摘要:
An EGR valve position control method controls a position of an EGR valve according to a pressure change across the valve and a desired EGR valve position. The method calculates a desired EGR valve position and generates one or more duty cycle control terms based on a difference between the desired EGR valve position and an actual EGR valve position. Additionally, the method provides feedforward control based on the pressure change and the desired EGR valve position in order to generate feedforward duty cycle control terms. The method controls the position of the EGR valve based on the duty cycle control terms.
摘要:
A system and method for utilizing fuel as an on-board reductant for selective catalytic reduction of NOx is provided and includes a controller for controlling an engine to produce a lean first exhaust stream and a rich second exhaust stream that are received in respective first and second passageways of a dual path aftertreatment system. The rich second exhaust stream reacts with NOx stored in a NOx storage and reduction catalyst of the second passageway to regenerate this catalyst and generate ammonia. The first exhaust stream and the second exhaust stream having the generated ammonia are combined in a downstream common passageway to form a combined lean exhaust gas stream where the ammonia carried therein is stored or used by an SCR catalyst of the common passageway for NOx reduction. The engine is subsequently controlled to produce a rich first exhaust stream and a lean second exhaust stream.
摘要:
The disclosed systems and methods include a mold assembly having a malleable mold (4), a moldable blank (2) and a bladder (1) positioned about the moldable blank (2) to transmit an external force applied to the mold assembly uniformly to the moldable blank (2) and hence to the malleable mold (4). The invention further includes a method of replicating a surface by use of the mold assembly. The method may include manipulating the malleable mold (4) to record the image to be replicated. This manipulation may include a physical engagement of the mold with a physical surface to be replicated. Alternatively, an image, e.g., photograph or laser scan of the surface may be transmitted to a computer numerically controlled (“CNC”) system. The CNC system then manipulates the malleable mold (4) to reflect the surface to be replicated. An activated moldable blank, e.g., a blank (2) fabricated from a thermo-forming material, is then positioned over the malleable mold. The bladder (1) is then secured about the moldable blank (2). An external force, such as that induced by placing the mold assembly in a vacuum chamber, is then applied to the mold assembly.
摘要:
The disclosed systems and methods include a mold assembly having a malleable mold (4), a moldable blank (2) and a bladder (1) positioned about the moldable blank (2) to transmit an external force applied to the mold assembly uniformly to the moldable blank (2) and hence to the malleable mold (4). The invention further includes a method of replicating a surface by use of the mold assembly. The method may include manipulating the malleable mold (4) to record the image to be replicated. This manipulation may include a physical engagement of the mold with a physical surface to be replicated. Alternatively, an image, e.g., photograph or laser scan of the surface may be transmitted to a computer numerically controlled (“CNC”) system. The CNC system then manipulates the malleable mold (4) to reflect the surface to be replicated. An activated moldable blank, e.g., a blank (2) fabricated from a thermo-forming material, is then positioned over the malleable mold. The bladder (1) is then secured about the moldable blank (2). An external force, such as that induced by placing the mold assembly in a vacuum chamber, is then applied to the mold assembly.
摘要:
An EGR valve position control method controls a position of an EGR valve according to a pressure change across the valve and a desired EGR valve position. The method calculates a desired EGR valve position and generates one or more duty cycle control terms based on a difference between the desired EGR valve position and an actual EGR valve position. Additionally, the method provides feedforward control based on the pressure change and the desired EGR valve position in order to generate feedforward duty cycle control terms. The method controls the position of the EGR valve based on the duty cycle control terms.
摘要:
A method for reducing the magnitude of a knock retard angle in a vehicle having a quantity of fuel and a system for determining the quantity of fuel. The method determines a previous fuel quantity and a present fuel quantity, determines from said present fuel quantity and said previous fuel quantity whether the quantity of fuel has increased; and decreases the magnitude of the knock retard angle upon determining the quantity of fuel has increased.
摘要:
A power steering load compensation system for an internal combustion engine which employs a pressure sensor to monitor the output pressure of the power steering pump. The pressure sensor provides an input signal to an engine controller, and the engine controller generates an automatic idle speed output signal for controlling the idle speed motor of the engine throttle body. By varying the air flow through the throttle body in accordance with output pressure of the power steering pump, which varies with the pump load placed upon the engine, dips and surges in engine revolutions per minute (RPM) at idle and low speeds may be substantially reduced.
摘要:
A system and method for utilizing fuel as an on-board reductant for selective catalytic reduction of NOx is provided and includes a controller for controlling an engine to produce a lean first exhaust stream and a rich second exhaust stream that are received in respective first and second passageways of a dual path aftertreatment system. The rich second exhaust stream reacts with NOx stored in a NOx storage and reduction catalyst of the second passageway to regenerate this catalyst and generate ammonia. The first exhaust stream and the second exhaust stream having the generated ammonia are combined in a downstream common passageway to form a combined lean exhaust gas stream where the ammonia carried therein is stored or used by an SCR catalyst of the common passageway for NOx reduction. The engine is subsequently controlled to produce a rich first exhaust stream and a lean second exhaust stream.
摘要:
The present invention overcomes these problems by providing an oxygen sensor located in the exhaust stream of an internal combustion engine, a load sensing device which generates a signal indicative of an internal combustion engine load, a central processing unit which calculates a running average of the oxygen content in the exhaust stream indicated by the oxygen sensor and a fuel injection device which supplies fuel to the combustion air in response to the central processing unit. The central processing unit uses the running average of the oxygen content in the exhaust stream, in lieu of the instantaneous oxygen content, to modify the fuel equation for determining the proper air fuel mix when transitioning from closed to open loop operation. The resulting air fuel mixture thus reflects the average oxygen value in the exhaust over a period of time. This average serves to cancel out the extreme surplus and deficiency of oxygen in the exhaust stream due to dithering.