Abstract: A nozzle vane of a variable geometry turbocharger comprises: a nozzle vane body rotatably disposed in an exhaust gas passage defined between a shroud surface and a hub surface; and a fin disposed on at least one of a pressure surface or a suction surface of the nozzle vane body and disposed within a range of 0.6L from a trailing edge of the nozzle vane body, where L refers to a chord length of the nozzle vane body. The fin satisfies a relationship of 0.3L?X, where X refers to a length of the fin along a chord direction of the nozzle vane body.

Abstract: A turbocharger (10A) has a back plate (41). The back plate (41) is provided with a plate section (41a) and a flange section (41c) which is formed radially outside the plate section (41a) and which is supported so as to be sandwiched between a bearing housing (16) and a turbine housing (31). The turbocharger (10A) is further provided with a flange heat shielding section (53) provided between the flange section (41c) and the bearing housing (16) and consisting of a material having lower heat conductivity than the turbine housing (31) and the back plate (41).

Abstract: A turbine includes: a turbine impeller; a housing disposed so as to enclose the turbine impeller, and including a scroll passage positioned on an outer circumferential side of the turbine impeller and an inner circumferential wall part defining an inner circumferential boundary of the scroll passage; a plurality of nozzle vanes disposed inside an intermediate flow passage which is positioned, in an exhaust gas flow direction, on a downstream side of the scroll passage and on an upstream side of the turbine impeller; and a plate disposed on a side of the intermediate flow passage with respect to the inner circumferential wall part so as to face the intermediate flow passage such that a gap is formed between the plate and the inner circumferential wall part in an axial direction. The plate has at least one through hole through which the intermediate flow passage and the gap are communicated with each other.

Abstract: There is provided a turbine wheel includes a plurality of long blades and a plurality of short blades. A trailing edge of each short blade is positioned upstream of a trailing edge of each long blade in an axial direction of the turbine wheel, and at least one of a leading edge of each long blade or a leading edge of each short blade includes an inclined part which is inclined so that a distance to a rotational axis of the turbine wheel decreases toward a hub.

Abstract: A turbine for a turbocharger includes: a turbine impeller coupled to a compressor impeller via a rotational shaft; a turbine casing disposed so as to cover the turbine impeller, the turbine casing including a scroll flow passage and a scroll outlet portion disposed on an inner side, in a radial direction, of the scroll flow passage, for guiding exhaust gas from the scroll flow passage to the turbine impeller; and a back-surface side member disposed so as to face a back surface of the turbine impeller. The back-surface side member includes a protruding portion disposed on an impeller facing surface which faces the back surface of the turbine impeller, the protruding portion protruding toward the back surface and extending in a circumferential direction.

Abstract: Provided is a casing 21 for an exhaust turbocharger turbine 2, configured so as to house a turbine rotor 23 to be driven by exhaust gas and form a spiral scroll 22 serving as a path for supplying the exhaust gas to the turbine rotor 23, wherein the scroll 22 includes a first region 222a extending from a spiral origin position 222s to a predetermined angle ? and a second region 222b extending from the predetermined angle ? to a spiral end position 222e, with the surface area of an interior wall thereof decreasing from the spiral origin position 222s toward the spiral end position 222e, and the interior wall at the first region 222a has a lower surface roughness than that at the second region 222b.

Abstract: A turbine includes: a turbine impeller; a housing disposed so as to enclose the turbine impeller and including a scroll passage positioned on an outer circumferential side of the turbine impeller; a nozzle vane disposed inside an intermediate flow passage which is positioned, in an exhaust gas flow direction, on a downstream side of the scroll passage and on an upstream side of the turbine impeller; a plate disposed on a side of the intermediate flow passage with respect to an inner circumferential wall part of the housing, defining an inner circumferential boundary of the scroll passage, so as to face the intermediate flow passage such that a gap is formed between the plate and the inner circumferential wall part in an axial direction; and at least one guide vane disposed in the gap between the inner circumferential wall part and the plate in the axial direction.

Abstract: A turbine includes a turbine impeller, a turbine housing disposed so as to cover the turbine impeller and internally forming a scroll flow passage through which an exhaust gas flows, and a throat forming portion which is provided as a separate piece from the turbine housing. The throat forming portion is disposed to face a section of the turbine housing and forms a hub-side wall surface of a throat portion of the scroll flow passage in an axial direction, the section forming a shroud-side wall surface of the throat portion.

Abstract: A variable geometry turbocharger (100) includes a bearing housing (10) including a bearing-housing side support portion (40) configured to support a radially outer portion (38) of a nozzle mount (16) from a side opposite to a scroll flow passage (4) in an axial direction of a turbine rotor (2), and wherein at least one of the following condition (a) or (b) is satisfied: (a) the bearing-housing side support portion (40) includes at least one bearing-housing side recess portion (46) formed so as to be recessed in the axial direction so as not to be in contact with the radially outer portion (38); (b) the radially outer portion (38) of the nozzle mount (16) includes at least one nozzle-mount side recess portion (62) formed so as to be recessed in the axial direction so as not to be in contact with the bearing-housing side support portion (40).

