Abstract: A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Abstract: A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Abstract: A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Abstract: A variable geometry turbine comprises: a turbine wheel in a housing for rotation about a turbine axis; an annular inlet passage defined between respective radial inlet surfaces of first and second wall members, at least one of said first and second wall members being moveable along the turbine axis to vary the size of the inlet passage; an array of vanes extending across the inlet passage, said vanes being connected to said first wall member; a complementary array of vane slots defined by the second wall member, said vane slots configured to receive said vanes to accommodate relative movement between the first and second wall members; the second wall member comprising at least two axially adjacent co-axial plates, a first plate defining a first array of openings which overlie a second array of openings defined by a second plate so as to define said array of vane slots, said first plate being fixed to said second plate.

Abstract: A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Abstract: A compressor wheel for a turbocharger comprising a central hub and a plurality of impeller blades extending outwardly from the hub. Each of the blades defines a leading edge, a trailing edge and a root portion which connects the blade to the hub. At least one of the blades has a surface provided with a variable thickness surface layer of a ceramic material. The leading edge of the blade is provided with a thicker surface layer of the ceramic material than the trailing edge of the blade, the root portion of the blade, or both the trailing edge and root portion of the blade.

Abstract: A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Abstract: A variable geometry turbine comprises: a turbine wheel in a housing for rotation about a turbine axis; an annular inlet passage defined between respective radial inlet surfaces of first and second wall members, at least one of said first and second wall members being moveable along the turbine axis to vary the size of the inlet passage; an array of vanes extending across the inlet passage, said vanes being connected to said first wall member; a complementary array of vane slots defined by the second wall member, said vane slots configured to receive said vanes to accommodate relative movement between the first and second wall members; the second wall member comprising at least two axially adjacent co-axial plates, a first plate defining a first array of openings which overlie a second array of openings defined by a second plate so as to define said array of vane slots, said first plate being fixed to said second plate.

Abstract: A variable geometry turbine comprises: a turbine wheel (5) in a housing (1) for rotation about a turbine axis, an annular inlet passage (9) defined between respective radial inlet surfaces of first and second wall members (11, 12), at least one of said first and second wall members being moveable along the turbine axis to vary the size of the inlet passage; an array of vanes (14) extending across the inlet passage, said vanes being connected to said first wall member; a complementary array of vane slots (28) defined by the second wall member, said vane slots configured to receive said vanes to accommodate relative movement between the first and second wall members; the second wall member comprising at least two axially adjacent co-axial plates (29, 30), a first plate (29) defining a first array of openings which overlie a second array of openings defined by a second plate (30) so as to define said array of vane slots, said first plate being fixed to said second plate.

Abstract: A variable geometry turbine comprising: a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls; a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; the annular inlet divided into axially adjacent annular portions by at least one annular baffle which is axially spaced from the first and second inlet sidewalls; inlet formations extending axially across at least two of said annular portions defined by the or each baffle so as to divide said annular inlet into at least two axially offset inlet passages; the baffle(s) and inlet formations forming part of a nozzle assembly located within said annular inlet; wherein first and second components of the nozzle assembly define complementary features which co-operate to connect together said first and second components.

Abstract: A variable geometry turbine comprises: a turbine wheel in a housing for rotation about a turbine axis; an annular inlet passage defined between respective radial inlet surfaces of first and second wall members, at least one of said first and second wall members being moveable along the turbine axis to vary the size of the inlet passage; an array of vanes extending across the inlet passage, said vanes being connected to said first wall member; a complementary array of vane slots defined by the second wall member, said vane slots configured to receive said vanes to accommodate relative movement between the first and second wall members; the second wall member comprising at least two axially adjacent co-axial plates, a first plate defining a first array of openings which overlie a second array of openings defined by a second plate so as to define said array of vane slots, said first plate being fixed to said second plate.

