Nozzle Holder Combination

Design
(e.g. Lucas)


Task
Combining injection nozzle and nozzle holder.

Function
The compression spring (51/4) in the retaining body (51/5) applies pressure on the nozzle needle (50/2) through the pressure pin (51/2). The preload of the compression spring (51/4), which can be altered by the thickness of the shim (51/7), determines the opening pressure of the fuel injection nozzle. Fuel flows to the seat of the injection nozzle through the feed drilling (51/8) in the retaining body (51/5), intermediate disc (51/5) and nozzle body (50/3).

During fuel injection, the nozzle needle (50/2) lifts off from its seat when the opening pressure of the injection nozzle is reached and fuel is injected through the annular gap at the throttling pintle in a finely atomized spray into the prechamber. After the fuel pressure drops below the opening pressure of the injection nozzle, the compression spring (51/4) pushes the nozzle needle (50/2) back onto its seat.