JPS593173A - Contactless ignition device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To obtain such a contactless ignition device that a predetermined characteristic of spark delay may be obtained in a range of rotational speed below a predetermined rotational speed without the spark position being delayed, and as well the range of spark delay may be optionally set. CONSTITUTION:There is provided an ignition circuit 5 having a series circuit of the primary coil 1a of an ignition coil 1 and a capacitor 2, which is connected in parallel with a thyristor 3 that is controlled by control signals having signal widths different from each other and fed from first and second signal coils 23, 66. Further, the thyristor 3 is controlled by a control signal that is fed from a signal feed circuit consisting of a resistor 25 and a diode 26 during a period in which a transistor 27 as a signal supply controlling semiconductor switch is cut-off. Further, there is provided a control circuit including capcitors 31, 32 for controlling spark advance and spark delay, respectively, so that the suitable characteristics of spark advance and spark delay are given to the control signals.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an engine for internal combustion engines in which ignition is performed by controlling the primary current of an ignition coil using a primary current control switch that is operated by a control signal given at the ignition position of the engine. This relates to a non-contact ignition device.

In general, in internal combustion engines, it is necessary to keep the ignition position constant in the low speed range and advance the ignition position in the medium and high speed range, but depending on the engine, in order to obtain the desired characteristics, the set rotation speed ( The ignition position may be required to be retarded at higher speeds (rpm) or above, and the ignition position may be retarded in the high speed range to prevent engine overspeed.

As an ignition device that retards the ignition position when the number of revolutions exceeds a set number of revolutions, there is a known one that is equipped with a retard circuit that bypasses a part of the signal that determines the ignition position at more than the set number of revolutions from the primary current control switch. ing. However, with this ignition system, when the engine speed exceeds a certain level, the ignition position tends to be delayed even when the engine speed is below the set speed, and the maximum output cannot be extracted from the engine. Furthermore, internal combustion engines for vehicles are required to change the retard width of the ignition position at high speeds depending on the road surface conditions, etc., but it is difficult to meet such requirements with conventional ignition systems. Met.

An object of the present invention is to provide a non-contact ignition device for an internal combustion engine that prevents the ignition position from being delayed until the set rotational speed at which the retardation starts, and that allows the retardation width to be adjusted in various ways.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below along with embodiments thereof with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is an ignition coil having a primary coil 1a and a secondary coil 1b, one end of which is grounded, and 2 is a coil connected in series with the primary coil 1a. 3 is a thyristor connected in parallel to the series circuit of the capacitor 2 and the primary coil 1a as a primary current control switch; 4 is a resistor connected between the gate and cathode of the thyristor 3; P is a spark plug loaded onto the secondary coil 1b, and these constitute a capacitor discharge type ignition circuit 5. In order to provide ignition energy to this ignition circuit, an exciter coil 6 is disposed within a magnet generator driven by the engine, and one end of this exciter coil 6 is connected to a diode 7 whose cathode is connected to the connection point between the capacitor 2 and the anode of the thyristor 3. The other end of the exciter coil 6 is connected to the cathode of a diode 8 whose anode is grounded. Exciter coil 6 and diode 8
A diode 9 whose anode is grounded is connected in parallel to both ends of the series circuit, and a thyristor 10 whose cathode is grounded is connected in parallel to both ends of the diode 8. A Zener diode 11 or its anode is connected in parallel between the anode and gate of the thyristor 10 with its anode facing the gate of the thyristor, and a resistor 12 is connected in parallel between the gate and cathode. Further, the anode of the evening diode 13 is connected to the anode of the thyristor 10, and the anode of the evening diode 13 is connected to the anode of the thyristor 10.
A power supply circuit 15 is constituted by a power source diode 11, a resistor 12, a diode 13, and a capacitor 14 having a sufficiently large capacitance between the cathode 3 and the ground.

When the exciter coil 6 of the power supply circuit generates an output in the direction of the solid arrow shown in the figure, the capacitor 2 is charged through the diode 7 to the polarity shown.

