Abstract: A control method for use in an engine braking maneuver for an internal combustion engine (ICE) system including a turbocharger having a variable-nozzle turbine (VNT), the ICE system further including an exhaust flap disposed in an exhaust line downstream of the variable-nozzle turbine. Prior to closing the exhaust flap, the VNT vanes are first parked in a fully open position. After the exhaust flap closes, the vanes are pivoted to a fully closed position and are continuously urged against a hard stop as long as the exhaust flap is closed. Termination of engine braking entails pivoting the vanes back to the fully open position, whereupon the exhaust flap is opened.

Abstract: A variable-nozzle turbocharger includes a variable-vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes connected to vane arms whose distal ends engage recesses in the radially inner periphery of a rotatable unison ring. Rotation of the unison ring causes the vane arms to pivot about their respective pivot axes at the proximal ends of the arms. The vanes are locked in their fully open position by a locking arrangement that includes locking tongues that extend radially inwardly from the inner periphery of the unison ring and contact the vane arms intermediate their distal and proximal ends.

Abstract: A turbine assembly can include a turbine wheel, a shroud component, a turbine housing and a seal that includes a wall and a lower lip that that extends radially outwardly from the wall where the seal is disposed, at least in part, between an outer surface of the shroud component and an inner surface of the turbine housing and where the lower lip is in contact with the turbine housing.

Abstract: A variable-nozzle turbocharger includes a variable vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes, an insert having a tubular portion sealingly received into a bore of the turbine housing and having a nozzle portion extending radially out from one end of the tubular portion and being axially spaced from the nozzle ring with the vanes therebetween, and a plurality of two-piece self-centering spacer assemblies connected between the nozzle portion of the insert and the nozzle ring. Each spacer assembly comprises a tubular sleeve and a separate pin that passes through the through-passage of the sleeve, end portions of the pin being secured respectively to the nozzle ring and the nozzle portion. One end of each sleeve has a conical surface and engages in a corresponding conical countersink in the adjacent face of the nozzle ring or nozzle portion.

Abstract: A turbocharger includes a variable turbine nozzle defined between a nozzle ring and a pipe flange, and having a plurality of circumferentially spaced vanes rotatably mounted on the nozzle ring such that the vanes are pivotable. Each vane includes an airfoil section and a disk section rigidly affixed to an end of the airfoil section, the disk section being disposed against a face of the pipe flange, each disk section having a plurality of perforations extending axially therethrough. The pipe flange has a corresponding number of holes for each disk section of the vanes, the holes being positioned such that as each vane is rotated the perforations in the disk sections and the holes in the pipe flange of the insert become aligned in some positions of the vanes, allowing exhaust gas to pass between the nozzle and a space on an opposite side of the pipe flange from the nozzle.

Abstract: A turbocharger has an annular bypass valve disposed in an annular portion of a bypass passage of the turbine housing. The turbine housing defines an exhaust gas chamber having separate half-annular first and second scrolls, and a portion of the bypass passage is sector-divided by a pair of dividing walls that create two 180-degree bypass sectors respectively connected to the first and second scrolls. Each dividing wall has a through-hole. The valve rotor defines a pair of valve members that close the through-holes when the bypass valve is fully closed. When the valve rotor begins to rotate toward an open position, first the valve members open the through-holes to connect the two bypass sectors, and then the bypass flow passages begin to open.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry conical mechanism comprising a plurality of vanes that in the closed position collectively form a frusto-conical inlet member having a trailing edge inner diameter that is smaller than an inner diameter of the shroud surface of the compressor housing at the inducer portion of the compressor wheel such that an effective diameter of the air inlet at the inducer portion is determined by the trailing edge inner diameter of the variable-geometry conical mechanism. The vanes in the open position are pivoted radially outwardly so as to increase the trailing edge inner diameter of the inlet member and thereby increase the effective diameter of the air inlet at the inducer portion.

