Abstract: A valve timing control system for accelerating activation of a catalytic converter in an internal combustion engine in a cold starting operation mode. The system includes actuators (15, 16) coupled to cam shafts (15C, 16C), hydraulic pressure supply units (19, 20) for driving the actuators (15; 16), and a controller (21A) for controlling a hydraulic pressure for the actuators (15, 16) in dependence on engine operation states to change phase of the cam shafts (15C; 16C) relative to a crank shaft. The actuator (15; 16) includes a locking mechanism (155, 157) for setting the relative phase to a lock-up position, and an unlocking mechanism (156) for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller (21A) sets the relative phase to the lock-up position in a starting operation, while controlling the relative phase to be retarded in an engine state succeeding to the starting operation.

Abstract: A valve timing control system for an internal combustion engine for preventing dispersion of a control amount and unexpected unlocking of a lock pin is provided. The valve timing control system is provided with actuators 15 and 16 connected to cam shafts 15C and 16C, hydraulic pressure supply units 19 and 20 for driving the actuators, and a controller 21A for controlling a hydraulic pressure for the actuators depending on operating states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position and unlocking mechanisms for unlocking the locking mechanism in response to a predetermined hydraulic pressure, and the controller restricts a control of valve timing within a predetermined range of said lockup position in the locking mechanism.

Abstract: A valve timing control system for an internal combustion engine for preventing dispersion of a control amount and unexpected release of a lock pin is provided. The valve timing control system is provided with actuators 15 and 16 connected to cam shafts 15C and 16C, hydraulic pressure supply units 19 and 20 for driving the actuators, and a controller 21A for controlling a hydraulic pressure for the actuators in dependence on engine operation states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position, and an unlocking mechanism for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller makes a limit of control range small when the controller drives the locking mechanism to control the relative phase within a predetermined range of the lock-up position.

Abstract: A valve timing control system for an internal combustion engine for preventing hitching of a lock pin of an actuator at the time of changing a cam angle is provided. The valve timing control system is provided with actuators 15 and 16 connected to cam shafts 15C and 16C, hydraulic pressure supply units 19 and 20 for driving the actuators, and a controller 21A for controlling a hydraulic pressure for the actuators in dependence on engine operation states while changing a relative phase of the cam shafts relative to crank shafts. The actuator includes a locking mechanism for setting the relative phase to a lock-up position, and an unlocking mechanism for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller executes a releasing operation of the locking mechanism if the lock-up position in the locking mechanism changes from inside a predetermined range to outside the predetermined range.

Abstract: A valve timing control system for accelerating activation of a catalytic converter in an internal combustion engine in a cold starting operation mode while enhancing control accuracy by learning a reference position of a cam angle. The system includes actuators (15; 16) coupled to cam shafts (15C; 16C), respectively, hydraulic pressure supply means (19; 20) for driving the actuators (15; 16), and a controller (21A) for controlling hydraulic pressure fed to the actuators (15; 16) in dependence on engine operation states to change phases of the cam shafts (15C; 16C) relative to a crank shaft (13C). The controller (21A) is so designed as to set a valve timing to a most advanced position or alternatively to a most retarded position in a cold-state idling operation mode for the purpose of learning a reference position.

Abstract: A valve timing control apparatus for an internal combustion engine is capable of ensuring good response within a control range, stability outside the control range, and durability without increasing the capacity of electric power for a drive circuit and an OCV coil. The valve timing control apparatus includes an intake vale 31, an exhaust valve 32, an engine operating condition detecting section (3, 11, 14), a target valve timing calculating section 21, variable valve timing mechanisms 15, 16, an actual valve timing detecting section (14, 17, 18), a control amount calculating section 21 for calculating a control amount based on target valve timing, actual valve timing and engine operating conditions, and an actual valve timing control section (19, 20) for outputting the control amount as an output control amount to the variable valve timing mechanisms.

Abstract: There is disclosed a valve timing controller having excellent response and used with an internal combustion engine. The controller performs a corrective control operation according to the oil pressure control characteristics of the actually mounted valve. The valve timing controller comprises an intake cam, an exhaust cam, an actuator for varying the phase of rotation of one of the cams relative to the crankshaft of the engine, an oil pressure control valve for applying oil pressure on the actuator, and a control means for controlling the valve timing by controlling the oil pressure output from the oil pressure control valve. The oil pressure output is controlled by controlling the current through the solenoid in the oil pressure control valve. The two cams are driven by the crankshaft of the engine. The intake cam opens and closes the intake valve. The exhaust cam opens and closes the exhaust valve.

Abstract: A valve timing control system for an internal combustion engine for improving engine starting performance by controlling an actuator to a lock-up position upon stopping of the engine and fixing the actuator positively at the lock-up position by a locking mechanism. The control system (21A) includes a power supply interruption detecting means (215) for detecting a time point when electric power supply is interrupted, a desired valve timing setting means (213A) for setting a desired valve timing (VTo) on the basis of engine operation state (D), and an actual valve timing control means (214A) for driving the actuator (15, 16) so that the actual valve timing (VTA) coincides with the desired valve timing (VTo).

Abstract: A valve timing control system for accelerating activation of a catalytic converter in an internal combustion engine in a cold starting operation mode. The system includes actuators (15, 16) coupled to cam shafts (15C, 16C), hydraulic pressure supply units (19, 20) for driving the actuators (15; 16), and a controller (21A) for controlling a hydraulic pressure for the actuators (15, 16) in dependence on engine operation states to change phase of the cam shafts (15C; 16C) relative to a crank shaft. The actuator (15; 16) includes a locking mechanism (155, 157) for setting the relative phase to a lock-up position, and an unlocking mechanism (156) for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller (21A) sets the relative phase to the lock-up position in a starting operation, while controlling the relative phase to be advanced in an engine state succeeding to the starting operation.

