Methods and systems for operating an engine that includes four compressors for two cylinder banks are described. In one example, output of two compressors and positions of valves are adjusted responsive to an engine air flow amount to prevent air from back flowing through a compressor. Output from the two compressors may be combined for higher engine air flow amounts.

Methods and systems for operating an engine that includes four compressors for two cylinder banks are described. In one example, output of two compressors and positions of valves are adjusted responsive to an engine air flow amount to prevent air from back flowing through a compressor. Output from the two compressors may be combined for higher engine air flow amounts.

An object is to provide a structure and a method of joining a nozzle vane and a lever, and a variable geometry turbocharger, capable of reducing breakage of a welded part between a shaft portion of the nozzle vane and the lever during usage of the same by reducing generation of a hot crack in weld metal at the welded part. A joint structure includes: a nozzle vane 2 disposed in an exhaust passage for guiding exhaust gas to a turbine wheel 34 of a variable geometry turbocharger 500, and including a shaft portion 2a; and a lever 1 including a fitting surface 42a fitted with a peripheral surface 72 on one end side of the shaft portion, for transmitting torque to the shaft portion to adjust a vane angle of the nozzle vane. Weld metal 50 at a welded part 40 between the lever and the nozzle vane is formed so that a center position 64 of the weld metal is disposed inside a position 17 of the fitting surface with respect to a radial direction of the shaft portion.

An object is to provide a structure and a method of joining a nozzle vane and a lever, and a variable geometry turbocharger, capable of reducing breakage of a welded part between a shaft portion of the nozzle vane and the lever during usage of the same by reducing generation of a hot crack in weld metal at the welded part. A joint structure includes: a nozzle vane 2 disposed in an exhaust passage for guiding exhaust gas to a turbine wheel 34 of a variable geometry turbocharger 500, and including a shaft portion 2a; and a lever 1 including a fitting surface 42a fitted with a peripheral surface 72 on one end side of the shaft portion, for transmitting torque to the shaft portion to adjust a vane angle of the nozzle vane. Weld metal 50 at a welded part 40 between the lever and the nozzle vane is formed so that a center position 64 of the weld metal is disposed inside a position 17 of the fitting surface with respect to a radial direction of the shaft portion.

A supercharger outlet resonator comprises a housing, a first surface comprising a first opening and a housing axis bisecting the first opening, and a second surface comprising a second opening, the second surface located parallel to the first surface. A channel is perpendicular to the housing axis and connects the first opening to the second opening. The channel comprises at least one sidewall. An envelope is fluidly separated from the channel by the at least one sidewall, the envelope at least partially surrounds the channel, and the envelope extends from the first surface to the second surface. The envelope comprises a third opening and at least one second sidewall. A noise-reducing material located on the housing.

A supercharger outlet resonator comprises a housing, a first surface comprising a first opening and a housing axis bisecting the first opening, and a second surface comprising a second opening, the second surface located parallel to the first surface. A channel is perpendicular to the housing axis and connects the first opening to the second opening. The channel comprises at least one sidewall. An envelope is fluidly separated from the channel by the at least one sidewall, the envelope at least partially surrounds the channel, and the envelope extends from the first surface to the second surface. The envelope comprises a third opening and at least one second sidewall. A noise-reducing material located on the housing.

A spacer is disposed between a rotor and a bearing of an electric supercharger to fix the rotor. The spacer has a tapered surface with a diameter decreasing toward the bearing in an outer circumferential surface of the spacer. An area of an end surface of the spacer on a rotor side is larger than an area of an end surface of the spacer on a bearing side. A balance correction part that corrects balance of the spacer is disposed inside a recess formed in the end surface. A region of the end surface located on an outer side of the recess relative to a central axis of the spacer constitutes a surface coming in contact with the rotor.

A spacer is disposed between a rotor and a bearing of an electric supercharger to fix the rotor. The spacer has a tapered surface with a diameter decreasing toward the bearing in an outer circumferential surface of the spacer. An area of an end surface of the spacer on a rotor side is larger than an area of an end surface of the spacer on a bearing side. A balance correction part that corrects balance of the spacer is disposed inside a recess formed in the end surface. A region of the end surface located on an outer side of the recess relative to a central axis of the spacer constitutes a surface coming in contact with the rotor.

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 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.