JPS6160986B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine ignition timing control device that controls ignition timing according to various parameters of the engine, such as engine speed.

Traditionally, this type of device is synchronized to the engine speed;
It detects the trigger level of the signal voltage of the signal generator that is generated in response to the ignition timing, opens and closes the semiconductor switching element of the ignition device, and generates the ignition voltage on the secondary side of the ignition coil. The engine's ignition timing was determined by the waveform. Therefore, since the ignition timing is determined by the signal voltage waveform, it has not been possible to sufficiently correspond to the ignition timing required by the engine.

The present invention aims to solve such problems, and the first object is to obtain an ignition timing characteristic that retards the ignition timing with a predetermined slope from a constant maximum advance angle, and The objective is to obtain an ignition timing characteristic that changes from a constant advance angle to a constant maximum advance angle, and retards with a predetermined slope from this maximum advance angle.

The present invention will be explained below with reference to the embodiment shown in FIG.

In the figure, denotes an ignition device, and this embodiment uses a well-known CD ignition device as an example, and is configured as follows. That is, reference numeral 1 denotes a generator coil of a magnet electric machine (not shown), which generates positive and negative alternating current voltages in synchronization with the rotation of the engine. 2 and 3 are diodes that rectify the output of the generator coil 1, 4 is a capacitor charged by the rectified output of the diode 2, and 5 is an ignition coil connected to the discharge circuit of the capacitor 4, which is connected in series with the capacitor 4. The primary coil 5a is
It consists of a secondary coil 5b connected to a spark plug 6. A thyristor 7 is a semiconductor switching element connected to the discharge circuit of the capacitor 4. When the thyristor 7 is conductive, the charge in the capacitor 4 is discharged to the primary coil 5a. is an ignition timing control circuit which is a feature of the present invention, and is configured as follows. That is, 8 is a signal coil which is an angular position detecting device, and is attached to the above-mentioned magnet generator together with the generating coil 1. This signal coil 8 generates positive and negative angle signals in synchronization with the rotation of the engine. 1 Angle signal a is the predetermined crank position of the engine, that is, the maximum advance angle position T ₂ required by the engine.
The second angle signal b corresponds to a crank position delayed by a predetermined angle from the generation position of the first angle signal a, that is, the maximum delayed angle position _T1 required by the engine.
9 and 13 are positive and negative angle signals a and b of the signal coil 8.
This is a diode that full-wave rectifies the angle signal and separates it into the first and second angle signals a and b. is a type of flip-flop circuit (hereinafter referred to as the 1st F.F circuit) composed of a thyristor 10, a resistor 11, and a transistor 12. The gate of the thyristor 10 is connected to the A terminal of the signal coil 8, and the base of the transistor 12 is connected to the B end of the signal coil 8. 14 is a flip-flop circuit (hereinafter referred to as the second F.F circuit), 15 is a register, 16 is a capacitor, 17
is an operational amplifier (hereinafter referred to as an operational amplifier), and a register 15 and a capacitor 16 constitute an integrator. 18 and 19 are voltage comparators (hereinafter referred to as comparators), and 20 and 21 are NOR gates. The set terminal S of the second F.F circuit 14 is connected to the B terminal of the signal coil 8, and the output terminal Q is connected to the register 15.
through the inverting input terminal of the operational amplifier 17 (hereinafter referred to as
(referred to as the -) end). The output terminal of the operational amplifier 17 is connected to the (-) terminal of the comparator 18 and also to the (-) terminal via the capacitor 16. Further, the non-inverting input terminal (hereinafter referred to as the (+) terminal) of the operational amplifier 17 is biased to the comparison voltage _V1 , and the (+) terminal of the comparator 18 is grounded. Also, the output terminal of the comparator 18 is
Connected to the reset terminal R of the 2F.F circuit 14. The (+) end of the comparator 19 is connected to the output end of the operational amplifier 17, and the (-) end is biased to the reference voltage _V2 . The output terminal of the comparator 19 and the B terminal of the signal coil 8 are grounded to each input terminal of the NOR gate 20. The output terminal of this NOR gate 20, thyristor 10, resistor 11 and transistor 1
The output terminal of the 1st F.F circuit composed of 2 is NOR.
It is connected to each input terminal of the gate 21, its output terminal is connected to the base of a transistor 22, the collector of this transistor 22 is connected to the power supply terminal Vcc via a resistor 23, and its emitter is connected to the gate of the thyristor 7 of the ignition device. It is connected to the.

