Patent ID: 7261087

Claim:
A high pressure variable flow-rate pump for a fuel injection system of an internal-combustion engine, comprising at least one pumping element ( 18 ), which is actuated in reciprocating motion through suction and delivery strokes, said pumping element ( 18 ) being provided with an intake valve ( 25 ) in communication with an intake pipe ( 10 ), and with a delivery valve ( 30 ) in communication with a delivery pipe ( 8 ), said variable flow rate of said pump being regulated by a switched on/off solenoid valve ( 27 ), arranged on said intake pipe ( 10 ) and controlled by a control unit ( 16 ) in synchronism with said suction stroke; characterized in that said solenoid valve ( 27 ) is provided with a relatively wide cross section to enable it to supply the pumping element ( 18 ) during a variable part ( 32 , 32 ′) of said suction stroke, said control unit ( 16 ) controlling said solenoid valve ( 27 ) as to be open at the beginning of said suction stroke and modulating with continuity its closing during said suction stroke.