JP3827840B2 - Ignition control device for internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ignition control device for an internal combustion engine.
[0002]
[Prior art]
FIG. 8 shows an outline of a conventional ignition control device for an internal combustion engine. In FIG. 8, reference numeral 1 denotes a coil igniter, and the coil igniter 1 includes an ignition coil 3 including a primary coil 2a and a secondary coil 2b, an igniter unit 4, and the like. Reference numeral 5 denotes a terminal for supplying a power supply voltage to the ignition coil 3, and one end of the primary coil 2a and the secondary coil 2b is connected thereto. The other end of the primary coil 2 a is connected to a switching power transistor of the igniter unit 4. An internal combustion engine control circuit 6 applies an energization signal from the control circuit 6 to the igniter section 4 of the coil igniter 1. Reference numeral 7 denotes an ignition plug, to which the other end of the secondary coil 2b of the ignition coil 3 is connected and a high voltage is applied.
[0003]
In FIG. 8, when an energization signal is applied from the control circuit 6 to the coil igniter 1, the power transistor of the igniter unit 4 is turned on and off, and energization to the primary coil 2a is controlled. At the moment when the energization of the primary coil 2 a is cut off, a high voltage is generated in the secondary coil 2 b, and this high voltage is applied to the spark plug 7, and a spark is generated in the spark plug 7.
[0004]
FIG. 9 shows another example of a conventional ignition control device having an ion detection function. In this configuration, an ion waveform processing circuit 8 is added to the configuration of FIG. 8, and the low voltage side of the secondary coil 2 b is connected to the ion waveform processing circuit 8 and controlled by the control circuit 6. After a spark is generated in the spark plug 7, ions are normally generated in the engine combustion chamber. Thereby, since an impedance change occurs in the gap of the spark plug 7, it is detected and processed by the ion waveform processing circuit 8 connected to the low voltage side of the secondary coil 2b connected to the ground or + B, An ignition misfire detection signal and a knock detection signal are output to the control circuit 6.
[0005]
Thus, even in the past, ignition misfire detection and knock detection are possible with the ignition control device, and intelligentization is rapidly progressing, but with that, the number of output pins for detection signals also increases, space, Problems such as increased noise due to an increase in cost and the number of harnesses occur. This is a serious problem particularly in an ignition control device in which a coil igniter is arranged for each cylinder. For example, in the case of a system in which two signals are detected by one cylinder and output to the control circuit 6, as shown in FIG. 10, the detection signal is supplied to the three pins for power supply, ground, and input signal for each ignition control circuit. Since 2 pins are added for, it becomes 5 pins. When it is a 4-cylinder cylinder, it has a total of 20 pins, and when it is a 6-cylinder cylinder, it has a total of 30 pins.
[0006]
[Problems to be solved by the invention]
The present invention solves the above-described conventional problems, and an object thereof is to provide a low-cost ignition control device that has a simple configuration, a small number of terminals (pins), and a low cost.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises detection signal generating means for detecting the presence / absence of ignition / misfire and knock from an ion current or impedance change, and generating a detection signal of a level corresponding to the detection result, The signal is extracted by connecting two transistors connected to the ignition / misfire detection means and the knock presence / absence detection means in parallel with these transistors, and connecting the connection point of the transistor to the output terminal. that it is characterized in the TURMERIC lines through a simple configuration of the detection signal output means having a two-dividing resistors, a single two detection signals of ignition and misfire and knocking outputted from the detection signal generating means Output from the signal line, the configuration is simple and the number of terminals (number of pins) can be reduced, the coil igniter is downsized and the cost is reduced. And noise reduction is possible by being able to reduce the number of harness.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
According to a first aspect of the present invention, a voltage generating means for generating a high voltage to be applied to the spark plug and an ion current or impedance change generated between the electrodes of the spark plug at the time of ignition are detected. ignition and misfire and to detect the presence or absence of knocking, the ignition control system for an internal combustion engine that includes a detection signal generation means for output the detection signal, the detection signal generating means, occurs between the electrodes of the spark plug Ignition / misfire detection means for detecting ignition / misfire by detecting changes in ion current or impedance, and knock presence / absence detection means for detecting presence / absence of knock from the change in ion current or impedance detected between the electrodes of the spark plug And a detection signal of a level corresponding to the detection results of the ignition misfire detection means and the knock presence / absence detection means. Detection signal output means for outputting a signal from a single signal line, wherein the detection signal output means is a first transistor that is turned on / off by the output of the ignition misfire detection means, and a first transistor between a power supply voltage and ground. A second transistor connected in series with the first transistor, and turned on and off by the output of the knocking presence / absence detecting means, in parallel with these transistors, and connected to the connecting portion of these transistors and connected to the output terminal. An ignition control device for an internal combustion engine, comprising: a first and a second voltage dividing resistor connected to each other , wherein a detection signal for detecting the presence / absence of ignition / misfire and knocking comprises two transistors and a partial pressure since the output from the single signal line via the detection signal output means having a resistance, be configured at a low cost is simplified, reducing the terminal and the number of harness Kill.
