Abstract: A variable turbine geometry assembly includes an adjustment ring extending along and rotatable about an axis, at least one vane lever coupled to the adjustment ring, and at least one vane coupled to the at least one vane lever. The variable turbine geometry assembly also includes a biasing member coupled to the adjustment ring at a first circumferential location on the adjustment ring and coupled to the adjustment ring at a second circumferential location on the adjustment ring. The biasing member extends from the first circumferential location to the second circumferential location. The biasing member is operably in contact with the at least one vane lever between the first circumferential location and the second circumferential location to bias the at least one vane lever toward the adjustment ring and to reduce vibration between the adjustment ring and the at least one vane lever.

Abstract: A turbocharger includes a turbine wheel rotatable about an axis and a turbine housing disposed about the turbine wheel. The turbine housing has an inlet portion defining a turbine housing inlet and has a volute portion defining a turbine housing interior. The volute portion has a first volute wall, a second volute wall spaced from the first volute wall, and a tongue separating the turbine housing inlet and the turbine housing interior. The tongue has a first tongue portion extending from the first volute wall substantially toward the second volute wall along the axis, a second tongue portion extending from the first tongue portion substantially circumferentially about the axis, and a third tongue portion extending from the second tongue portion substantially toward the second volute wall along the axis to reduce high cycle fatigue of the turbine wheel.

Abstract: A turbocharger includes a turbine wheel rotatable about an axis and a turbine housing disposed about the turbine wheel. The turbine housing has an inlet portion defining a turbine housing inlet and has a volute portion defining a turbine housing interior. The volute portion has a first volute wall, a second volute wall spaced from the first volute wall, and a tongue separating the turbine housing inlet and the turbine housing interior. The tongue has a first tongue portion extending from the first volute wall substantially toward the second volute wall along the axis, a second tongue portion extending from the first tongue portion substantially circumferentially about the axis, and a third tongue portion extending from the second tongue portion substantially toward the second volute wall along the axis to reduce high cycle fatigue of the turbine wheel.

Abstract: A turbine diffuser configured for use in a turbocharger is disclosed. The turbine diffuser may comprise a diffuser wall defining the diffuser and circumscribing a central axis of the diffuser, and a plurality of deswirl ribs each extending axially along the diffuser wall. Each of the deswirl ribs may have a first end attached to the diffuser wall, and an opposing second end exposed in an interior space of the diffuser. The deswirl ribs may be configured to reduce rotation of exhaust gas that flows through the diffuser.

Abstract: A turbine wheel includes a hub, a plurality of blades extending from the hub, and a backwall extending from the hub and having an outer diameter. The backwall includes a first backwall surface and an opposing second backwall surface. The first backwall surface includes a datum ring having a diameter between approximately 50% and approximately 85% of the outer diameter.