Pump Injectors

Function

The pump injectors enable injection pressures of more than 2000 bar, because high-pressure injection pipes are no longer necessary. Furthermore, it is possible to control electronically the injection without uncontrollable pressure waves and sudden increases in volume due to the pipe system. The hydraulic efficiency increases.

How it works

The pump injector technic has basically three elements: a pump, a very fastly switching electrical high-pressure magnetic valve (see picture to the right) and a hole-type nozzle.The Diesel fuel is delivered from the tank via the fuel heater and the filters directly to the single pumps inside the cylinder head.The magnetic valve closes the pump chamber for the beginning of the delivery and opens it up towards the return pipe at the end of the delivery.The engine-camshaft produces the high pressure via mechanical valves in the pump injectors of every single cylinder.

Disadvantage

The injection system has to be integrated more strongly into the design of the engine than with other systems.

Future

The injection pressure is supposed to increase even more, the injection will have even more cycles, and the elements will become smaller.