摘要:
A method and a device for operating an internal combustion engine having multiple cylinders allows for an operating state of the internal combustion engine to be switched over as quickly as possible following the receipt of a switchover request. For this purpose, at least one intake or exhaust valve of a cylinder is switched off or at least one switched-off intake or exhaust valve of the cylinder is switched on again in at least one operating state of the internal combustion engine in response to the switchover request. With the receipt of a switchover request, a delay time or a delay crank angle is ascertained which is required for switching off or switching on again the intake or exhaust valve of one of the cylinders. Starting from the time or crank angle of the receipt of the switchover request and taking into account the ascertained delay time or the ascertained delay crank angle, the cylinder is selected whose at least one exhaust valve following the expiration of the delay time or of the delay crank angle starting from the time or crank angle of the receipt of the switchover request is the next to open in the switched-on state or would be the next to open, though it is switched off. This cylinder is ascertained as the one whose at least one intake or exhaust valve is designated to be the first to be switched off or switched on again following the receipt of the switchover request.
摘要:
In a method for operating a camshaft adjusting device, using an actuating drive, the actual setting of a camshaft with respect to the rotation of the crankshaft is followed corresponding to a setpoint setting ascertained in a control unit. In response to the occurrence of a lasting system deviation between the actual setting and the setpoint setting, an error signal is generated. The error signal is designed in multiple stages as a function of the system deviation, different weightings being imputed to the individual stages of the fault indication. By this measure, the fault indications of different weightings may be processed. Faults that are not serious, but nevertheless require attention, may be treated separately from serious faults.
摘要:
A precontrol is carried out for the control of the position of the camshaft via a camshaft actuator especially in internal combustion engines and preferably in such engines of motor vehicles. For this purpose, a control for the position of a camshaft is carried out by a camshaft actuator with reference to a reference position in dependence upon the actual position of the camshaft and in dependence upon a determined desired position for the camshaft. An actuating signal for driving the actuator for the camshaft is determined from the desired position and the actual position of the camshaft actuator. In the determination of the actuating signal, a precontrol component is considered which is determined based on state quantities characterizing the operation of the camshaft actuator.
摘要:
A method and a device are provided for operating a drive unit of a vehicle having an engine which in a first operating state is operated with a first number of cylinders and in a second operating state is operated with a second number of cylinders. The first number of cylinders and the second number of cylinders are different from one another. The switchover of the engine between the first operating state and the second operating state is adapted to the driver type or the driving situation. Switchover between the first operating state and the second operating state is delayed as a function of the driver type or the driving situation.
摘要:
The invention is directed to a method of avoiding an erroneous fault announcement when diagnosing a tank-venting system for a motor vehicle having an internal combustion engine. In the method a change in elevation is determined at which the motor vehicle is operated during the diagnosis and this change in elevation is considered in the determination of the diagnostic result.
摘要:
The invention is directed to a method of checking a tank-venting apparatus for a motor vehicle equipped with a fuel tank and an internal combustion engine having an intake pipe. The apparatus includes an adsorption filter having a venting end and an intake end, a supply line connecting the intake end to the tank and a connecting line interconnecting the intake pipe of the engine and the intake end of the adsorption filter. A tank-venting valve is mounted in the connecting line between the intake pipe and the intake end of the adsorption filter and a drive unit for actuating the tank-venting valve. The method includes the steps of: changing the open state of the tank-venting valve when a pregiven operating state range of the engine is present; detecting the difference pressure between the pressure at the intake end of the adsorption filter and the ambient pressure; checking if the difference pressure or the end value of the difference pressure change lies in a predetermined range after the open state of the tank-venting valve is changed; and, issuing a fault announcement if neither the difference pressure, the time constant of the difference pressure change nor the end value of the difference pressure change lies in said predetermined range. The invention utilizes the realization that the difference pressure is based on the gas flow into and out of the adsorption filter. The difference pressure drops when the outflow is clogged or when there is a leak. On the other hand, the difference pressure increases when the inflow is clogged. In this way, the operability of the tank-venting apparatus can be checked in a simple manner.
摘要:
A method and a device for operating an internal combustion engine are provided which make it possible to implement different deceleration requests to the internal combustion engine by switching over between half engine operation and full engine operation. A deceleration request is received particularly in a nonoperating state. A switchover is made between a first operating state and a second operating state of the internal combustion engine as a function of the magnitude of the deceleration request. The first operating state and the second operating state differ, in this instance, in the number of cylinders whose charge changing process is interrupted.
摘要:
A method and a device for operating an internal combustion engine make it possible to shift the combustion limit. In this context, a predefined output variable of the internal combustion engine such as the torque, for example, is realized in at least one operating state of the internal combustion engine by at least a retardation of an ignition angle. It is checked whether, due to the retardation of the ignition angle, a variable like, for example, a misfiring, characteristic for the combustibility of the air/fuel mixture in a combustion chamber of the internal combustion engine, exceeds a predefined limiting value in terms of a deterioration of the combustibility, and in this case, at least one actuator of the internal combustion engine, different from an actuator for setting the ignition angle, such as the exhaust-gas recirculation valve or EGR valve, for instance, is controlled along the lines of improving the combustibility of the air/fuel mixture.
摘要:
A method and a device for operating internal combustion engine, in particular in an unfired state, are described, which make possible a largely jerk-free switchover between two operating states of internal combustion engine, having different numbers of cylinders that are activated regarding the charge cycle. Air is supplied to the internal combustion engine via an actuator in an air supply, and the quantity of air supplied to the internal combustion engine is influenced by the position of the actuator. A charge cycle state of at least one cylinder of the internal combustion engine is changed. The position of the actuator in the air supply is changed with the change of the charge cycle state of the at least one cylinder.
摘要:
A method and a device for operating an internal combustion engine are provided which make it possible to implement different deceleration requests to the internal combustion engine by switching over between half engine operation and full engine operation. A deceleration request is received particularly in a nonoperating state. A switchover is made between a first operating state and a second operating state of the internal combustion engine as a function of the magnitude of the deceleration request. The first operating state and the second operating state differ, in this instance, in the number of cylinders whose charge changing process is interrupted.