JPH0778378B2 - Fuel injection cylinder discrimination device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fuel injection cylinder discrimination device capable of accurately discriminating a cylinder injecting fuel.

[Prior Art] An automobile engine is mainly composed of an internal combustion engine in which a fuel-air mixer is exploded and burned in a cylinder, and combustion energy at that time is used as propulsion power. In this type of internal combustion engine, the supply timing of the air-fuel mixture, the exhaust gas timing of the exhaust gas, the ignition timing of the air-fuel mixture, etc., are important factors that are indispensable for improving fuel efficiency. Electronic fuel injection control devices have been actively introduced. In this type of electronic fuel injection control device, fuel consumption can be reduced by an irregular use such as using a 6-cylinder engine with only 4 cylinders, and a fuel-injection cylinder discrimination device for discriminating a fuel-injecting cylinder is indispensable. is there.

The conventional fuel injection cylinder discrimination device 1 shown in FIG. 3 is connected to a fuel injection control device 2 which supplies a valve opening signal as a fuel injection command to a fuel injection valve of a 6-cylinder engine. A ring counter is formed by connecting six flip-flop circuits F1 to F6 whose set input terminals are connected to the output terminals 2a to adjacent reset input terminals and set input terminals. The Q output terminals of each of the flip prop circuits F1 to F6 are connected to the central processing unit 3 which is the center of the fuel injection control.

[Problems to be Solved by the Invention] The conventional fuel injection cylinder discrimination device 1 described above is suitable when the vehicle is traveling at a low speed, but when the vehicle starts traveling at a high speed, the interval between the valve opening signals is gradually narrowed. Finally, as shown in FIG. 4, the valve opening signals of adjacent cylinders partially overlap each other in the same time zone, and as a result, the adjacent flip-flop circuits F1 and F2 or F2 and F3. Since the set input and the reset input are supplied to .. etc. at the same time, the reset may not be applied to any of the flip-flop circuits F1 to F6. In this case, since the flip-flop circuits F1 to F6 are still set, the central processing unit 3 cannot accurately determine which cylinder is injecting fuel, and the fuel injection control itself falls into a malfunction, resulting in a decrease in fuel consumption. There were problems such as the inability to maintain economical driving.

[Means for Solving the Problems] The present invention solves the above problems, and differentiates the fuel injection command supplied to each cylinder of an internal combustion engine having a plurality of cylinders in a fixed order with respect to time. However, multiple edge detection circuits that detect the rising edge of each fuel injection command and the edge detection output of the fuel injection command to the reference cylinder are reset, and all the edge detection outputs of other edge detection circuits are clock signals. And a counting circuit that performs a counting operation.

[Operation] According to the present invention, the fuel injection command supplied to a plurality of cylinders in a fixed order is time-differentiated, the rising edge portion of each fuel injection command is detected, and the fuel injection command to the reference cylinder is also detected. By counting the edge detection output of the fuel injection command to other cylinders as a clock signal, the counting circuit that is reset by the edge detection output of
Counting is performed with the same number as the number of cylinders, and the count output of the counting circuit directly corresponds to the fuel injection cylinder.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a circuit configuration diagram showing an embodiment of the fuel injection cylinder discrimination device of the present invention, and FIG. 2 is a signal waveform diagram of each part of the circuit shown in FIG.

In FIG. 1, a fuel injection cylinder discriminating apparatus 11 detects a rising edge by differentiating a valve opening signal as a fuel injection command supplied from the fuel injection control apparatus 2 as a fuel injection command to detect a rising edge. ~ E6 and the output of the edge detection circuit E1 corresponding to the reference cylinder among the outputs of these edge detection circuits E1 to E6 is the reset input, while the other edge detection circuits E2 to E6 are the clock input, It is composed of a counting circuit 12 that performs counting with the same number of decimals as the number, and the counting output terminals Q0, Q1, Q2 of the counting circuit 12 are connected to the data input terminal of the central processing unit 3. Edge detection circuit E1 ~
E6 is a differential capacitor C in series with the signal line,
Edge detection is made up of a resistor R branched and connected to the signal line, and a diode D that rectifies and outputs a positive-going rising edge pulse of the signal that has passed through the differential capacitor C and at the same time prevents the signal from sneaking in from other circuits. The diodes D of the edge detection circuits E2 to E6 other than the circuit E1 are commonly connected to the clock input terminal of the counting circuit 12.