Next, when a control signal is applied to the gate of the thyristor 3, the thyristor 3 becomes conductive, and the charge in the capacitor 2 is discharged through the thyristor 3 and the primary coil 1a. Since this discharge occurs in an extremely short period of time, a current suddenly flows into the primary coil of the ignition coil 10, causing a large magnetic flux change in the iron core of the ignition coil, which induces a high voltage in the secondary coil lb, causing the spark plug P A spark is generated. Therefore, in the ignition circuit 5, the ignition position can be controlled by controlling the position at which the control signal is applied to the thyristor 3. The ignition circuit 5 used in the present invention may be of any type as long as it suddenly changes the primary current of the ignition coil 1 to perform the ignition operation by operating a primary current control switch, and may be of the type such as a current cut-off type ignition circuit. ignition circuit may be used.

In the half cycle in which the voltage in the direction of the dashed arrow shown in the figure is induced in the exciter coil 6 in the power supply circuit 15,
A power supply capacitor 14 is charged through the diode 13 to the polarity shown. When the output of the exciter coil 6 in the direction of the dashed arrow reaches a certain value, the Zener diode 11 becomes conductive, the thyristor 10 becomes conductive, and the output of the exciter coil 6 is bypassed from the capacitor 14. Therefore, the capacitor 14 is always charged to a constant voltage, and this capacitor is used as a power source for a control circuit to be described later.

An ignition position control circuit 20 is provided to control the ignition position fit according to the engine rotational speed (rl)m.

This control circuit includes a first signal coil 23 provided in a signal generator that rotates synchronously with the engine.
3 outputs at least one cycle of signal eg (see Figure 2 C) per one ignition cycle of the engine (the period in which each cylinder is ignited once and then the next ignition is performed). In the example, this first signal coil 23 first sends a signal e in the direction of the dashed arrow shown in the figure (hereinafter, this half cycle is referred to as a negative half cycle) at the position of the front angle θl of the top dead center TDC.
Then, at the top dead center angle θ2, a signal eg2 is generated in the direction of the solid arrow shown in the figure (hereinafter, this half cycle will be referred to as a positive half cycle). One end of the signal coil is grounded, and the other end is connected to the gate of the thyristor 3 through a diode 24. Here, the diode 24 is installed in such a direction that its cand is located on the cand side of the thyristor 3, and the positive half-cycle signal eB2 generated after the signal coil 23 is applied to the gate of the thyristor 3 as a control signal through the diode 24. It is now possible to

On the other hand, one end of a resistor 25 is connected to the non-grounded terminal of the power supply capacitor 14, and the other end 25a of the resistor 25 is connected to the gate of the thyristor 3 through a diode 26 in the same direction as the diode 24. The resistor 25 and the diode 26 constitute a signal supply circuit that supplies a control signal to the thyristor 3 separately from the signal coil 23, and when a predetermined condition described later is met, a signal is supplied from the power supply circuit 159Ill through the resistor 25 and the diode 26. A control signal is given to the thyristor 3.

The collector of a transistor 27 as a semiconductor switch for signal supply control whose emitter is grounded is connected to the other end 25a of the resistor 25, and the pins of the transistor 27 are connected to the non-grounded terminal of the power supply capacitor 14 through a resistor 28. The pace of the zero transistor 27 is connected to the cand of a diode 29 whose anode is grounded, and is also connected to the anode of the thyristor 30A, and the cand of the thyristor 30A is connected to the non-grounded terminal of the signal coil 23. A resistor 30B is connected in parallel between the gate and anode of the thyristor 30A, and a Zener diode 30C is connected in parallel between the gate and anode. The thyristor 30A to the Zener diode 30C constitute a thyristor switch 30 that becomes conductive when the negative direction output of the signal coil 23 exceeds a certain level.

The transistor 27 is turned on by being supplied with a pace current from the power supply circuit 15 through the resistor 28 during a period other than the period in which a negative half-cycle signal is generated in the No. 48 coil 23.
A control signal applied from the power supply circuit 15 is passed to the ground side through the resistor 25 and bypassed from the thyristor 3. When the negative direction output of the signal coil 23 reaches a certain level, the Zener diode 30C becomes conductive and an ignition signal is given to the thyristor 30A, thereby making the thyristor 30A conductive. When the thyristor 30 becomes conductive, the base-emitter of the transistor 27 is reverse biased due to the forward voltage drop of the diode 29, so the transistor 27 is cut off, and the control signal 4'ts supplied through the resistor 25 is applied to the thyristor 3. allow it to be given to

