface to guide exhaust gas flowing through the second-stage nozzle. An axially slidable tubular piston, disposed in the turbine housing, has a radially inner surface extending along the axial direction and a non-flat upstream end surface. The piston also includes a curved flow-guiding surface causing the exhaust gas to change direction. In a closed position, the piston abuts the divider to close the second-stage nozzle.

Abstract: A variable nozzle device including an annular nozzle passage formed by a gap between two opposing wall members and at least one vane rotatably supported in the nozzle passage. The vane is formed by a strip of sheet metal contoured to have an outer aerodynamic profile, and having a hollow interior with surfaces mimicking the outer profile. The vane is affixed to a shaft having a wind-stream portion forming two contact surfaces that conformingly receive opposing portions of the interior surfaces.

Abstract: A variable-vane assembly for a variable nozzle turbine comprises a nozzle ring supporting a plurality of vanes affixed to vane arms that are engaged in recesses in the inner edge of a unison ring. The unison ring is rotatable about the axis of the nozzle ring so as to pivot the vane arms, thereby pivoting the vanes in unison. A plurality of radial-axial guide pins for the unison ring are inserted into apertures in the nozzle ring and are rigidly affixed therein such that the radial-axial guide pins are non-rotatably secured to the nozzle ring with a guide portion of each radial-axial guide pin projecting axially from the face of the nozzle ring. Each guide portion defines a groove for receiving the inner edge of the unison ring such that the unison ring is restrained by the radial-axial guide pins against excessive movement in both radial and axial directions.

Abstract: A turbocharger includes a thin-walled insert installed in the bore of the turbine housing. The insert is generally ring-shaped and is radially resilient. The insert can be made of sheet metal formed into a ring shape, and in some embodiments is a split ring. A piston is axially slidable in the bore for varying the size of the turbine nozzle. The outer surface of the piston slides against the inner surface of the insert, and in preferred embodiments a piston ring that encircles the piston engages the inner surface of the insert to substantially seal the interface between the insert and the piston.

Abstract: A variable-nozzle assembly comprises a nozzle ring and an array of vanes circumferentially spaced about the nozzle ring and rotatably mounted to the nozzle ring such that the vanes are variable in setting angle, and an insert having a tubular portion and an annular nozzle portion extending generally radially out from one end of the tubular portion. A plurality of axially extending holes extend through a thickness of the nozzle portion. A plurality of spacers have first ends joined to the nozzle ring, opposite second ends of the spacers being engaged in the holes and secured to the nozzle portion by welds formed at the second surface. An annular groove is defined in the second surface of the nozzle portion radially inward of and proximate to the holes. Alternatively or additionally, discrete recesses are formed in the second surface adjacent the holes. The groove and/or recesses facilitate weld penetration.

Abstract: The invention proposes a system for driving a compressor, comprising an induction motor (2) for driving the compressor (3), said induction motor including a squirrel cage rotor, and a controller (1) for controlling the induction motor, said controller comprising a memory for storing drive patterns for driving the induction motor, a first frequency generation means for generating a field frequency based on a field command and/or a second field generation means for generating a voltage frequency based on a voltage command, wherein a drive pattern in extracted from the memory based on the generated frequency or frequencies. Alternatively, the invention proposes a system for driving a compressor, comprising an induction motor (2) for driving the compressor (3), said induction motor including a squirrel cage rotor, and a controller (1) for controlling the induction motor, wherein the controller is adapted to distinguish between a steady state and a transient state of the induction motor.

Abstract: Disclosed are retainers for a turbocharger. In one embodiment, the retainer includes a generally annular body that defines a bore and one or more channels. The bore is generally directed along a central axis of the body and can be configured to mate with a nose of a center housing of a turbocharger. The channels can be configured to accommodate vanes associated with a cartridge assembly of the turbocharger. One or more legs may extend from the retainer body and may be configured to mate with and locate the retainer relative to a cartridge assembly for the turbocharger. The retainer can also include a concave portion disposed around a perimeter of the body. The concave portion and the body may be together configured to act as a spring when the retainer is mechanically loaded in a direction having a component parallel to the central axis. Also disclosed are corresponding turbochargers.