FUEL INJECTION APPARATUS

摘要

A fuel injection system is proposed which serves to adapt the fuel-air mixture as precisely as possible to operating conditions of the internal combustion engine. The fuel injection system includes metering valves, each of which is assigned a regulating valve whose movable valve element can be exposed on one side to the fuel pressure downstream of the respective metering valve and on the other side to a control pressure line defined on one end by a control pressure valve of the nozzle/impact plate type and on the other end by a control throttle. The control pressure valve has a permanent magnet and an electromagnet, the magnetic fluxes of which are guided via an armature in such a manner that in at least one air gap the magnetic fluxes of the permanent magnet and of the electromagnet extend in the same direction, while in at least one other air gap the magnetic fluxes of the permanent magnet and of the electromagnet extend in opposite directions. This kind of embodiment requires a substantially smaller triggering power on the part of the electromagnet. By reversing the exciter current of the electromagnet, the control pressure valve is opened widely enough that the control pressure engaging the regulating valves causes the closure of the regulating valves, and the injection of fuel is precluded.