Abstract: A fuel injector includes a housing extending along an injector axis. A pintle has an axially extending pintle shaft and a radially projecting annular collar with a collar surface, the pintle being axially moveable between an open position and a closed position. An armature is axially guided in the housing between a proximal position and a distal position, the armature having an axial through-hole in which the pintle shaft is guided and an armature surface which engages the collar surface, thereby moving the pintle into the open position when the armature moves to the proximal position. A first resilient member biases the pintle in the distal direction and a second resilient member biases the armature in the distal direction. The armature surface and the collar surface are slanted with respect to the injector axis and one of the armature surface and the collar surface is convex curved.

Abstract: A fuel injector includes a housing extending along an injector axis. A pintle has an axially extending pintle shaft and a radially projecting annular collar with a collar surface, the pintle being axially moveable between an open position and a closed position. An armature is axially guided in the housing between a proximal position and a distal position, the armature having an axial through-hole in which the pintle shaft is guided and an armature surface which engages the collar surface, thereby moving the pintle into the open position when the armature moves to the proximal position. A first resilient member biases the pintle in the distal direction and a second resilient member biases the armature in the distal direction. The armature surface and the collar surface are slanted with respect to the injector axis and one of the armature surface and the collar surface is convex curved.

Abstract: A fuel pump includes a mechanical regulating valve arranged in a pump body which modulates the pressure in a high pressure space so that the pressure matches the engine demand. Modulation by the regulating valve requires adjustment of the inlet fuel quantity, adjustment of the volume of the high pressure space, and control of a return fluid communication enabling fuel to exit the high pressure reservoir.

Abstract: A fuel pump includes a mechanical regulating valve arranged in a pump body which modulates the pressure in a high pressure space so that the pressure matches the engine demand. Modulation by the regulating valve requires adjustment of the inlet fuel quantity, adjustment of the volume of the high pressure space, and control of a return fluid communication enabling fuel to exit the high pressure reservoir.

Abstract: A fuel injector comprising an injector body having a spray aperture; a pintle extending within the injector body for axial movement between a closed position and an open position; said pintle head comprising a tapered portion engageable against the valve seat of the spray aperture and a cylindrical portion upstream of said tapered portion, an annular channel being provided defining a first part of a flow passage upstream of the spray aperture, wherein a discontinuity is provided downstream of the annular channel and upstream of the spray aperture to generate cavitation when the pintle stroke exceeds a predetermined limit to thereby generate a virtual channel of constant cross section downstream of the annular channel whereby the flow rate of the fuel flowing through said spray aperture is substantially independent of the stroke of the pintle when the pintle is in its open position.

Abstract: A fuel injector comprises an injector body having a tip portion defining a spray aperture; a pintle extending within the tip portion for axial movement between an extended position and a retracted position, the pintle having a head portion engageable with the spray aperture to close the spray aperture when the pintle is in its retracted position; biasing means being provided for biasing the pintle towards its retracted position; and solenoid means for selectively moving the pintle into said extended position; said solenoid means comprising an electromagnetic coil and a moveable armature capable of being acted upon by the coil to urge the pintle towards its extended position; wherein the pintle and armature are separable from one another whereby the armature can decouple from the pintle when the pintle moves from its extended position to its retracted position.

Abstract: A fuel injector for an internal combustion engine, the injector comprising an injector body having a tip portion defining at least one spray aperture; a pintle extending within the tip portion, the pintle having a head portion engageable with a valve seat to close the spray aperture, the pintle being axially moveable between a closed position wherein the head portion abuts the valve seat and an open position wherein the head portion is spaced from the valve seat; actuating means for selectively urging the pintle towards its open position; guide means being provided within the injector body guiding the pintle for axial movement between its closed and open positions; a fuel supply chamber being defined within the injector body between the spray aperture and the guide means, characterized in that the diameters of the guide means and valve seat are selected such that the pintle is substantially pressure balanced.

Abstract: A fuel injector comprises an injector body having a tip portion defining a spray aperture; a pintle extending within the tip portion for axial movement between an extended position and a retracted position, the pintle having a head portion engageable with the spray aperture to close the spray aperture when the pintle is in its retracted position; biasing means being provided for biasing the pintle towards its retracted position; and solenoid means for selectively moving the pintle into said extended position; said solenoid means comprising an electromagnetic coil and a moveable armature capable of being acted upon by the coil to urge the pintle towards its extended position; wherein the pintle and armature are separable from one another whereby the armature can decouple from the pintle when the pintle moves from its extended position to its retracted position.

Abstract: A fuel injector for an internal combustion engine, the injector comprising an injector body having a tip portion defining at least one spray aperture; a pintle extending within the tip portion, the pintle having a head portion engageable with a valve seat to close the spray aperture, the pintle being axially moveable between a closed position wherein the head portion abuts the valve seat and an open position wherein the head portion is spaced from the valve seat; actuating means for selectively urging the pintle towards its open position; guide means being provided within the injector body guiding the pintle for axial movement between its closed and open positions; a fuel supply chamber being defined within the injector body between the spray aperture and the guide means, characterised in that the diameters of the guide means and valve seat are selected such that the pintle is substantially pressure balanced.