A turbocharger is provided with an improved bearing which is formed as a floating ring bearing or a semi-floating ring bearing having a conical or hemispherical shape which supports both journal and thrust loads. The floating ring bearing may have conical floating ring bearings (70), (100), (180) that define inner and outer conical bearing surfaces (71), (108), (185) and (72), (109), (186) which cooperate on the inside with corresponding conical journals (75/76), (111/112), (187/188) that rotate with the shaft (53), and cooperate on the outside with a stationary bearing housing (52) to form inner and outer fluid films. Alternatively, the floating ring bearing may have a pair of hemispherical floating ring bearings (85), (140), (210) that have hemispherical inner and outer bearing surfaces (86), (144), (211) and (87), (145), (212) which form inner and outer fluid films. A semi-floating ring bearing may also be provided with these structures.

A turbocharger includes a turbine housing, an annular metal plate, and a scroll passage defining plate. The metal plate defines a connecting passage in the turbine housing. The connecting passage connects a turbine chamber and a turbine scroll passage to each other. The scroll passage defining plate includes a passage defining portion that defines the turbine scroll passage and an inner circumferential edge portion that extends from the inner circumferential edge portion of the passage defining portion and along the metal plate. The scroll passage defining plate has an inner circumferential edge that is fixed between the turbine housing and the metal plate. The scroll passage defining plate is arranged in the turbine housing such that the outer circumferential edge portion of the passage defining portion is movable relative to the turbine housing.

An exhaust-gas turbocharger (1) having a turbine housing (2), having a compressor housing (3), having a bearing housing (4), which has a bearing housing axis (L), and having a connecting device (5), for connecting the bearing housing (4) to the compressor housing (3) and/or the turbine housing (2). The connecting device has a plurality of connecting elements (6) which each have a connecting element end face (7). The number of bores (8) in the compressor housing (3) corresponds to the number of connecting elements (6). The bores (8) and the connecting elements (6) inserted into the bores (8) are arranged at an acute angle (α) with respect to the bearing housing axis (L), and the connecting element end faces (7) rest on an associated bearing surface (9) of the bearing housing (4) and/or turbine housing (2).

A bearing housing (12) for a turbocharger having a rotatable shaft (14) passing through the bearing housing (12) with journal bearings (30) having tilting pads (40) for supporting the rotatable shaft (14) in the bearing housing (12). The tilting pads (40) may have oil supply holes (50) through each pad (40) to direct lubrication to each pad surface (44). The journal bearings (30) preferably have a circumferential groove (52) on an outer surface of the bearing aligned with the oil supply holes (50) to help feed oil to the oil supply holes (50).

A bearing structure of a turbocharger includes a rotor shaft, two angular ball bearings, a retainer, a housing, and an oil film damper. Each of the angular ball bearings includes an inner ring and an outer ring that are supported in relatively rotatable manner. The rotor shaft is inserted into the inner ring. The retainer holds the outer ring. The housing houses therein the rotor shaft, the angular ball bearings, and the retainer to constitute a bearing housing. The oil film damper is formed of oil in a film state and is interposed between the inner ring and an outer peripheral surface of the rotor shaft. The inner ring is configured to rotate with rotation of the rotor shaft via the oil film damper.

A bearing assembly for a turbocharger includes a turbine wheel-side ball bearing at a first axial end of a tubular body, a compressor impeller-side ball bearing at a second axial end of the tubular body, and a bearing housing. The bearing housing includes a first opposed wall opposed to an axially outer side of an outer race of the turbine wheel-side ball bearing, and a second opposed wall opposed to an axially outer side of an outer race of the compressor impeller-side ball bearing. The outer race of the turbine wheel-side ball bearing and the outer race of the compressor impeller-side ball bearing have axially outer end surfaces which are axially outwardly displaced from respective axial end surfaces of the tubular body so that oil films are present between the respective outer races and the corresponding opposed walls.

An oil-drain device for a thrust bearing includes: a rotor shaft; a collar member mounted to an outer periphery of the rotor shaft; a thrust bearing supporting the rotor shaft in an axial direction; and an oil-drain space forming member defining an oil-drain space through which lubricant oil leaking from a sliding portion of the thrust bearing flows, between the thrust bearing and the oil-drain space forming member. The oil-drain space includes: an oil-drain channel defined between a first end surface of the thrust bearing and a first end surface of the oil-drain space forming member, surrounding the flange portion of the collar member; and an oil-drain port formed below the oil-drain channel, for discharging the lubricant oil flowing through the oil-drain channel outside the oil-drain space. The oil-drain space is configured to guide the lubricant oil flowing through the oil-drain channel to outside the oil-drain space via the oil-drain port, along a flow direction of the lubricant oil flowing through the oil-drain channel from an upstream side toward a downstream side in a rotational direction of the rotor shaft.

An assembly includes a bearing having an annular shape, a bearing support radially outward from the bearing, a squeeze film damper having a first end adjacent the bearing and a second end adjacent the bearing support with the second end forming a squeeze film damping surface, and a first spring between the bearing and the bearing support with the first spring configured to resist a movement of the bearing to center a shaft radially inward from the bearing.

A product may be provided for use with a turbocharging system. A housing may be configured to house a bearing. A shaft may extend through the bearing. A turbine wheel may be connected to one end of the shaft. The housing may include a wall forming an opening and defining a surface facing the opening. The bearing may have a segment extending into the opening and mating with the surface. The wall may include an oil spray groove opening through the surface and having an outlet directed at the shaft.

A radial foil bearing includes: a bearing housing provided with an insertion hole; a top foil accommodated in the insertion hole; and a cover attached to an end surface of the bearing housing in an axial direction in which the insertion hole extends, wherein the top foil is rolled in a cylindrical shape in a state where two ends of the top foil intersect such that the two ends of the top foil are pulled out toward the bearing housing, and the cover faces, in the axial direction, at least either one of the two ends of the top foil, and an engagement member attached to the bearing housing and engaging with the top foil.