Emission control system

An emission control system for an internal combustion engine, the combination comprising:

• a fluidic amplifier having a supply port and an outlet port,
• a recirculation passageway for connecting the supply port of said fluidic amplifier to a source of exhaust gas having a pressure variable in accordance with the operation of the internal combustion engine and for connecting the outlet port to an intake manifold for recirculating exhaust gas through the engine,
• said recirculation passageway connecting the supply port of said fluidic amplifier to the exhaust system of the internal combustion engine,
• said fluidic amplifier having a power jet chamber in fluid communication with the supply port and a receiver chamber in fluid communication with the outlet port,
• said fluidic amplifier having wall means defining an intermediate space between a receiver chamber and the power jet chamber with the nozzle portion of the power jet chamber directed toward the receiver chamber,
• said fluidic amplifier having a vent chamber opening into the intermediate space and in fluid communication with a vent port for venting to a relatively low fluid pressure so as to create a differential pressure with the power jet chamber to form a relatively high velocity stream of recirculating exhaust gas acting as a beam for passage through the intermediate space to the receiver chamber with the amount of recirculated exhaust gas varying in accordance with the pressure of the exhaust gas supplied to the supply port,
• a venturi disposed in the exhaust system of the internal combustion engine, and
• a vent passageway connecting the vent port of said fluidic amplifier to said venturi.

An emission control system for an internal combustion engine, the combination comprising:

• a fluidic amplifier having a supply port and an outlet port,
• a recirculation passageway for connecting the supply port of said fluidic amplifier to a source of exhaust gas having a pressure variable in accordance with the operation of the internal combustion engine and for connecting the outlet port to an intake manifold for recirculating exhaust gas through the engine,
• said fluidic amplifier having a power jet chamber in fluid communication with the supply port and a receiver chamber in fluid communication with the outlet port,
• said fluidic amplifier having wall means defining an intermediate space between a receiver chamber and the power jet chamber with the nozzle portion of the power jet chamber directed toward the receiver chamber,
• said fluidic amplifier having a vent chamber opening into the intermediate space and in fluid communication with a vent port for venting to a relatively low fluid pressure so as to create a differential pressure with the power jet chamber to form a relatively high velocity stream of recirculating exhaust gas acting as a beam for passage through the intermediate space to the receiver chamber with the amount of recirculated exhaust gas varying in accordance with the pressure of the exhaust gas supplied to the supply port,
• valve means operable in response to air signals for controlling the flow of exhaust gas from the outlet port of said fluidic amplifier through the recirculating passageway, and
• control means operable in response to selected operating conditions of the internal combustion engine for supplying a digital air signal to said valve means to effect opening of the recirculation passageway to the flow of exhasut gas.

In an emission control system for an internal combustion engine, the combination comprising:

• a passageway for recirculating exhaust gas to an intake manifold of the internal combustion engine,
• valve means operable in response to air signals for opening or closing to control the flow of recirculating exhaust gas through said passageway,
• control means operable in response to selected operating conditions of the internal combustion engine for supplying a digital air signal to said valve means to effect opening of said passageway to the flow of recirculating exhaust gas,
• said valve means including a valve member supported for movement in the recirculation passageway relative to a valve seat,
• a closed chamber in fluid communication with said control means for receiving digital air signals and being partially formed by a diaphragm movably associated with said valve member,
• resilient biasing means urging said diaphragm in a direction to close the valve member against the valve seat in the recirculation passageway,
• said control means being in the form of a fluidic NOR gate operable in response to analog signals representative of selected engine operating conditions for supplying digital air signals to the closed chamber of said valve means to effect movement of the valve member,
• said fluidic NOR gate having a supply port for receiving a supply of compressed air to provide an air stream therethrough and a first channel leading from the supply port to an outlet port open to the atmosphere for normally venting an air stream received through the supply port,
• said fluidic NOR gate having a second channel leading from the first channel and being in fluid communication with the closed chamber of said valve means, and
• said fluidic NOR gate having a control jet in fluid communication with the carburetor for enabling a vacuum signal indicative of a predetermined air flow through the carburetor to effect switching of the air stream from the first channel to the second channel for opening said valve means.