As mentioned above, the period during which the transistor 27 is in the cut-off state (
During the period during which the signal coil 23 generates a negative half-cycle signal of a certain level or higher, a control signal can be given to the thyristor 3 through the resistor 25 and the diode 26.
In order to provide further conditions to the supply of this control signal to provide lead angle characteristics and retard angle characteristics, the first capacitor (advance angle control capacitor) 31 and the second capacitor (retard angle control capacitor) 32 are connected. A circuit is provided that uses charging and discharging to control the supply position of the control signal. That is, one end of the first capacitor 31 is grounded, and the other end of the first capacitor 31 is connected to the cand of the diode 33. The anode of the diode 33 is connected to the source of a field effect transistor (hereinafter referred to as FET) 35 through a variable resistor 34, and the drain of the FET 35 is connected to the power supply capacitor 14.
connected to the non-grounded terminal of the The gate of FET35 is connected to the anode of diode 33, and FET
35 and the variable resistor 34 constitute a constant current circuit 20A. There is also an FET in the cand of diode 33.
The drain of FET 36 is connected, and the source of FET 36 is connected to the collector of transistor 38 through variable resistor 37.

The gate of FET36 is connected to variable resistor 37 and transistor 3.
These FET36 are connected to the connection point with the collector of 8.
and the variable resistor 37 constitute a constant current circuit 20B. Transis! ! The collector of 38 is still connected to the anode of diode 33, and the emitter is grounded. A series circuit of resistors 39 and 40 is connected in parallel between the collector and emitter of the nJ transistor 27, and the pace of the transistor 38 is connected to the connection point of the resistors 39 and 40. Transistor 38 becomes conductive when transistor 27 is turned off by applying a base current through resistors 25 and 39, and becomes turned on when transistor 27 is turned on. The first capacitor 31 is charged with a constant current by the power supply circuit 15 through the υFET 35, the variable resistor 34, and the diode 33 to the illustrated polarity. Further, when the transistor 27 is cut off and the transistor 38 is turned on, the first capacitor 31 is discharged with a constant current through the FET 36, the variable resistor 37, and the transistor 38.

During this discharge, the current supplied from the power supply circuit 15 through the FET 36 and the variable resistor 34 is bypassed from the first capacitor 31 through the transistor 38.
It does not affect the discharge of the capacitor 31. FET3
6. The variable resistor 37 and the transistor 38 constitute a discharge circuit for the first capacitor 31.

Further, a reference voltage generation circuit 20E consisting of a series circuit of a resistor 41 and a Zener diode 42 is connected in parallel to both ends of the power supply capacitor 14, so that a reference voltage Vrl is obtained across the Zener diodes 4 and 2. . This reference voltage Vr is the terminal voltage V of the first capacitor 31
The output terminal 43a of the first comparison circuit 43 indicates that the terminal voltage V c 1 of the first capacitor 31 is the reference voltage V.
When r is greater than 1, it becomes the ground potential. p1 When the terminal voltage Vcl of the first capacitor 31 becomes lower than the reference voltage Vrl, it becomes a high potential. The output terminal 43a of this first comparison circuit 43 is connected to the anode of the diode 26, and when the output terminal 43a of this comparison circuit is at ground potential, the supply of the control signal to the thyristor 3 is blocked, and the output terminal The control signal is allowed to be supplied to the thyristor 3 when the potential of the thyristor 43a becomes high.

The second capacitor 32 is also connected to the non-grounded terminal of the power supply capacitor 14 through a constant current circuit 20C consisting of an FET 44 and a variable resistor 45, and a diode 46.
Constant current charging is performed by the output of the power supply circuit 15. Terminal voltage VC of the second capacitor 32! is the reference voltage Vr+ obtained across the Zener diode 420
The output terminal 49a of the second comparison circuit 49 is connected to the second capacitor 32.
When the terminal voltage Vc2 of the second capacitor is lower than the reference voltage Vr+, it becomes a ground potential, and when the terminal voltage Vex of the second capacitor becomes equal to or higher than the reference voltage Vr1, it becomes a high potential. The output terminal 49a of the comparator circuit 49 is connected to the anode of the diode 26, so that when the output terminal 49a becomes a high potential, supply of a control signal to the Cyrisk 3 is allowed.

In order to instantaneously discharge the charge in the first capacitor 31 and reset the capacitor, a thyristor 51 whose cand is grounded is provided, and the anode of this thyristor 51 is connected to the non-grounded terminal of the capacitor 31. The gate of the thyristor 51 is connected to a voltage dividing point of a voltage dividing circuit consisting of a series circuit of resistors 52 and 53 connected in parallel to the signal coil 23, and the thyristor 51 and resistors 52 and 53 are connected to the voltage dividing point of the voltage dividing circuit. 20D is configured.

