Fuel injection for IC engine

摘要

The fuel injection valve is operated by solenoids and has permanent magnet holds for at least one of the valve settings. The complete valve design has two solenoid coils (34, 36) to open and close the valve and two permanent magnets (52, 54) to hold the valve in the open and closed positions. The valve is switched by current pulses in the solenoids for rapid response. In place of the permanent magnets a residual magnetic system can be used, charged by the action of the solenoids. The valve action has at least two cycles for each injection pulse, with one of the pulses shorter than the other. The spatial ratios of the pulses can be varied to control the amount of fuel injected. The vale includes a return duct for excess fuel.