Fuel injection control apparatus
AssigneeDenso Corporation
InventorToshio Nishimura
Life of this patent
Estimating the term…
Abstract
In a fuel injection control apparatus, an injector is driven to open its valve by supplying a coil of the injector with a current during a high-level period of a power supply command signal outputted from a microcomputer. A valve-closing time of the injector is detected based on a coil current, which decreases from a fall time of the power supply command signal. By comparing the coil current with plural equally-divided comparison threshold values by comparators, times are detected when the coil current decreases to the comparison threshold values, respectively. The valve-closing time is detected based on time differences among the detected times.
Claims12
A fuel injection control apparatus for an injector having a coil and a valve, the fuel injection control apparatus comprising:
- a setting part for setting a drive period of the injector;
- a drive control part for driving the injector to open the valve by starting a power supply operation of supplying a power voltage to the coil of the injector to supply a current to the coil at a start time of the drive period set by the setting part, and for stopping the power supply operation to close the valve at an end time of the drive period;
- a detection part for detecting a valve-closing time of the injector based on the coil current, which decreases from the end time of the drive period, wherein:
- the detection part detects, after the end time of the drive period and by sequentially comparing the coil current with each of plural comparison threshold values, each time that the coil current decreases to each of the plural comparison threshold values, and detects the valve-closing time based on detected times, and
- the plural comparison threshold values are provided for comparison with the coil current after the end time of the drive period.
Dependencies are inferred from the claim text.