Fuel Injection Valve Control Using Current Fall Timing

The patent inverts the measurement approach by measuring the fall period of excitation current (from peak to reference value) instead of the rise period (from zero to peak). This inversion allows accurate measurement of injection standby period even when energization period is short, because the fall period can be measured more reliably in the decreasing current phase.

The patent uses the fall period of excitation current as a proxy or copy to determine the injection standby period. By measuring the fall period (which is more stable and less affected by detection variations) and using it to infer the standby period, the system achieves accurate measurement without directly measuring the difficult rise period.

The system uses the excitation current itself to measure the injection standby period through timing the fall period, rather than relying on separate detection circuits. The current waveform provides its own measurement information, eliminating the need for complex external detection circuits and their associated precision problems.

The patent replaces physical current detection circuits with a timing-based measurement method. Instead of using complex detection hardware to measure current values, the system uses temporal measurement of when current reaches reference values, substituting mechanical/electrical detection with a timing-based approach that is less sensitive to circuit variations.