The valve opening signal, which is the output of the fuel injection control device 2, is time-differentiated by the differential capacitor C in each of the edge detection circuits E1 to E6, and then rectified and output by the diode D.
As shown, only the rising edge portion of each valve opening signal is supplied to the counting circuit 12. Therefore,
After being reset by the edge portion of the valve opening signal corresponding to the reference cylinder, the counting circuit 12 repeats the hexadecimal counting operation by using the valve opening signal for another cylinder as a clock. That is, from the counting output terminals Q1, Q2, Q3 of the counting circuit 12, (000), (0
01, (010), (011), (100), (101), etc. 2
The hexadecimal count output displayed in a decimal number is supplied to the central processing unit 3. In this case, since only the edge portion of each valve opening signal is taken out as information, even if the engine rotates at high speed, the clock inputs of the counting circuit 12 do not overlap each other in the same time zone, and therefore the fuel is always accurately and accurately fed. It is possible to determine the injection cylinder.

In this way, the fuel injection cylinder discrimination device 11 temporally differentiates the fuel injection command supplied to a plurality of cylinders in a fixed order, detects the rising edge portion of each fuel injection command, and serves as a reference. The counting circuit 12 reset by the edge detection output of the fuel injection command to the cylinder,
By performing the counting operation using the edge detection output of the fuel injection command to the other cylinders as a clock signal, the counting is executed with the same number as the number of cylinders, and the counting output of the counting circuit 12 directly corresponds to the fuel injection cylinder. Therefore, even during the high-speed operation in which the fuel injection interval is narrowed, the counting circuit 12 that uses the rising edge of the fuel injection command as the reset input and the clock input can surely perform the counting operation with the same advance number as the number of cylinders. Moreover, since the counting output of the counting circuit 12 coincides with the number of the fuel injection cylinder counted from the reference cylinder as it is, the data processing in the central processing unit 3 etc. provided after the counting circuit 12 can be easily advanced. You can

In the above embodiment, when only 4 cylinders out of 6 cylinders are used, the counting circuit 12 supplies the quaternary count output to the central processing unit 3.

[Effects of the Invention] As described above, according to the present invention, the fuel injection command supplied to a plurality of cylinders in a fixed order is time-differentiated, the rising edge portion of each fuel injection command is detected, and the reference The counter circuit that is reset by the edge detection output of the fuel injection command to the cylinder that becomes is the counting operation using the edge detection output of the fuel injection command to other cylinders as the clock signal, so that the number of cylinders is the same as the number of decimals. Since the counting is performed and the counting output of the counting circuit is made to directly correspond to the fuel injection cylinder, even when the fuel injection interval is narrowed and the high speed operation is performed, the rising edge of the fuel injection command is used as the reset input and the clock input. The circuit can reliably perform counting operation with the same number of cylinders as the number of cylinders, and the counting output of the counting circuit can be used as a reference as it is. Since it corresponds to the number of the fuel injection cylinder counted from the above, there is an excellent effect that the data processing in the central processing unit or the like provided in the latter stage of the counting circuit can be easily advanced.

[Brief description of drawings]

FIG. 1 is a schematic circuit configuration diagram showing an embodiment of a fuel injection cylinder discrimination device of the present invention, FIG. 2 is a signal waveform diagram of each part of the circuit shown in FIG. 1, and FIG. 3 is a conventional fuel. FIG. 4 is a schematic circuit configuration diagram showing an example of the injection cylinder discrimination device, and FIG. 4 is a signal waveform diagram of each part of the circuit shown in FIG. 11 …… Fuel injection cylinder discrimination device, 12 …… Counting circuit, E1 to E6…
… Edge detection circuit.

Claims (1)

[Claims] 1. A plurality of edge detection circuits for time-differentiating a fuel injection command supplied to each cylinder of an internal combustion engine having a plurality of cylinders in a fixed order to detect a rising edge portion of each fuel injection command. , A fuel injection cylinder comprising a counting circuit which is reset by the edge detection output of the fuel injection command to the reference cylinder and which counts all the edge detection outputs of other edge detection circuits with the same number of cylinders as the clock signal. Discriminator.