Abstract: A system and method for controlling an internal combustion engine having an EGR valve determine a base valve position to deliver a target flow using a stored map and adjust the base position in response to differential pressure across an orifice in the EGR flow to move the valve to a position different from the base position to provide the target flow.

Abstract: A system and method for controlling a multiple cylinder internal combustion engine include a mechanically operated exhaust gas recirculation valve having a spring-biased pintle with a surface area sized to generate a spring-opposing force to open a valve chamber entrance when an exhaust pressure differential exceeds a first threshold to allow exhaust gas to flow toward an intake and to close a valve chamber exit spaced from the chamber entrance to block exhaust gas flowing to the intake when the pressure differential exceeds a second threshold. The valve operates to limit or block external EGR flow at low load such as during starting and idle as well as at wide-open throttle while metering EGR flow for mid-to-high loads.

Abstract: A system and method for controlling EGR of an internal combustion engine is presented. The system is capable of controlling EGR over a wide range of flow rates.

Abstract: An exhaust gas recirculation system has an EGR valve disposed in an EGR duct connecting an engine intake and exhaust. A diaphragm of said EGR valve is actuated via vacuum from the engine intake, the application of the vacuum is controlled via an electronic valve regulator (EVR). The EVR is provided a fixed signal to cause it to be fully open when it is determined that the engine is about to encounter a condition in which there is insufficient vacuum to open the EGR valve. The EVR is provided a variable signal during other operating conditions in which there is sufficient vacuum to open the EGR valve.

Abstract: A system and method for controlling a multiple cylinder internal combustion engine include a mechanically operated exhaust gas recirculation valve having a spring-biased pintle with a surface area sized to generate a spring-opposing force to open a valve chamber entrance when an exhaust pressure differential exceeds a first threshold to allow exhaust gas to flow toward an intake and to close a valve chamber exit spaced from the chamber entrance to block exhaust gas flowing to the intake when the pressure differential exceeds a second threshold. The valve operates to limit or block external EGR flow at low load such as during starting and idle as well as at wide-open throttle while metering EGR flow for mid-to-high loads.

Abstract: A system and method for controlling EGR of an internal combustion engine is presented. The system is capable of controlling EGR over a wide range of flow rates.

Abstract: The control signal on the EGR valve is based on an indication of whether the engine will soon encounter a condition with insufficient vacuum in the engine intake to operate the EGR valve. When such condition is about to be encountered, the desire is to supply a vacuum on the EGR valve and to hold such vacuum so that the EGR valve remains open. An EGR system is disclosed which has an electronic valve regulator (EVR) coupled to the EGR valve and an engine intake. A disk within the body of the EVR rises when voltage is applied to the coil in the EVR causing intake vacuum to be communicated to the EGR valve. A stop within the EVR allows the disk to seal when voltage is applied, thereby allowing the engine intake vacuum to be maintained. The stop is in the shape of a ring within the EVR.

Abstract: An exhaust gas recirculation system directs exhaust gasses from an exhaust manifold to an intake manifold of an internal combustion engine. The exhaust gasses travel from the exhaust manifold, first passing through a flow control valve and then through a measuring orifice before entering the intake manifold. Pressure upstream of the orifice is used, along with correction pressure downstream of the orifice, to measure and control exhaust gas flow. Further, manifold pressure is determined from downstream pressure and the used along with the measured exhaust gas flow to calculated a cylinder air charge amount.

Abstract: A method for controlling a diesel engine exhaust gas recirculation system is described. In particular, a simplified diesel engine system is provided where presence of exhaust gas recirculation of flow is controlled via a two-position valve, while a quantity of exhaust gas recirculation is adjusted by varying the throttle valve. In this way, a reduced cost diesel exhaust gas recirculation system is achieved that provides the functionality of having variable amounts of exhaust gas recirculation.

Abstract: An exhaust gas recirculation system directs exhaust gasses from an exhaust manifold to an intake manifold of an internal combustion engine. The exhaust gasses travel from the exhaust manifold, first passing through a flow control valve and then through a measuring orifice before entering the intake manifold. Pressure upstream of the orifice is used, along with correction pressure downstream of the orifice, to measure and control exhaust gas flow. Further, manifold pressure is determined from downstream pressure and the used along with the measured exhaust gas flow to calculated a cylinder air charge amount.

