Patent ID: 7444988

Claim:
An accumulation volume fuel-injection system for an internal-combustion engine having at least one cylinder, the system comprising: a pump designed to send fuel at high pressure to an accumulation volume; at least one injector supplied by said accumulation volume and actuatable for injecting pressurized fuel into said cylinder during an injection phase, said injection phase having a variable duration, a starting point, an end point, and a midpoint between the starting point and the end point, wherein said pump includes at least one reciprocating-motion pumping element with a compression stroke in synchronism with said injection phase; an electrical control unit including a chopper control unit; and a by-pass solenoid valve for the fuel sent by said pump into the accumulation volume; wherein said pumping element has an instantaneous maximum flow rate of the same order of magnitude as the maximum flow rate of said injector, said by-pass solenoid valve being controlled by the chopper control unit barycentrically with both said compression stroke and said midpoint of said injection phase.