| 摘要 |
<p>A fuel injector for use in delivering fuel to an internal combustion engine comprises a nozzle having a valve needle which is moveable with respect to a valve needle seating through a range of movement between a fully-closed position and a fully-open position to control fuel delivery through at least one nozzle outlet, whereby movement of the nozzle needle is controlled by fuel pressure within a control chamber (18). A nozzle control valve (10, 32a, 32b) controls fuel flow into and out of the control chamber (18) to pressurise and depressurise the control chamber, respectively. The fuel injector further comprises a variable flow passage means (52, 44, 46) in communication with the control chamber (18) through which fuel flows out of the control chamber (18) at a variable rate throughout the range of movement of the valve needle so that movement of the valve needle is damped to a greater extent as it approaches the fully-open position.</p> |