The operation of the embodiment configured as above will be explained in detail using the operation explanatory diagram shown in FIG. 2. K shown in FIG. 2 is the crank position of the engine, TDC is the top dead center of the engine, and T ₁ is the maximum retard angle position of the engine where the second angle signal b is generated, and _T2 is the maximum advance angle position of the engine where the first angle signal a is generated. A to I are the first
These are the voltage waveforms and pulse waveforms of each part shown in the figure.

The engine shall require the ignition timing characteristics shown in Figure 3.

First, the operation when the engine is rotating at a constant speed at a rotation speed higher than N ₂ and lower than N ₃ shown in FIG. 3 is as follows. Signal coil 8
First and second angle signals a and b, which have a narrow angular width and change sharply, are generated once per revolution of the engine corresponding to the crank positions T ₁ and T ₂ . When the second angle signal b is input to the set terminal S of the second F.F circuit 14, its output terminal Q becomes high level, so the electric charge of the capacitor 16, which was previously charged to the polarity shown, is expressed by the following formula. It is discharged at a current of I ₂ shown in FIG.

I ₂ = 2nd F. High level voltage of the F.F circuit 14 - comparison voltage V ₁ /resistance value of the register 15 As shown in the above formula, this discharge current I ₂ is the high level voltage of the second F.F circuit 14, the resistance value of the register 15, and the comparison voltage V If ₁ is constant, it will be a constant value even if the engine speed changes. When the capacitor 16 is discharged with the discharge current _I2 , the output voltage D of the operational amplifier 17
As shown in FIG.
8, a positive pulse voltage is generated at the output of the comparator 18, and the second F.
In the F circuit 14, this positive pulse voltage is applied to the reset terminal R.
The signal is input to the output terminal Q and is inverted, so that its output terminal Q becomes a low level.

Due to the low level of the output terminal Q of the second F.F circuit 14, the capacitor 16 is charged again to the illustrated polarity with a current of ₁ shown in the following equation.

₁ = Comparison voltage V ₁ /Resistance value of resistor ₁₅ As shown in the above equation, if the resistance value of resistor 15 and the comparison voltage V ₁ are constant, even if the engine speed changes It becomes a constant value. Therefore, the charging voltage of the capacitor 16, that is, the output voltage D of the operational amplifier 17, is as shown in FIG. 2D.
Regardless of the rotation speed, it will rise linearly with a constant slope. In this way, op amp 1
The output voltage D of 7 is at the generation position T ₁ of the second angle signal b.
When the output voltage D reaches a predetermined voltage at the (+) end of the comparator 18, it becomes a triangular wave output voltage that rises again. This output voltage D is input to the (+) terminal of the comparator 19, and
The comparator ₁₉ generates a high-level output signal E during a period when the output voltage D of the operational amplifier 17 is higher than the reference voltage _V2 . The output signal E of the comparator 19 is input to the first gate of the NOR gate 20, and the second angle signal b of the signal coil 8 is input to the second gate, so the output of the NOR gate 20 is as shown in FIG. As shown, regardless of the second angle signal b of the signal coil 8, the high level output signal E of the comparator 19 remains at a low level during the generation period. On the other hand, the operation of the first F.F circuit composed of the thyristor 10, the register 11, and the transistor 12 is as follows. The first angle signal a of the signal coil 8 is input to the gate of the thyristor 10, and the thyristor 10 becomes conductive, so that the anode end of the thyristor 10 is inverted from a high level based on the power supply voltage Vcc to a low level.

