Using the signals of the sensors in the characteristics zone, determine the injection amount and the beginning of fuel delivery. Store the errors and substitute the missing or implausible signals in a dry-run operation. Using a workshop test, show the measured values and/or make possible the test of single actuators.
The regulation of the inline injection pump encompasses two areas: the amount and the injection begin control.
Amount control: Through the transducer in the accelerator pedal the control device registers the desired engine power. At the same time, an inductive pickup informs a gear-tooth disc on the camshaft of the inline injection pump, about the engine RPMs. From these and other signals, e.g., from the coolant and fuel temperature, the control device determines the correct injection amount. Through a servo-motor it pushes the control rod into the calculated position. Nominal and, actual values are continually compared with each other and the control rod is shifted accordingly.
Injection begin control: From the signals of the inductive pickup (e.g., the position of the crankshaft), and the accelerator pedal transducer (load) among others, a value for the fuel injection start is determined. Through a servo-motor all cylinders of the single pump elements are shifted vertically at the same time so far that the pistons on their way to TDC seal the fuel inlet passage (beginning of delivery) at the calculated point. The needle motion sensor in the nozzle reports the actual fuel injection start. This is compared to the predetermined nominal value and the stroke of the pump cylinder is accordingly corrected.
Inductive pick-up (position of the crankshaft, engine speed), accelerator pedal transducer (load), temperature sensor (coolant, fuel), needle motion sensor (fuel injection start), air amount, air-mass flow meter or pressure sensors in the inlet manifold (in charged engines).
Servo-motors for control-rod and pump cylinder, electric switch-off device. 05/10