In order to be able to adjust the retard width, a retard width determination circuit 2 is provided.
0F is provided. This circuit includes a transistor 60 whose emitter is grounded, and the collector and base of this transistor are connected to the non-grounded terminal of the power supply capacitor 14 through resistors 61 and 62, respectively. The collector of transistor 60 is also connected to a second
A diode 64 whose anode is connected to the ground side is connected in parallel to the base emitter ffJ of the transistor 600.

The transistor 60 is connected to one end of a second signal coil 66 through a silicon risk switch 65, and the other end of the signal coil 66 is grounded.

A voltage dividing circuit consisting of a series circuit of resistors 67 and 68 is connected in parallel to both ends of the second signal coil 66, and a thyristor 69 for resetting the second capacitor 32 is connected to the voltage dividing point of this voltage dividing circuit. Gate is connected. The cand of the thyristor 69 is grounded, and the anode is connected to the non-grounded terminal of the second capacitor 32. The thyrisk switch 65 consists of a thyristor 65A, a zener diode 65B, and a resistor 65C, and when the output of the signal coil 66 in the negative half cycle (the half cycle that generates the output in the direction of the dashed arrow in the figure) exceeds a certain level, the Zener When the diode 65B becomes conductive, the thyristor 65A becomes conductive.

The non-grounded terminal of the second signal coil 66 is connected to the gate of the thyristor 3 via a diode 70. The signal coil 66 is provided in a signal generator that rotates in synchronization with the engine, and as shown in FIG.
Signal e'8. of negative half cycle at position 1. is generated, and then a positive half-cycle signal e'8. is generated at the position of angle θ3 (>θ2) before top dead center. occurs. When the negative direction output of the signal coil 66 exceeds a certain level and the thyristor 65A becomes conductive, the forward voltage drop of the diode 64 causes a reverse bias between the pace emitters of the transistor 60, so that the transistor 60 is cut off, and the transistor 65A becomes conductive. The potential of the collector of 60 becomes high level as shown in FIG. 2H. Next, when the negative direction output of the signal coil 66 becomes below a certain level, the thyristor 65A is cut off and the transistor 60 becomes conductive. If the rise of the negative direction output of the signal coil 66 is made fast enough, the transistor 60°
The period in which is in the cut-off state substantially corresponds to the period 01 to θ3 of the negative half cycle of the signal coil 66. When the positive output of the second signal coil 66 rises at the angle θ3,
Since the thyristor 69 becomes conductive, the charge in the second capacitor 32 is instantly discharged, and the second capacitor 32 is reset. Thereafter, the second capacitor 32 is charged through the constant current circuit 20C, but a part of the charging current is passed through the resistor 63 and the transistor 60 to the capacitor 3.
2, the terminal voltage of the second capacitor 32 rises non-linearly as shown in the second diagram.

When the transistor 60 enters the cutoff state at the angle θl, the charging of the second capacitor 32 switches to constant current charging.
Its terminal voltage rises linearly and then rises to a second level at angle θ3.
When the thyristor 69 becomes conductive due to the positive output of the signal coil 66, the second capacitor 32 is reset and the terminal voltage thereof becomes zero as described above. In this embodiment, transistor 60. Resistance 63. The capacitor charging circuit that adjusts the charging of the V-second capacitor 32 by the diode 64 and the silicon switch 65 is in an OFF state. In addition, the thyristor 69 and the resistors 67 and 68 cause the second signal coil to rise when the positive output of the second signal coil rises.
A reset circuit 20G is configured to reset the capacitor.

In the above ignition device, a control signal is given to the thyristor 3 in one of the following cases.

(a) When a positive half-cycle signal is induced in the first signal coil 23.

(b) When the transistor 27 is in a cut-off state and the output terminal 43a of the first comparison circuit 43 and the output terminal 49a of the second comparison circuit 49 are at a high potential.

(c) The second signal coil 66 has a positive half cycle (N
When the number is induced.

Next, the operation of the embodiment shown in FIG. 1 will be explained using signal waveforms i shown in FIGS. 2A to 2J. Assuming that the magnet generator in which the exciter coil 6 is arranged has four poles and is directly connected to the output shaft of the engine, the exciter coil 6 has two cycles per revolution as shown in Fig. 2AK. AC voltage V
e induces.