Further, the second angle signal b of the signal coil 8 is input to the base of the transistor 12, and the second angle signal b
The transistor 12 is in a conductive state during the period when
Since the anode current of the thyristor 10 is bypassed by the transistor 12, the thyristor 10 loses its self-holding effect and is reversed to a non-conducting state. This is due to the difference in operating characteristics between the thyristor 10 and the transistor 12. Since the transistor 12 becomes non-conductive when the second angle signal b becomes approximately zero, the connection point between the collector of the transistor 12 and the anode of the thyristor 10, that is, the output signal G of the first F.F circuit changes from a low level to a high level. to be reversed. To explain this operation in detail with reference to FIG. 2, the first angle signal a
At the generation position _T2 , the output signal G of the first F.F circuit is inverted from high level to low level, and at the time when the second angle signal b reaches approximately zero at the generation position _T1 of the second angle signal b. Inverts from low level to high level again. The output signal F of the NOR gate 20 mentioned above is input to the first gate of the NOR gate 21, and when the output signal G of the first F.F circuit is input to the second gate, the output signal H of the NOR gate 21 is input.
As shown in FIG. 2H, when the output signal F of the NOR gate 20 falls from high level to low level, it is inverted from low level to high level, and the 1st F.
When the output signal G of the F circuit rises from low level to high level, it is inverted from high level to low level. When the output signal H of the NOR gate 21 is inverted from low level to high level, the transistor 22 becomes conductive, and the emitter voltage of the transistor 22 increases during the high level period of the output signal H of the NOR gate 21, as shown in FIG. Becomes a high level. Therefore, the trigger voltage is applied to the gate of the thyristor 7, which makes it conductive and discharges the charge in the capacitor 4 to the primary coil 5a of the ignition coil 5.
A high voltage is induced in the secondary coil 5b of the ignition coil 5, causing the ignition plug 6 to spark.

Based on the above explanation, the engine speed is shown in Figure 3.
The ignition timing is set between crank positions T ₁ and T ₂ in the rotation range higher than N ₂ and lower than N ₃ , and when the output voltage D of the operational amplifier 17 reaches the reference voltage V ₂ of the comparator 19, and the engine It will be understood that ignition takes place. Next, the operation of retarding the ignition timing with a certain slope as the engine speed increases from N ₂ to N ₃ will be explained in detail with reference to Fig. 4. It shows the triangular wave output of the output voltage D of the operational amplifier 17 within the period from crank position T ₁ to the next crank position T ₁ . Here, as described above, the point in time when the output voltage D of the operational amplifier 17 reaches the reference voltage _V2 of the comparator 19 is the ignition timing of the engine. Also, operational amplifier 17
It is also mentioned above that the discharging current I ₂ and the charging current I ₁ of the capacitor 16 that generate the output voltage D are constant values regardless of the engine speed, and the slope of the fall and rise of the output voltage D is also constant. That's exactly what I did.

Now, in Figure 4, 51, 52 and 53, 5
4 indicates the output voltage D of the operational amplifier 17, 51,
52 has an engine speed higher than N ₂ but lower than N ₃
The output voltage D at Na rotation speed is 53,5
4 is the output voltage D when the engine speed is Nb, which is lower than Na and _N3 .

At Na rotation speed, the capacitor 16 is discharged from the crank position T ₁ a where the second angle signal b is generated.
Output voltage D of operational amplifier 17 due to discharge at I ₂
falls linearly with a constant slope as shown in 51, and at the moment when this output voltage D drops below the (+) terminal potential of the comparator 18, that is, at a position shifted by an angle αa from the crank position T ₁ a, 2F.F circuit 1
4 is reset by the positive pulse voltage of the comparator 18, and from then on the capacitor 16 is charged with the current I ₁
The output voltage D of the operational amplifier 17 increases linearly with a constant slope as shown at 52. This output voltage D is the second F.F circuit 1
4 reaches the reference voltage V ₂ at a position shifted by an angle γa from the reset position, and in the process of increasing the output voltage D, the second angle signal b is reached at the next crank position T ₁ a.
As a result, the second F.F circuit 14 is set, and the capacitor 16 starts discharging again with the discharge current _I2 .

At Nb rotation speed, the capacitor 16 is similarly charged and discharged, and the output voltage D of the operational amplifier 17 similarly falls linearly with a constant slope as shown at 53, and is shifted by an angle αb from the crank position T ₁ b. At position 54, the reference voltage rises linearly with a constant slope, and at a position shifted by angle γb.
V ₂ is reached, and it descends again at the next crank T ₁ b.

