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 a variable valve unit provided with a variable valve mechanism that varies opening characteristics of an engine valve by rotary motion of a control shaft, an actuator that generates a rotary motion of the control shaft, a stopper restricting the rotary motion of the control shaft, and an angle sensor capable of outputting signals corresponding to angle positions of the control shaft, when the signal of the angle sensor at an angle position where the rotation of the control shaft is restricted by the stopper are learned, the actuator is controlled such that the control shaft is pressed against the stopper, after which drive torque of the actuator is reduced and with the drive torque reduced, signals of the then-angle sensor are stored.

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 intake-air quantity control system of an engine employing a variable valve operating device capable of controlling a cylinder intake-air quantity by variable control of an operating characteristic of an intake valve, in a normal intake-valve operating mode a target operating characteristic of the intake valve is determined based on a target cylinder intake-air quantity calculated based on a target engine torque. In a predetermined high-load range, in particular, at full-load operation, the target operating characteristic is switched to a high-load period valve operating characteristic, preset to be suitable for the predetermined high-load range.

Abstract: This invention aims at providing a control circuit of power supply in which a secondary battery and a device are connected in parallel, to output capable of preventing over-charging of the secondary battery and supplying power from the secondary battery to the device, and a control method of the power supply. A device 5G and a secondary battery 2G are connected to a DC-DC converter 1G in parallel. The device 5G is supplied with both a power from the DC-DC converter 1G and a power from the secondary battery 2G. When the secondary battery 2G is in non-charging state, an offset circuit 15G supplies a positive offset for reducing a difference of voltage between a detection signal Vx1G and reference voltage e1G to a reference voltage e1G corresponding to a charging inhibit signal CAS.

Abstract: A DC-DC converter for generating a stable output voltage and being applicable to a transient load fluctuation. The DC-DC converter detects an input current, and compares the input current with a rated current of an external power supply. The DC-DC converter controls a positive charging current that is supplied to a secondary battery in accordance with a consumption current of a load so that the input current does not exceed the rated current. The DC-DC converter further controls a negative charging current that is supplied from the secondary battery to the load when the load requires an input current exceeding the rated current.

Abstract: In an intake-air quantity control system of an engine employing a variable valve operating device capable of controlling a cylinder intake-air quantity by variable control of an operating characteristic of an intake valve, in a normal intake-valve operating mode a target operating characteristic of the intake valve is determined based on a target cylinder intake-air quantity calculated based on a target engine torque. In a predetermined high-load range, in particular, at full-load operation, the target operating characteristic is switched to a high-load period valve operating characteristic, preset to be suitable for the predetermined high-load range.

Abstract: At the time of obtaining a difference in intake air amount between right and left banks in a V-type engine, a target value of a lift-amount/operation-angle-varying mechanism provided for each of the banks is set to a target value at which flow velocity of intake air passing through an intake valve becomes almost sound velocity. In a state in which the flow velocity of intake air passing through the intake valve becomes almost sound velocity, a difference in the intake air amount in the right and left banks is detected and, to reduce the difference, a correction value for a target value of a valve lift is set for each of the banks.

Abstract: A step-up/step-down DC-DC converter for reducing loss caused by activation and inactivation of transistors. An error amplifier included in a control circuit generates an error signal in accordance with voltage difference between an output voltage and a reference voltage. A PWM comparator compares a triangular wave signal and the error signal to generate a control pulse signal having a pulse width that is in accordance with the voltage difference between the output voltage and the reference voltage. A pulse detector monitors the control pulse signal and generates a mode switch signal for switching the operation mode of the DC-DC converter in accordance with a monitoring state of the control pulse signal. A switch provides the PWM comparator with the triangular wave signal or an offset signal, which is generated by adding an offset voltage to the triangular wave signal, in response to the mode switch signal.

Abstract: An internal combustion engine (1) causes an air/fuel mixture in a cylinder to combust due to ignition by a spark plug (14). The engine controller (50) calculates a crank angle at knock on the basis of an operating state of the engine (1) (53–54), calculates a knock intensity on the basis of this crank angle at knock (54), calculates a limit ignition timing at which knock is not generated, on the basis of the knock intensity (54), and controls the ignition timing of the spark plug (14) to the limit ignition timing at which knock is not generated (55). Therefore, suitable control of the ignition timing is achieved, by means of a small number of adaptation steps.

Abstract: An internal combustion engine (1) causes an air/fuel mixture in a cylinder to combust due to ignition by a spark plug (14). The engine controller (50) calculates a temperature and pressure in the cylinder on the basis of the operating state of the engine (1) (531), calculates a limit ignition timing at which knock is not generated, on the basis of the temperature and pressure in the cylinder (54), and controls an ignition timing of the spark plug (14) to the limit ignition timing at which knock is not generated (55). Therefore, suitable control of the ignition timing is achieved, by means of a small number of adaptation steps.

Abstract: A step-up/step-down DC-DC converter for reducing loss caused by activation and inactivation of transistors. An error amplifier included in a control circuit generates an error signal in accordance with voltage difference between an output voltage and a reference voltage. A PWM comparator compares a triangular wave signal and the error signal to generate a control pulse signal having a pulse width that is in accordance with the voltage difference between the output voltage and the reference voltage. A pulse detector monitors the control pulse signal and generates a mode switch signal for switching the operation mode of the DC-DC converter in accordance with a monitoring state of the control pulse signal. A switch provides the PWM comparator with the triangular wave signal or an offset signal, which is generated by adding an offset voltage to the triangular wave signal, in response to the mode switch signal.