[0011]
The invention described in claim 2 of the present invention, the ignition timing adjustment means for adjusting the ignition timing in the voltage generating means based on a detection signal output from said detection signal generating means, to the ignition timing adjustment means 2. An ignition control apparatus for an internal combustion engine according to claim 1, further comprising a control means for outputting a signal for determining ignition timing, wherein the detection signal for detecting the presence / absence of ignition / misfire and knocking is adjusted through a single signal line. Since it is output to the means, it is only necessary to input the ignition timing signal from the control means, the configuration is simplified, and the number of terminals and harnesses can be reduced.
[0012]
The invention described in claim 3 of the present invention, the ignition timing adjustment means, wherein determining the presence or absence of ignition and misfire and knocking by detecting the level of the detection signal after the different time from the point of ignition timing Item 2. The ignition control device for an internal combustion engine according to Item 2 , wherein the presence or absence of ignition / misfire and knocking can be easily and quickly determined.
[0017]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 shows the configuration of an ignition control device for an internal combustion engine according to a first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes a coil igniter, which includes an ignition coil 13 including a primary coil 12a and a secondary coil 12b and an igniter section 14 constituting voltage generating means. Reference numeral 15 denotes a terminal for supplying a power supply voltage to the ignition coil 13, and one end of the primary coil 12a is connected thereto. The other end of the primary coil 12a is connected to a switching power transistor of the igniter section 14. Reference numeral 16 denotes a control circuit for the internal combustion engine, and an energization signal is applied from the control circuit 16 to the igniter section 14 of the coil igniter 11. Reference numeral 17 denotes an ignition plug, to which the other end of the secondary coil 12b of the ignition coil 13 is connected and a high voltage is applied. Reference numeral 18 denotes an ion waveform processing circuit as detection signal generating means, which is connected to the low voltage side of the secondary coil 12b and outputs the detected detection signal from one output terminal.
[0018]
FIG. 2 shows the internal configuration of the ion waveform processing circuit 18. In FIG. 2, 20 is an input terminal, and this input terminal 20 is connected to one end of the secondary coil 12b. Reference numeral 21 denotes an integration circuit, and reference numeral 22 denotes a comparator, which constitutes an ignition misfire detection means. After the ion current applied to the input terminal 20 is integrated by the integration circuit 21, the comparator 22 compares the current with a predetermined value. Ignition signal / misfire signal can be obtained. Reference numeral 23 denotes a band pass filter, 24 denotes an integration circuit, and 25 denotes a comparator, which constitutes a knock presence / absence detection means. After the ion current applied to the input terminal 20 is passed through the high frequency component by the band pass filter 23, The high frequency component is integrated by the integrating circuit 24, and this integrated value is compared with a predetermined value by the comparator 25, thereby obtaining a knocked / no knocked signal. Reference numerals 26 and 27 denote transistors, which together with the resistors 28, 29, and 30 constitute detection signal output means. The output of the comparator 22 is applied to the base of the transistor 26. When there is a misfire, the transistor 26 is turned on, and when there is no misfire, the transistor 26 is turned off. The output of the comparator 25 is applied to the base of the transistor 27. When the knock is present, the transistor 27 is turned on. When the knock is absent, the transistor 27 is turned off. Reference numerals 29 and 30 denote voltage dividing resistors, and each connection point is connected to a connection point between the transistors 26 and 27 and connected to the output terminal 31.
