Gm Global Technolgoy Operations, Inc.

Other

Richard Stephen Davis

Glen R MacFarlane

Jordan R Lee

Ko-Jen Wu

Paul M Najt

Edward J Keating

Cherian A Idicheria

Ronald J Herrin

Gary J Patterson

A multi-cylinder engine includes first and second subsets of cylinders. A dedicated-cylinder exhaust gas recirculation (EGR) system is associated with the second subset of cylinders. A plasma ignition system is disposed in the second subset of cylinders. A controller operates the plasma ignition system to control the plasma igniters to execute plasma discharges in the second subset of cylinders to generate residual exhaust gas, which is recirculated through the dedicated-cylinder EGR system to the intake air system for introduction into intake air.

Internal combustion engine employing a dedicated-cylinder EGR system

A control system for an engine includes a spark module and a fuel module. The spark module advances spark timing of a cylinder R degrees past a spark limit for N consecutive cylinder firing events, and retards spark timing of the cylinder past the spark limit for M consecutive cylinder firing events after the N consecutive cylinder firing events. The fuel module supplies a rich fuel-air charge to the cylinder for the M consecutive cylinder firing events. According to the system, R is a real number greater than zero, N and M are integers greater than zero, and the spark limit is a control value used to limit an amount of spark advance to prevent spark-knock. A method for controlling an engine is also provided.

Control system and method for preventing stochastic pre-ignition in an engine

A system includes a sampling module and a map generating module. The sampling module receives a first mapping of thermal efficiency of a spark-ignition engine generated based on operation of the spark-ignition engine with a dynamometer. A combustion chamber of the spark-ignition engine has a first compression ratio. The map generating module generates a second mapping of the thermal efficiency of the spark-ignition engine based on the first mapping and the combustion chamber having a second compression ratio. The second compression ratio is different than the first compression ratio.

Compression ratio determination and control systems and methods

An engine assembly includes an engine structure including an engine block defining a cylinder bore and a cylinder head, a piston located in the cylinder bore, and a camshaft assembly. The piston, cylinder head, and cylinder bore cooperate to define a combustion chamber including first and second longitudinal end surfaces defined by the cylinder head and the piston. A first protrusion may extend longitudinally from one of the first and second longitudinal end surfaces and radially inward from a circumference of the combustion chamber to a location between a first intake port and a first exhaust port in communication with the combustion chamber. The camshaft assembly may include a first intake lobe that opens a first intake valve and a second intake lobe that opens a second intake valve. The first intake lobe may be rotationally offset from the second intake lobe in a rotational direction of the camshaft assembly.

Engine combustion chamber features for camshaft with differential valve lift

An engine assembly may include an engine structure, first and second intake valves, and a camshaft assembly. The engine structure may define a combustion chamber, a first intake port in communication with the combustion chamber and directing intake air flow toward a central region of the combustion chamber, and a second intake port in communication with the combustion chamber. The first intake valve may open and close the first intake port and the second intake valve may open and close the second intake port. The camshaft assembly may include a first intake lobe that opens the first intake valve and a second intake lobe that opens the second intake valve. The first intake lobe may be rotationally offset from the second intake lobe in a rotational direction of the camshaft assembly.

Engine intake port arrangement for camshaft with differential valve lift

A camshaft assembly may include a first shaft, a second shaft, a first lobe and a second lobe. The second shaft may be coaxial with and rotatable relative to the first shaft. The first lobe may be fixed for rotation with the first shaft and adapted to open a first valve in communication with an engine combustion chamber. The first lobe may define a first valve opening region having a first angular extent. The second lobe may be fixed for rotation with the second shaft and adapted to open a second valve in communication with the engine combustion chamber. The second lobe may define a second valve opening region having a second angular extent greater than the first angular extent.

Engine having concentric camshaft with differential valve lift

A cam phaser assembly may include a drive plate assembly, a cavity plate, and a driven plate assembly. The drive plate assembly may include a drive plate and a first vane fixed for rotation with the drive plate. The cavity plate may be rotationally driven by the drive plate and may define first and second chambers. The first vane may extend into the first chamber. The driven plate assembly may be rotationally driven by the drive plate assembly and may include a driven plate and a second vane fixed for rotation with the driven plate that extends into the second chamber.

Dual-equal cam phasing with variable overlap

A vehicle may include a drive axle, an engine assembly, a coupling device, and an engine load management system. The engine assembly may include a valvetrain including a fixed-lobe camshaft and intake and exhaust valves supported by the engine assembly. The fixed-lobe camshaft may include a first lobe engaged with the intake valve to open the intake valve and a second lobe engaged with the exhaust valve to open the exhaust valve. The first and second lobes may be fixed relative to one another to define a constant valve overlap condition that provides for opening of the intake valve before the exhaust valve is fully closed, creating an engine operating condition that results in combustion instability below an engine load limit. The engine load management system may be in communication with the engine to prevent engine operation below the engine load limit.

