A method of operating a supercharger (10) for an automotive engine (20) is disclosed. A supercharger (10) has an input shaft (30) for coupling to a crank shaft (22) of the engine and also for coupling to the rotor of a first electrical machine (40) and the annulus of an epicyclic gear train (60). An output shaft (70) is connected to a compressor (80) and a sun gear of the epicyclic gear train (60). A carrier carrying planet gears of the epicyclic gear train (60) is connected to the rotor of a second electrical machine (50). The first electrical machine (40) is selectively operable to supply electrical energy to the second electrical machine (50). The second electrical machine (50) is selectively operable as a motor or a generator to accelerate or decelerate the compressor (80), thereby tending to increase or decrease the power output of the engine. The first electrical machine (40) is selectively operable as a motor or a generator to control the torque transmitted from the input shaft (30) back to the crank shaft (22) caused by operation of the second electrical machine (50).

A method of operating a supercharger (10) for an automotive engine (20) is disclosed. A supercharger (10) has an input shaft (30) for coupling to a crank shaft (22) of the engine and also for coupling to the rotor of a first electrical machine (40) and the annulus of an epicyclic gear train (60). An output shaft (70) is connected to a compressor (80) and a sun gear of the epicyclic gear train (60). A carrier carrying planet gears of the epicyclic gear train (60) is connected to the rotor of a second electrical machine (50). The first electrical machine (40) is selectively operable to supply electrical energy to the second electrical machine (50). The second electrical machine (50) is selectively operable as a motor or a generator to accelerate or decelerate the compressor (80), thereby tending to increase or decrease the power output of the engine. The first electrical machine (40) is selectively operable as a motor or a generator to control the torque transmitted from the input shaft (30) back to the crank shaft (22) caused by operation of the second electrical machine (50).

A rotor for a supercharging device may include an arrangement; the arrangement may include a compressor wheel operatively coupled to a turbine wheel. A cup-shaped bearing bush configured to receive a radial air bearing may be arranged on at least one longitudinal end of the arrangement. The bearing bush may define an interior including at least one hollow space and a plurality of stiffening ribs extending into the at least one hollow space.

A rotor for a supercharging device may include an arrangement; the arrangement may include a compressor wheel operatively coupled to a turbine wheel. A cup-shaped bearing bush configured to receive a radial air bearing may be arranged on at least one longitudinal end of the arrangement. The bearing bush may define an interior including at least one hollow space and a plurality of stiffening ribs extending into the at least one hollow space.

The internal combustion engine comprises a supercharger, a variable valve timing mechanism able to change a valve overlap amount, a catalyst arranged in an exhaust passage and able to store oxygen, a downstream side air-fuel ratio sensor arranged at a downstream side of the catalyst in an exhaust flow direction and able to detect an air-fuel ratio of outflowing exhaust gas flowing out from the catalyst, and a scavenging control device able to control a scavenging amount by controlling the valve overlap amount by the variable valve timing mechanism. The scavenging control device reduces the valve overlap amount when an air-fuel ratio detected by the downstream side air-fuel ratio sensor changes from less than a lean judged air-fuel ratio leaner than a stoichiometric air-fuel ratio to the lean judged air-fuel ratio or more during scavenging.

The internal combustion engine comprises a supercharger, a variable valve timing mechanism able to change a valve overlap amount, a catalyst arranged in an exhaust passage and able to store oxygen, a downstream side air-fuel ratio sensor arranged at a downstream side of the catalyst in an exhaust flow direction and able to detect an air-fuel ratio of outflowing exhaust gas flowing out from the catalyst, and a scavenging control device able to control a scavenging amount by controlling the valve overlap amount by the variable valve timing mechanism. The scavenging control device reduces the valve overlap amount when an air-fuel ratio detected by the downstream side air-fuel ratio sensor changes from less than a lean judged air-fuel ratio leaner than a stoichiometric air-fuel ratio to the lean judged air-fuel ratio or more during scavenging.

An air intake duct of a motorcycle extends rearwardly from a front portion of a motorcycle body so as to pass laterally of the left side of a motorcycle frame structure, and incoming wind is supplied as an intake air through the air intake duct to a combustion engine. The air intake duct is divided in a widthwise direction of the motorcycle. An upper dividing face of the air intake duct is disposed inward of an intermediate position, in a motorcycle widthwise direction, of the air intake duct.

An air intake duct of a motorcycle extends rearwardly from a front portion of a motorcycle body so as to pass laterally of the left side of a motorcycle frame structure, and incoming wind is supplied as an intake air through the air intake duct to a combustion engine. The air intake duct is divided in a widthwise direction of the motorcycle. An upper dividing face of the air intake duct is disposed inward of an intermediate position, in a motorcycle widthwise direction, of the air intake duct.

A system for recovering waste heat energy for a motor assisted turbocharger, including a turbine, a first power transmission device connected on a first side to the turbine, a drive gear disposed about and connected on a first side to a second side of the first power transmission device, a second power transmission device connected on a first side to a second side of the drive gear, and a compressor connected to a second side of the second power transmission device. The system further includes a motor gear drivingly connected to the drive gear, a motor generator connected to the motor gear, a waste heat recovery circuit including an expander, an output gear connected to the expander and drivingly connected to the motor gear.

A system for recovering waste heat energy for a motor assisted turbocharger, including a turbine, a first power transmission device connected on a first side to the turbine, a drive gear disposed about and connected on a first side to a second side of the first power transmission device, a second power transmission device connected on a first side to a second side of the drive gear, and a compressor connected to a second side of the second power transmission device. The system further includes a motor gear drivingly connected to the drive gear, a motor generator connected to the motor gear, a waste heat recovery circuit including an expander, an output gear connected to the expander and drivingly connected to the motor gear.