Abstract: To present a control circuit of a DC—DC converter to be incorporated in a logic circuit, having a digital error amplifier capable of controlling the gain depending on an input voltage and an output voltage, without requiring a resistance or a capacitor of high precision used in a feedback circuit or the like. A ?? AD converter type error amplifier 10 includes an arithmetic unit 20, an integrating unit 21, a 1-bit quantizing unit 22, a D/A converter 23, and a first counter 24. The arithmetic unit 20 outputs a differential signal of an output voltage Vout and an average output voltage AV. The integrating unit 21 outputs an integral signal by integrating the differential signal. The 1-bit quantizing unit 22 outputs a 1-bit digital signal by quantizing the integral signal. The D/A converter 23 converts from digital to analog depending on a 1-bit digital signal.

Abstract: An internal combustion engine control apparatus basically comprises a reference intake air quantity calculating section, a maximum intake air quantity calculating section and an engine control section. The reference intake air quantity calculating section is configured to calculate a reference intake air quantity corresponding to when an intake air is taken in as a sonic flow. The maximum intake air quantity calculating section is configured to calculate a theoretical maximum intake air quantity. The engine control section is configured to control the engine by using an intake air quantity function between a first value obtained by dividing the reference intake air quantity by the maximum intake air quantity and a second value obtained by dividing an actual intake air quantity corresponding to the valve characteristics of the intake valve by the maximum intake air quantity.

Abstract: An internal combustion engine control apparatus basically comprises a reference intake air quantity calculating section, a maximum intake air quantity calculating section and an engine control section. The reference intake air quantity calculating section is configured to calculate a reference intake air quantity corresponding to when an intake air is taken in as a sonic flow. The maximum intake air quantity calculating section is configured to calculate a theoretical maximum intake air quantity. The engine control section is configured to control the engine by using an intake air quantity function between a first value obtained by dividing the reference intake air quantity by the maximum intake air quantity and a second value obtained by dividing an actual intake air quantity corresponding to the valve characteristics of the intake valve by the maximum intake air quantity.

Abstract: An internal combustion engine (1) causes an air/fuel mixture in a cylinder to combust due to ignition by a spark plug (14). An engine controller (50) calculates an ignition delay of the gas in the cylinder on the basis of an operational state of the engine (1)(53), and it calculates a knock generation index which is an indicator of the occurrence of knock on the basis of the ignition delay (53). The controller (50) calculates a limit ignition timing at which knock is not generated, on the basis of the knock generation index (54), and by controlling the ignition timing of the spark plug (14) to the limit ignition timing (55), appropriate control of the ignition timing is achieved by means of a small number of adaptation steps.

Abstract: An internal combustion engine (1) causes an air/fuel mixture in a cylinder to combust due to ignition by a spark plug (14). The engine controller (50) calculates a temperature and pressure in the cylinder on the basis of the operating state of the engine (1) (531), calculates a limit ignition timing at which knock is not generated, on the basis of the temperature and pressure in the cylinder (54), and controls an ignition timing of the spark plug (14) to the limit ignition timing at which knock is not generated (55). Therefore, suitable control of the ignition timing is achieved, by means of a small number of adaptation steps.

Abstract: An internal combustion engine (1) causes an air/fuel mixture in a cylinder to combust due to ignition by a spark plug (14). An engine controller (50) calculates an ignition delay of the gas in the cylinder on the basis of an operational state of the engine (1)(53), and it calculates a knock generation index which is an indicator of the occurrence of knock on the basis of the ignition delay (53). The controller (50) calculates a limit ignition timing at which knock is not generated, on the basis of the knock generation index (54), and by controlling the ignition timing of the spark plug (14) to the limit ignition timing (55), appropriate control of the ignition timing is achieved by means of a small number of adaptation steps.

Abstract: An internal combustion engine (1) causes an air/fuel mixture in a cylinder to combust due to ignition by a spark plug (14). The engine controller (50) calculates a crank angle at knock on the basis of an operating state of the engine (1) (53-54), calculates a knock intensity on the basis of this crank angle at knock (54), calculates a limit ignition timing at which knock is not generated, on the basis of the knock intensity (54), and controls the ignition timing of the spark plug (14) to the limit ignition timing at which knock is not generated (55). Therefore, suitable control of the ignition timing is achieved, by means of a small number of adaptation steps.

Abstract: A wall surface of a combustion chamber (5) of an internal combustion engine (1) is divided into a low temperature wall surface (5b) and a high temperature wall surface (5a, 6a, 15a) comprising other components, and behavior models of the fuel adhering to these wall surfaces are created. By determining the fuel ratio which vaporizes from the wall surfaces and burns, and the fuel ratio which is discharged without being burnt, in respective models according to the wall surface temperatures, particularly under transient conditions, these behavior models allow the fuel amount burnt in the combustion chamber (5) and the fuel amount discharged in the exhaust gas to be precisely known.