VEHICLE ENGINE CONTROL SYSTEM

摘要

A calculation control circuit unit 110A is provided with a microprocessor 111, an auxiliary control circuit unit 190A, and a high-speed A/D converter 115 to which the detection signals of excitation currents for electromagnetic coils 81 through 84 are inputted; based on an valve-opening command signal generated by the microprocessor 111 and excitation-current setting information, the auxiliary control circuit unit 190A opening/closing-controls power supply control opening/closing devices by use of a numeral value comparator and a dedicated circuit unit, and monitors and stores at least one of the peak value of a rapid excitation current and a peak current reaching time; the microprocessor 111 performs correction control with reference to the monitoring storage data, and implements fuel injection control while reducing a rapid control load on the microprocessor 111.

主权项

1. A vehicle engine control apparatus comprising, for sequentially driving respective fuel-injection electromagnetic valves provided on cylinders of a multi-cylinder engine:
an input/output interface circuit unit for two or more groups of electromagnetic coils that drive the electromagnetic valves; a voltage boosting circuit unit that generates a boosted high voltage for rapidly exciting the electromagnetic coils; and a calculation control circuit unit formed mainly of a microprocessor, wherein the two or more groups of electromagnetic coils include at least a first group of electromagnetic coils and a second group of electromagnetic coils, which are two or more groups of electromagnetic coils that perform fuel injection alternately and sequentially among the groups, wherein the input/output interface circuit unit is provided with power supply control opening/closing devices including a first low-voltage opening/closing device that connects the first group of electromagnetic coils with a vehicle battery and a second low-voltage opening/closing device that connects the second group of electromagnetic coils with the vehicle battery, the first and second high-voltage opening/closing devices are connected with the output of the voltage boosting circuit unit, respective selective opening/closing devices separately connected with the electromagnetic coils, and first and second current detection resistors that are connected with the first and second electromagnetic coils, respectively, wherein the calculation control circuit unit is provided with a low-speed multichannel A/D converter, a high-speed multichannel A/D converter, and an auxiliary control circuit unit that collaborate with the microprocessor, wherein low-speed-change analogue sensors including an air flow sensor that detects an intake amount of the multi-cylinder engine and a fuel pressure sensor for injection fuel are connected with the multi-channel A/D converter; and digital conversion data proportional to a signal voltage of each of the sensors is stored in a buffer memory connected with the microprocessor through a bus line, wherein respective analogue signal voltages proportional to the voltages across the first and second current detection resistors are inputted to the high-speed A/D converter; and multi-input-channel digital conversion data pieces obtained by the high-speed A/D converter are stored in a first and second present value registers, wherein the auxiliary control circuit unit includes a first numeral value comparator that compares a value stored in a first setting value register with a value stored in the first present value register and a second numeral value comparator that compares a value stored in a second setting value register with a value stored in the second present value register, first and second high-speed timers and at least one of first and second peak-hold registers, and first and second dedicated circuit units, wherein the first numeral value comparator and the second numeral value comparator compare setting data, that are sent from the microprocessor, preliminarily stored in the first setting value register and the second setting value register, and serve as control constants for excitation currents for the electromagnetic coils, with actually measured data proportional to the present values, of the excitation currents, that are stored in the first and second present value registers; then, the first numeral value comparator and the second numeral value comparator generate a first and second determination logic outputs, wherein in response to the signal voltages, from the air flow sensor and the fuel pressure sensor, that are inputted to the multi-channel A/D converter and the operation of the crank angle sensor, which is one of the opening/closing sensors, the microprocessor determines generation timings and valve-opening command generation periods of the valve-opening command signals for the electromagnetic coils, wherein in response to the valve-opening command signals and the first and second determination logic outputs, the first and second dedicated circuit units generate a opening/closing command signals including a first and second high-voltage opening/closing command signals for the first and second high-voltage opening/closing devices, a first and second low-voltage opening/closing command signals for the first and second low-voltage opening/closing devices, and selective opening/closing command signals for the selective opening/closing devices, wherein the first and second high-speed timers measure and store, as an actually measured reaching time, the time from a time point when the valve-opening command signal is generated and any one of the first and second high-voltage opening/closing devices and the selective opening/closing devices is driven to close to a time point when the excitation current for the electromagnetic coil reaches a predetermined setting cutoff current, wherein the first and second peak-hold registers store, as an actually measured peak currents, the maximum values of the first and second present value registers during a period in which the valve-opening command signals are generated, and wherein the microprocessor is further provided with correction control units that read monitoring storage data, which is the actually measured reaching time or the actually measured peak current, that monitor a generation state of the rapid excitation current, and that adjust setting data for the first and second setting value registers or a valve-opening command generation period of the valve-opening command signal in such a way that the amount of fuel injection by the fuel-injection electromagnetic valve becomes a desired value.