[0019]
3A shows an igniter input signal, and FIGS. 3B, 3C, and 3D show waveforms of ion currents obtained between the electrodes of the spark plug 17. FIG. 3B is a waveform when ignition occurs, FIG. 3C is a waveform when knocking occurs, and FIG. 3D is a waveform when misfire occurs.
[0020]
FIG. 4 is a timing chart for explaining the operation of the ion waveform processing circuit 18. 4A is an igniter input waveform, FIG. 4B is an output waveform diagram of the ion waveform processing circuit 18 that is ignited and without knocking, and FIG. 4C is an output waveform of the ion waveform processing circuit 18 that is misfired and has no knocking. FIG. 4 (D) is an output waveform diagram of the ion waveform processing circuit 18 with ignition and knocking, and FIG. 4 (E) is an output waveform diagram of the ion waveform processing circuit 18 with knocking and knocking.
[0021]
Hereinafter, the operation in the present embodiment will be described. When a spark is generated in the spark plug 17 at the falling timing of the igniter input signal (FIG. 4A) and ignition does not cause knocking, the transistor 26 in FIG. 2 is turned off and the transistor 27 is also turned off. The voltage (Vout) of the output terminal 31 is 2.5 V (the resistance values of the resistors 29 and 30 are the same) with respect to the power supply voltage (5 V) (FIG. 4B).
[0022]
Next, when spark is generated in the spark plug 17 at the timing of the fall of the igniter input signal, misfire and knock does not occur, the transistor 26 is turned on, the transistor 27 is turned off, and the voltage at the output terminal 31 (Vout) Becomes substantially the same voltage (5V) as the power supply voltage (5V) (FIG. 4C).
[0023]
When a spark is generated in the spark plug 17 at the timing of the fall of the igniter input signal and the ignition is generated, but the knock occurs, the transistor 26 is turned off, the transistor 27 is turned on, and the voltage of the output terminal 31 (Vout) Becomes the ground voltage (0 V) (FIG. 4D).
[0024]
Further, when a spark is generated in the spark plug 17 at the timing of the fall of the igniter input signal, misfire and knocking occur, the transistor 26 is turned from OFF to ON, the transistor 27 is also turned from OFF to ON, and the output terminal 31 The voltage (Vout) changes from 5 V to 0 V over time (FIG. 4E).
[0025]
In this way, the signals shown in FIGS. 4B, 4C, 4D, and 4E are input to the control circuit 16, and therefore, after the elapse of t1, t2 from the ignition timing t0 in the control circuit 16, By detecting the voltage, the presence / absence of ignition / misfire and the presence / absence of knock can be detected.
[0026]
As described above, according to the first embodiment, by outputting the output from the ion waveform processing circuit 18 to the control circuit 16 through a single signal line (pin), the control circuit 16 is ignited / misfired and knocked. As shown in FIG. 5, it is only necessary to add one pin for the detection signal in addition to the power supply, the ground, and the input signal to the terminal (pin) of the coil igniter 11, as shown in FIG. Can be reduced.
[0027]
(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIG. For convenience of explanation, reference numerals used in FIG. 1 are used for similar components. In the first embodiment, the control circuit 16 controls the ignition timing. However, in the second embodiment, the ignition timing adjusting circuit 19 is provided in the coil igniter 11, and only the ignition timing signal is transmitted from the control circuit 16. And the ignition timing is adjusted in the coil igniter 11 based on the ignition / misfire and knock detection signals detected by the ignition timing adjustment circuit 19.
[0028]
FIG. 7 is a diagram showing the operation timing in the present embodiment. In FIG. 7, at the normal time, that is, when the output of the ion waveform processing circuit 18 is 2.5 V (FIG. 7B), the ignition timing signal (FIG. 7A) is sent from the control circuit 16 to the ignition timing adjustment circuit 19. From there, a normal igniter input signal (FIG. 7C) is sent to the igniter section 14. At the time of misfire, that is, when the output of the ion waveform processing circuit 18 is 5 V (FIG. 7D), an ignition timing signal (FIG. 7A) is sent from the control circuit 16 to the ignition timing adjustment circuit 19, from which An igniter input signal is not sent to the igniter section 14 (FIG. 7E). When knocking occurs, that is, when the output of the ion waveform processing circuit 18 is 0 V (FIG. 7 (F)), an ignition timing signal (FIG. 7 (A)) is sent from the control circuit 16 to the ignition timing adjusting circuit 19, but there To the igniter section 14 is sent an igniter input signal (FIG. 7G) with a delayed ignition timing.
