Abstract: Valve timing is held to a position close to a target value as much as possible while suppressing control errors of valve timing even though a crankshaft rotates in reverse. In an internal combustion engine which controls the valve timing by a variable valve timing mechanism (an electric VTC) driven by an electric motor, an intake valve timing is controlled after an output of an engine stop command such that: when the engine rotates in a forward direction, a real valve timing (a VTC real angle ?r) detected by a sensor is converged to a target valve timing (a VTC target angle ?trg) advanced for the time of start; and when the engine rotates in a reverse direction, a manipulated variable of the electric VTC is set so that the VTC real angle ?r is held to the VTC real angle ?r detected just before the detection of the reverse rotation.

Abstract: A control unit for a variable valve timing mechanism for changing a cam phase by an actuator corrects the operation amount of the actuator immediately after an engine is started based on at least an engine rotation angle and a cam phase angle in an engine stop state.

Abstract: The present invention relates to variable valve timing control device and control method, which change valve timing of an internal combustion engine. An operation amount for controlling the valve timing is computed, and an operation amount computed at position detection timing of a valve timing control system is divided and output until next position detection timing.

Abstract: A control unit for a variable valve timing mechanism for changing a cam phase by an electric actuator determines an influence on the operation of the variable valve timing mechanism based on the engine operating conditions. Then, based on the determination result, the control unit reduces the operation amount of the electric actuator in a predetermined range of the rotation angle of a camshaft.

Abstract: Even when a crankshaft reversely rotates, a rotation phase of a camshaft can be accurately detected. A motor shaft rotation angle, a crankshaft forward rotation angle, a crankshaft reverse rotation angle, a final crankshaft rotation angle, a sprocket rotation angle of an electric VTC where a sprocket rotates at ½ rotation speed of the crankshaft and a stator of an electric motor are integrally rotated, a motor shaft rotation angle changing amount during a control period, a sprocket rotation angle changing amount, a motor shaft rotation angle changing amount, an intake camshaft rotation angle changing amount, and a current real rotation angle of the intake camshaft are calculated sequentially, and the VTC manipulated variable is computed so that the VTC real angle follows a VTC target angle.

Abstract: In a control apparatus for a variable valve mechanism that varies a valve characteristic of an engine valve, in a saturated state in which a calculated manipulated variable of the variable valve mechanism exceeds an outputtable manipulated variable, convergence to a desired position is achieved while suppressing a response delay and an overshoot. If a feedforward manipulated variable calculated according to a reference response exceeds an outputtable limit manipulated variable, a saturating amount (feedforward manipulated variable—limit manipulated variable) is integrated. Upon completion of the integration, the feedforward manipulated variable is corrected based on an FF manipulated variable correction amount, and the integrated value of saturating amount is replaced by a value obtained by subtracting the FF manipulated variable correction amount each time a correction is made.

Abstract: A control unit for a variable valve timing mechanism for changing a cam phase by an actuator corrects the operation amount of the actuator immediately after an engine is started based on at least an engine rotation angle and a cam phase angle in an engine stop state.

Abstract: A control unit for a variable valve timing mechanism for changing a cam phase by an electric actuator determines an influence on the operation of the variable valve timing mechanism based on the engine operating conditions. Then, based on the determination result, the control unit reduces the operation amount of the electric actuator in a predetermined range of the rotation angle of a camshaft.

Abstract: Valve timing is held to a position close to a target value as much as possible while suppressing control errors of valve timing even though a crankshaft rotates in reverse. In an internal combustion engine which controls the valve timing by a variable valve timing mechanism (an electric VTC) driven by an electric motor, an intake valve timing is controlled after an output of an engine stop command such that: when the engine rotates in a forward direction, a real valve timing (a VTC real angle ?r) detected by a sensor is converged to a target valve timing (a VTC target angle ?trg) advanced for the time of start; and when the engine rotates in a reverse direction, a manipulated variable of the electric VTC is set so that the VTC real angle ?r is held to the VTC real angle ?r detected just before the detection of the reverse rotation.

Abstract: Even when a crankshaft reversely rotates, a rotation phase of a camshaft can be accurately detected. A motor shaft rotation angle, a crankshaft forward rotation angle, a crankshaft reverse rotation angle, a final crankshaft rotation angle, a sprocket rotation angle of an electric VTC where a sprocket rotates at ½ rotation speed of the crankshaft and a stator of an electric motor are integrally rotated, a motor shaft rotation angle changing amount during a control period, a sprocket rotation angle changing amount, a motor shaft rotation angle changing amount, an intake camshaft rotation angle changing amount, and a current real rotation angle of the intake camshaft are calculated sequentially, and the VTC manipulated variable is computed so that the VTC real angle follows a VTC target angle.

Abstract: The application provides a control apparatus of a variable valve timing mechanism capable of converging valve timing to a target value with good responsiveness as well as with high accuracy when an engine starts. In the state where the engine starts, the variable valve timing mechanism is driven to a target value at the engine start by a second manipulated variable corresponding to a maximum variation speed of valve timing. Valve timing is estimate in the state where the variable valve timing mechanism is driven by the second manipulated variable, and when the estimated valve timing reaches the target value, a manipulated variable is switched from the second manipulated variable to a first manipulated variable which is a feedforward manipulated variable or to the first manipulated variable which is a value obtained by adding the feedforward manipulated variable and a feedback manipulated variable.

Abstract: The application provides a control apparatus of a variable valve timing mechanism capable of converging valve timing to a target value with good responsiveness as well as with high accuracy when an engine starts. In the state where the engine starts, the variable valve timing mechanism is driven to a target value at the engine start by a second manipulated variable corresponding to a maximum variation speed of valve timing. Valve timing is estimate in the state where the variable valve timing mechanism is driven by the second manipulated variable, and when the estimated valve timing reaches the target value, a manipulated variable is switched from the second manipulated variable to a first manipulated variable which is a feedforward manipulated variable or to the first manipulated variable which is a value obtained by adding the feedforward manipulated variable and a feedback manipulated variable.

Abstract: In an engine provided with a valve lift amount variable mechanism and a center phase variable mechanism for an intake valve, a region between a region where a flow rate of an intake air passing through the intake valve reaches a sonic speed and a region where an intake air amount does not substantially change relative to a change in an opening area of the intake valve is made to be a learning region. Then, in order to resolve an error in intake air amount in the learning region, a correction value for correcting control process of the valve lift amount variable mechanism is learned. When the learning of the correction value is converged, the learning correction value is corrected with an occupied rate of the valve lift amount variable mechanism in the influence ratio between influences on the two mechanisms in relation to the error.

Abstract: In an engine provided with a valve lift amount variable mechanism and a center phase variable mechanism for an intake valve, a region between a region where a flow rate of an intake air passing through the intake valve reaches a sonic speed and a region where an intake air amount does not substantially change relative to a change in an opening area of the intake valve is made to be a learning region. Then, in order to resolve an error in intake air amount in the learning region, a correction value for correcting control process of the valve lift amount variable mechanism is learned. When the learning of the correction value is converged, the learning correction value is corrected with an occupied rate of the valve lift amount variable mechanism in the influence ratio between influences on the two mechanisms in relation to the error.