摘要:
A valve has a piezo actuator, a valve element, a valve body and a valve seat. At a predeterminable point in time, the valve element is controlled by a discharging process of the piezo actuator from a position in which it rests against the valve seat to a predetermined position located at a distance from the valve seat. The discharging process is divided into a first discharging period during which a predetermined first amount of electrical energy is discharged from the piezo actuator, a subsequent holding time period during which the piezo actuator is not controlled, and a subsequent second discharging period during which a predetermined second amount of electrical energy is discharged. The holding time duration and/or the first discharging period are/is adapted according to the course of a value that is not characteristic of the oscillation behavior of the piezo actuator during the holding time period.
摘要:
A method for injecting a fluid, in particular a fuel, performs the following steps: A nozzle (1) which can be actuated by a piezo element (5) is provided. A current pulse (12a) is supplied to the piezo element (5). The capacity (16) of the piezo element (5) is recorded at the time when the current pulse (12a) is supplied. An actual characteristic curve of the injection is recorded based on the capacity (16). The current pulse (12a) is regulated in order to optimize the injection based on the actual characteristic curve of the injection.
摘要:
In a method or a device for forming an electric control signal for an injection impulse of a position-controlled fuel injector, particularly of a common-rail or pump-nozzle injection system, he course of the electric control signal can be selected freely in regard to the pulse edges (injection rate changes Q), the holding period (Δt) and the injection rate (Q). This offers the advantage that the combustion process can be better optimized with respect to low emissions, low consumption and for meeting tightened legal regulations.
摘要:
In a method or a device for forming an electric control signal for an injection impulse of a position-controlled fuel injector, particularly of a common-rail or pump-nozzle injection system, the course of the electric control signal can be selected freely in regard to the pulse edges (injection rate changes Q), the holding period (Δt) and the injection rate (Q). This offers the advantage that the combustion process can be better optimized with respect to low emissions, low consumption and for meeting tightened legal regulations.
摘要:
A valve has a piezoelectric actuator with a valve element, a valve body and a valve seat. In order to control the valve, the valve element is moved into the valve seat from a position remote from the valve seat by means of a charging process at a prescribable first time. A first value is determined being characteristic of the electrical power supplied to the piezoelectric actuator when the valve element meets the valve seat. A second value is determined being characteristic of the electrical power supplied to the piezoelectric actuator when the charging process of the piezoelectric actuator is concluded. An actual difference value between the second value and the first value is determined. A difference between a setpoint difference value and the actual difference value is supplied to a controller. An actuating signal for charging the piezoelectric actuator is determined as a function of the actuating variable.
摘要:
In a method for determining the closure time for a valve, operated by a piezoelectric actuator, in order to record the closing time, the voltage at the piezoelectric actuator is recorded and the time is recorded at which the voltage has a maximum difference value from a comparison curve. The difference curve is generated between a start and an end point for a measured curve, having the voltage values applied to the piezoelectric actuator. A precise determination of the closing time can thus be carried out.