JPH0476036B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an ignition device for an internal combustion engine that has an advance function and a retard function. [Prior Art] In an internal combustion engine, the ignition position is generally advanced in the medium to high speed range of the engine, but in a two-stroke internal combustion engine, it is necessary to retard the ignition position in the high speed range of the engine. . Also, in a 4-stroke engine, to prevent overspeeding of the engine,
It is necessary to retard the ignition position when the engine is running at high speed. In this way, in order to advance the ignition position in the medium-high speed range of the engine and retard the ignition position in the high-speed range, an ignition system for internal combustion engines that has both advance and retard functions is required. do. In a conventional ignition system for an internal combustion engine that has both an advance angle function and a retard angle function, for example, there is a signal coil that outputs a signal at the maximum advance angle position and a minimum advance angle position (maximum retard position) of the engine, respectively. , a first integrating circuit that performs an integral operation by charging a capacitor from the maximum advance angle position to the minimum advance angle position detected by the output of the signal coil; A second integrating circuit that performs an integrating operation by charging the first integrating circuit, and a comparison circuit that compares the output of the first integrating circuit and the output of the second integrating circuit are provided, so that the output of the first integrating circuit is Advance characteristics are obtained by outputting a signal to determine the ignition position when the output exceeds the output of the integrating circuit. Also, an integral operation in which the capacitor is charged with a first current from the minimum advance angle position to the maximum advance angle position, and then the capacitor is additionally charged with a second current larger than the first current from the maximum advance angle position to the minimum advance angle position. A third integrator circuit that performs the following and a comparison circuit that compares the output of the third integrator circuit with a reference voltage is provided, so that the output voltage of the third integrator circuit becomes equal to or higher than the output voltage of the first integrator circuit. Retard characteristics are obtained by outputting a signal to determine the ignition position when the ignition position is reached. [Problems to be Solved by the Invention] The third integral circuit provided to obtain the retard characteristic in the conventional ignition system for an internal combustion engine described above has a function of determining the interval from the minimum advance angle position to the maximum advance angle position and the maximum advance angle position. In addition to the need to charge the capacitor with different charging currents in the section from the angle position to the minimum advance position,
Since a reset circuit is required to discharge the capacitor, the circuit configuration inevitably becomes complicated. An object of the present invention is to provide an ignition device for an internal combustion engine that can have a retardation function with a simple configuration. [Means for Solving the Problems] The present invention provides an ignition circuit that suddenly changes the primary current of an ignition coil through the operation of a semiconductor switch to generate a high voltage for ignition on the secondary side of the ignition coil; A first signal that is at least a threshold level at a first rotational angular position of the engine, and a second signal that is at least the threshold level at a second rotational angular position whose phase is delayed from the first rotational angular position. a signal coil that generates a signal; and an ignition position that receives the first and second signals and generates an ignition signal for operating the semiconductor switch between a first rotational angular position and a second rotational angular position. In an ignition device for an internal combustion engine equipped with a control circuit, a retardation function can be provided with a simple configuration. Therefore, in the present invention, the above-mentioned ignition position control circuit is constituted by the following elements. (b) Initial integration operation of initially charging the first integrating capacitor from the first rotational angular position until the terminal voltage of the first integrating capacitor reaches the set voltage, and additionally charging the first integrating capacitor to a voltage higher than the set voltage. a first integrating circuit that performs an additional integrating operation; (b) A second integrating circuit that performs an integrating operation to charge the second integrating capacitor from each second rotational angular position at a constant time constant. C. The first integrating capacitor obtained at both ends of the first integrating capacitor
and the second integrated voltage obtained across the second integrating capacitor, and when the first integrated voltage is less than or equal to the second integrated voltage, the output terminals are substantially short-circuited and the second integrated voltage is obtained across the second integrating capacitor. 1 integrated voltage is the second
A comparator circuit that effectively cuts off between the output terminals when the integrated voltage exceeds the voltage. A third integrating circuit that performs an integrating operation of charging a third integrating capacitor connected in parallel between the output terminals of the comparator circuit at a constant time constant. E The third voltage obtained across the third integrating capacitor
A circuit that outputs the ignition signal when the integrated voltage of the circuit reaches a predetermined level or higher. (f) A reset circuit that discharges the first and second integral capacitors between the position where the third integral voltage exceeds the reference voltage and the second rotation angle position. [Operation of the Invention] In the above configuration, the position where the first integrated voltage exceeds the second integrated voltage advances as the engine speed increases. Therefore, the position where the potential at the output terminal of the comparator circuit becomes high level advances as the rotational speed increases. Furthermore, when the first integrated voltage is lower than the second integrated voltage, the output terminals of the comparator circuit are substantially short-circuited, so the third integrating capacitor is short-circuited, and the integrating operation of the third integrating circuit is not performed. However, when the first integrated voltage exceeds the second integrated voltage, the output terminals of the first comparator circuit are substantially cut off, so that the third integrating capacitor is charged. When the third integrated voltage obtained across the third integrating capacitor exceeds a predetermined level, a signal is output for determining the position at which the semiconductor switch of the ignition circuit is operated. Here, if t is the time from when the first signal becomes equal to or higher than the threshold level until the signal for determining the position at which the semiconductor switch is operated is output, this time t is constant. If the angle corresponding to this time t is α and the rotation speed is N (rpm), then α=6Nt, and α
becomes larger as the rotational speed N increases. In other words, the ignition position is delayed as the engine speed increases. Therefore, by setting a constant so that the amount of advance angle obtained by the first and second integral circuits is greater than the amount of retardation obtained by the third integral circuit, the advance angle can be improved in the medium and high speed range. , it is possible to obtain the characteristic of retarding the angle in the high-speed region. As mentioned above, if a third integrating capacitor is provided between the output terminals of the comparison circuit that compares the first and second integrated voltages, a circuit to control charging and discharging of this third integrating capacitor becomes unnecessary. , the third integration circuit can be simplified, and advance angle characteristics and retard angle characteristics can be obtained with a simple configuration. [Examples] Examples of the present invention will be described below with reference to the accompanying drawings. [] Configuration of the first embodiment The ignition device of this embodiment consists of an ignition circuit 4 and a control circuit that controls the semiconductor switch (transistor 3) of the ignition circuit 4. The control circuit to control includes a signal coil 5, a rectangular wave generation circuit 6, and a pulse shaping circuit 7.
