Turbocharging system for an internal combustion engine
AssigneeNgk Spark Plug Co., Ltd.
InventorsNoboru Ishida, Mitsuyoshi Kawamura, Toshiyuki Ishihara
Life of this patent
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Abstract
A turbocharging system for an internal combustion engine improves performance and efficiency under low-speed, high-load operating conditions by adding secondary air to the exhaust gas upstream of the turbocharger. The secondary air combusts with unburned fuel contained in the exhaust gas to increase the temperature and pressure of the exhaust gas driving the turbocharger. Secondary air is added only when the exhaust gas temperature is above a prescribed temperature and the air-fuel ratio of the exhaust gas is below a prescribed ratio.
Claims19
A turbocharging system for an internal combustion engine having an exhaust system including an exhaust manifold for removing exhaust gas from said engine, said turbocharging system comprising:
- a. a turbocharger including a turbine portion and a compressor portion connected together by shaft means, said turbine portion being in flow communication with said exhaust system and being rotatably driven by said exhaust gas;
- and
- b. secondary air supply means for adding secondary air to said exhaust gas upstream of said turbine portion with respect to the direction of flow of said exhaust gas when the air-fuel ratio of said exhaust gas is below a prescribed ratio, said secondary air combusting with unburned fuel remaining in said exhaust gas to increase the temperature and pressure of said exhaust gas driving said turbine portion.
A turbocharging system for an internal combustion engine having an exhaust system including an exhaust manifold for removing exhaust gas from said engine, said turbocharging system comprising:
- a. a turbocharger including a turbine portion and a compressor portion connected together by shaft means, said turbine portion being in flow communication with said exhaust system and being rotatably driven by said exhaust gas;
- b. secondary air supply means for adding secondary air to said exhaust gas through a secondary air induction port located upstream of said turbine portion with respect to the direction of flow of said exhaust gas, said secondary air combusting with unburned fuel remaining in said exhaust gas to increase the temperature and pressure of said exhaust gas driving said turbine portion;
- c. means for detecting and producing signals communicating the air-fuel ratio of said exhaust gas in said exhaust system;
- d. means for detecting and producing signals communicating the temperature of said exhaust gas in said exhaust system upstream of said turbine portion;
- and
- e. control means communicating with said air-fuel ratio detection means and said exhaust temperature detection means for controlling the amount of secondary air added to said exhaust gas by said secondary air supply means in response to said signals produced by said air-fuel ratio detecting means and said exhaust temperature detecting means, said control means actuating said secondary air supply means when said air-fuel ratio detecting means detects an exhaust gas air-fuel ratio below a prescribed ratio and said exhaust temperature detecting means detects an exhaust gas temperature above a prescribed temperature.
A turbocharging system for an internal combustion engine having an exhaust system including an exhaust manifold for removing exhaust gas from said engine, said turbocharging system comprising:
- a. a turbocharger including a turbine portion and a compressor portion connected together by shaft means, said turbine portion being in flow communication with said exhaust system and being rotatably driven by said exhaust gas;
- and
- b. secondary air supply means for adding secondary air to said exhaust gas upstream of said turbine portion with respect to the direction of flow of said exhaust gas when the temperature of said exhaust gas is above a prescribed temperature and the air-fuel ratio of said exhaust gas is below a prescribed ratio, said secondary air combusting with unburned fuel remaining in said exhaust gas to increase the temperature and pressure of said exhaust gas driving said turbine portion.
Dependencies are inferred from the claim text.