Abstract:
An internal-combustion engine includes a three-way, three-position solenoid valve, having an inlet communicating with a pressurized-fluid chamber and with a hydraulic actuator of an intake valve, and two outlets communicating with an actuator of another intake valve of a cylinder and the exhaust channel. The solenoid valve has a first position, in which the inlet communicates with both outlets, a second position, in which the inlet communicates only with the outlet connected to the actuator of the intake valve and a third position, in which the inlet does not communicate with any of the two outlets. During at least part of an active stroke of a tappet, the solenoid valve is kept in the third position to render the first intake valve active. During the active stroke of the tappet, the solenoid valve is never brought into the second position so that the second intake valve always remains closed.
Abstract:
A system and method for determining the oil pressure of an internal combustion engine is disclosed herein. The system and/or method may estimate the oil pressure using the response of two variable camshaft timing actuators having respective phase angle change control signals. Specifically, the signals may be used to determine whether the oil pressure is below a low oil pressure threshold value. The rate of response of the actuators may also be used to determine a current engine oil pressure.
Abstract:
A variable valve timing control apparatus adjusts the rotation phase (VCT phase) of an engine camshaft by selectively supplying oil to an advancement chamber and a retardation chamber, and includes a lock pin which is controlled for being moveable to a first position, in which the rotation phase is adjustable, and a second position, in which the camshaft is locked at a specific rotation phase. When the lock pin is displaced from the first position, oil becomes enabled to pass between the advancement chamber and retardation chamber, to thereby enabling the rotation phase to be changed to the specific rotation phase by supplying oil to an appropriate one of the advancement chamber and a retardation chamber, for initiating locking.
Abstract:
When a hydraulic pressure generation source begins to generate hydraulic pressure, the present invention measures the hydraulic pressure in an oil supply line connected to a hydraulic actuator, and sets a viscosity index value indicating an oil viscosity in accordance with the pace at which the measured hydraulic pressure rises. The viscosity index value is calculated and set so that the slower the pace at which the measured hydraulic pressure rises, the higher the viscosity indicated by the viscosity index value.
Abstract:
Provided is a control apparatus for an internal combustion engine which controls the internal combustion engine in such a manner as to prevent excessive overshoot of an actual phase angle at a time of phase angle feedback control. The control apparatus for an internal combustion engine includes: a unit for detecting an actual phase angle of a camshaft based on a crank angle signal and a cam angle signal; a unit for setting a target phase angle of the camshaft based on an operational state; and a unit for performing phase angle feedback control calculation such that the actual phase angle coincides with the target phase angle, to calculate an amount of operation for the hydraulic pressure control solenoid valve, in which: the phase angle feedback control calculation is started for a first time after a KEY is turned ON with an initial value of an integral term set to a predetermined value; the phase angle feedback control calculation is performed using a control gain obtained by multiplying a control gain at a time of normal control when a control difference is equal to or larger than a preset value during the phase angle feedback control; and the phase angle feedback control calculation is performed using the control gain at the time of normal control when the control difference is smaller than the preset value during the phase angle feedback control.
Abstract:
A method of controlling cylinder valve switching between a first valve condition and a second valve condition for transitioning between combustion modes of an engine. The method includes adjusting timing of a signal to switch between the valve conditions based on an oil degradation condition from an oil sensor, wherein the combustion modes include spark ignition and homogenous charge compression ignition.
Abstract:
Provided is a control apparatus for an internal combustion engine which controls the internal combustion engine in such a manner as to prevent excessive overshoot of an actual phase angle at a time of phase angle feedback control. The control apparatus for an internal combustion engine includes: a unit for detecting an actual phase angle of a camshaft based on a crank angle signal and a cam angle signal; a unit for setting a target phase angle of the camshaft based on an operational state; and a unit for performing phase angle feedback control calculation such that the actual phase angle coincides with the target phase angle, to calculate an amount of operation for the hydraulic pressure control solenoid valve, in which: the phase angle feedback control calculation is started for a first time after a KEY is turned ON with an initial value of an integral term set to a predetermined value; the phase angle feedback control calculation is performed using a control gain obtained by multiplying a control gain at a time of normal control when a control difference is equal to or larger than a preset value during the phase angle feedback control; and the phase angle feedback control calculation is performed using the control gain at the time of normal control when the control difference is smaller than the preset value during the phase angle feedback control.
Abstract:
A valve characteristic changing mechanism is supplied with oil discharged from an electric oil pump in addition to oil discharged from a mechanical oil pump that is driven by an operation of an internal combustion engine. Driving of the electric oil pump is controlled such that a work rate of the electric oil pump increases as a temperature of the oil supplied to the valve characteristic changing mechanism increases, or as a viscosity of the oil is reduced.
Abstract:
A valve characteristic changing mechanism is supplied with oil discharged from an electric oil pump in addition to oil discharged from a mechanical oil pump that is driven by an operation of an internal combustion engine. Driving of the electric oil pump is controlled such that a work rate of the electric oil pump increases as a temperature of the oil supplied to the valve characteristic changing mechanism increases, or as a viscosity of the oil is reduced.
Abstract:
A valve timing control apparatus of an internal combustion engine that includes a biasing device that applies bias force to a camshaft of intake or exhaust valves so as to bring the valve timing of the engine into a predetermined state when the valve timing is in a predetermined range, for example, when the valve timing is on the retard side of the engine start valve timing with which the engine is started is controlled by a controller that controls the valve timing in view of the bias force of the biasing device.