High-pressure pump with a device for regulating the flow rate for a fuel-injection system

摘要

The high-pressure pump ( 7 ) comprises a number of pumping elements ( 18 ) actuated in reciprocating motion through corresponding suction and delivery strokes. Each pumping element ( 18 ) is provided with a corresponding intake valve ( 25 ) in communication with an intake pipe ( 10 ) supplied by a low-pressure pump ( 9 ). Set on the intake pipe ( 10 ) is an on-off solenoid valve ( 27 ) having a reduced flow rate substantially of the same order of magnitude as the maximum amount of fuel that can be injected by an injector ( 5 ). The solenoid valve ( 27 ) is controlled in a chopped way in synchronism with an intermediate part ( 32 ) of the suction stroke of each pumping element ( 18 ).