In this way, in the process of increasing the rotational speed from Na to Nb, the period between crank position T ₁ a and the next crank position T ₁ a is the same as the period between crank position T ₁ a and the next crank position T ₁ b. shortened to a period.

Therefore, the angle between the position where the output voltage D at Na rotation speed reaches the reference voltage V ₂ and the next crank position T ₁ a, that is, the retard angle βa, is βa = 4π, assuming that the angle of each crank position T ₁ a is 4π. −αa−γa.

Here, ta: time Na: Number of revolutions γa=4π·ta·Na/60.

Furthermore, the angle between the position where the output voltage D reaches the reference voltage V ₂ at the Nb rotation speed and the next crank position T ₁ b, that is, the retard angle βb, is βb = 4π−, assuming that each crank position T ₁ b angle is 4π. αb−γb.

Here, tb: time Nb: Number of revolutions γb=4π·tb·Nb/60.

The angles αa and αb shown in the above equations are the charging current I ₁
Since the discharge current I ₂ is a constant value regardless of the rotation speed, the ratio of the discharge period to one rotation (4π) is constant, that is, a constant angle, and therefore αa=αb regardless of the rotation speed. Also, time ta and tb are charging current
Since I ₁ is a constant value regardless of the rotation speed, the time required for the terminal voltage of the capacitor 16 to reach the comparison voltage V ₁ is constant, that is, a constant time, and therefore ta=tb regardless of the rotation speed.

From the above relationship, the retard angle β is β=4π−α−4π・t・N/60t: time N: Number of rotations becomes.

As can be understood from the above equation, the delayed angle β is a constant angle α
It is determined as a function of the number of revolutions N by a constant time t, and therefore decreases proportionally as the number of revolutions increases from Na to Nb, which means that the number of revolutions increases from _N2 to _N3.
The same holds true when the crank position increases from _N2 to N3, so the ignition timing is retarded at a predetermined slope from crank position _T2 to _{T1 as the rotational speed increases from N2 to N3 .} Become.

In this way, the retardation angle β decreases toward zero,
When the rotation speed reaches N ₃ , the output voltage D of the operational amplifier 17 during the charging process of the capacitor 16 becomes the reference voltage.
The position at which V ₂ is reached is the maximum retarded angle position T ₁ and therefore becomes zero.

Next, the operation when the number of rotations is _N3 or more will be explained.

When the rotational speed reaches _N3 , the retardation angle β becomes zero as mentioned above, and when the rotational speed becomes more than _N3 , the output voltage D of the operational amplifier 17 becomes less than the reference voltage _V2 , so the output signal E of the comparator 19 is always This low level output signal E becomes low level.
The signal is input to the first gate of the NOR gate 20. In addition, the second gate of this NOR gate 20 has a second
Since the angle signal b is input, the output signal F of the NOR gate 20 is at a low level only during the period when the second angle signal b is at a high level, and this output signal F is a NOR
The signal is input to the first gate of the gate 21. Also
The output signal G of the first F.F circuit is input to the second gate of the NOR gate 21, and as described above, this output signal G is inverted from high level to low level by the first angle signal a of the signal coil 8. When the two-angle signal b becomes approximately zero, it is inverted from low level to high level, so the output signal H of the NOR gate 21 becomes high level only during the high level period of the second angle b of the signal coil 8, and this high level output When the signal H is input to the base of the transistor 22, the transistor 22 becomes conductive, and the collector voltage I is applied to the thyristor 7 at the maximum retard angle position _T1 , and the thyristor 7 becomes conductive. In this manner, when the rotational speed is _N3 or higher, the ignition timing becomes constant at the maximum retard angle position _T1 shown in FIG.

Next, the operation when the rotational speed is higher than _N1 and lower than _N2 will be explained. Here, the rotation speed is from N ₃ to
If it decreases to N ₂ , the retard angle β becomes larger.
This can be understood from the formula =4π-α-4π・t・N/60.

