A turbocharger includes a variable nozzle unit, a bearing housing, a circular heat shield plate located between a turbine impeller and the bearing housing, and a water chamber formed in the bearing housing. The heat shield plate is fixed by being pressed against the variable nozzle unit by a disc spring and is radially aligned by being fitted into the bearing housing by a fitting portion. The heat shield plate includes a fitting surface formed in the fitting portion and an inner peripheral heat shield portion projecting radially inward from the fitting surface and located with an axial gap between the inner peripheral heat shield portion and the bearing housing. At least a part of the water chamber exists at the same radial position as a radial position of the fitting portion.

A bi-metal variable geometry turbocharger (VGT) vane includes a structural, airfoil-shaped flag portion, and a functional, cylindrically-shaped shaft portion connected to the flag portion. The flag portion and the shaft portion are formed of a first metal alloy, and the shaft portion further includes a surface area formed of a second metal alloy different from the first metal alloy.

A variable capacity turbocharger includes a housing, a turbine impeller at least partially located in the housing, a scroll flow path located in the housing and encircling the turbine impeller, a first nozzle ring and a second nozzle ring facing each other in the housing, a nozzle flow path located between the first nozzle ring and the second nozzle ring and fluidly coupling the scroll flow path to the turbine impeller, a gap formed between the first nozzle ring and the housing, and a bearing hole located in the first nozzle ring and including an opening adjacent to the gap. The gap is located on an opposite side of the first nozzle ring to the nozzle flow path. Additionally, the gap is connected to the scroll flow path.

Variable geometry turbines having new configurations of vanes are disclosed. New methods for designing new configurations of vanes for geometry turbines having are also disclosed.

A variable nozzle device includes: a nozzle mount; a plurality of nozzle vanes; a drive ring being having a plurality of receiving portions disposed at different positions along a circumferential direction; and a plurality of lever plates each having a fixed portion to be fixed to corresponding one of the plurality of nozzle vanes and an engaging portion to be engaged with corresponding one of the plurality of receiving portions of the drive ring. The receiving portions include a first-side guide surface and a second-side guide surface. The engaging portions each include a first-side roll surface which is to be in contact with the first-side guide surface and a second-side roll surface which is to be in contact with the second-side guide surface. The first-side roll surface includes a lever-plate-side linear portion extending linearly in at least a part of a range which is to be in contact with the first-side guide surface. The first-side guide surface includes a drive-ring-side protruding curved surface portion extending in a protruding curve shape in at least a part of a range which is to be in contact with the first-side roll surface.

A method of assembling a turbocharger having a vaned turbine nozzle includes first forming a sub-assembly of a center housing, shaft, bearings, compressor wheel, turbine wheel, and vane assembly. The vane assembly is held captive in attachment to the center housing by an annular heat shield that includes prongs or the like at its inner and outer peripheries for respectively engaging a first catch formed on the center housing and a second catch formed on the nozzle ring of the vane assembly. The heat shield forms a snap fit to the center housing and nozzle ring, thereby connecting the cartridge to the center housing. The whole sub-assembly is then joined to the turbine housing, in the process axially compressing the heat shield and a spring shroud for exerting an axial biasing force on the nozzle ring.

A turbocharger includes a bearing housing, a variable displacement mechanism, and a restricting member. The variable displacement mechanism includes a nozzle ring and a drive ring. The restricting member includes a flange part, a drive ring guide pin part, and a phase determining pin part. The flange part straddles a first surface of the nozzle ring facing the bearing housing and a second surface of the drive ring facing the bearing housing so that a position thereof with respect to the nozzle ring is fixed. The drive ring guide pin part is formed integrally with the flange part and disposed in a first hole formed on the first surface. The phase determining pin part is formed integrally with the flange part and disposed in a second hole formed on a third surface of the bearing housing facing the variable displacement mechanism.

A method for fabricating a vane for a variable geometry turbocharger (VGT) includes the steps of providing or obtaining a substrate metal in powdered form, mixing a binder with the powdered substrate metal to form a mixture, performing an injection molding process using the mixture to form a green substrate in the shape of the vane, debinding the green substrate to form a brown substrate in the shape of the vane having a porous structure, applying a surface treatment slurry to at least a portion of the brown substrate, and sintering the surface treated brown substrate to form the vane.

An aspect of the present disclosure provides a diagnosis device for an internal combustion engine. The internal combustion engine 1 includes a variable geometry type turbocharger 14, and the turbocharger includes a variable vane 28, a link mechanism configured to operate the variable vane, and an actuator 29 configured to drive the link mechanism. The diagnosis device includes a control unit 100 configured to control an opening degree of the variable vane by controlling the actuator. The control unit determines that an abnormality has occurred in the link mechanism of the turbocharger when an operating time of the internal combustion engine in a predetermined operating region exceeds a predetermined upper limit value and a differential pressure between a target boost pressure determined according to an operating state of the internal combustion engine and an actual boost pressure exceeds a predetermined upper limit value.

A turbine housing assembly can include a turbine housing that defines a rotational axis for a turbine wheel; and a cartridge receivable by the turbine housing, where the cartridge includes a nozzle wall component with an upper nozzle surface and a plate component with a lower nozzle surface, where the upper nozzle surface and the lower nozzle surface define a nozzle space, and vanes positioned in the nozzle space, where the vanes are pivotable between a closed vanes position of 0 percent open and a fully open vanes position of 100 percent open, and where, for a vanes position of at least 50 percent open and less than 75 percent open, an axial dimension of the nozzle space increases with respect to decreasing radius as measured from the rotational axis.