Abstract: A turbocharger has an annular bypass valve disposed in an annular portion of a bypass passage of the turbine housing. The turbine housing defines an exhaust gas chamber having separate half-annular first and second scrolls, and a portion of the bypass passage is sector-divided by a pair of dividing walls that create two 180-degree bypass sectors respectively connected to the first and second scrolls. Each dividing wall has a through-hole. The valve rotor defines a pair of valve members that close the through-holes when the bypass valve is fully closed. When the valve rotor begins to rotate toward an open position, first the valve members open the through-holes to connect the two bypass sectors, and then the bypass flow passages begin to open.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry orifice actuated by a rotatable actuator ring. In the closed position, the orifice's inner diameter is smaller than that of a shroud surface of the compressor housing and therefore dictates the effective inlet diameter for the compressor. In the open position the orifice no longer forms an inner diameter smaller than the shroud surface, so that the effective inlet diameter is determined by the shroud surface.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry conduit comprising a plurality of vanes that in the closed position collectively form a converging inlet member having a trailing edge inner diameter that is smaller than an inner diameter of the shroud surface of the compressor housing at the inducer portion of the compressor wheel such that an effective diameter of the air inlet at the inducer portion is determined by the trailing edge inner diameter of the variable-geometry conduit. The vanes in the open position are pivoted radially outwardly so as to increase the trailing edge inner diameter of the inlet member and thereby increase the effective diameter of the air inlet at the inducer portion.

Abstract: A turbine assembly can include a turbine wheel, a shroud component, a turbine housing and a seal that includes a wall and a lower lip that that extends radially outwardly from the wall where the seal is disposed, at least in part, between an outer surface of the shroud component and an inner surface of the turbine housing and where the lower lip is in contact with the turbine housing.

Abstract: A turbocharger includes a variable turbine nozzle defined between a nozzle ring and a pipe flange, and having a plurality of circumferentially spaced vanes rotatably mounted on the nozzle ring such that the vanes are pivotable. Each vane includes an airfoil section and a disk section rigidly affixed to an end of the airfoil section, the disk section being disposed against a face of the pipe flange, each disk section having a plurality of perforations extending axially therethrough. The pipe flange has a corresponding number of holes for each disk section of the vanes, the holes being positioned such that as each vane is rotated the perforations in the disk sections and the holes in the pipe flange of the insert become aligned in some positions of the vanes, allowing exhaust gas to pass between the nozzle and a space on an opposite side of the pipe flange from the nozzle.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry conduit comprising a plurality of vanes that in the closed position collectively form a converging inlet member having a trailing edge inner diameter that is smaller than an inner diameter of the shroud surface of the compressor housing at the inducer portion of the compressor wheel such that an effective diameter of the air inlet at the inducer portion is determined by the trailing edge inner diameter of the variable-geometry conduit. The vanes in the open position are pivoted radially outwardly so as to increase the trailing edge inner diameter of the inlet member and thereby increase the effective diameter of the air inlet at the inducer portion.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry orifice actuated by a rotatable actuator ring. In the closed position, the orifice's inner diameter is smaller than that of a shroud surface of the compressor housing and therefore dictates the effective inlet diameter for the compressor. In the open position the orifice no longer forms an inner diameter smaller than the shroud surface, so that the effective inlet diameter is determined by the shroud surface.

Abstract: A turbine assembly can include a turbine wheel, a shroud component, a turbine housing and a seal that includes a wall and a lower lip that that extends radially outwardly from the wall at an obtuse angle where the seal is disposed, at least in part, between an outer surface of the shroud component and an inner surface of the turbine housing. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.

Abstract: A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a variable-geometry conical mechanism comprising a plurality of vanes that in the closed position collectively form a frusto-conical inlet member having a trailing edge inner diameter that is smaller than an inner diameter of the shroud surface of the compressor housing at the inducer portion of the compressor wheel such that an effective diameter of the air inlet at the inducer portion is determined by the trailing edge inner diameter of the variable-geometry conical mechanism. The vanes in the open position are pivoted radially outwardly so as to increase the trailing edge inner diameter of the inlet member and thereby increase the effective diameter of the air inlet at the inducer portion.

Abstract: A variable-nozzle turbocharger includes a variable vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes, an insert having a tubular portion sealingly received into a bore of the turbine housing and having a nozzle portion extending radially out from one end of the tubular portion and being axially spaced from the nozzle ring with the vanes therebetween, and a plurality of two-piece self-centering spacer assemblies connected between the nozzle portion of the insert and the nozzle ring. Each spacer assembly comprises a tubular sleeve and a separate pin that passes through the through-passage of the sleeve, end portions of the pin being secured respectively to the nozzle ring and the nozzle portion. One end of each sleeve has a conical surface and engages in a corresponding conical countersink in the adjacent face of the nozzle ring or nozzle portion.

Abstract: A turbine assembly can include a turbine wheel, a shroud component, a turbine housing and a seal that includes a wall and a lower lip that that extends radially outwardly from the wall at an obtuse angle where the seal is disposed, at least in part, between an outer surface of the shroud component and an inner surface of the turbine housing. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.