Fuel injection system

Abstract

A fuel injection system has a fuel injection pump (1) having a plunger (1A) disposed in a pressure chamber (1D) and actuatable by a cam (2), and a solenoid-operated valve (6) connected to an injection pipe (4) communicating between the fuel injection pump (1) and a fuel injection nozzle (3), the solenoid-operated valve (6) being disposed near the fuel injection nozzle (3). A controller (C) has an injection advance map and an injection period map both depending on the rotational speed (9) of an engine and the load (10) on the engine. The controller (C) opens and closes the solenoid-operated valve (6) for controlling the supply of fuel from the fuel injection pump (1) to the fuel injection nozzle (3). Since the solenoid-operated valve (6) is disposed near the fuel injection nozzle (3), the fuel can well be cut off when the injection of the fuel is finished, thus reducing HC in exhaust gases and improving fuel economy. The timing to open and close the solenoid-operated valve (6) is controlled by the controller (C) to inject the fuel in an optimum pattern for lowering noise and NOx in the exhaust gases.

Dependencies are inferred from the claim text.