A turbocharger system can include a housing that includes a through bore, a plurality of lubricant bores, a plurality of lubricant bore to through bore openings and a recessed compressor-side surface that defines in part a passage that fluidly couples at least two of the lubricant bores; a rolling element bearing unit disposed at least in part in the through bore of the housing; and, a plate that covers at least a portion of the recessed compressor-side surface of the housing.

A turbocharger comprises: a rolling bearing provided with a plurality of rolling elements arranged between a raceway formed on an inner ring and a raceway formed on an outer ring; and a housing for holding the outer ring. The housing is provided with: a first dam for restricting the outflow of a lubricant through a first discharge passage for discharging the lubricant from the outer ring; and a second dam for restricting the outflow of the lubricant through a second discharge passage for discharging the lubricant from an opening formed so as to be in communication with an axially intermediate portion of the outer ring and with a peripheral wall of a space.

Turbochargers typically have separate hydrodynamic journal and thrust bearings. A turbocharger thrust bearing for a turbocharger is provided that merges the function of a journal bearing into a thrust bearing while maintaining the thrust bearing function to produce a turbocharger with a reduced axial space envelope. Such a thrust bearing includes a bore contoured to have a plurality of taper-land pairs distributed circumferentially about the bore. As a result, the axial length of the turbocharger bearing housing and shaft can be reduced.

An exhaust gas turbocharger for an internal combustion engine may include a rotor with a turbine wheel of a turbine, a compressor wheel of a compressor and a shaft. The shaft may be connected to the turbine wheel and to the compressor wheel in a rotationally fixed manner. A bearing cartridge may be included for mounting the rotor in a housing. The bearing cartridge may have an inner sleeve arranged on the shaft axially between the turbine wheel and the compressor wheel with respect to an axis of rotation and an outer sleeve arranged coaxial thereto. The outer sleeve may be rotatably mounted on the inner sleeve via at least one rolling body. At least two damping rings may be included which are coaxially arranged on the outer sleeve axially spaced from one another and supported on a respective bearing section of the housing.

A bearing structure of a turbocharger includes a rotor shaft, a ball bearing, and a housing. An inner ring of the ball bearing has the rotor shaft inserted therein. The oil film damper is formed between the inner ring and an outer peripheral surface of the rotor shaft. The inner ring rotates with rotation of the rotor shaft via the oil film damper. An oil discharge path for scattering oil discharged from the oil film damper radially outside, is provided at least either on one end surface of the inner ring in an axial direction or on an opposing surface opposed to the inner ring, of a collar. The oil discharge path is formed of a groove that is arranged in a manner to be gradually apart from the oil film damper in the axial direction as going radially outside.

A turbocharger includes a housing and a rotary assembly disposed within the housing and including a turbine wheel and a compressor wheel attached to one another by a shaft. A bearing is disposed in the housing and rotatably supports the shaft. The bearing includes a pair of inner bearing surfaces that engage opposite ends of the shaft and a pair of outer bearing surfaces that engage the housing. The pair of inner bearing surfaces have a first axial dimension and the pair of outer bearing surfaces have a second axial dimension that is smaller than the first axial dimension.

An object of the present invention is to provide a bearing structure of a turbocharger that can prevent generation of unusual noise and a decrease in operation efficiency and that can reduce manufacturing costs. The bearing structure of a turbocharger to accomplish such an object, includes a rotor shaft, a ball bearing, a retainer, and a housing. The rotor shaft is provided with a turbine impeller mounted on a first end and a compressor impeller mounted on a second end.

The ball bearing includes an inner ring and an outer ring that are supported in relatively rotatable manner. The retainer holds the outer ring. Between the inner ring and an outer peripheral surface of the rotor shaft, oil in a film state is interposed to form an oil film damper.

The present disclosure relates to a thrust bearing which is disposed to face a thrust collar provided in a rotation shaft. The thrust bearing includes a top foil, a back foil, and a base plate. The back foil includes a plurality of back foil pieces which are arranged in a circumferential direction of the base plate, and the top foil includes a plurality of top foil pieces which are respectively disposed on the back foil pieces. An inner peripheral recessed portion is formed at a portion which supports an inner peripheral side end of the back foil piece in a surface supporting the back foil in the base plate.

A bearing housing for a turbocharger is disclosed. The bearing housing includes a first end proximate to a turbine wheel of the turbocharger and a second end proximate to a compressor wheel of the turbocharger. The bearing housing further includes a central chamber disposed between the first end and the second end and configured to house, at least, the shaft. The bearing housing further includes an oil drain disposed radially outward of the shaft and configured for directing oil out of the bearing housing and an oil core disposed radially outward of the shaft and radially inward of the oil drain, the oil core configured for communicating oil towards the oil drain and having an inner wall. The bearing housing includes one or more strakes protruding radially inward from the inner wall, the one or more strakes configured to direct oil within the oil core towards the oil drain.

A turbocharger includes: a bearing provided in a turbocharger body, and configured to rotatably support a turbine shaft in an insertion hole formed in the bearing; and an opposing portion which faces an end surface of the bearing in an axial direction of the turbine shaft. An end-surface guide portion is provided to any one of an opposing surface of the bearing which faces the opposing portion, and an opposing surface of the opposing portion which faces the bearing. The end-surface guide portion configured to make the insertion hole and an outer peripheral edge of the end surface of the bearing in radial directions of the turbine shaft communicate with each other extends forward in a rotational direction of the turbine shaft from a part of the end surface of the bearing which communicates with the insertion hole.