Abstract: A valve timing control system for accelerating activation of a catalytic converter in an internal combustion engine in a cold starting operation mode. The system includes actuators (15, 16) coupled to cam shafts (15C, 16C), hydraulic pressure supply units (19, 20) for driving the actuators (15; 16), and a controller (21A) for controlling a hydraulic pressure for the actuators (15, 16) in dependence on engine operation states to change phase of the cam shafts (15C; 16C) relative to a crank shaft. The actuator (15; 16) includes a locking mechanism (155, 157) for setting the relative phase to a lock-up position, and an unlocking mechanism (156) for releasing the locking mechanism in response to a predetermined hydraulic pressure. The controller (21A) sets the relative phase to the lock-up position in a starting operation, while controlling the relative phase to be retarded in an engine state succeeding to the starting operation.

Abstract: A valve timing control apparatus for internal combustion engines, capable of obtaining a stable responsibility, and correcting a scatter of the characteristics of the apparatus and the variation thereof occurring with the lapse of time is provided.

Abstract: A valve timing control apparatus for internal combustion engines, capable of obtaining a stable responsibility, and correcting a scatter of the characteristics of the apparatus and the variation thereof occurring with the lapse of time is provided.

Abstract: There is disclosed a valve timing controller having excellent response and used with an internal combustion engine. The controller performs a corrective control operation according to the oil pressure control characteristics of the actually mounted valve. The valve timing controller comprises an intake cam, an exhaust cam, an actuator for varying the phase of rotation of one of the cams relative to the crankshaft of the engine, an oil pressure control valve for applying oil pressure on the actuator, and a control means for controlling the valve timing by controlling the oil pressure output from the oil pressure control valve. The oil pressure output is controlled by controlling the current through the solenoid in the oil pressure control valve. The two cams are driven by the crankshaft of the engine. The intake cam opens and closes the intake valve. The exhaust cam opens and closes the exhaust valve.

Abstract: A valve timing control system for an internal combustion engine is arranged such that a plurality of valve timing control means can be actuated without degrading or impairing the responsivity of the other valve timing control means or mechanism(s), whereby the responsivity of not only the valve timing control means actuated but also the other valve timing control means not actuated can be ensured.

Abstract: A control system for an internal combustion engine which can judge and detect a failure of a valve, timing changing unit regardless of operating conditions. The system includes a second storage unit 9 for storing the detection value of an actual valve timing detection unit 2 when the target advance angle set by a target advance angle setting device 3 is a predetermined value and updating the storage value, a storage value update inhibiting unit 10 for inhibiting the update of the storage value of the second storage unit when a change in the storage value updated by a first storage unit 4 is larger than a predetermined value, and failure judging unit 8A for judging a failure of the valve timing changing unit based on the target advance angle set, the detection value of the actual valve timing detection unit and the storage value of the second storage unit.

Abstract: A valve timing control system for an internal combustion engine, comprising a required advance amount calculating section for calculating a required advance amount on the basis of operating condition of the engine, a valve timing control section for calculating a valve timing control variable on the basis of an obtained advance amount and the required advance amount calculated by the required advance amount calculating section, and a time period measuring section for measuring an elapsed time after the start of the engine. The required advance amount calculating section makes a calculation so that the required advance amount assumes a value smaller than that in an normal state until the time period measuring section measures a predetermined period of time. Hence, exhaust gas clarification immediately after the engine start, fuel consumption and drivability can be improved.

Abstract: An internal-combustion engine control system is able to suppress the occurrence of problems such as changes in air-fuel ratio. The internal-combustion engine control system is equipped with intake pressure detecting means for detecting intake pressure in the internal-combustion engine; operating state detecting means for detecting the operating state of the internal-combustion engine; and controlling means for controlling the operation of the internal-combustion engine according to the operating state of the internal-combustion engine; wherein the controlling means corrects the amount of the fuel injection according to a differential pressure between the intake pressure in a steady operation mode of the internal-combustion engine and an intake pressure detected by the intake pressure detecting means.

Abstract: A control system for an internal combustion engine which can judge and detect a failure of a valve timing changing unit regardless of operating conditions. The system includes a second storage unit 9 for storing the detection value of an actual valve timing detection unit 2 when the target advance angle set by a target advance angle setting device 3 is a predetermined value and updating the storage value, a storage value update inhibiting unit 10 for inhibiting the update of the storage value of the second storage unit when a change in the storage value updated by a first storage unit 4 is larger than a predetermined value, and failure judging unit 8A for judging a failure of the valve timing changing unit based on the target advance angle set, the detection value of the actual valve timing detection unit and the storage value of the second storage unit.

Abstract: A control system for an internal combustion engine which can judge and detect a failure of a valve timing changing unit regardless of operating conditions. The system includes a second storage unit 9 for storing the detection value of an actual valve timing detection unit 2 when the target advance angle set by a target advance angle setting device 3 is a predetermined value and updating the storage value, a storage value update inhibiting unit 10 for inhibiting the update of the storage value of the second storage unit when a change in the storage value updated by a first storage unit 4 is larger than a predetermined value, and failure judging unit 8A for judging a failure of the valve timing changing unit based on the target advance angle set, the detection value of the actual valve timing detection unit and the storage value of the second storage unit.

Abstract: A control system for an internal combustion engine which can judge and detect a fail of a valve timing changing unit regardless of operation condition.