A turbine housing for a turbocharger of an internal combustion engine includes an annular duct for conducting an exhaust-gas mass flow to a turbine wheel to be disposed in the turbine housing and an exhaust-gas discharge duct for discharging the exhaust-gas mass flow from the turbine housing after impinging on the turbine wheel. An insulating element is respectively disposed in a region of an inner wall of the annular duct and in a region of an inner wall of the exhaust-gas discharge duct. A turbocharger having the turbine housing is also provided.

A turbocharger includes a turbine housing formed with openings of twin scrolls such that the openings are arranged to be adjacent to each other in an axial direction of a turbine. A fixed sleeve is fixedly disposed within the turbine housing such that an inner surface of the fixed sleeve defines a basic passage as a passage for exhaust gas emerging from the turbine while defining a bypass passage outside the basic passage as a passage for exhaust gas bypassing the turbine. A sliding ring can slide in the axial direction of the turbine between the fixed sleeve and the turbine housing, to control a state in which exhaust gas passing through the twin scrolls is supplied to the turbine and a state in which the exhaust gas passing through the twin scrolls is discharged into the bypass passage while bypassing the turbine.

A compressor wheel includes a compressor wheel body, and a thermal insulating coating layer disposed so as to cover at least a part of a back surface of the compressor wheel body.

A turbocharger includes ball bearings each including an inner ring and an inner ring mounted to a shaft, and an outer ring and an outer ring provided so as to be relatively rotatable in a bearing hole, and damper portions formed in at least one of outer peripheral surfaces of the outer ring and the outer ring and opposed surfaces of inner peripheral surface of the bearing hole opposed to the outer peripheral surfaces of the outer ring and the outer ring.

A turbine comprises a housing defining a turbine chamber with a turbine wheel supported for rotation about an axis. The housing further defines first and second inlet volutes which each spiral radially inwards and extend from a respective inlet to adjoin the turbine chamber and a volute tongue for each inlet volute. The tongue of the first volute radially separating a downstream portion of the first volute adjacent the chamber from an upstream portion of the first volute adjacent said inlet of the first volute, and the tongue of the second volute radially separating a downstream portion of the second volute adjacent the chamber from an upstream portion of the second volute adjacent said inlet of the second volute. The tongues having a turbine scroll tongue overlap which is substantially zero or positive; and the first volute tongue is angularly spaced about the axis from the second volute tongue.

Systems are provided for a crankcase ventilation duct. In one example, the crankcase ventilation duct is integrally formed with a compressor housing wherein surfaces of the compressor housing shape a passage of the crankcase ventilation duct.

An internal combustion engine is equipped with a turbocharger that includes: a centrifugal compressor impeller; an axial flow turbine wheel coupled to the compressor impeller via a rotational shaft; a bearing that supports the rotational shaft; and a housing that houses at least the compressor impeller and the bearing among the compressor impeller, the bearing and the turbine wheel. The turbine wheel is coupled to the rotational shaft such that an outlet of turbine blades of the turbine wheel is located on the side of the compressor impeller. The compressor impeller is arranged such that an inlet of the compressor impeller becomes closer to the turbine wheel than an outlet of the compressor impeller.

A centrifugal compressor operable in a wide operation range under a condition accompanied with pulsations of a pressure and a flow rate. The centrifugal compressor has a casing including at least one recirculation channel that includes a first inlet slit connected to an air flow passage on a downstream side of a leading edge in an air flow direction of the air flow passage, a second inlet slit connected to the air flow passage on a downstream side of the first inlet slit in the air flow direction of the air flow passage, a first vane disposed on a downstream side of the first inlet slit or in the first inlet slit in the at least one recirculation channel, and a second vane disposed on a downstream side of the second inlet slit or in the second inlet slit in the at least one recirculation channel.

A centrifugal compressor includes a rotation shaft, a compressor impeller attached to one end of the rotation shaft, and a first wall surface and a second wall surface formed inside a housing so as to face each other in an axial direction. A diffuser is formed between the first wall surface and the second wall surface in the axial direction, and a wall portion separates the diffuser from an axial space inside the housing in which the rotation shaft extends. The wall portion includes at least one extraction hole that fluidly couples the diffuser to the axial spate and that is configured to extract a gas from the diffuser.

A turbocharger device includes an annular spring element for axially clamping a guide device of a variable turbine geometry against a turbine housing. The annular spring element rests radially outwardly on the bearing housing and radially inwardly on a component of the guide device. The spring element has an annular radial outer flange in contact with the bearing housing, and a plurality of tabs which extend from the outer flange radially inwardly in the direction of the guide device and come into contact with a component thereof. An annular spring element for such a turbocharger is also provided.