, a first integrating circuit 8, a second integrating circuit 9,
It consists of a reset circuit 10, a first comparison circuit 11, a third integration circuit 12, and a second comparison circuit 13. Each of these parts will be explained in order below. a Ignition circuit 4 Fig. 1 shows the basic configuration of an embodiment of the present invention. In the figure, 1 is an ignition coil having a primary coil 1a and a secondary coil 1b whose ends are commonly connected; is an ignition plug that is attached to a cylinder of an engine (not shown) and has a non-ground terminal connected to the other end of a secondary coil of an ignition coil via a high voltage cord. A common connection point between the primary coil and one end of the secondary coil of the ignition coil 1 is a transistor 3 as a semiconductor switch for controlling the primary current, whose emitter is grounded.
is connected to the collector of the primary coil, and the other end of the primary coil 1a1
is connected to the positive terminal of a battery (not shown) whose negative terminal is grounded. Note that a Darlington-connected composite transistor is used as the transistor 3 in this example. The ignition coil 1, spark plug 2, and transistor 3 constitute an ignition circuit 4. In the above ignition circuit, the transistor (hereinafter also referred to as a semiconductor switch) 3 is made conductive by a control circuit (described later) by applying a base current from a power source (not shown) through a resistor Rs at a position whose phase is advanced from the ignition position of the engine. , the base current is cut off at the ignition position and the transistor 3 is placed in the cut-off state. When transistor 3 is turned off,
Since the primary current that had been flowing between the primary coil 1a of the ignition coil and the collector-emitter of the transistor 3 is cut off, the primary current flows through the primary coil 1a and the collector-emitter of the transistor 3.
A high voltage is induced in the direction that causes the current to continue flowing. At this point, a large magnetic flux change occurs in the iron core of the ignition coil, and a high voltage is induced in the secondary coil due to this magnetic flux change. Since this high voltage is applied to the spark plug 2, a spark discharge occurs in the spark plug,
The engine is ignited. That is, in the ignition circuit of this example, the position where the semiconductor switch 3 performs the cutoff operation is the ignition position. b Signal Coil 5 The signal coil 5 is disposed within a signal generator that rotates in synchronization with the rotation of the engine, and one end thereof is grounded. As shown in FIG. 2A, the signal coil 5 exceeds the threshold level Vt at the first rotational angular position θ1 of the engine and at the second rotational angular position θ2, which is delayed in phase from the first rotational angular position. A first signal Vs1 and a second signal Vs2 are generated. In this example, the first rotation angle position θ1 corresponds to the maximum advance angle position of the engine, and the second rotation angle position θ2 corresponds to the minimum advance angle position (maximum retard position) of the engine. The horizontal axis of Fig. 2 shows the rotation angle θ of the engine, and the angles at each position, such as the first rotation angle position θ1 and the second rotation angle position θ2, are advanced from the engine top dead center TDC. Measured on the side. In this type of ignition system, when the engine speed is extremely low, the second signal Vs2 is set to be larger than the first signal Vs1, and when the engine is started, the second signal Vs2 is set to be larger than the first signal Vs1. The signal becomes equal to or higher than the threshold level before the first signal. b Rectangular wave generation circuit 6 and pulse shaping circuit 7 The rectangular wave generation circuit 6 takes the output of the signal coil 5 as input and continues from the first rotational angular position to the second rotational angular position as shown in FIG. 2B. The pulse shaping circuit 7 outputs a rectangular wave signal Vq as shown in FIG.
As shown in , the second signal Vs2 is shaped to output a pulse Vp that rises at the second rotation angle position θ2. c First integrating circuit 8 The first integrating circuit 8 is the first integrating capacitor 8a.
It is equipped with an initial charging circuit 8A and an additional charging circuit 8B, and the first integrating capacitor 8a is charged at the first rotation angle position θ1 until the terminal voltage of the first integrating capacitor 8a reaches the set value Vo. 1 charging current
There is an initial integration operation in which initial charging is performed with I11, and after the terminal voltage of the first integration capacitor 8a reaches the set value, the first integration capacitor is charged with a second charging current I12 (<
I11) performs an additional integral operation for additional charging. d Second integrating circuit 9 The second integrating circuit 9 is connected to the second integrating capacitor 9.
a and a charging circuit 9A that charges the capacitor 9a with a constant current 12, and performs an integral operation of charging the second integral capacitor at a constant time constant from each second rotation angle position θ2. e Reset circuit 10 The reset circuit 10 includes a first integrating capacitor 8
A circuit in which the first integrating capacitor 8a and the second integrating capacitor 8b are each discharged between the position where the terminal voltage of a exceeds the terminal voltage of the second integrating capacitor and the second rotation angle position θ2, In this example, the pulse signal that rises at the second rotation angle position θ2
With Vp as input, the first rotation angle position θ2
And the second integrating capacitors 8a and 9a are discharged almost instantaneously. Therefore, the first integral voltage Vc1 obtained across the first integrating capacitor 8a has a waveform as shown by the solid line in FIG. The waveform of voltage Vc2 is as shown by the broken line in FIG. 2D. The terminal voltages of the first and second integrating capacitors are used to generate a signal that determines the position at which the semiconductor switch 3 is operated (in the above example, cut-off operation) in order to perform the ignition operation.
