Abstract: A turbocharger includes a variable-nozzle cartridge having a nozzle ring that supports an array of variable vanes in the turbine nozzle. A heat shroud and spring assembly is disposed in a space bounded between the turbine wheel, the nozzle ring, and the center bearing housing of the turbocharger. The heat shroud and spring assembly includes discretely formed heat shroud and spring components configured as annular non-planar disk-shaped parts. The heat shroud and spring are in contact with each other at their radially inner and radially outer peripheral regions, but are spaced apart between those peripheral regions, thereby creating a sealed-off dead space between them. The dead space can significantly reduce the maximum temperature of the spring, relative to arrangements having a single shroud or having dual shrouds with no dead space between them.

Abstract: A turbocharger includes a variable-nozzle cartridge having a nozzle ring that supports an array of variable vanes in the turbine nozzle. A heat shroud and spring assembly is disposed in a space bounded between the turbine wheel, the nozzle ring, and the center bearing housing of the turbocharger. The heat shroud and spring assembly includes discretely formed heat shroud and spring components configured as annular non-planar disk-shaped parts. The heat shroud and spring are in contact with each other at their radially inner and radially outer peripheral regions, but are spaced apart between those peripheral regions, thereby creating a sealed-off dead space between them. The dead space can significantly reduce the maximum temperature of the spring, relative to arrangements having a single shroud or having dual shrouds with no dead space between them.

Abstract: An exhaust gas variable geometry turbine assembly can include a number of pivotable vanes that define throats within an exhaust gas nozzle where each of the pivotable vanes includes a corresponding post, where each of the pivotable vanes is made of a first alloy that includes a first amount of nickel by mass, where each of the corresponding posts is made of a second alloy that includes a second amount of nickel by mass and where the second amount of nickel by mass exceeds the first amount of nickel by mass.

Abstract: A turbocharger having a variable-nozzle turbine formed by pivotable vanes supported by a nozzle ring includes an elastically deformable locator disposed between a radially outwardly facing surface of the center housing and an opposing surface of the nozzle ring. In one embodiment the locator is a metallic ring having a radially undulating waveform shape that repeats a plurality of times about a circumference of the locator. In another embodiment the locator is a metallic ring having a C-shaped cross-section in a radial-axial plane. In still another embodiment the locator is a metallic ring having an S-shaped cross-section in a radial-axial plane. In a further embodiment the locator is a plurality of circumferentially spaced, radial locator pins affixed in the center housing and received in radial slots formed in the nozzle ring, the pins restraining the nozzle ring circumferentially and axially but allowing thermal expansion of the nozzle ring.

Abstract: A turbocharger waste gate valve includes an elastically deformable sealing member formed by sheet metal, the sealing member being carried on one of the poppet valve member and the valve housing and being arranged to be under compression between the valve seat and the valve member end face when the poppet valve member is in the closed position so as to be elastically deformed into a compressed state, and to be released from said compression so as to return to an uncompressed state when the poppet valve member is in the open position. The sealing member in the compressed state contacts the valve seat about a full circumference thereof and contacts the valve member end face about a full circumference thereof so as to substantially seal any gap between the valve member end face and the valve seat.

Abstract: A turbocharger includes a variable-nozzle turbine having a variable vane assembly formed as a cartridge. A pipe-shaped insert of the cartridge fits into an axial bore in the turbine housing. The variable vane assembly includes a nozzle ring to which the variable vanes are mounted. A composite heat shroud is disposed between and axially compressed between the turbocharger's center housing and the nozzle ring. The heat shroud is constructed such that heating of the shroud causes the shroud to deform so as to increase the axial preload exerted by the shroud. In one embodiment the heat shroud is a two-layer structure in which the two layers are formed of different materials having different coefficients of thermal expansion.

Abstract: A turbocharger having a variable-nozzle turbine formed by pivotable vanes supported by a nozzle ring includes an elastically deformable locator disposed between a radially outwardly facing surface of the center housing and an opposing surface of the nozzle ring. In one embodiment the locator is a metallic ring having a radially undulating waveform shape that repeats a plurality of times about a circumference of the locator. In another embodiment the locator is a metallic ring having a C-shaped cross-section in a radial-axial plane. In still another embodiment the locator is a metallic ring having an S-shaped cross-section in a radial-axial plane. In a further embodiment the locator is a plurality of circumferentially spaced, radial locator pins affixed in the center housing and received in radial slots formed in the nozzle ring, the pins restraining the nozzle ring circumferentially and axially but allowing thermal expansion of the nozzle ring.

Abstract: An assembly can include a turbine housing that includes a wastegate passage that extends to a wastegate seat; a wastegate valve that includes a control arm coupled to a wastegate shaft that extends to a wastegate plug; a control linkage operatively coupled to the control arm where the control linkage includes a control axis; an actuator operatively coupled to the control linkage for translation of the control linkage in a direction of the control axis; and a spring operatively coupled at an off-axis angle to the control axis of the control linkage where no load or a partial load is exerted to provide a clearance for centering of the wastegate plug in a closed state and where an increased load is exerted to reduce the clearance in an open state.