Abstract: An exhaust gas recirculation systems directs exhaust gasses from an exhaust manifold to an intake manifold of an internal combustion engine. The exhaust gasses travel from the exhaust manifold, first passing through a flow control valve and then through a measuring orifice before entering the intake manifold. Pressure upstream of the orifice is used, along with correction pressure downstream of the orifice, to measure and control exhaust gas flow. Further, manifold pressure is determined from downstream pressure and the used along with the measured exhaust gas flow to calculated a cylinder air charge amount.

Abstract: A method for controlling an engine during sensor degradation uses a remaining active sensor. The engine has an exhaust gas recirculation system utilizing pressure sensors upstream and downstream of an orifice. The downstream pressure sensor is coupled to the engine intake manifold and is also used for engine air-fuel ratio control.

Abstract: A method for controlling a diesel engine exhaust gas recirculation system is described. In particular, a simplified diesel engine system is provided where presence of exhaust gas recirculation of flow is controlled via a two-position valve, while a quantity of exhaust gas recirculation is adjusted by varying the throttle valve. In this way, a reduced cost diesel exhaust gas recirculation system is achieved that provides the functionality of having variable amounts of exhaust gas recirculation.

Abstract: An exhaust gas recirculation systems directs exhaust gasses from an exhaust manifold to an intake manifold of an internal combustion engine. The exhaust gasses travel from the exhaust manifold, first passing through a flow control valve and then through a measuring orifice before entering the intake manifold. Pressure upstream of the orifice is used, along with correction pressure downstream of the orifice, to measure and control exhaust gas flow. Further, manifold pressure is determined from downstream pressure and the used along with the measured exhaust gas flow to calculated a cylinder air charge amount.

Abstract: A method for controlling an engine during sensor degradation uses a remaining active sensor. The engine has an exhaust gas recirculation system utilizing pressure sensors upstream and downstream of an orifice. The downstream pressure sensor is coupled to the engine intake manifold and is also used for engine air-fuel ratio control.

Abstract: A method for measuring flow through an orifice using an upstream gauge pressure sensor and a downstream absolute pressure sensor determines atmospheric pressure when flow through the orifice is substantially zero, or less than a predetermined value. Then, this estimate, along with the upstream and downstream pressure sensors are used to measure flow through the orifice.

Abstract: An exhaust gas recirculation systems directs exhaust gasses from an exhaust manifold to an intake manifold of an internal combustion engine. The exhaust gasses travel from the exhaust manifold, first passing through a flow control valve and then through a measuring orifice before entering the intake manifold. Pressure upstream of the orifice is used, along with correction pressure downstream of the orifice, to measure and control exhaust gas flow. Further, manifold pressure is determined from downstream pressure and the used along with the measured exhaust gas flow to calculated a cylinder air charge amount.

Abstract: A method for estimating pressure surround an engine uses a gauge pressure sensor upstream of an orifice and an absolute pressure sensor downstream of the orifice. In particular, atmospheric pressure can be determined when flow through the orifice is below a predetermined threshold.

Abstract: An EGR system using pressure-based feedback control includes an actuator for moving an EGR valve between a closed position and an open position, and a position sensor for detecting the position of the EGR valve and generating a position output signal. A processing circuit receives the position output signal and transmits electrical control signals to energize the actuator and move the EGR valve. A controller includes control logic operative to determine the position for the EGR valve using open loop control during transient behavior and closed loop control for steady state accuracy.

Abstract: An exhaust gas recirculation systems directs exhaust gasses from an exhaust manifold to an intake manifold of an internal combustion engine. The exhaust gasses travel from the exhaust manifold, first passing through a flow control valve and then through a measuring orifice before entering the intake manifold. Pressure difference across the orifice is used, along with correction factors based on the pressure difference and pressure downstream of the orifice, to measure and control exhaust gas flow. Further, manifold pressure is determined from downstream pressure and the used along with the measured exhaust gas flow to calculated a cylinder air charge amount.