After the signal is generated, it is no longer necessary, so the first
Also, the reset of the second integration circuit does not necessarily have to be performed at the second rotation angle position. Therefore, the reset circuit 10 resets the semiconductor switch 3 between the position where the signal determining the operating position of the semiconductor switch 3 is generated (the position where the third integrated voltage described later becomes equal to or higher than the reference voltage) and the second rotational angular position θ2. Any circuit may be used as long as it discharges the first integrating capacitor 8a and the second integrating capacitor 8b, respectively. f First comparator circuit 11 The first comparator circuit 11 is connected to the first integrating capacitor 8
It consists of a comparator that compares the first integrated voltage Vc1 obtained across the terminals of a and the second integrated voltage Vc2 obtained across the second integrating capacitor 9a. , first integrated voltage
When Vc1 is less than or equal to the second integrated voltage Vc2, it is substantially in a short-circuit state (the switching means constituting the output stage of the comparator is in a conductive state), and the first integrated voltage Vc1 is lower than the second integrated voltage Vc2.
When the integrated voltage Vc2 is exceeded, the circuit becomes substantially cut off. g Third integration circuit 12 The third integration circuit 12 includes a third integration capacitor 12a connected in parallel between the output terminals of the first comparison circuit 11, and a charging circuit 12b that charges this capacitor with a constant current I3. When the output terminals of the first comparison circuit 11 are in a cutoff state, an integration operation is performed to charge the third integration capacitor 12a at a predetermined time constant. The waveform of the third integrated voltage Vc3 obtained across the third integrating capacitor is as shown in FIG. 2E. h Second comparison circuit 13 The second comparison circuit 13 outputs a third integrated voltage Vc3 obtained across the third integrating capacitor 12a,
A reference voltage obtained across a resistor 14b of a voltage divider circuit 14 consisting of a series circuit of resistors 14a and 14b connected between the output terminals of a DC constant voltage source (not shown)
Vr, and when the third integrated voltage Vc3 becomes equal to or higher than the reference voltage Vr, a signal is output for determining the position at which the semiconductor switch 3 is operated. In this embodiment, since the ignition operation is performed when the semiconductor switch 3 of the ignition circuit 4 is cut off,
The second comparator circuit 13 is configured so that when the third integrated voltage Vc3 exceeds the reference voltage Vr, the output voltage V13 becomes zero as shown in FIG. In the case where an ignition circuit is used in which the ignition operation is performed by so that the voltage between them is at a high level). In this embodiment, the second comparison circuit 13 and the reference voltage generation circuit 14 constitute a circuit that outputs an ignition signal when the third integrated voltage exceeds a predetermined level. If the switch has an appropriate trigger level (the level that the control signal must exceed to trigger the semiconductor switch), the third integrated voltage can be directly applied without the need for a second comparator circuit. It is also possible to input it to the control terminal of a semiconductor switch. In that case, the line connecting the third integrating capacitor and the control terminal of the semiconductor switch becomes a circuit for outputting the ignition signal. [] Operation of the embodiment shown in FIG. 1 When the engine speed N (rpm) is low, the time to charge the second integral capacitor 9a is long enough, so the first integral voltage Vc1 is at the second rotation angle position. (Minimum advance angle position) Even if θ2 is reached, the second integral voltage remains
It cannot exceed Vc2. In this state, the first
Since the output terminals of the comparator circuit 13 are short-circuited, the third integrator circuit cannot perform an integrating operation, and the second comparator circuit 13 outputs a signal for determining the position at which the semiconductor switch 3 is operated. I can't. Although not shown in FIG. 1, a switch circuit that is made conductive by a pulse signal Vp that rises at the second rotation angle position θ2 is provided in parallel between the base and emitter of the transistor 3, and the conduction of the switch circuit causes the transistor 3 to become conductive. If you try to block it,
The ignition operation at low speed can be performed at the second rotation angle position θ2. During one rotation of the engine, the second integrating capacitor 9
The time a is charged is the engine rotation speed N (rpm)
As the rotation speed increases, the second integrated voltage Vc2 decreases as the rotational speed increases. Therefore, as the engine speed increases, the first rotational angle position will eventually reach a position that is further advanced than the second rotational angle position θ2.
The integrated voltage Vc1 becomes equal to or higher than the second integrated voltage Vc2. In such a state, the output terminals of the first comparator circuit 11 are cut off, so that the third integrating capacitor 12a is charged. When the third integrated voltage obtained across the capacitor 12a exceeds the reference voltage Vr, the output terminals of the second comparator circuit 13 become short-circuited.
As a result, the base and emitter of the transistor 3 are short-circuited. As a result, the transistor 3 is turned off, and an ignition operation is performed. In the above configuration, the position where the first integrated voltage Vc1 becomes equal to or higher than the second integrated voltage Vc2 advances as the engine speed increases. In contrast, the third integration circuit 8 attempts to retard the ignition position. In other words, if t is the time from when the first signal Vs1 becomes equal to or higher than the threshold level until the second comparison circuit outputs a signal for determining the position at which the semiconductor switch is operated, then this time t is constant. It is. If the angle corresponding to this time t is α and the rotational speed is N (rpm), then α=6Nt, and α increases as the rotational speed N increases. In other words, the ignition position is delayed as the engine speed increases. Therefore, by setting constants so that the amount of advance angle obtained by the first and second integrating circuits is greater than the amount of retarding angle obtained by the third integrating circuit, as shown in FIG. In the medium and high speed range, the angle is advanced,
It is possible to obtain the characteristic of retarding the angle in the high speed region. [] Configuration of the embodiment shown in FIG. 3 Next, a more specific embodiment of the present invention will be described with reference to FIG. In this embodiment, a fourth integration circuit 15 and a comparison circuit 16 are added to control the angle at which the transistor 3 of the ignition circuit 4 conducts (the conduction angle of the primary current of the ignition coil). The configuration of each part of this embodiment is as follows. a Pulse shaping circuit 7 The pulse shaping circuit 7 has a cathode connected to the signal coil 5.