High overlap camshaft for improved engine efficiency

A system is disclosed for diagnosing faulty check valve operation in an internal combusiton engine having a back flow preventing check valve positioned in each intake air passage leading to an engine cylinder. The system measures the pressure in the engine air induction system, upstream of each check valve and downstream from an air intake throttle valve. The system produces an indication of faulty check valve operation, when an abnormal fluctuation in the measured pressure is detected. Preferably, the diagnostic function is performed when the engine operates in a defined mode, at idle speeds with light engine loading, where the pressure differential appearing across each check valve is essentially maximized. The engine cylinder associated with a faulty check valve is identified based upon the sensed rotational position of the engine when an abnormal fluctuation in pressure is detected.

Diagnostic system for detecting faults in engine air intake check valves

An intermittent bypass system comprises an intake conduit including an intake passage leading to a cylinder in an engine and an intake controller connected to the intake passage adjacent to the cylinder. The intake controller enables, during different portions of the engine cycle, fluid flow from the intake passage into the cylinder, fluid back-flow from the cylinder into the intake passage, and obstruction of fluid flow between the intake passage and the cylinder. A check valve is located in the intake passage upstream of the intake controller with the check valve allowing fluid flow toward the cylinder and obstructing fluid back-flow in the reverse direction. A bypass port is located on the intake passage to provide a flow path to a downstream portion defined by the portion of the intake passage between the check valve and intake controller. A control valve is connected between a secondary fluid source and the bypass port enabling communication between the secondary fluid source and downstream portion during a portion of the engine cycle when the check valve is open. The control valve obstructs the communication during a portion of the engine cycle when the check valve is closed.

Intermittent bypass system for a check valve

An internal combustion engine has a stator passage leading to a cylinder. An intake poppet valve is disposed between the cylinder and stator passage, and a rotary valve adjoins the opposite end of the stator passage. The rotary valve has a rotor with an elongated tapered rotor passage partially in registration with the stator passage. The rotor is driven by the crankshaft and is adjustable in phase to vary the time of opening and closing of the rotary valve, and is axially shiftable to vary the valve opening duration. A control system responsive to engine speed and load independently varies the rotary valve phase and duration for optimum engine operation.

Rotary valve and system for duration and phase control

A pressure relief system is for an engine having an intake passage leading to a cylinder, a check valve in the intake passage to allow fluid flow toward the cylinder and obstruct fluid back-flow in the reverse direction, and a bypass port located on the intake passage so that the bypass port communicates with a downstream portion defined by the portion of the intake passage between the cylinder and check valve. The pressure relief system comprises a pressure relief passage connected between the bypass port and a reservoir enabling communication between the reservoir and downstream portion. A pressure-sensitive valve is connected to the pressure relief passage. The pressure-sensitive valve allows the communication if the pressure in the downstream portion exceeds a reference pressure by a predetermined amount, and obstructs the communication if the pressure in the downstream portion does not exceed the reference pressure by the predetermined amount.

Pressure relief system for a check valve

An intake port pressure control system comprises an intake passage leading to a cylinder in an engine, and a check valve in the intake passage to allow fluid flow toward the cylinder and obstruct fluid back-flow in the reverse direction. A bypass port is located on the intake passage so that the bypass port communicates with a trapped volume defined by the portion of the intake passage between the check valve and intake valve. The intake port pressure control system further comprises a control valve having an outlet passage, a secondary passage, and an actuator enabling communication between the outlet passage and secondary passage. The actuator further enables active adjustment of the flow area of the flowpath between the secondary passage and outlet passage throughout a range of engine operating conditions. The outlet passage is connected to the bypass port, and the secondary passage is connected to a secondary air source. The control valve enables a controlled air flow therein between the secondary air source and the trapped volume when the intake valve is closed.

Intake port pressure control system for engine induction system

An intake reservoir system is for an engine having an intake passage leading to a cylinder, and a check valve in the intake passage to allow fluid flow toward the cylinder and obstruct fluid back-flow in the reverse direction. A bypass port is located on the intake passage so that the bypass port communicates with a trapped volume defined by the portion of the intake passage between the check valve and cylinder. The intake reservoir system comprises an inflower for enabling fluid to flow into the trapped volume when the pressure therein is at least equal to the pressure upstream of the check valve. The intake reservoir system further comprises a reservoir cavity, a port passage connected between the reservoir cavity and bypass port enabling communication between the reservoir cavity and trapped volume, and a volume controller enabling adjustment of the volume of the reservoir cavity.

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Lake Orion, MI, United States of America

Richard Stephen Davis