Working fluid circuit for a turbocharged engine having exhaust gas recirculation

Claim 1

An engine working fluid circuit for a turbocharged internal combustion engine that employs exhaust gas recirculation, said working fluid circuit comprising: an exhaust gas passage through which exhaust gas under pressure flows from the internal combustion engine, a charge air passage, and a turbo charger operatively driven by the exhaust gas flowing from the internal combustion engine and acting to provide pressurized air to said charged air passage; an exhaust gas recirculation passage extending between said exhaust gas passage and said charge air passage bypassing said turbo charger and providing a path for recirculating a predetermined amount of exhaust gas into said charge air passage so as to add mix the exhaust gas with the charge air; an intake passage for providing intake air to the internal combustion engine; a single charge air cooler including an inlet operatively connected in fluid communication with said charge air passage and an outlet operatively connected in fluid communication with said intake passage, said single charge air cooler further including a plurality of cooling passages spaced from one another and extending between said inlet and said outlet that may be exposed to a flow of ram air, said plurality of cooling passages thereby operatively interconnecting and providing fluid communication between said charge air passage and said intake passage while providing a cooling path for the mixed charged air and recirculated exhaust gas; and at least one bypass passage extending between said inlet and said outlet of said single charge air cooler separate from said plurality of cooling passages and adapted to provide fluid communication between said inlet and said outlet, said bypass passage having a bypass valve movable between open and closed positions to proportionally control the flow of mixed charge air and recirculated exhaust gas between said cooling passages and said bypass passage.