Silenced fuel pump for a direct injection system

摘要

A fuel pump for a direct-injection system provided with a common rail comprises a pumping chamber defined in a main body. A piston is mounted in a sliding manner inside the pumping chamber to cyclically vary volume of the pumping chamber. A suction channel is connected to the pumping chamber and regulated by a suction valve. A delivery channel is connected to the pumping chamber and regulated by a delivery valve. A flow-rate-adjustment device is mechanically coupled to the suction valve to keep, when necessary, the suction valve substantially open during pumping of the piston and includes a control rod that is coupled to the suction valve and an electromagnetic actuator that acts on the control rod and has a one-way hydraulic brake that is integral to and substantially slows movement of the control rod.