Fuel Injector Opening State Detection via Magnetic Flux

The patent extracts the specific signal components corresponding to needle opening and closing events from the complex eddy current signal. By identifying and isolating the characteristic signal features (voltage peaks) that correspond to these events, the method separates the useful timing information from the complex background signal, thereby improving measurement precision without requiring complex overall signal processing.

The patent replaces direct mechanical timing detection with electrical signal analysis. Instead of using mechanical switches or physical sensors on the moving parts, the invention uses electrical measurement of eddy current effects in the magnetic circuit to detect timing events, simplifying the physical detection system while maintaining measurement capability.

The patent performs preliminary identification of the characteristic signal features corresponding to needle opening and closing events. By pre-establishing what the timing signals look like and where to look for them in the eddy current signal, the system can quickly extract timing information without extensive post-processing, thus maintaining injection consistency while minimizing data processing time.

The eddy current signal itself provides the timing information needed - the signal changes naturally occur at the moments of needle opening and closing. The system uses the signal's own characteristics (voltage peaks at specific events) to determine timing, eliminating the need for separate measurement systems or complex external processing.