Patent ID: 9328707
Filing Date: 2016-05-03
CPC Classification: F02M

Claim Text:
1. A fuel injector having injection nozzles controlled by a nozzle needle and having a control chamber ( 7 ), which communicates with a high- and a low-pressure side of the injector, which is designed as a working chamber of a displacer ( 6 ) coupled to the nozzle needle for driving, and which is switched by means of a control valve arrangement ( 10 ) between a closing pressure, at which the nozzle needle is set to a closed position thereof by the displacer ( 6 ), and an opening pressure, at which the nozzle needle, together with the displacer ( 6 ), moves into an open position, characterized in that the control chamber ( 7 ) includes a force or pressure sensor ( 20 ) for detecting characteristic pressure changes during the closing and opening of the nozzle needle, in that an outlet aperture ( 9 ) of the control chamber ( 7 ) on the low-pressure side can be controlled by means of a sleeve-shaped closing body ( 11 ), which is arranged movably on a guide rod ( 13 ) coaxial with the outlet aperture ( 9 ), in that the guide rod ( 13 ) is coupled at an end remote from the aperture to the force or pressure sensor ( 20 ), and in that the force or pressure sensor ( 20 ) communicates on an output side with a signal evaluator or engine controller, which evaluates the sensor signals in order to determine closing times of the nozzle needle and the pressure of a high-pressure fuel source communicating with the fuel injector.