a diode 7a connected to the non-grounded terminal of
A capacitor 7b and a resistor 7, one end of which is connected to the anode of the diode 7a, and the other end of which is commonly connected.
c, an NPN transistor 7d serving as a waveform shaping switch whose base is connected to the common connection point of the capacitor 7b and the other end of the resistor 7c and whose emitter is grounded, and an anode directed toward the ground between the base of the transistor 7d and the ground. diode 7 connected
e, and resistors 7f and 7g, one end of which is connected to the base and collector of a transistor 7d, respectively. In this pulse shaping circuit 7, when the second signal Vs2 generated by the signal coil 5 exceeds the threshold level at the second rotation angle position, the voltage drop generated across the diode 7e causes the transistor 7d to become extremely short. A time-blocking state is entered, and a pulse signal Vp is output between the collector and emitter of the transistor 7d at the second rotation angle position θ2. b Rectangular wave generation circuit 6 The rectangular wave generation circuit 6 has an anode connected to the signal coil 5.
a diode 6a connected to the non-grounded terminal of the
A capacitor 6b and a resistor 6c, one end of which is connected to the cathode of the diode 6a, and the other end of which is commonly connected.
, an NPN transistor 6e whose base is connected to the common connection point of the capacitor 6b and the resistor 6c via a resistor 6d, and whose emitter is grounded, and a PNP transistor 6h whose base is connected to the collector of the transistor 6e via a resistor 6g. , a resistor 6i connected between the base and emitter of the transistor 6h
, a signal storage capacitor 6j connected between the collector of the transistor 6h and ground, an NPN transistor 6k whose emitter is grounded and whose collector is connected to the collector of the transistor 6h, and one end connected to the base of the transistor 6k. resistance 6
The emitter of the transistor 6h is connected to the output terminal of a DC constant voltage power supply (not shown), and the base of the transistor 6k is connected to the collector of the transistor 7d (output terminal of the pulse shaping circuit 7) of the pulse shaping circuit 7 through a resistor 6m. It is connected. In this rectangular wave signal generation circuit 6, when the signal coil 5 generates the first signal Vs1 at the first rotation angle position, the period during which the first signal Vs1 is equal to or higher than a predetermined threshold level Vt. Transistor 6e is triggered, transistor 6h becomes conductive, and signal storage capacitor 6j is instantly charged to the power supply voltage E1 with the illustrated polarity through the collector-emitter of transistor 6h. When the pulse signal Vp is obtained at the collector of the transistor 7d of the pulse shaping circuit 7, the transistor 6k becomes conductive, so that the capacitor 6j is instantaneously discharged between the collector and emitter of the transistor 6k. Therefore, a rectangular wave signal voltage Vq having a peak value of E that lasts from the first rotational angular position θ1 to the second rotational angular position θ2 is obtained at both ends of the signal storage capacitor 6j. c First integrating circuit 8 Next, the first integrating circuit 8 includes a first integrating capacitor 8a, a voltage dividing circuit consisting of a series circuit of resistors 8b and 8c, a transistor 8d, a speed-up capacitor 8e, and a resistor. 8f and 8g, and a voltage dividing circuit consisting of resistors 8b and 8c is connected in parallel to both ends of the signal storage capacitor 6j.
The base of the transistor 8d is connected to the voltage dividing point of the voltage dividing circuit, and the collector is connected to the non-ground terminal of the signal storage capacitor 6j via the resistor 8g. A speed-up capacitor 8e is connected between the base and collector of a transistor 8d, and a resistor 8f is connected between the collector and emitter of the transistor 8d. The first integrating capacitor 8a is connected between the emitter of the transistor 8d and ground, and the first integrating capacitor 8a is connected between the collector and emitter of the transistor 8d and through the resistor 8f by the rectangular wave signal voltage Vq obtained across the signal storage capacitor 6j. The capacitor 8a is now charged. That is, when a rectangular wave signal voltage Vq is generated across the signal storage capacitor 6j, a base current flows through the transistor 8d, making the transistor 8d conductive, and the first integral is generated through the collector-emitter of the transistor 8d and the resistor 8f. Capacitor 8a
is charged with the first charging current I11 to the polarity shown, and an initial integration operation is performed. The terminal voltage of the first integrating capacitor 8a is the voltage Vq across the capacitor 6j.
When the set voltage (voltage across the resistor 8c) obtained by dividing the voltage by the resistors 8b and 8c is reached, the base current stops flowing to the transistor 8d and the transistor 8d is cut off. From then on, the terminal voltage of the capacitor 6j capacitor 8 through resistor 8f.
a is additionally charged with the second charging current I12 (<I11) and an additional integration operation is performed. The waveform of the first integrated voltage Vc1 obtained across the first integrating capacitor 8a is as shown by the solid line in FIG. 2D. In this embodiment, the signal storage capacitor 6j
The magnitude of the set voltage Vo obtained by dividing the voltage Vq obtained across the voltage Vq by the resistors 8b and 8c is the voltage Vq
Let E be the peak value of , and let R1 and R2 be the resistance values of resistors 8b and 8c, respectively, and it is given by the following formula. Vo=(ER2)/(R1+R2)...(12) d Second integrating circuit 9 The second integrating circuit 9 includes a second integrating capacitor 9a whose one end is grounded, and a non-grounded terminal of the capacitor 9a. and a resistor 9b connected between the output terminal of the DC constant voltage power supply and the output terminal of the DC constant voltage power supply. The capacitor 9a of this second integrating circuit 9 is charged at a constant time constant through a resistor 9b by the output of a DC constant voltage power supply (not shown), and the capacitor 9a
A second integrated voltage Vc2 as shown by the broken line in FIG. 2D is obtained at both ends of . e Reset circuit 10 The reset circuit 10 includes a first integrating circuit reset circuit 10A and a second integrating circuit reset circuit 1.
