Turbocharger and EGR system

An apparatus comprising:

• a turbocharger with a turbine and an inlet passage, the inlet passage having a first flow resistance;
• a restrictor valve located proximate to the inlet passage, said restrictor valve having a variable flow resistance selectively variable between a maximum and a minimum, the maximum flow resistance being greater than the first flow resistance, said restrictor valve having a first inlet and a first outlet, the first outlet being in fluid communication with the turbine;
• and
• an exhaust gas recirculation valve with a second inlet and a second outlet and a valve member selectively movable between opened and closed positions, the second inlet being in fluid communication with the first inlet of said restrictor valve, the second inlet and second outlet being in fluid communication in the opened position, the second outlet being substantially sealed from the second inlet in the closed position;
• wherein said restrictor valve is selectively variable independently of the movement of said valve member of said exhaust gas recirculation valve.

An apparatus comprising:

• an internal combustion engine accepting intake gas and producing exhaust gas;
• a restrictor valve with an inlet for accepting exhaust gas from an internal combustion engine, a first outlet, a second outlet, and a flow restricting device movable between first and second positions, in which the first position substantially restricts fluid communication from the inlet to the first outlet and from the inlet to the second outlet, and the second position substantially restricts fluid communication from the inlet to the first outlet;
• and
• a turbocharger with a turbine inlet in fluid communication with the first outlet of said restrictor valve;
• wherein exhaust gas from the second outlet is mixed with intake gas.

A system comprising:

• an internal combustion engine producing exhaust gas and accepting intake gas, the exhaust gas being at a first pressure and the intake gas being at a second pressure, said engine having an intake manifold;
• a restrictor valve receiving exhaust gas from said engine, said restrictor valve having a variable flow resistance and an actuatable flow restricting device for varying the flow resistance of said restrictor valve, said restrictor valve having a first outlet;
• a turbocharger with a turbine with a first inlet, the first inlet being in fluid communication with the first outlet of said restrictor valve;
• an exhaust gas recirculation valve having a second inlet accepting the exhaust gas and a second outlet in fluid communication with said intake manifold;
• a first sensor for providing a first signal corresponding to the first pressure;
• a second sensor for providing a second signal corresponding to the second pressure;
• and
• a controller responsive to said first signal and said second signal, said controller actuating said flow restricting device to increase the first pressure so that the first pressure is greater than the second pressure.

A turbocharger for an internal combustion engine producing exhaust gas, comprising:

• a turbine with a first inlet;
• a compressor with a first outlet;
• a restrictor valve for restricting the flow of exhaust gas into the first inlet of said turbine;
• a poppet valve with a second inlet and a second outlet, the second inlet being in fluid communication with the first inlet of said turbine, the second outlet being in fluid communication with the first outlet of said compressor, said poppet valve having an opened position in which the second outlet is in fluid communication with the second inlet and a closed position in which the second outlet is substantially sealed from the second inlet;
• and
• a support housing assembly which supports said turbine, said compressor, said restrictor valve, and said poppet valve.

A method for recirculating a predetermined flow of exhaust gas into the intake manifold of a turbocharged engine, comprising:

• providing an internal combustion engine, a turbocharger for receiving exhaust gas from the engine at a first pressure and providing intake gas to the engine at a second pressure, a restrictor valve, and an exhaust gas recirculation valve;
• adjusting the restrictor valve to increase the first exhaust pressure provided to the turbocharger until the first exhaust pressure is greater than the second intake pressure;
• opening an exhaust gas recirculation valve to permit recirculation of exhaust gas into the intake gas;
• and
• readjusting the restrictor valve to achieve the predetermined exhaust gas flow.