Therefore, if the rotational speed further decreases from N ₂ to N ₁ , the retard angle β becomes larger and larger. In this way the number of rotations is N ₁
In the rotation range higher than N ₂ and lower than N 2 , the output voltage D of the operational amplifier 17 is higher than the reference voltage V ₂ of the comparator 19 during the period of the delay angle β, so the output signal E of the comparator 19 becomes high level. When this high-level output signal E is input to the first gate of the NOR gate 20, the NOR gate 20 generates a low-level output signal F for a period of delay angle β, regardless of the signal from the second gate. The level output signal F is input to the first gate of the NOR gate 21. Further, the low level output signal G of the first F.F circuit shown in FIG. 2G is input to the second gate of the NOR gate 21. Therefore, NOR
The gate 21 generates a high level output signal H only during the period from the maximum advance angle position T ₂ where the first angle signal a is generated to the maximum retard angle position T ₁ where the second angle signal b is generated. The transistor 22 is turned on by the signal H, and the collector voltage I is applied to the thyristor 7 at the maximum advance angle position _T2, and the thyristor 7 is turned on. In this manner, in the rotation range where the rotational speed is higher than _N1 and lower than _N2 , the ignition timing is constant at the maximum advance angle position _T2 shown in FIG.

Next, the operation when the number of rotations is _N1 or less will be explained. When the rotational speed is N _{1 or} less, the retardation angle β is larger than the angle between each crank position T ₁ and T ₂ shown in FIG. During the period, the output signal F of the NOR gate 20 is at a low level, and this low level output signal F
is input to the first gate of the NOR gate 21. Here, the trigger level of the thyristor 10 of the first F.F circuit is set so that it will not be turned on by the first angle signal a of the signal coil 8 when the number of rotations is below _N1 , and the transistor 12 is set so as not to be turned on by the first angle signal a of the signal coil 8. It is set to conduct.
This is due to the difference in operating characteristics between the thyristor 10 and the transistor 12. Therefore, the second F.F circuit generates the low level output signal G only during the period when the second angle signal b of the signal coil 8 is input. Since this low level output signal G is input to the second gate of the NOR gate 21, the NOR gate 21
The output signal H of is at a high level only during the period when the second angle signal b of the signal coil 8 is generated, and this high level output signal H makes the transistor 22 conductive.
The collector voltage I is applied to the thyristor 7 at the maximum retardation angle position _T1 , and the thyristor 7 becomes conductive. In this way, when the rotational speed is _N1 or less, the ignition timing becomes constant at the maximum retard angle position _T1 shown in FIG.

As detailed above, according to the embodiment of the present invention, the first angle signal a corresponding to the maximum advanced angle position _T2 and the second angle signal b corresponding to the maximum retarded angle position _T1 are synchronized with the rotation of the engine. Maximum retard angle position where the second angle signal b is generated in the rotation range of rotation speed N ₁ or less using
The ignition timing is T ₁ , the rotation speed is higher than N ₁ , and N ₂
In the lower rotation range, the ignition timing is set at the maximum angle position _T2 at which the first angle signal a occurs, and the rotation speed is _N2.
In the rotation range higher than N3 and lower than _N3 , the angle at which the output voltage D of the operational amplifier 17 reaches the predetermined voltage of the comparator 18 from the maximum retard angle position _T1 is set as a constant angle α, and the time required to reach the reference voltage _V2 is set as a constant angle α. By setting a constant time t, the ignition timing is retarded with a constant slope from the maximum advance angle position T ₂ to the maximum retardation angle position T ₁ as the rotation speed increases, and the rotation speed increases.
In the rotation range of _N3 or more, the ignition timing characteristics shown in FIG. 3 can be obtained by setting the maximum retard angle position _T1 as the ignition timing.

Note that the present invention is not limited to the above-mentioned embodiments, but includes various embodiments.

For example, maximum advanced angle position T ₂ , maximum retarded angle position
T ₁ can be set arbitrarily by changing the generation timing of the first and second angle signals a and b. In addition, the slope of the retardation angle with respect to the rotation speed N is determined by the charging and discharging current of the capacitor 16.
It can be set arbitrarily by changing the constant angle α and the constant time t by adjusting I ₁ and I ₂ or by adjusting the reference voltage V ₂ . Furthermore, even at rotational speed N ₁ or less, the
If the trigger level of the thyristor 11 of the 1F.F circuit is lowered so that the thyristor 11 is made conductive by the first angle signal a, the rotation speed will be reduced as shown in Fig. 5.
Ignition timing characteristics with a maximum advance angle position T ₂ can be obtained even when N is less than ₁ . Further, although the first and second angle signals a and b utilize the positive and negative AC outputs of a single signal coil 8, independent signal coils 8a and 8b may be used, respectively, as shown in FIG. 6.