It consists of 0B. The first integrating circuit reset circuit 10A includes a reset transistor (NPN transistor) 10a whose emitter is grounded and whose collector is connected to the non-grounded terminal of the first integrating capacitor 8a, and one end connected to the base of the transistor 10a. and a resistor 10b whose other end is connected to the collector of the transistor 7d. When the pulse signal Vp is generated at the second rotation angle position θ2, the transistor 10a becomes conductive and instantly discharges the first integrating capacitor 8a. let Therefore, the first integrated voltage obtained across the first integrating capacitor 8a
Vc1 becomes zero at the second rotation angle position θ2 as shown in FIG. 2D. Further, the second integrating circuit reset circuit 10B is
A discharge transistor (NPN transistor) 10c whose collector is connected to the non-grounded terminal of the capacitor 9a and whose emitter is grounded, and a transistor 1
It consists of a resistor 10d connected between the base of the transistor 0c and the collector of the transistor 7d, and when the pulse signal Vp is generated at the second rotation angle position θ2, the transistor 10c becomes conductive and momentarily connects the second integrating capacitor 9a. is discharged. Therefore, as shown in FIG. 2D, the second integrated voltage Vc2 becomes zero at the second rotational angular position θ2. f First comparison circuit 11 The first comparison circuit 11 consists of a voltage comparator made of an IC, and the positive phase input terminal of this comparator has a first
The first integrated voltage Vc1 obtained across the integrating capacitor 8a is applied to the negative phase input terminal, and the second integrated voltage Vc1 obtained across the second integrating capacitor 9a is applied to the negative phase input terminal.
Vc2 is input respectively. g Third Integrating Circuit 12 The third integrating circuit 12 consists of a third integrating capacitor 12a and a resistor 12b connected between the output terminals of the comparator circuit 11. 12a is charged with a constant current. h Second comparison circuit 13 The configuration of the second comparison circuit 13 is the same as that shown in FIG.
Vc3 and a reference voltage Vr obtained from the reference voltage generation circuit 14 are input. i Fourth integrator circuit 15 The fourth integrator circuit 15 is a fourth integrator circuit 15 whose one end is grounded.
an integrating capacitor 15a, a discharge transistor (NPN transistor) 15b whose collector is connected to the non-grounded terminal of the capacitor 15a and whose emitter is grounded, a resistor 15c whose one end is connected to the base of the transistor 15b, and a transistor 15b.
A resistor 15d connected between the base and emitter of b
, the other end of the resistor 15c and the signal storage capacitor 6
A capacitor 15e connected between the non-ground terminal of the fourth integrating capacitor 15a, a resistor 15h whose one end is connected to the non-ground terminal of the fourth integrating capacitor 15a, and a resistor 1
The fourth integrating capacitor 15a has a diode 15i whose cathode is connected to the other end of the signal storage capacitor 6j and whose anode is connected to the non-grounded terminal of the signal storage capacitor 6j. 15i and resistance 15h
It is charged at a constant time constant through In this embodiment, a differential circuit 15g is configured by resistors 15c and 15d and a capacitor 15e. This differentiating circuit 15g differentiates the rising edge of the rectangular wave signal Vq obtained across the signal storage capacitor 6j, outputs a pulse current If, and conducts the transistor 15b while the pulse current is being generated. The integrating capacitor 15a is discharged. j Comparison circuit 16 The comparison circuit 16 consists of a voltage comparator made of an IC, and a resistor Rs is connected between the output terminal of this comparator and the power supply terminal. The output terminal of this comparison circuit 16 is connected to the base (control signal input terminal) of the transistor 3 of the ignition circuit. The fourth integrated voltage Vc4 obtained across the fourth integrating capacitor 15a is input to the negative phase input terminal of the comparison circuit 16, and the fourth integrated voltage Vc4 obtained across the second integrating capacitor 9a is input to the positive phase input terminal of the comparing circuit 16. The obtained second integrated voltage Vc2 is input. k Spontaneous ignition prevention resistor 17 In this embodiment, a spontaneous ignition prevention resistor 17 is provided between the connection point between the resistor 15h of the fourth integrating circuit 15 and the diode 15i and the collector of the transistor 7d of the pulse shaping circuit 7. connected, and when the transistor 7d is conductive, the circuit from the fourth integrating capacitor 15a to the transistor 7d via the resistors 15h and 17 causes the capacitor 15a to
A discharge circuit is now configured. The resistance value of the resistor 17 is set to a sufficiently large value so that normal charging of the fourth integrating capacitor 15a is not hindered during steady operation. [] Operation a of the embodiment shown in FIG. 3 Operation when normal starting operation is performed In normal operation of the engine, the engine starting operation is performed immediately after closing a power switch (not shown). When the engine is started, the signal coil 5 outputs first and second signals Vs1 and Vs2. When the engine is running at an extremely low speed, the first signal Vs1 does not exceed the threshold level, and only the second signal Vs2 exceeds the threshold level. Therefore, when the engine speed is extremely low, a signal large enough to trigger the transistor 6e of the rectangular wave generating circuit 6 cannot be obtained. In the pulse shaping circuit 7, a base current flows from a power supply (not shown) to the transistor 7d through the resistor 7f, so that the transistor 7d is conductive. When the second signal Vs2 is generated, a current flows through the diode 7e, resistor 7c, capacitor 7b, and diode 7a of the pulse shaping circuit 7, and the second signal Vs2 is generated.
When the voltage across the diode 7e reaches a predetermined value at the rotation angle position θ2 (when the second signal Vs2 becomes equal to or higher than the threshold level Vt), the transistor 7
The base and emitter of transistor 7d is reverse biased, and transistor 7d is cut off. Second signal Vs2
When the voltage falls below the threshold level, transistor 7d becomes conductive again. Therefore, a second signal Vs2 is applied between the collector and emitter of the transistor 7d.
