Patent ID: 7263974
Filing Date: 2007-09-04
Classification: F02M

Abstract:
1. A fuel injection system for supplying pressurised fuel to a fuel injector, the fuel injection system comprising: an accumulator volume for supplying fuel at rail pressure to the fuel injector through a rail fuel supply passage; a fuel pressurising arrangement for supplying fuel at a selected pressure greater than rail pressure to the fuel injector through a pressurised fuel supply passage; a rail control valve operable between a restricted-flow position in which the flow of fuel from the fuel pressurising arrangement to the accumulator is reduced relative to the flow rate at an open position in which fuel from the accumulator volume is permitted to flow more freely from the fuel pressurising arrangement to the accumulator; and a fuel shut-off valve operable during an injection of fuel from the rail fuel supply passage between a closed position in which fuel is retained within the pressurising arrangement and an open position in which pressurised fuel is supplied to the injector from the pressurising arrangement, thereby to provide a boost in the fuel pressure delivered during an injection event.