F02D2041/2079

Fluid injector and method and apparatus for operating the fluid injector
09593652 · 2017-03-14 · ·

A fluid injector has a longitudinal axis (L) and a valve needle (12), which is axially moveable and operable to prevent a fluid injection in a closing position and to permit the fluid injection in further positions. The fluid injector also has an armature (14) which is mechanically coupled to the valve needle (12). Furthermore, the fluid injector has a solenoid assembly (30) which has at least a first and second coil (34, 36) and which is operable to magnetically actuate the armature (14) via an electrical signal (V) applied to at least one predetermined assortment of the at least two coils (34, 36).

Fluid injector and method for operating a fluid injector

A fluid injector includes a valve body, a valve needle and axially moveable in the valve body between a closing position that prevents a fluid injection and further positions that permit the fluid injection, an armature coupled to the valve needle for displacing the valve needle away from the closing position, and a solenoid assembly including at least a first and second coil and operable to magnetically actuate the armature via an electrical signal. A method for operating the fluid injector includes applying the electrical signal to the first coil to generate a magnetic field to move the armature for displacing the valve needle away from the closing position, evaluating a voltage across terminals of the first coil, and controlling the second coil with a further electrical signal to saturate a magnetic field in a portion of the valve body between the armature and solenoid assembly during evaluating the voltage.