Abstract: A fuel injector for use in an internal combustion engine includes a valve member that is moveable within a bore of an injection nozzle so as to be engageable with a valve seat region to control fuel delivery through one or more nozzle outlets, an injector body housing an actuator that is operable to move the valve member within the bore, and defining an accumulator volume for storing high pressure fuel. The fuel injector includes a damping chamber in fluid communication with the accumulator volume through a fluid passage, the damping chamber serving to reduce pressure wave activity within the accumulator volume.

Abstract: A fuel injector for use in an internal combustion engine includes a valve member that is moveable within a bore of an injection nozzle so as to be engageable with a valve seat region to control fuel delivery through one or more nozzle outlets, an injector body housing an actuator that is operable to move the valve member within the bore, and defining an accumulator volume for storing high pressure fuel. The fuel injector includes a damping chamber in fluid communication with the accumulator volume through a fluid passage, the damping chamber serving to reduce pressure wave activity within the accumulator volume.

Abstract: A fuel injector for use in an internal combustion engine includes a valve member that is moveable within a bore of an injection nozzle so as to be engageable with a valve seat region to control fuel delivery through one or more nozzle outlets, an injector body housing an actuator that is operable to move the valve member within the bore, and defining an accumulator volume for storing high pressure fuel. The fuel injector includes a damping chamber in fluid communication with the accumulator volume through a fluid passage, the damping chamber serving to reduce pressure wave activity within the accumulator volume.

Abstract: A fuel injector for use in an internal combustion engine includes a valve member that is moveable within a bore of an injection nozzle so as to be engageable with a valve seat region to control fuel delivery through one or more nozzle outlets, an injector body housing an actuator that is operable to move the valve member within the bore, and defining an accumulator volume for storing high pressure fuel. The fuel injector includes a damping chamber in fluid communication with the accumulator volume through a fluid passage, the damping chamber serving to reduce pressure wave activity within the accumulator volume.

Abstract: A piezoelectric actuator comprises a stack of piezoelectric elements formed from piezoelectric material, a plurality of positive internal electrodes interdigitated with a plurality of negative internal electrodes to define active regions of the piezoelectric material which are responsive to a voltage being applied across the internal electrodes, in use. The active regions are responsive to voltage applied across the internal electrodes, in use. The piezoelectric actuator also comprises an external positive electrode for connection to the positive internal electrodes and an external negative electrode for connection to the negative internal electrodes.

Abstract: A fuel injector comprising a valve needle, engagable with the seating to control fuel flow through a fuel outlet, the valve needle having a thrust surface oriented such that the application of fuel under pressure thereto applies a force to the valve needle urging the valve needle away from the seating. The fuel injector also comprises a valve member for controlling fuel pressure within a control chamber and a piston member slidable within a bore and defining, with the bore, the control chamber. The piston member is exposed to fuel pressure within the control chamber and is arranged to transmit a force applied by the fuel pressure to the valve needle. The piston member has an effective surface area exposed to the fuel pressure which is greater than that of the thrust surface so as to urge the valve needle towards the seating.

Abstract: A fuel injector comprising a valve needle, engagable with the seating to control fuel flow through a fuel outlet, the valve needle having a thrust surface oriented such that the application of fuel under pressure thereto applies a force to the valve needle urging the valve needle away from the seating. The fuel injector also comprises a valve member for controlling fuel pressure within a control chamber and a piston member slidable within a bore and defining, with the bore, the control chamber. The piston member is exposed to fuel pressure within the control chamber and is arranged to transmit a force applied by the fuel pressure to the valve needle. The piston member has an effective surface area exposed to the fuel pressure which is greater than that of the thrust surface so as to urge the valve needle towards the seating.