A pulse signal Vp is obtained with a pulse width corresponding to the period during which V is equal to or higher than the threshold level. In this way, when the engine is running at extremely low speed, the pulse signal
Since only Vp is generated and the transistor 6e of the square wave generation circuit 6 is not triggered, the transistor 6
h is not conductive and capacitor 6j is not charged.
Therefore, the first integrating capacitor 8a and the fourth integrating capacitor 15a are not charged. In the second integrating circuit, the second integrating capacitor 9a is charged from the power supply through the resistor 9b to the polarity shown in the figure, and when the transistor 9b is turned on by the pulse signal Vp, the capacitor 9a is discharged. At both ends, as shown in FIG. 2D, a second integrated voltage Vc2 is obtained which increases at a constant gradient from each second rotational angular position θ2 and returns to zero at the next second rotational angular position θ2. As described above, the fourth integrating capacitor 15a is not charged by the rectangular wave signal Vq at extremely low speed, but the transistor 7d of the pulse shaping circuit 7 during the period when the second signal Vs2 is above the threshold level. When the capacitor is cut off, a charging current flows from a power source (not shown) to the fourth integrating capacitor 15a through the resistor 7g and the resistors 17 and 15h. Therefore, the fourth integrating capacitor is slightly charged while the second signal Vs2 is above the threshold level, and its terminal voltage Vc4 increases slightly. The comparator circuit 16 converts this voltage Vc4 into a second integrated voltage.
Compare with Vc2. When voltage Vc2 becomes larger than voltage Vc4, output voltage Vd of comparator circuit 16 becomes high level. Furthermore, since the first integral voltage Vc1 is not generated, the output terminals of the comparator circuit 11 remain short-circuited, and the third integral capacitor 12a is not charged. Therefore, the output terminals of the comparator circuit 13 are in a disconnected state. Therefore, when the output voltage Vd of the comparison circuit 16 becomes high level, the base-emitter voltage V13 of the transistor 3 becomes high level. As a result, a base current flows through the transistor 3, making the transistor 3 conductive, and the primary current flows through the ignition coil 1.
I1 flows. Next, when the second integrated voltage Vc2 becomes zero at the second rotation angle position, the potential of the output terminal of the comparator circuit 16 becomes the ground level, so the transistor 3 is cut off and the primary current I1 is suddenly cut off. . This causes a large magnetic flux change in the iron core of the ignition coil, and a spark is generated in the ignition plug 2. In this way, in this embodiment, the ignition operation is performed at the minimum advance angle position θ2 even at extremely low engine speeds when the first signal Vs1 does not exceed the threshold level, so that the engine startability is improved. I can do it. When the rotational speed increases to a certain extent by starting the engine, the first voltage Vs1 also becomes equal to or higher than the threshold level. At this time, the rectangular wave generating circuit 6 generates a rectangular wave voltage Vq that lasts from the first rotational angular position θ1 to the second rotational angular position θ2, as shown in FIG. 2B. When the rectangular wave signal Vq is generated, the first integrating circuit 8 performs the initial integrating operation and the additional integrating operation as described above. An integrated voltage Vc1 of 1 is obtained. In the second integration circuit 9, the second integration voltage Vc2 as shown in FIG. 2D is obtained across the second integration capacitor 9a by the operation already described. In the fourth integrating circuit 15, the output pulse current of a differentiating circuit 15g that differentiates the rise of the rectangular wave signal Vq is
The fourth integrating capacitor 15a is charged with a constant time constant by the signal rectangular wave signal voltage Vq from the position where the transistor 15b is cut off when the signal If disappears to the second rotational angle position θ2, and the rectangular wave signal voltage Vq disappears. Thereafter, the terminal voltage of the fourth integrating capacitor is maintained until the next first rotational angular position θ1. When the rectangular wave signal Vq rises at the first rotation angle position θ1 and the differentiating circuit 15g outputs a pulse current If, the transistor 15b becomes conductive and discharges the capacitor 15a. Therefore, both ends of the fourth integral capacitor 15a rise at a constant gradient from a position delayed by a predetermined angle from each first rotational angle position θ1 to a second rotational angle position θ2 to reach the next maximum advanced angle position. A fourth integrated voltage Vc4 is obtained that maintains that voltage until θ1. The second integrated voltage Vc2 and the fourth integrated voltage Vc4
is input to the comparison circuit 16. In the comparator circuit 16, the fourth integrated voltage Vc4 is equal to the second integrated voltage Vc4.
When the voltage is higher than Vc2, the output stage of the comparator circuit 16 is in a conductive state, and the ground voltage Vd at its output terminal is at zero level. The second integrated voltage Vc2 is the fourth
When the integrated voltage Vc4 is exceeded, the output stage of the comparator circuit 16 is cut off and the voltage Vd at its output terminal becomes high level. During the period when the output voltage Vd of the comparator circuit 16 is zero, the potential of the base of the transistor 3 is kept at the ground level and conduction of the transistor 3 is prohibited, and conduction of the transistor 3 is allowed only during the period when the voltage Vd is at a high level. be done. The first integrated voltage Vc1 and the second integrated voltage Vc2 are input to the comparison circuit 11. First integrated voltage Vc1
is less than the second integrated voltage Vc2, the comparator circuit 1
One output stage is in a conducting state, and when the first integrated voltage Vc1 exceeds the second integrated voltage Vc2, the output stage of the comparator 11a becomes in a cut-off state. When the first integral voltage Vc1 is less than the second integral voltage Vc2, the output terminals of the comparator circuit 11 are in a short-circuited state, so that the third integral capacitor 12a is not charged.
