Method for controlling a valve and method for controlling a pump/nozzle device with a valve

A method for controlling a valve with a valve actuating device, which is provided in the form of a piezo actuator, with a valve element, a valve body and a valve seat, the method comprising the steps of:

• closing the valve by moving the valve element at a predeterminable point in time from a predetermined position away from the valve seat into the valve seat by a charging process of the piezo actuator,
• dividing the charging process into a first charging duration, during which a predetermined first amount of electrical energy is fed to the piezo actuator, a subsequent holding time duration, during which the piezo actuator is not controlled, and a subsequent second charging duration, during which a predetermined second amount of electrical energy is fed to the piezo actuator, and
• dependent on the waveform of a voltage at the piezo actuator or a current through the piezo actuator which is characteristic of the oscillation behavior of the piezo actuator during the holding time duration, adapting the holding time duration and/or the first charging duration in order to ensure precise control of the valve.

An arrangement for controlling a valve with a valve actuating device, which is provided in the form of a piezo actuator, with a valve element, a valve body and a valve seat, comprising:

• means for closing the valve by moving the valve element at a predeterminable point in time from a predetermined position away from the valve seat into the valve seat by a charging process of the piezo actuator,
• means for dividing the charging process into a first charging duration, during which a predetermined first amount of electrical energy is fed to the piezo actuator, a subsequent holding time duration, during which the piezo actuator is not controlled, and a subsequent second charging duration, during which a predetermined second amount of electrical energy is fed to the piezo actuator, and
• dependent on the waveform of a voltage at the piezo actuator or a current through the piezo actuator which is characteristic of the oscillation behavior of the piezo actuator during the holding time duration, means for adapting the holding time duration and/or the first charging duration in order to ensure precise control of the valve.