Patent ID: 6889658

Claim:
In a fuel injection system for an internal combustion engine, having one high-pressure fuel pump ( 10 ) and one fuel injection valve ( 12 ), communicating with it, for each cylinder of the engine, in which the high-pressure fuel pump ( 10 ) has a pump piston ( 18 ), driven in a reciprocating motion by the engine, which piston defines a pump work chamber ( 22 ) that communicates with a pressure chamber ( 40 ) of the fuel injection valve ( 12 ), and the fuel injection valve ( 12 ) has at least one first injection valve member ( 28 ), by which at least one first injection opening ( 32 ) is controlled and which is movable in an opening direction ( 29 ), counter to a closing force, by the pressure prevailing in the pressure chamber ( 40 ), and having a first electrically controlled control valve ( 23 ), by which a communication of the pump work chamber ( 22 ) with a relief chamber is controlled, the fuel injection valve ( 12 ) has a second injection valve member ( 128 ), guided displaceably inside the hollow first injection valve member ( 28 ), by means of which second injection valve member at least one second injection opening ( 132 ) is controlled, and which second injection valve member is movable in an opening direction ( 29 ) counter to a closing force by the pressure prevailing in the pressure chamber; and wherein the second injection valve member ( 128 ) is acted upon at least indirectly by the pressure prevailing in a fuel-filled control chamber ( 50 ; 246 ), which pressure is generated by a pressure source ( 52 ) as a function of operating parameters of the engine, as a result of which the opening pressure of at least the second injection valve member ( 128 ) is variable.