Abstract: A brushless motor of a variable valve mechanism varies a actuation parameter of an intake valve of an engine. A position sensor outputs a pulse signal when the brushless motor rotates. A position counter calculates a counter value by counting edges of the pulse signal. A motor control device obtains a detection value of a motor rotational angle based on the counter value when the motor control device is in a powered state. An engine control device determines that the detection value of the motor rotational angle is displaced from the actual value when the engine control device detects that the engine is operating and the motor control device portion is in a non-powered state.

Abstract: To provide a control apparatus of an engine that improves vehicle drivability by controlling a variable valve mechanism. The control apparatus of an engine prohibits the changing of the valve duration of an intake valve during a stop of an engine.

Abstract: After power supply from a backup power source to a volatile memory is restored from temporary suspension, a remaining data determining section determines whether data of change history remaining in the volatile memory is data that has been stored immediately before the suspension of the power supply. When it is determined that the data remaining in the volatile memory is not the data that has been stored immediately before suspension of the power supply, a reference value learning section moves an actuator to a limit position, assigns the reference value to an initial value, and clears the change history. When suspension of the power supply from the backup power source reoccurs before completion of the reference value learning by the reference value learning section, a control section invalidates the determination of the remaining data determining section and performs the reference value learning, after the power supply is restored.

Abstract: An internal combustion engine includes a valve timing change mechanism that changes the phase of an intake cam, and a lift amount change mechanism that changes lift amount by causing displacement of a control shaft. An electronic control unit performs a coordinated control in which the lift amount change mechanism is operated such that the position of the control shaft that is detected by a position detection sensor becomes the target position, and the valve timing change mechanism is operated according to a control state of the lift amount change mechanism. When a discrepancy between the actual position of the control shaft and the detected position thereof is estimated to be large, coordinated control is forbidden and the valve timing change mechanism is operated based on engine load.

Abstract: An abnormality determination apparatus for an intake amount control mechanism according to the invention includes a control portion which sets an allowable range of an opening amount of a throttle valve which provided in an intake passageway of an internal combustion engine based at least on an index value of an engine operation state, including an operation amount of accelerator, and on a lift working angle of an intake valve, and which determines that an abnormality is present in a state of driving of the throttle valve if an actual opening amount of the throttle valve is outside the allowable range set.

Abstract: An electronic control unit 9 performs a delay control for extending the period from when an engine stop request is made to when the engine is actually stopped. During non-execution of the delay control, the electronic control unit 9 adjusts the opening degree of a throttle valve 38 according to an accelerator pedal depression degree. During the execution of the delay control, the electronic control unit 9 adjusts the opening degree of a throttle valve 38 such that the opening degree becomes less than the opening degree during the non-execution of the delay control.

Abstract: When it is determined that an engine speed NE rapidly decreases (positive outcome at S210), a throttle increase amount TAu and a valve lift increase amount VLu are computed based on a decrease rate NEd of the engine speed NE (S220). Then, a target throttle opening degree TAt of a throttle valve and a target maximum valve lift VLt of an intake valve are increased by using the throttle increase amount TAu and the valve lift increase amount VLu (S230). As a result, a drop in the engine speed during idling is reliably suppressed.

Abstract: An electronic control unit (60) performs maximum position learning by driving an actuator (50) to move a control shaft (340), and learning the position where stopping occurs because the cylinder head (20) contacts with the Hi end stopper (343) as the movable limit position (Hi end) where the maximum lift amount of the intake valve is largest, to correct the cumulative movement of the control shaft (340). The electronic control unit (60) prevents maximum position learning when the engine speed NE is higher Than a prescribed rotational speed NEst.

Abstract: An internal combustion engine includes a valve timing change mechanism that changes the phase of an intake cam, and a lift amount change mechanism that changes lift amount by causing displacement of a control shaft. An electronic control unit performs a coordinated control in which the lift amount change mechanism is operated such that the position of the control shaft that is detected by a position detection sensor becomes the target position, and the valve timing change mechanism is operated according to a control state of the lift amount change mechanism. When a discrepancy between the actual position of the control shaft and the detected position thereof is estimated to be large, coordinated control is forbidden and the valve timing change mechanism is operated based on engine load.

Abstract: After power supply from a backup power source to a volatile memory is restored from temporary suspension, a remaining data determining section determines whether data of change history remaining in the volatile memory is data that has been stored immediately before the suspension of the power supply. When it is determined that the data remaining in the volatile memory is not the data that has been stored immediately before suspension of the power supply, a reference value learning section moves an actuator to a limit position, assigns the reference value to an initial value, and clears the change history. When suspension of the power supply from the backup power source reoccurs before completion of the reference value learning by the reference value learning section, a control section invalidates the determination of the remaining data determining section and performs the reference value learning, after the power supply is restored.

Abstract: A variable valve timing and lift mechanism includes an actuator that adjusts the period in which an intake valve is held open by moving a drive element. When a control unit switches the duration, the control unit controls the actuator so that the duration is changed at a first speed when the duration is equal to a first value, and at a second speed when the duration is equal to a second value that is smaller than the first value. The absolute value of the second speed is smaller than the absolute value of the first speed. In effect, the actuator is controlled so that when the duration is in a short-duration range, the duration changes more slowly than when the duration is in a long-duration range.