At this time, the output terminals of the second comparison circuit 13 are in a disconnected state. Therefore, the comparator circuit 13 allows the base current to flow through the transistor 3, which serves as a semiconductor switch for controlling the primary current, thereby making the transistor 3 conductive, and causing the primary current I1 to flow through the ignition coil. When the first integral voltage Vc1 exceeds the second integral voltage Vc2 at the angle θi, the output terminals of the comparator circuit 11 are cut off, and charging of the third integral capacitor 12a is started. Third integrating capacitor 12a
The third integrated voltage Vc3 obtained at both ends of is the reference voltage
When the voltage exceeds Vr, the output terminals of the second comparison circuit 13 become short-circuited. As a result, the transistor 3 is turned off and the primary current I1 of the ignition coil is suddenly changed, so that a high voltage Vh is induced in the secondary coil 1b of the ignition coil. This causes a spark discharge to occur in the spark plug 2 attached to the cylinder of the engine, and the engine is ignited. This embodiment is similar to the embodiment shown in FIG. 1 in that a retarded angle characteristic is obtained by providing the third integrating circuit. As mentioned above, when the transistor 3 (primary current control switch) is made conductive when the second integrated voltage Vc2 exceeds the fourth integrated voltage Vc4, the constants of the differentiating circuit 15g (resistors 15c, 15d
and the time constant determined by the capacitor 15e) and the integration constant of the fourth integrating circuit 15 (the time constant determined by the capacitor 15a)
By appropriately setting the time constant determined by the resistor 15h and the time constant determined by the resistor 15h, it is possible to arbitrarily set the position at which the primary current control switch starts conducting. Therefore, by setting the integration constant of the fourth integration circuit so that the period during which the primary current of the ignition coil is energized is the minimum necessary when the engine is running at low speed, the loss can be minimized. It is possible to suppress the temperature rise of the switch elements constituting the next current control switch. Furthermore, the position θ3 at which charging of the fourth integral capacitor starts is delayed as the engine rotational speed increases, and the position where the second integral voltage exceeds the fourth integral voltage is determined by the engine rotational speed. Since it progresses as the engine speed increases, the primary current energization time becomes longer as the rotational speed of the engine increases.
Therefore, it is possible to prevent the breaking current value from becoming low when the engine is running at high speed, and it is possible to prevent the ignition performance from decreasing when the engine is running at high speed. b Operation when engine starting operation is abnormal (effect of spontaneous combustion prevention resistor 17) In the above example, when the power switch is held in the closed state while the engine is stopped, that is, when the power switch is closed, Consider the case where the starting operation is not performed immediately after the start. When the engine is stopped, the signal coil 5 does not output the first and second signals Vs1 and Vs2, so the rectangular wave signal Vq and pulse signal Vp are not generated. Therefore, the first and fourth integrating capacitors 8a and 15a are not charged by the rectangular wave signal Vq. However, since the second integrating capacitor 9a is charged from a power supply (not shown) through the resistor 9b, its terminal voltage Vc2 increases at a predetermined slope and eventually becomes saturated. This terminal voltage of the second integrating capacitor short-circuits the output terminals of the comparator circuit 11, thereby preventing charging of the third integrating capacitor 12a. At this time, the output terminals of the second comparison circuit 13 are in a cutoff state, the base current is supplied to the transistor 3, the transistor 3 is turned on, and the primary current flows through the ignition coil 1. At this time, in the comparator circuit 16, a weak current flows from the power supply through the inside of the comparator from the negative phase input terminal and the positive phase input terminal of the comparator. Now, in FIG. 3, if there is no spontaneous combustion prevention resistor 17, a weak current flowing from the negative phase input terminal of the comparator circuit 16 causes the fourth integrating capacitor 15 to
a is charged, the fourth integrating capacitor 15
The terminal voltage Vc4 of the fourth integrating capacitor 15a increases, and eventually the terminal voltage Vc4 of the fourth integrating capacitor 15a increases to the second
The integrated voltage Vc2 will be exceeded. In this manner, when the fourth integrated voltage Vc4 exceeds the second integrated voltage Vc2, the output terminal of the comparator circuit 16 becomes the ground potential, so the transistor 3 is cut off and the primary current I1 is cut off. Therefore, a large magnetic flux change occurs in the iron core of the ignition coil 1, and a high voltage is induced in the secondary coil of the ignition coil. Since this high voltage is applied to the ignition plug 2, a spark is generated in the ignition plug, resulting in so-called spontaneous ignition. On the other hand, if the spontaneous ignition prevention resistor 17 is provided as in the above embodiment, when the power switch is held in the closed state while the engine is stopped, the spontaneous ignition prevention resistor 15h The fourth integrating capacitor 15a is discharged through the conductive resistor 17 and the transistor d of the pulse shaping circuit 7, which prevents the terminal voltage of the fourth integrating capacitor from increasing and prevents spontaneous combustion from occurring. Prevented. [] Embodiment of FIG. 4 FIG. 4 shows the main part of another embodiment of the present invention. This embodiment uses a capacitor discharge type circuit as the ignition circuit, and the first comparison circuit 11 A programmable union transistor (PUT) P1 is used as a comparator. In this embodiment, a capacitor C1 is provided on the primary side of the ignition coil 1, and the capacitor C1 is charged to the polarity shown in the figure through a diode D1 by the output of an exciter coil Le provided in a magnetic alternator that rotates synchronously with the engine. It is becoming more and more common. A thyristor Th is provided between the connection point of the capacitor C1 and the diode D1 and ground, and a protective resistor R1 is connected between the gate and cathode of the thyristor Th.
Further, a diode D2 with a cathode facing the ground side is connected to both ends of the primary coil 1a of the ignition coil 1. Ignition coil 1, spark plug 2, capacitor C1, exciter coil Le, diode D1,
Ignition circuit 4 by D2, thyristor Th and resistor R1
is configured. This ignition circuit 4 is well known as a capacitor discharge type circuit, and the electric charge of the capacitor C1 is transferred to the primary coil 1 of the ignition coil 1 by conduction of the thyristor Th.