Abstract: A variable geometry turbine comprises a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls; and a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; wherein the annular inlet is divided into at least three axially offset annular inlet portions by two or more axially spaced annular baffles disposed between the first and second inlet sidewalls; inlet vanes extending axially into at least one of the inlet portions and defining circumferentially adjacent inlet passages; and wherein each of at least two of said baffles extends radially inboard of inlet vanes which extend into at least one of the inlet portions axially adjacent the respective baffle, and wherein a distance between an inner diameter of a first baffle of said at least two of said baffles and a trailing edge of a radially innermost vane in one of

Abstract: According to a first aspect of the present invention there is provided a variable geometry turbine comprising: a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls, the annular inlet being divided into at least two axially offset inlet portions; a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; and a guide for guiding the movement of the cylindrical sleeve, the guide being at least partially located within the inlet at a radially extent of the inlet portions, and extending in an axial direction parallel to the turbine axis.

Abstract: According to a first aspect of the present invention there is provided a variable geometry turbine comprising: a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls, the annular inlet being divided into at least two axially offset inlet portions; a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; and a guide for guiding the movement of the cylindrical sleeve, the guide being at least partially located within the inlet at a radially extent of the inlet portions, and extending in an axial direction parallel to the turbine axis.

Abstract: A variable geometry turbine comprising a turbine wheel mounted for rotation about a turbine axis within a housing. The housing defines an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls. The turbine further comprises a cylindrical sleeve that is axially movable across the annular inlet to vary the size of a gas flow path through the inlet. The annular inlet is divided into at least two axially offset inlet passages. The inner diameter of the sleeve is greater than the inner diameter of the inlet passages.

Abstract: A compressor wheel for a turbocharger comprising a central hub and a plurality of impeller blades extending outwardly from the hub. Each of the blades defines a leading edge, a trailing edge and a root portion which connects the blade to the hub. At least one of the blades has a surface provided with a variable thickness surface layer of a ceramic material. The leading edge of the blade is provided with a thicker surface layer of the ceramic material than the trailing edge of the blade, the root portion of the blade, or both the trailing edge and root portion of the blade.

Abstract: According to a first aspect of the present invention there is provided a variable geometry turbine comprising: a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls, the annular inlet being divided into at least two axially offset inlet portions; a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; and a guide for guiding the movement of the cylindrical sleeve, the guide being at least partially located within the inlet at a radially extent of the inlet portions, and extending in an axial direction parallel to the turbine axis.

Abstract: A variable geometry turbine comprises: a turbine wheel (5) in a housing (1) for rotation about a turbine axis, —an annular inlet passage (9) defined between respective radial inlet surfaces of first and second wall members (11, 12), at least one of said first and second wall members being moveable along the turbine axis to vary the size of the inlet passage; an array of vanes (14) extending across the inlet passage, said vanes being connected to said first wall member; a complementary array of vane slots (28) defined by the second wall member, said vane slots configured to receive said vanes to accommodate relative movement between the first and second wall members; the second wall member comprising at least two axially adjacent co-axial plates (29, 30), a first plate (29) defining a first array of openings which overlie a second array of openings defined by a second plate (30) so as to define said array of vane slots, said first plate being fixed to said second plate.

Abstract: A variable geometry turbine comprises a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls; and a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; wherein the annular inlet is divided into at least three axially offset annular inlet portions by two or more axially spaced annular baffles disposed between the first and second inlet sidewalls; inlet vanes extending axially into at least one of the inlet portions and defining circumferentially adjacent inlet passages; and wherein each of at least two of said baffles extends radially inboard of inlet vanes which extend into at least one of the inlet portions axially adjacent the respective baffle, and wherein a distance between an inner diameter of a first baffle of said at least two of said baffles and a trailing edge of a radially innermost vane in one of

Abstract: A variable geometry turbine comprising: a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls; a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the inlet; the annular inlet divided into axially adjacent annular portions by at least one annular baffle which is axially spaced from the first and second inlet sidewalls; inlet formations extending axially across at least two of said annular portions defined by the or each baffle so as to divide said annular inlet into at least two axially offset inlet passages; the baffle(s) and inlet formations forming part of a nozzle assembly located within said annular inlet; wherein first and second components of the nozzle assembly define complementary features which co-operate to connect together said first and second components.