A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

The present invention relates to a rocker arm (16) for an internal combustion engine (12). The rocker arm (16) comprises a cavity (41) with a cavity wall (42) at least partially accommodating a lash adjustment piston (44) for hydraulic lash adjustment. The rocker arm (16) further comprises a lash stop surface (46). At least a portion of the lash adjustment piston (44) is adapted to abut the lash stop surface (46) during at least one operating condition of the rocker arm (16). The cavity (41) comprises a lash adjustment chamber (50) at least partially delimited by the lash adjustment piston (44). The rocker arm (16) further comprising a control fluid conduit (52) and a valve assembly (54) located between the lash adjustment chamber (50) and the control fluid conduit (52), as seen in an intended direction of flow from the control fluid conduit (52) to the lash adjustment chamber (50).

A controller increases an actual oil pressure up to a transient oil pressure (an actuating oil pressure) and then supplies oil adjusted to have the transient oil pressure (the actuating oil pressure) to valve stopping mechanisms to actuate the valve stopping mechanisms. The controller, when actuating the valve stopping mechanisms, starts increase in an intake filling amount when the actual oil pressure increases up to a predetermined determination value set at the transient oil pressure (the actuating oil pressure) or lower.

A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

A control device for an onboard engine is configured to control the oil discharge pressure of an oil pump and execute, when determining that there may be an abnormality in the control of the oil discharge pressure, a change process that increases the target discharge pressure to a value that is greater than that before it is determined that there may be an abnormality in the control. When a discharge pressure sensor value in a situation in which the discharge pressure is being controlled based on the target discharge pressure increased through execution of the change process does not become greater than or equal to a discharge pressure threshold, the control device sets an upper limit for the engine rotation speed and increases the upper limit as the discharge pressure sensor value increases.

Various embodiments include a method for identifying valve stroke phase differences during operation comprising: measuring dynamic pressure oscillations in the air intake tract; generating a corresponding signal; acquiring a crankshaft phase angle; acquiring the phase position and the amplitude of a signal frequency of the oscillations based on the pressure oscillation using discrete Fourier transformation; acquiring a line of an equal phase position and of equal amplitude of the signal frequency reflecting the inlet and the outlet stroke phase difference using reference lines; acquiring a common intersection point of a line of equal phase position and a line of equal amplitude by projection into a common plane; and determining the stroke phase differences and from the common intersection point.

Various embodiments include a method for identifying an inlet and an outlet valve stroke phase difference comprising: measuring pressure oscillations during operation; generating a corresponding signal; determining a corresponding crankshaft phase angle; applying a discrete Fourier transformation to the pressure signal to determine amplitudes of selected frequencies in relation to the crankshaft phase angle; determining lines of equal amplitudes of the frequencies based on the amplitudes depending on the phase differences using reference lines; determining an intersection of the lines by projection into a common plane; and determining the inlet valve stroke phase difference and the outlet valve stroke phase difference from the determined common intersection point of the lines of equal amplitudes of the selected signal frequencies.

An oil supply control device includes: a memory which stores first master data constituted by predetermined control value; a hydraulic controller which outputs the control value to an adjusting device to cause a hydraulic pressure to coincide with a target hydraulic pressure; and a determination portion which determines whether or not a first difference between an output control value and the control value of the first master data lies within a predetermined allowable range, wherein the hydraulic controller starts to control the adjusting device with use of the control value of the first master data, when the first difference lies within the allowable range, and starts to control the adjusting device with use of the control value of second master data, when the first difference does not lie within the allowable range, the control value of the second master data causing the first difference to lie within the allowable range.

An apparatus includes a valve and an actuator. The valve has a portion movably disposed within a valve pocket defined by a cylinder head of an engine. The valve is configured to move relative to the cylinder head a distance between a closed position and an opened position. The portion of the valve defines a flow opening that is in fluid communication with a cylinder of an engine when the valve is in the opened position. The actuator is configured to selectively vary the distance between the closed position and the opened position.

A modified rocker assembly having an offset end is designed for engine heads having an obstruction preventing use of a symmetric switching rocker arm. The modified rocker assembly has an obstructed side and a non-obstructed side and has an outer structure with a first end, and an inner rocker structure fitting within the outer structure, the inner structure also having a first end. The modified rocker assembly has an axle pivotally connecting the first ends of inner structure to the outer structure, such that the inner structure pivots within the outer structure around the axle. At least one torsion spring on one side of the axle rotationally biases the inner structure relative to the outer structure. The outer structure is offset on the obstructed side as it extends from the second end toward the first end, creating the first offset portion to provide additional clearance on the obstructed side.