When the secondary coil 1b is discharged, a high voltage is induced in the secondary coil 1b to perform an ignition operation. Also, in this embodiment, the first integrating capacitor 8a
A first integrated voltage Vc1 across the programmable unidirectional transistor P1 is applied to the anode of the programmable unidirectional transistor P1, and a second integrated voltage Vc2 across the second integrating capacitor 9a is applied to the programmable unidirectional transistor P1 through the resistor 20. applied to the gate. The cathode of the programmable union transistor P1 is connected to one end of the third integrating capacitor 12a via a resistor 12b, and the other end of the third integrating capacitor 12a is grounded. The non-grounded terminal of the third integrating capacitor 12a is connected to the gate of the thyristor Th of the ignition circuit.
When the terminal voltage of the integrating capacitor 12a exceeds a predetermined trigger level, an ignition signal is supplied to the thyristor Th. When the first integral voltage Vc1 is lower than the second integral voltage Vc2, the programmable union transistor P1 is cut off and no charging current is supplied to the third integral capacitor 12a. When the integrated voltage of Vc2 or more becomes
Since P1 is conductive, the third integrating capacitor 12
A charging current is supplied to a. When the voltage across the third integrating capacitor exceeds a predetermined level, an ignition signal is applied to the thyristor Th, which makes the thyristor Th conductive and performs the ignition operation. In addition, in the embodiment shown in Fig. 4, the thyristor
A pulse signal Vp is supplied to the gate of Th through a resistor 21, and when the engine is running at low speed, this pulse signal provides an ignition signal to the thyristor Th. In FIG. 4, the first integrating capacitor 8
Although the illustration of the reset circuit for discharging a is omitted, a circuit similar to that used in the embodiment of FIG. 3 can be used as the reset circuit for this first integrating capacitor. The signal waveforms of each part of the embodiment of FIG. 4 are shown in FIGS. 5 to E. In FIG. 5D, the broken line Vc1 indicates the first integrated voltage before the start of the advance angle operation, and the solid line
Vc1 indicates the first integrated voltage after the end of the advance angle. In the above embodiment, the rectangular wave signal Vq and the pulse signal Vp are generated by the output of the signal coil, and these signals are used to control the first integrating circuit and the second integrating circuit. The method of controlling the circuit is not limited to the above embodiment.
In the first integration circuit, the start position of the initial integration operation may be determined by the first signal, and the end position of the additional integration operation may be determined by the signal indicating the ignition position or the second signal. Further, the second integrating circuit may have a starting position of its integrating operation determined by the second signal, and a finishing position of its integrating operation may be determined by the signal indicating the ignition position or the second signal. [Effect of the invention] As described above, according to the present invention, the first and second
the first obtained at both ends of the integrating capacitor of
and the second integrated voltage, and when the first integrated voltage is less than or equal to the second integrated voltage, there is a substantially short circuit between the output terminals, and the first integrated voltage exceeds the second integrated voltage. A comparator circuit is provided in which the output terminals are substantially cut off at certain times, and an integrating capacitor of a third integrating circuit is connected between the output terminals of the comparator circuit.
Since a signal for determining the ignition position is generated when the terminal voltage of the integrating capacitor of the third integrating circuit reaches a predetermined level, a circuit for controlling charging and discharging of the capacitor of the third integrating circuit is provided. By omitting this, the third integration circuit can be simplified, and there is an advantage that advance angle characteristics and retard angle characteristics can be obtained with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention;
FIG. 2 is a signal waveform diagram of each part of FIG. 1, FIG. 3 is a circuit diagram showing a more specific embodiment of the present invention, and FIG. 4 is a circuit showing the main parts of still another embodiment of the present invention. figure,
FIG. 5 is a signal waveform diagram of each part in FIG. 4, and FIG. 6 is a diagram showing an example of the ignition characteristic obtained by the apparatus of the present invention. DESCRIPTION OF SYMBOLS 1... Ignition coil, 2... Spark plug, 4... Ignition circuit, 5... Signal coil, 6... Square wave generation circuit, 7...
Pulse shaping circuit, 8...first integration circuit, 9...second
10...Reset circuit, 11...Comparison circuit, 12...Third integrating circuit.

Claims (1)

[Claims] 1. One of the ignition coils due to the operation of the semiconductor switch.
an ignition circuit that suddenly changes a secondary current to generate a high voltage for ignition on the secondary side of the ignition coil; a first signal that becomes equal to or higher than a threshold level at a first rotation angle position of the internal combustion engine; a signal coil that generates a second signal that is equal to or higher than a threshold level at a second rotational angular position whose phase is delayed from the first rotational angular position; An ignition device for an internal combustion engine comprising an ignition position control circuit that provides an ignition signal for operating a semiconductor switch between a rotational angular position and a second rotational angular position, the ignition position control circuit comprising: a first ignition position control circuit; an initial integration operation of initially charging the integrating capacitor from the first rotational angular position until the terminal voltage of the first integrating capacitor reaches a set voltage; and an additional integration operation of additionally charging the first integrating capacitor to a voltage higher than the set voltage. a first integrating circuit that performs an integral operation;
The first integrated voltage obtained across the first integrating capacitor and the second integrated voltage obtained across the second integrating capacitor are compared to determine whether the first integrated voltage is higher than the second integrated voltage. A comparator circuit in which the output terminals are substantially short-circuited when the integrated voltage is lower than the integrated voltage, and the output terminals are substantially cut off when the first integrated voltage exceeds the second integrated voltage; a third integrating circuit that performs an integrating operation to charge a third integrating capacitor connected in parallel between the output terminals of the third integrating capacitor with a constant time constant; a circuit that outputs the ignition signal when the integrated voltage exceeds the predetermined level; and a circuit that outputs the ignition signal when the integrated voltage exceeds the predetermined level; An ignition device for an internal combustion engine, comprising a reset circuit that discharges the first and second integrating capacitors, respectively.