A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A supercharged internal combustion engine has a supercharger operable to selectively supply a mass of air from below through above atmospheric air pressure according to the operating requirements of the engine. The supercharger has a shuttle combined with a throttle valve that controls the mass of air directed to an air mass bypass opening and supplied to the internal combustion engine. The shuttle has rollers that ride on rails that allow the shuttle to move to open and close the air mass bypass opening in communication with a casing that directs a mass of atmospheric air and a bypass mass of air interfused with the mass of atmospheric air to an air mass inlet of the supercharger.

A method of and apparatus for operating a supercharger for an automotive engine is disclosed. The supercharger has: an input shaft for coupling to an engine crankshaft, and coupled to the rotor of a first electrical machine and a first component of an epicyclic gear train; and an output shaft connected to a compressor and a second component of the epicyclic gear train; wherein the third component of the epicyclic gear train is connected to the rotor of a second electrical machine. The first electrical machine is selectively operable to supply electrical energy to the second electrical machine. The method includes the steps of: (a) calculating a required speed of the second electrical machine that would give rise to a required pressure at an outlet of the compressor; and (b) setting the speed of the second electrical machine to the calculated required speed.

A method of and apparatus for operating a supercharger for an automotive engine is disclosed. The supercharger has: an input shaft for coupling to an engine crankshaft, and coupled to the rotor of a first electrical machine and a first component of an epicyclic gear train; and an output shaft connected to a compressor and a second component of the epicyclic gear train; wherein the third component of the epicyclic gear train is connected to the rotor of a second electrical machine. The first electrical machine is selectively operable to supply electrical energy to the second electrical machine. The method includes the steps of: (a) calculating a required speed of the second electrical machine that would give rise to a required pressure at an outlet of the compressor; and (b) setting the speed of the second electrical machine to the calculated required speed.

A supercharger (12) with two separate sets of rotors (22, 24) arranged in parallel with one another is provided in an engine assembly. Both sets of rotors are used to boost air flow during high engine air flow conditions, and only one of the sets of rotors is operable to transfer torque generated by the throttling loss pressure drop as stored energy in a load device during low air flow conditions. The captured throttling losses may be electrical energy stored in a battery via a motor/generator such as during vehicle cruising.