[0029]
As described above, in the second embodiment, the ignition timing adjusting circuit 19 provided in the coil igniter 11 detects the voltage after the elapse of t1, t2 from the ignition timing t0, thereby determining whether or not ignition / misfire has occurred. The presence or absence of knocking can be detected, and only the ignition timing signal is applied from the control circuit 16 to the coil igniter 11, so that the detection signal terminal required in the first embodiment is also unnecessary, and The number of terminals and harnesses can be reduced.
[0030]
【The invention's effect】
As is clear from the above embodiment, the present invention is configured to connect a plurality of detection signals in parallel to two transistors connected to the ignition misfire detection means and the knock presence / absence detection means, and to these transistors in parallel. Since the detection signal output means having two voltage-dividing resistors connected to the output terminal and connected to the output terminal can be output through a single signal line, the configuration is simplified, and the coil igniter There is an advantage that noise can be reduced by downsizing, cost reduction, and reduction in the number of harnesses.
[Brief description of the drawings]
FIG. 1 is a block diagram of an ignition control device for an internal combustion engine according to Embodiment 1 of the present invention. FIG. 2 is an electric circuit diagram of an ion waveform processing circuit according to Embodiment 1 of the present invention. FIG. 4 is a timing diagram for explaining the operation in the first embodiment of the present invention. FIG. 5 is a terminal structure of the coil igniter in the first embodiment of the present invention. FIG. 6 is a block diagram of an ignition control device for an internal combustion engine according to a second embodiment of the present invention. FIG. 7 is a timing diagram for explaining an operation according to the second embodiment of the present invention. FIG. 9 is a block diagram of another ignition control device of a conventional internal combustion engine. FIG. 10 is a schematic diagram showing a terminal structure of a conventional coil igniter.
DESCRIPTION OF SYMBOLS 11 Coil igniter 12a Primary coil 12b Secondary coil 13 Ignition coil 14 Igniter part 15 Power supply terminal 16 Control circuit 17 Spark plug 18 Ion waveform processing circuit 19 Ignition timing adjustment circuit 20 Input terminal 21 Integration circuit 22 Comparator 23 Band pass filter 24 Integration Circuit 25 Comparator 26, 27 Transistor 28, 29, 30 Resistor 31 Output terminal

Claims (3)

Detecting the presence / absence of ignition / misfire and knock by detecting a change in the ionic current or impedance generated between the electrodes of the spark plug during ignition and a voltage generating means for generating a high voltage to be applied to the spark plug, the ignition control system for an internal combustion engine that includes a detection signal generation means for output the detection signal,
The detection signal generating means detects an ignition / misfire by detecting a change in ion current or impedance generated between the electrodes of the spark plug, and an ion current detected between the electrodes of the spark plug. Alternatively, a knock presence / absence detecting means for detecting the presence / absence of knock from the change in impedance, and a detection signal of a level corresponding to the detection result of the ignition misfire detection means and the knock presence / absence detection means are generated, and this detection signal is sent to a single signal line. Detection signal output means for outputting from,
The detection signal output means is connected in series with the first transistor that is turned on and off by the output of the ignition misfire detection means, and between the power supply voltage and the ground, and by the output of the knock presence / absence detection means A second transistor that is turned on and off; and first and second voltage-dividing resistors that are connected in parallel to the transistors and connected to the output terminals by connecting the connecting portions to the connecting portions of the transistors. An internal combustion engine ignition control device. It includes an ignition timing adjusting means for adjusting the ignition timing in the voltage generating means based on a detection signal output from said detection signal generating means, and control means for outputting a signal for determining the ignition timing to the ignition timing adjustment means The ignition control device for an internal combustion engine according to claim 1. The ignition control device for an internal combustion engine according to claim 2, wherein the ignition timing adjusting means determines the presence / absence of ignition / misfire and knock by detecting the level of a detection signal after a lapse of a different time from the ignition timing.

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