The negative half cycle of this voltage is originally a waveform shown by a broken line in the figure, but in the above embodiment, when the voltage of the negative half cycle reaches a level that makes the Zener diode 11 conductive, the thyristor 1o becomes conductive. Since the voltage is short-circuited,
As shown by the solid line in the figure, the waveform is limited to a certain voltage. The angle θ is also the top dead center TDC of the engine. When the positive half-cycle voltage of the exciter coil 6 rises at the previous position, the capacitor 2 is charged to the polarity shown through the diode 7, and its terminal voltage Vc changes as shown in FIG. 2B. The first signal coil 23 is the exciter coil 6
At the position of the top dead center rudder angle θ, which is set near the fall of the second positive direction exit, the negative direction signal e! ! + is generated, and then a positive direction signal es is generated at the top dead center rudder angle θ2 position. Engine rotation speed N (rpm) is idling rotation speed N
, to the set value N, (>N, ), the negative direction signal eB output from the signal coil 23,
The transistor 27 is in a conductive state because the voltage does not reach a level that can cut off the transistor 27. Therefore, in the low speed range of the engine, no control signal is applied to the thyristor 3 from the power supply circuit 15 through the resistor 25 and diode 26, and all current supplied from the power supply circuit through the resistor 25 is bypassed from the thyristor 3 through the transistor 27. Ru. Next, the positive direction signal eB of the signal coil 23 generated at the angle θ reaches a peak at the top dead center rudder angle θ4, and when this peak value reaches the gate trigger level of the thyristor 3, the thyristor 3 Conduct. At this time, the charge in the capacitor 2 is discharged through the thyristor 3 and the primary coil 1a, and an ignition operation is performed. The positive direction signal eg of the signal coil 23 indicates the engine rotation speed from N to N! As the rotation speed increases, the phase at which the positive direction signal eB reaches the trigger level of the thyristor 3 gradually advances as the rotation speed increases, as shown in FIG. Positive direction signal e3 of signal coil 23! If the signal width is narrowed, the fluctuation range of the ignition position in this low speed region is small.

When the engine speed N reaches the set value N, the negative direction signal e6. of the first signal coil 23 is activated. reaches a level that turns off transistor 27, so transistor 27 turns off.

At this time, the collector-emitter voltage of the transistor 27 changes as shown in the second diagram. On the other hand, the first capacitor 31 is connected to the FE by the power supply circuit 15.
It is charged with a constant current through T35, and when the rotation speed reaches the set value N as described above and the transistor 27 is cut off, the transistor 38 becomes conductive, so that the first capacitor 31 is discharged with a constant current through the FET 36. Therefore, the waveform of the terminal voltage Vc of the first capacitor 31 in the region of rotation speed N2 or higher is 1.0 as shown in FIG. 2E. After rising at a constant slope from the position of angle θ, from angle θ, to θ
The waveform repeats υ, descending at a constant slope until , and returns to zero at the next angle θ, which is exactly 360° rotated from the charging start position θ. - Meanwhile, the second capacitor 3
2 is charged with a constant current supplied from the power supply circuit 15 through the FET 44, the variable resistor 45, and the diode 46. As described above, during the period when the transistor 60 is conductive, a part of the charging current of the capacitor 32 flows through the resistor 63 and the transistor 60, so that the capacitor 32
The charging characteristics of the capacitor are approximately determined by a time constant determined by the capacitance of the capacitor and the resistance value of the resistor 63.

On the other hand, during the period when the negative half-cycle signal is induced in the first signal coil 23 and the transistor 60 is cut off (the period from θN to θ), the charging current AI of the capacitor 32 is not bypassed, so it is passed through the constant current circuit 20c. All of the applied constant current is supplied to the capacitor 32, and the capacitor 32 is charged at a steep constant slope. Therefore, the waveform of the terminal voltage Vc2 of the second capacitor 32, as shown in FIG. ,
It becomes a drum shape that is reset at the angle θ and returns to zero.

When the engine speed N exceeds the set value N, the terminal voltage Vc of the first capacitor 31 becomes equal to or less than the reference voltage Vr at a position θy where the 'r phase is more advanced than the angle θ. , as shown in FIG. 2F, the output terminal 43a of the first comparator circuit 43 becomes high potential at the position θy. The position of θy advances as the engine speed increases. In this embodiment, the rotation speed N is a set value Ns (> N2)
It is set so that when K is reached, the position of θy between and coincides with the position of angle θ.