Abstract: A control device for a variable valve mechanism that avoids the overheating an actuator while reducing adverse effects on the driveability of a vehicle. The actuator adjusts the lift of an intake valve by moving a drive element, and a sensor is used to determine whether the actuator will overheat. A control unit stops the drive element if the lift adjusted by the actuator is equal to or larger than a first predetermined value, when the control unit determines that the actuator will overheat. The actuator may be an electric actuator. In this case, the actuator maintains the drive element in a fixed position when supply of electric power to the actuator is interrupted. The control unit stops the drive element, and interrupts the supply of electric power to the actuator.

Abstract: A brushless motor of a variable valve mechanism varies a actuation parameter of an intake valve of an engine. A position sensor outputs a pulse signal when the brushless motor rotates. A position counter calculates a counter value by counting edges of the pulse signal. A motor control device obtains a detection value of a motor rotational angle based on the counter value when the motor control device is in a powered state. An engine control device determines that the detection value of the motor rotational angle is displaced from the actual value when the engine control device detects that the engine is operating and the motor control device portion is in a non-powered state.

Abstract: An electronic control unit executes a delay control and a load compensation control. In the delay control, the period from when an engine stop request for an engine is made to when the engine is actually stopped is extended. In the load compensation control, the engine power is adjusted according to the driving load of auxiliary devices. Further, if the engine stop request is made during operation of a compressor, which is one of the auxiliary devices, the electronic control unit executes a power reduction control, in which ignition timing is retarded to temporarily reduce the engine power. As a result, in an internal combustion engine that executes the delay control, sudden increases in the engine speed that are likely to occur when an engine stop request is made during operation of auxiliary devices are reliably suppressed.

Abstract: When the engine load is in a high-load zone, an absolute value control is executed, wherein the actual values of valve timings of an intake valve and an exhaust valve and a valve duration of the intake valve are controlled to coincide with respective target values set based on the operating state of an internal combustion engine. When the engine load is in a low-load zone, a relative value control is executed, wherein an actual value of a valve overlap amount of the intake valve and the exhaust valve is controlled to coincide with a target valve overlap amount obtained based on the target values. Therefore, a control method for the internal combustion engine that is appropriate for the operating state of the engine when the operating state of the engine is in transition is obtained.

Abstract: When the engine load is in a high-load zone, an absolute value control is executed, wherein the actual values of valve timings of an intake valve and an exhaust valve and a valve duration of the intake valve are controlled to coincide with respective target values set based on the operating state of an internal combustion engine. When the engine load is in a low-load zone, a relative value control is executed, wherein an actual value of a valve overlap amount of the intake valve and the exhaust valve is controlled to coincide with a target valve overlap amount obtained based on the target values. Therefore, a control method for the internal combustion engine that is appropriate for the operating state of the engine when the operating state of the engine is in transition is obtained.

Abstract: An engine includes two or more banks, VVTL mechanisms provided for the respective banks for changing the operating characteristics of intake valves, and a control device that controls the VVTL mechanisms. The control device controls the VVTL mechanisms by integrating a plurality of pieces of control information corresponding to the respective VVTL mechanisms. When one of the pieces of control information becomes unknown, the control device performs a process of learning the control information with respect to the VVTL mechanism for the bank involving the unknown control information, and continues to control the VVTL mechanism for the other bank or banks, using the corresponding control information.

Abstract: An abnormality determination apparatus for an intake amount control mechanism according to the invention includes a control portion which sets an allowable range of an opening amount of a throttle valve which provided in an intake passageway of an internal combustion engine based at least on an index value of an engine operation state, including an operation amount of accelerator, and on a lift working angle of an intake valve, and which determines that an abnormality is present in a state of driving of the throttle valve if an actual opening amount of the throttle valve is outside the allowable range set.

Abstract: An electronic control unit executes a delay control and a load compensation control. In the delay control, the period from when an engine stop request for an engine is made to when the engine is actually stopped is extended. In the load compensation control, the engine power is adjusted according to the driving load of auxiliary devices. Further, if the engine stop request is made during operation of a compressor, which is one of the auxiliary devices, the electronic control unit executes a power reduction control, in which ignition timing is retarded to temporarily reduce the engine power. As a result, in an internal combustion engine that executes the delay control, sudden increases in the engine speed that are likely to occur when an engine stop request is made during operation of auxiliary devices are reliably suppressed.

Abstract: An electronic control unit 9 performs a delay control for extending the period from when an engine stop request is made to when the engine is actually stopped. During non-execution of the delay control, the electronic control unit 9 adjusts the opening degree of a throttle valve 38 according to an accelerator pedal depression degree. During the execution of the delay control, the electronic control unit 9 adjusts the opening degree of a throttle valve 38 such that the opening degree becomes less than the opening degree during the non-execution of the delay control.