Method for bounce suppression of a valve switched by a piezo actuator

Abstract

A method for bounce suppression of a valve member operated by a piezo actuator during the closing phase of a valve in an internal combustion engine, having the following steps: partial discharging of the piezo actuator, whereby the valve member is braked even before reaching the valve seat, interruption of the discharge of the piezo actuator, whereby the piezo actuator is upset by the valve member and builds up an electric charge, renewed discharging of the piezo actuator, the residual charge after partial discharge and the charge built up during the charge interruption being at least partially dissipated. It is provided, according to the present invention, briefly to interrupt the discharge process, whereby the piezo actuator absorbs the energy of the valve member and, even before an elastic rebound takes place, the piezo actuator is discharged again, in order to dissipate the energy absorbed by the piezo actuator.

Dependencies are inferred from the claim text.