Patent attributes
A fuel injection system comprising an accumulator volume (10) arranged to be charged with fuel by means of a high pressure fuel pump (12) and for supplying fuel at a first injectable pressure level to a plurality of fuel injectors (22), wherein each injector (22) includes a delivery passage (16, 20), a valve needle (30), which is engageable with a seating to control fuel injection, and a control valve (26) for controlling fuel pressure within a control chamber (28) so as to control movement of the valve needle (30). The control valve (26) has a first operating position in which the control chamber (28) communicates with a low pressure drain and communication between the control chamber (28) and the delivery passage (16, 20) is prevented and a second operating position in which the control chamber (28) communicates with the delivery passage (16, 20) and communication between the control.