As described above, the present invention uses the first angle signal generated at the first crank position and the second angle signal generated at the second crank position delayed from the first crank position, and uses the first angle signal to reach the maximum speed. The second of the triangular wave charging and discharging outputs of the integrator that obtains the angular timing, obtains the maximum retarded timing using the second angle signal, and repeats charging and discharging at a constant current based on the second angle signal. The constant angle α is set by making the ratio of the angle at which the discharge output reaches the first predetermined value from the second crank position constant between the crank positions, and the charging output between the second crank positions reaches the first predetermined value.
The fixed time t is set by making the time to reach the predetermined value constant, and since the fixed time t is the fixed time t, the timing at which the charging output reaches the second predetermined value as the rotational speed increases is delayed, so that the engine rotation The ignition timing is retarded with a constant slope from the first crank position to the second crank position as the number increases.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing an embodiment of the present invention, FIG. 2 is an operation waveform diagram explaining the operation of the embodiment in FIG. 1, and FIG. 3 is an ignition timing characteristic diagram obtained by the circuit in FIG. 1. Fig. 4 is an operation waveform diagram for explaining the retardation operation, Fig. 5 is an ignition timing characteristic diagram showing another ignition timing characteristic diagram, and Fig. 6 is a diagram showing the generation of the first and second angle signals a and b. FIG. 7 is a main circuit diagram showing another example of a signal coil. In the figure, ignition timing control circuit, 1st F.F circuit, 8, 8a, 8b signal coil, 9, 13 diode, 10 thyristor, 11, 15, 23
is a register, 12 and 22 are transistors, 14 is a second F.F circuit, 16 is a capacitor, 17 is an operational amplifier, 18 and 19 are comparators, and 20 and 21 are
It is a NOR gate. Note that the same reference numerals in each figure indicate the same parts.

Claims (1)

[Claims] 1. A first angle signal generated at a first crank position in synchronization with the rotation of the engine; a second angle signal generated at a second crank position delayed from the first crank position; An integrator that starts discharging with a constant current based on a second angle signal, starts charging with a constant current when the discharge output reaches a first predetermined value, and generates a triangular wave-shaped charging/discharging output; the charging output of this integrator a first circuit means for generating an output when the angle reaches a second predetermined value, between the first crank position and the second crank position based on the first and second angle signals;
An engine ignition timing control device comprising: second circuit means for generating an output; and logic means for determining ignition timing by a logical operation based on the output of the first circuit means and the output of the second circuit means. 2 The integrator consists of an operational amplifier, an inverting input terminal of this operational amplifier, and a capacitor connected to the output terminal,
The capacitor receives a second angle signal and starts discharging at a constant current through the resistor, and when the first predetermined value is reached, the capacitor starts discharging at a constant current through the resistor. The engine ignition timing control device according to claim 1, wherein the engine ignition timing control device is rechargeable. 3 The first circuit means is composed of a voltage comparator, the charge/discharge output of the integrator is input to the non-inverting input terminal of this voltage comparator, and the reference voltage which is a second predetermined value is input to the inverting input terminal. 3. The engine ignition timing control device according to claim 1, wherein the engine ignition timing control device generates an output during a period in which the charging output exceeds the reference voltage. 4. The second circuit means comprises a thyristor and a transistor whose anodes and collectors are connected to each other, the thyristor being turned on in response to a first angle signal, and the transistor being turned in conduction in response to a second angle signal. An engine ignition timing control device according to any one of claims 1 to 3. 5. The engine ignition timing control device according to claim 4, wherein the thyristor remains non-conductive and only the transistor conducts when the engine rotates at low speeds. 6. The engine ignition timing control device according to claim 1, wherein the first and second angle signals are generated in a signal coil attached to a magnet generator driven by the engine.