Method for determining closing of needle of fuel injector in self-ignition internal combustion engine, involves determining voltage signal of piezo-elements, and determining time point for entering closing position of needle based on signal

摘要

The method involves determining a voltage signal of piezo-elements that are installed into a recess of a valve. A time point for entering a closing position of a needle (5) of the valve is determined based on the determined signal, where the needle is axial movably arranged in a valve needle body (2) and controls a valve needle point (6) in an injection aperture of the valve according to an open position and the closing position of the needle. The signal is utilized as an input to a quantity correction function for controlling the valve or an input to an on-board diagnosis (OBD) process. An independent claim is also included for an arrangement for determining closing of a needle of a valve.