On the other hand, the terminal voltage Vc of the second capacitor 32 becomes equal to or higher than the reference voltage Vr at the position of the angle θX before the upper hole point, and as shown in FIG.
As shown in , the output terminal 49a of the second comparator circuit 49 becomes high potential at the position θX.

As the engine speed increases, the time required for one rotation of VC becomes shorter, and the capacitor 32 is charged! As the voltage decreases, the position of θX lags toward the top dead center TDC side as the engine speed increases. When the position of θX reaches the angle θ
1 position, and the rotation speed N is the set value Na (> N4
) When the angle K is reached, the position of θX matches the position of the angle θ, 0 Since it is set as above, the engine speed N is within the range of N, ≦N≦N. In a certain medium to high speed range, a condition is established in which a control signal is given to the thyristor 3 from the power supply circuit 15 through the resistor 25 and the diode 26 at the angle θy, and the ignition operation is performed at the angle θy. The position of θy advances as the rotational speed increases, and when the set rotational speed N3 is reached, the position of the angle θ before the upper hole point is reached. When the rotation speed increases further, θ
Although the position of y advances further, since the transistor 27 is conductive at a position further advanced than the position of the angle θ1, no control signal is given to the cyrisk 3. Therefore, the ignition position advances only to the position of angle θ, and the set rotation speed N
, to N4, ignition is performed at this angle θ1.

When the engine speed reaches the set value N4Vc, the position θX at which the output terminal 49a of the second comparator circuit 49 rises to a high potential becomes 0.
1Vc, and as the rotation speed increases further, the position of θX will further lag toward the top dead center, so the position where the conditions for giving the control signal to the thyristor 3 from the power supply circuit 15 side are satisfied is the position of θX. Yes, the ignition operation will take place at this position. Therefore, in the range from the set rotational speed N4 to N, the ignition position is delayed as the rotational speed increases. When the rotation speed exceeds the set rotation speed N6 and the position of θX becomes closer to the top dead center than the position of the upper hole point front angle θ, a control signal is sent from the 11 mark circuit 15 at the position of θX. A control signal comes to be given to the syringe nut 3 by the positive direction signal e'BM of the second signal coil 66 at the position of the angle θ before the application of the control signal e'BM. Therefore, the ignition position in the range of the set rotational speed N3 or higher is fixed at the position θ. Through the above operation, the advance/retard characteristic shown in FIG. 3 can be obtained.

In the above embodiment, the maximum advance angle position θ1 is determined by the rising position of the negative direction signal eB of the signal coil 23;
By appropriately setting the magnetic pole structure of the signal generator and its mounting position, the maximum advance angle position θ1 can be easily set to a desired position. If the structure of the signal generator is kept constant, this maximum advance angle position θ1 will remain unchanged.
This eliminates the problem of the maximum advance angle position varying depending on the characteristics of the starting engine, unlike in the conventional case. Moreover, in the high speed range of the engine, the ignition position can be maintained at the maximum advance position without being delayed. Furthermore, the ignition position (maximum retardation position) θ at the time when the retardation ends.

is determined by the rising position of the positive direction signal eW of the second signal coil 66, so by appropriately setting the rising position of this positive direction signal ei, the retard width θ1-θ can be arbitrarily set. I can do it. Further, since the fluctuation range of the ignition position in the low speed region can be suppressed to a small value, the startability of the engine can be improved.

Furthermore, by appropriately setting the charging time constant of the first and second capacitors and the level of the reference voltage, each set rotation speed can be easily adjusted. 20c, if a charge adjustment circuit is provided that bypasses a part of the current supplied to the retard control capacitor 32 to adjust the charge of the capacitor, the retard characteristics can be given a degree of freedom. Various retard characteristics can be obtained.

In the above embodiment, the positive direction signal eAyu outputted by the second signal coil 66 is in the rotation range where the engine rotation speed is equal to or lower than the rotation speed N□ (see Fig. 3) at which the engine rotation speed is advanced at the 08 inch ignition position. In this case, the level that triggers thyristor 3 is not reached. If it is not possible to make such a setting based only on the output characteristics of the signal coil 66, insert a Zener diode or the like in the circuit between the second No. 48 coil 66 and the gate of the thyristor 3 in Fig. 1. Rotation speed N
The positive direction signal of the second signal coil 66 is made not to trigger the thyristor 3 in a rotation range of 23 or less.

