A controller for an internal combustion engine includes a processing circuit configured to execute a calculating process that calculates a returned air amount and an operating process that operates a fuel injection valve so that an air-fuel ratio of a mixture that is burned in a combustion chamber is controlled to a target value. The operating process includes under a condition in which the returned air amount is increased, having the fuel injection valve inject fuel increased in amount from a constant fuel amount, which is an amount of fuel injected when the returned air amount is unchanged, and under a condition in which the returned air amount is decreased, having the fuel injection valve inject fuel decreased in amount from the constant fuel amount.

A hydraulic fluid system for a variable valve train system is provided that allows hydraulic fluid flow from a high pressure chamber to a medium pressure chamber during a higher pressure phase after a control valve closes. The hydraulic fluid system includes a housing defining (a) the middle pressure chamber which is connected to a hydraulic fluid supply, and (b) the high pressure chamber which contains hydraulic fluid that is pressurized by a pump piston assembly configured to engage a rotating cam. A control valve selectively provides a first flowpath for hydraulic fluid between the middle pressure chamber and the high pressure chamber. A bypass valve selectively provides a second flowpath for hydraulic fluid between the middle pressure chamber and the high pressure chamber based on a pressure of the hydraulic fluid in the high pressure chamber.

A camless valve control system for an internal combustion engine, includes a hydraulic pump, with a rotating shaft timed to the operation of the engine and a hydraulic actuator configured to selectively open and close one of an intake valve and an exhaust valve of the engine. The hydraulic actuator includes a rotating cylindrical pump body and one or more control rings with holes channeling the flow of the hydraulic control fluid to affect the selective opening and closing of the one of the intake value and the exhaust valve. The pump body includes a cylindrical center portion configured to receive torque from the hydraulic pump and at least one channel providing a flow of hydraulic control fluid from the pump.

A controller for an internal combustion engine includes a processing circuit configured to execute a calculating process that calculates a returned air amount and an operating process that operates a fuel injection valve so that an air-fuel ratio of a mixture that is burned in a combustion chamber is controlled to a target value. The operating process includes under a condition in which the returned air amount is increased, having the fuel injection valve inject fuel increased in amount from a constant fuel amount, which is an amount of fuel injected when the returned air amount is unchanged, and under a condition in which the returned air amount is decreased, having the fuel injection valve inject fuel decreased in amount from the constant fuel amount.

An early exhaust valve opening (EEVO) module increases a no-load engine speed so an engine can smoothly transition to driving a load when necessary. The EEVO module includes a drive piston engaging an injector rocker and a driven piston engaging an exhaust rocker. The pistons are fluidly connected by a activation fluid passage so that the drive piston compresses air in the passage when an injector cam rotates the injector rocker and causes movement of the driven gear and the exhaust rocker to open an exhaust valve to release exhaust energy during a piston expansion stroke to limit the energy transferred to a crankshaft. A low pressure timing valve may drain pressurized fluid from the passage during an initial portion of the movement of the drive piston so driven piston does not move to open the exhaust valve until a desired amount of energy has been transferred to the crankshaft.

Disclosed is a procedure to minimize NOx during varying engine loads in a 4-stroke diesel engine including at least one cylinder with a cylinder head, first piston on a connecting rod, one actuator mounted on the cylinder head and one of the actuator operated second piston lockable via a hydraulic circuit in various positions in a combustion chamber. The second piston, at the latest during the current compression stroke is actuated by the actuator and locked in the combustion chamber, where it by the first piston introduced air is compressed in a predetermined compression ratio to meet an existing engine load wherein the free operated inlet valve is brought to close the inlet stroke at a piston position where the volume of the combustion air as introduced at the end of the compression stroke gives the predetermined compression ratio and that the injector injects the stated amount of fuel.

A control apparatus for an internal combustion engine includes an electronic control unit that is configured to perform an operation of making a lift amount of a specific valve corresponding to one of either intake ports or exhaust ports for a specific cylinder in which an amount of condensate water produced in the port or flowing into the port is larger than in the other cylinders when the engine is stopped, in a case where production of condensate water in the ports or inflow of condensate water into the ports is predicted.

A control device for an internal combustion engine includes a throttle valve actuator and circuitry. The circuitry is configured to calculate, based on a target intake air amount, a target recirculated amount of recirculated exhaust gas that is recirculated to an intake passage through an exhaust gas recirculation device, calculate a corrected target recirculated amount based on the target recirculated amount and an exhaust gas recirculated amount change delay in a change in a recirculated amount of the recirculated exhaust gas, calculate a target intake pressure based on the target intake air amount and the corrected target recirculated amount, calculate a target opening degree of the throttle valve based on the target intake air amount and the target intake pressure, and control the throttle valve actuator to drive the throttle valve such that an opening degree of the throttle valve is to be equal to the target opening degree.

An oil supply control device includes: an adjusting device which adjusts an oil discharge amount according to an input control value to adjust a hydraulic pressure; a hydraulic controller which outputs the control value to the adjusting device; a memory which stores a first initial control value corresponding to a first target hydraulic pressure at which a hydraulic actuating device is not activated, and a second initial control value corresponding to a second target hydraulic pressure at which the hydraulic actuating device is activated; and a determination portion which compares oil initial characteristics represented by the first and second initial control values with oil characteristics represented by first and second control values, to perform oil determination as to whether or not a viscosity of the oil has changed, the first control value being input before increase of the hydraulic pressure, the second control value being input after increase.

A hydraulic fluid system for a variable valve train system is provided that allows hydraulic fluid flow from a high pressure chamber to a medium pressure chamber during a higher pressure phase after a control valve closes. The hydraulic fluid system includes a housing defining (a) the middle pressure chamber which is connected to a hydraulic fluid supply, and (b) the high pressure chamber which contains hydraulic fluid that is pressurized by a pump piston assembly configured to engage a rotating cam. A control valve selectively provides a first flowpath for hydraulic fluid between the middle pressure chamber and the high pressure chamber. A bypass valve selectively provides a second flowpath for hydraulic fluid between the middle pressure chamber and the high pressure chamber based on a pressure of the hydraulic fluid in the high pressure chamber.