Abstract: A radial inflow turbine includes a scroll flow passage, a turbine wheel disposed radially inward of the scroll flow passage, a plurality of variable nozzle vanes disposed on a flow passage extending from the scroll flow passage toward the turbine wheel, at a radial position between the scroll flow passage and the turbine wheel, a nozzle mount rotatably supporting each of the plurality of variable nozzle vanes, a nozzle plate arranged to face the nozzle mount and forming the flow passage with the nozzle mount, and a swirl generating member disposed, radially outward of the plurality of variable nozzle vanes, on the nozzle plate in a height range which is smaller than that of a vane height of each of the plurality of variable nozzle vanes. A position of an end part of the swirl generating member on a side of the nozzle mount is farther away from the nozzle mount than a position of an end part of each of the plurality of variable nozzle vanes on the side of the nozzle mount in an axial direction.

Abstract: A nozzle vane for a variable geometry turbocharger has an airfoil including a leading edge, a trailing edge, a pressure surface, and a suction surface at least in a center position in a blade height direction. The airfoil satisfies 0?Wmax/L<0.03, where Wmax is a maximum value of a distance from a line segment connecting the trailing edge and a fixed point on the pressure surface at a 40% chord position from the trailing edge toward the leading edge to a given point on the pressure surface between the trailing edge and the fixed point, and L is a length of the line segment.

Abstract: A variable geometry turbocharger (100) includes a bearing housing (10) including a bearing-housing side support portion (40) configured to support a radially outer portion (38) of a nozzle mount (16) from a side opposite to a scroll flow passage (4) in an axial direction of a turbine rotor (2), and wherein at least one of the following condition (a) or (b) is satisfied: (a) the bearing-housing side support portion (40) includes at least one bearing-housing side recess portion (46) formed so as to be recessed in the axial direction so as not to be in contact with the radially outer portion (38); (b) the radially outer portion (38) of the nozzle mount (16) includes at least one nozzle-mount side recess portion (62) formed so as to be recessed in the axial direction so as not to be in contact with the bearing-housing side support portion (40).

Abstract: A turbine includes: a turbine impeller; a housing disposed so as to enclose the turbine impeller, and including a scroll passage positioned on an outer circumferential side of the turbine impeller and an inner circumferential wall part defining an inner circumferential boundary of the scroll passage; a plurality of nozzle vanes disposed inside an intermediate flow passage which is positioned, in an exhaust gas flow direction, on a downstream side of the scroll passage and on an upstream side of the turbine impeller; and a plate disposed on a side of the intermediate flow passage with respect to the inner circumferential wall part so as to face the intermediate flow passage such that a gap is formed between the plate and the inner circumferential wall part in an axial direction. The plate has at least one through hole through which the intermediate flow passage and the gap are communicated with each other.

Abstract: A nozzle vane for a variable geometry turbocharger satisfies 0.45<(Xp/L)<0.60, where L is a chord length of the nozzle vane, and Xp is a distance between a leading edge of the nozzle vane and a rotation center of the nozzle vane.

Abstract: A variable nozzle mechanism in which a nozzle mount has a first surface which has a minimum clearance in a direction of an axis with respect to a lever side facing surface in an opposing region facing the lever side facing surface in the direction of the axis, and a second surface which is disposed adjacent to the first surface in a circumferential direction of the nozzle mount and has a clearance in the direction of the axis with respect to the lever side facing surface larger than the clearance in the direction of the axis between the first surface and the lever side facing surface.

Abstract: A turbine rotor blade according to at least one embodiment of the present invention is to be connected to a rotational shaft so as to be rotatable around an axis and includes: a hub having a hub surface inclined with respect to the axis in a cross-section along the axis; at least one rotor blade disposed on the hub surface; and a connection passage disposed inside the turbine rotor blade and connecting a first opening disposed in the at least one rotor blade and a second opening disposed downstream of the first opening in the turbine rotor blade.

Abstract: A turbine includes a turbine impeller, a turbine housing disposed so as to cover the turbine impeller and internally forming a scroll flow passage through which an exhaust gas flows, and a throat forming portion which is provided as a separate piece from the turbine housing. The throat forming portion is disposed to face a section of the turbine housing and forms a hub-side wall surface of a throat portion of the scroll flow passage in an axial direction, the section forming a shroud-side wall surface of the throat portion.

Abstract: A turbocharge includes: a compressor wheel; a turbine wheel configured to rotate with the compressor wheel; a turbine housing disposed so as to cover the turbine wheel; a bearing supporting a rotational shaft of the turbine wheel rotatably; and a bearing housing accommodating the bearing. One of the turbine housing or the bearing housing includes a fin portion protruding toward the other one of the turbine housing or the bearing housing so as to extend along an axial direction of the rotational shaft, and, between the turbine housing and the bearing housing, a cavity is formed on each side of the fin portion with respect to a radial direction of the rotational shaft.

Abstract: A turbine housing includes: a housing body which includes a turbine housing part housing a turbine wheel, an inlet section forming an inlet flow passage for guiding exhaust gas to the turbine housing part, an outlet section forming an outlet flow passage for discharging the exhaust gas from the turbine housing part, and a waste-gate flow passage which brings the inlet flow passage and the outlet flow passage into communication so as to bypass the turbine housing part; and a sleeve disposed along an inner wall surface of the housing body forming the waste gate flow passage, at least on a downstream side of the waste-gate flow passage of the housing body with respect to a flow direction of the exhaust gas.

Abstract: A turbine housing includes: a housing body which is configured to accommodate a turbine wheel and which includes an inlet section forming an inlet flow passage for guiding exhaust gas to the turbine wheel, and an outlet section forming an outlet flow passage for discharging the exhaust gas from the turbine wheel; and at least one sleeve disposed along an inner wall surface of at least one of the inlet section or the outlet section of the housing body. The at least one sleeve includes a plurality of sections divided along a flow direction of the exhaust gas.