Patent ID: 7219659

Claim:
In a fuel injection system for an internal combustion engine, the system including a high-pressure fuel source ( 1 , 4 ), a fuel injector ( 10 ) which can be supplied with fuel from a high-pressure fuel source ( 1 , 4 ) including a high-pressure pumping unit ( 1 ) and which includes an injection valve member ( 37 ) for opening or closing injection openings ( 43 ), and a low-pressure circuit ( 64 ) including a prefeed pump ( 55 ) which pumps fuel from a fuel tank ( 14 ), the improvement comprising return conduits ( 50 , 52 ; 13 , 53 ) for delivering partial return fuel quantities, depressurized to the prefeed pressure of the prefeed pump ( 55 ), to the low-pressure circuit ( 64 ) from pressure boosters ( 7 , 52 ) or from fuel injectors ( 10 ), the partial return fuel quantities being delivered inside an infeed portion ( 60 ) wherein the low-pressure circuit ( 64 ) comprises a compensation container ( 51 ) acted upon by the returns ( 50 , 52 ) from the pressure booster ( 7 ).