Abstract: A turbocharger waste gate valve includes an elastically deformable sealing member formed by sheet metal, the sealing member being carried on one of the poppet valve member and the valve housing and being arranged to be under compression between the valve seat and the valve member end face when the poppet valve member is in the closed position so as to be elastically deformed into a compressed state, and to be released from said compression so as to return to an uncompressed state when the poppet valve member is in the open position. The sealing member in the compressed state contacts the valve seat about a full circumference thereof and contacts the valve member end face about a full circumference thereof so as to substantially seal any gap between the valve member end face and the valve seat.

Abstract: An exhaust gas variable geometry turbine assembly can include a number of pivotable vanes that define throats within an exhaust gas nozzle where each of the pivotable vanes includes a corresponding post, where each of the pivotable vanes is made of a first alloy that includes a first amount of nickel by mass, where each of the corresponding posts is made of a second alloy that includes a second amount of nickel by mass and where the second amount of nickel by mass exceeds the first amount of nickel by mass.

Abstract: An assembly can include a turbine housing that includes a bore, a wastegate seat and a wastegate passage that extends to the wastegate seat; a bushing configured for receipt by the bore; a rotatable wastegate shaft configured for receipt by the bushing; a wastegate plug extending from the wastegate shaft; a control arm operatively coupled to the wastegate shaft; and a biasing cam operatively coupled to the control arm wherein the biasing cam comprises a disengaged orientation associated with a closed position of the wastegate plug with respect to the wastegate seat and an engaged orientation associated with an open position of the wastegate plug with respect to the wastegate seat. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.

Abstract: An assembly can include a turbine housing that includes a wastegate passage that extends to a wastegate seat; a wastegate valve that includes a control arm coupled to a wastegate shaft that extends to a wastegate plug; a control linkage operatively coupled to the control arm where the control linkage includes a control axis; an actuator operatively coupled to the control linkage for translation of the control linkage in a direction of the control axis; and a spring operatively coupled at an off-axis angle to the control axis of the control linkage where no load or a partial load is exerted to provide a clearance for centering of the wastegate plug in a closed state and where an increased load is exerted to reduce the clearance in an open state.

Abstract: An assembly can include a turbine housing that includes a bore, a wastegate seat and a wastegate passage that extends to the wastegate seat; a bushing configured for receipt by the bore; a rotatable wastegate shaft configured for receipt by the bushing; a wastegate plug extending from the wastegate shaft; a control arm operatively coupled to the wastegate shaft; a control linkage operatively coupled to the control arm where the control linkage includes a control axis; an actuator operatively coupled to the control linkage for translation of the control linkage in a direction of the control axis; and a biasing mechanism operatively coupled to the control linkage where the biasing mechanism applies an off-axis force to the control linkage. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.

Abstract: An assembly for a turbocharger can include a turbine housing that defines an exhaust inflow chamber that includes a wastegate valve seat and that defines an exhaust outflow chamber; and a wastegate valve plug that includes a seal surface where, in a closed state, the seal surface seats against the wastegate valve seat and where, in an open state, the wastegate valve plug extends into the exhaust inflow chamber. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.

Abstract: An assembly can include a turbine housing that includes a bore, a wastegate seat and a wastegate passage that extends to the wastegate seat; a bushing configured for receipt by the bore; a rotatable wastegate shaft configured for receipt by the bushing; a wastegate plug extending from the wastegate shaft; a control arm operatively coupled to the wastegate shaft; and a biasing cam operatively coupled to the control arm wherein the biasing cam comprises a disengaged orientation associated with a closed position of the wastegate plug with respect to the wastegate seat and an engaged orientation associated with an open position of the wastegate plug with respect to the wastegate seat. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.

Abstract: An assembly can include a turbine housing that includes a bore, a wastegate seat and a wastegate passage that extends to the wastegate seat; a bushing configured for receipt by the bore; a rotatable wastegate shaft configured for receipt by the bushing; a wastegate plug extending from the wastegate shaft; a control arm operatively coupled to the wastegate shaft; a control linkage operatively coupled to the control arm where the control linkage includes a control axis; an actuator operatively coupled to the control linkage for translation of the control linkage in a direction of the control axis; and a biasing mechanism operatively coupled to the control linkage where the biasing mechanism applies an off-axis force to the control linkage. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.

Abstract: An assembly for a turbocharger can include a turbine housing that defines an exhaust inflow chamber that includes a wastegate valve seat and that defines an exhaust outflow chamber; and a wastegate valve plug that includes a seal surface where, in a closed state, the seal surface seats against the wastegate valve seat and where, in an open state, the wastegate valve plug extends into the exhaust inflow chamber. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.