In the above embodiment, a characteristic is obtained in which the angle is linearly advanced and then linearly retarded, but after the angle is advanced in a stepwise manner, the angle is linearly retarded by a predetermined width at or above the set rotation speed. Also included within the scope of the present invention are circuits that obtain the following. For example, in the embodiment shown in FIG. 1, if the constant current circuit 20B, the transistor 38, and the resistor 39°40 that constitute the discharge circuit of the first capacitor 31 for advance angle are omitted, the result will be as shown by the broken line in FIG. At the set rotational speed N, the angle is advanced stepwise from the angle θ to θ, and at the set rotational speed N4 or higher, the angle is retarded in the same manner as described above.

In the embodiments described above, a SIRISC is used as a reset switch for instantaneously discharging a capacitor, but the SIRISC circuit may be constructed using other SIRISC switches such as transistors.

In the above example, the terminal voltages Vc and Vc of the first and second capacitors are compared with a common reference voltage Vr, but both terminal voltages are compared with respective reference voltages. Good too.

In the above embodiment, the power supply circuit 15 using the negative direction output of the exciter coil is used as a power supply for supplying a control signal to the SIRISK (primary current control switch) and a power supply for charging the first and second capacitors. However, these 11. A battery can also be used as the uf.

As described above, according to the present invention, a predetermined retard characteristic can be obtained without retarding the ignition position in a rotation range below the set rotation speed. However, since the retard width can be arbitrarily set, there is an advantage that various retard properties can be easily obtained depending on the requirements of the load side of the engine, such as the running conditions of the vehicle.

[Brief explanation of drawings]

Fig. 1 is a connection diagram showing an embodiment of the present invention, Fig. 2 A to J
1 is a signal waveform diagram of each part in FIG. 1, and FIG. 5 is a diagram showing an example of the advance/retard property obtained by the embodiment of FIG. 1. DESCRIPTION OF SYMBOLS 1... Ignition coil, 3... Thyristor, 5... Ignition circuit, 6... Exciter coil, 15... Electric circuit, 23... Signal coil, 27... Transistor,
31...First capacitor (advance angle control capacitor)
, 32... Second capacitor (retard angle control capacitor), 35.36.44... FFJT, 38... Transistor, 42.11... Zener diode, 43
...first comparison circuit, 49...second comparison circuit, 6
o...Dosing resistor, 63...Resistor, 66...Second signal coil, 57.68...Resistor, 69...Thyristor. Figure 3 1-→'-NCrpm)

Claims (1)

[Claims] A non-contact ignition device for an internal combustion engine that is operated by a control signal given at the ignition position of the engine and controls the primary current of an ignition coil by a primary current control switch to perform an ignition operation. 1 ignition cycle per υ1
a first signal coil provided to generate a cycle signal and supply a later generated half-cycle signal to the primary current control switch as the control signal; and signal generation of the first signal coil. The primary current control switch is configured to generate a one-cycle signal having a narrower signal width than the first signal coil at the same position as the first signal coil, and to apply a half-cycle signal generated later to the primary current control switch as the control signal. a second signal coil, and a signal supply circuit that supplies a control signal to the primary current control switch separately from the control signals supplied by the first and second signal coils; The control signal provided from the circuit is provided to be bypassed from the primary current control switch, and is coupled to the signal coil so as to be kept in a cut-off state by a half-cycle signal generated at the tip of the signal coil. a semiconductor switch for signal supply control; a retard control capacitor that is charged to one polarity through a constant current circuit; and the capacitor is discharged at the rising edge of a half-cycle signal generated after the second signal coil. a reset circuit, which compares the terminal voltage of the capacitor with a reference voltage and prevents the control signal from being applied from the signal supply circuit when the terminal voltage of the capacitor is lower than the reference voltage; a comparison circuit that allows the control signal to be applied from the signal supply circuit when the voltage exceeds the reference voltage; The control signal given to the current control semiconductor switch is applied to the primary current control semiconductor switch in the rotational speed range below which the ignition position of the engine is advanced to the rising position of the half cycle generated after the second signal coil. An ignition device for an internal combustion engine, characterized in that the ignition device is set so as not to reach a level that would trigger a switch.