Patent ID: 7228844

Claim:
A storage-volume fuel injection system for an internal combustion engine having a plurality of cylinders, the injection system comprising: a pump for supplying high-pressure fuel to a storage volume, and a plurality of injectors supplied by said storage volume and each activated to perform an injection of pressurized fuel into a corresponding cylinder of the engine, said injection having a maximum pressurized fuel flow depending on the operating conditions of the engine; said pump having at least one reciprocating pumping element performing an intake stroke and a compression stroke for each of said injections, said pumping element having a maximum instantaneous flow greater than the maximum flow of each of said injectors; and a control device being provided to vary the quantity of fuel supplied by said pump to the storage volume, said control device including an on-off solenoid valve located along the intake conduit of said pumping element, said on-off solenoid valve being pulse width modulation controlled by a chopper control unit synchronously with said intake stroke to introduce into the compression chamber of said pumping element a fuel volume unequivocally defined, for a predetermined rotation speed of said pump, by an opening instant and a closing instant of said on-off solenoid valve during said intake stroke.