JPH09151836A - Ignition device for capacitor discharge type internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ignition device for a capacitor discharge type internal combustion engine having a function to prevent reversing of the engine. SOLUTION: A signal generator 7 is brought into a state to generate pulse signals Vs1 and Vs2 at a positive semicycle section adjoining a single phase AC voltage e1 fetched from a section between the two-phase output terminals 1u and 1v of a magnet generator 1 during forward rotation of an internal combustion engine. A generator output polarity discriminating circuit 11 is provided to generate a polarity signal different in a state with polarity of the single phase AC voltage e1. When the rotation speed of the engine is below a set value, the rotation direction of the engine is decided by watching the state of a polarity discrimination signal when the pulse signal Vs2 is generated. When it is decided that the engine is reversed, an engine is failed in ignition by prohibiting an ignition signal from being inputted to an ignition circuit 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device for a capacitor discharge type internal combustion engine which controls an ignition position by using a microcomputer.

[0002]

2. Description of the Related Art In recent years, various demands have been made for internal combustion engines such as purification of exhaust gas, improvement of fuel consumption, reduction of noise, and improvement of output. In order to meet these demands, BACKGROUND ART Digitally controlled ignition devices that precisely control the ignition position of an internal combustion engine using a microcomputer have come into wide use.

A capacitor discharge type ignition device for an internal combustion engine in which an ignition position is controlled by using a microcomputer is provided with, for example, an ignition coil, an ignition energy storage capacitor provided on the primary side of the ignition coil, and an ignition signal. An ignition switch that is turned on to discharge the electric charge of the capacitor to the primary coil of the ignition coil, and discharges the ignition energy storage capacitor to generate a high voltage for ignition in the secondary coil of the ignition coil. Circuit and reference position set to a rotation angle position that is ahead of the dead center of the internal combustion engine (rotation angle position corresponding to the top dead center of the piston) and a position that is behind the reference position And a signal generator that generates first and second pulse signals at the ignition position at extremely low speed, and a generator based on the generation cycle of the output pulse of the signal generator. Rotation speed detecting means for detecting the rotation speed of the engine, ignition position calculating means for calculating the ignition position at the detected rotation speed, and ignition at the position of generation of the second pulse signal generated by the signal generator when the engine is extremely low speed. When the command signal is generated and it is detected that the signal generator has generated the pulse signal at the reference position during steady operation of the engine, the ignition position calculation means calculates and calculates the ignition position. The ignition command signal generating means generates an ignition command signal when the ignition position is measured, and the ignition signal output circuit which gives the ignition signal to the ignition circuit when the ignition command signal is generated. The ignition position calculation means calculates the ignition position at each rotation speed in the form of the time required for the engine to rotate from the reference position to the ignition position at that rotation speed. The ignition command signal generating means starts measurement of the ignition position calculated when the reference position is detected from the first pulse signal output from the signal generator, and when the measurement of the ignition position is completed, the ignition command signal is generated. To occur.

In this specification, the "position" when referring to the ignition position, the signal generation position, etc. means the rotational angle position of the output shaft (usually the crankshaft) of the engine, and is actually expressed by the rotational angle. It

In both the two-cycle engine and the four-cycle engine, if the compression ratio is high, the piston may be pushed back at the time of starting and the engine may rotate in the reverse direction. This phenomenon is called Ketchin. There are the following two causes of this ketchin.

(A) When the crankshaft is not rotating at the time of starting the engine, the piston is pushed back before the ignition position is reached due to the increase in the internal pressure of the cylinder, and the engine is reversed.

(B) When the crankshaft is not rotating at the time of starting the engine, ignition is performed at the ignition position before top dead center, and the piston is pushed back by the explosion pressure generated at that time to cause the engine to move. Reverse.

Since the reverse rotation caused by the cause of the above (a) is not due to the explosion of fuel, a large force does not act on the starting device of the engine at the time of reverse rotation, and a big problem does not occur. However, if the ignition operation is performed in the process of reverse rotation after the piston is pushed back by the pressure in the cylinder and reverse rotation occurs, the reverse rotation of the engine may be maintained.

Since the reversal caused by the cause of the above (b) is due to the explosion of the fuel, a large force acts on the starter during the reversal. When such a reversal occurs, there is a risk that the driver may be injured if the starting device uses a human power such as a kick starter or a rope starter. Further, when the starting device is an electric starter, a large force is applied to the gear mechanism that connects the starter motor and the crankshaft during reverse rotation, which may damage the gear mechanism.

As described above, if the ignition operation is performed when the engine is reversed, the driver may be injured or the starter may be damaged. Therefore, when the engine is reversed, the ignition device is activated. It is necessary to stop the ignition operation of the engine to misfire the engine.

As an ignition device having a function of stopping the ignition operation when the engine rotates in the reverse direction, the rotation of the engine is determined by the phase relationship between the output voltage of the magneto generator attached to the internal combustion engine and the output pulse of the signal generator. Detects the direction and allows the ignition operation when it is detected that the engine is rotating normally in the entire engine speed range, and prohibits the ignition operation when it is detected that the engine is rotating in the reverse direction. What has been done is proposed (actual fair 3-11421).

[0012] In this already proposed ignition device, a capacitor discharge type ignition circuit that operates as an ignition power source using an exciter coil provided in a magnet generator driven by an internal combustion engine is used. A pulse signal of negative polarity and a pulse signal of positive polarity are generated at a reference position for starting position measurement and a rotation angle position (ignition position in an extremely low speed region) set at a position delayed from the reference position, respectively. To use. Then, at the time of normal rotation of the internal combustion engine, the signal generator outputs two pulse signals of a negative polarity pulse signal and a positive polarity pulse signal while the exciter coil outputs a positive half cycle voltage. That is, when the exciter coil outputs a negative half-cycle voltage and the signal generator detects a state in which two pulse signals of negative polarity and positive polarity are generated, the engine is reversed. As a matter of fact, the ignition operation is prohibited.

[0013]

In an ignition device in which the ignition position is controlled by a microcomputer, information on a reference position for starting measurement of the ignition position, information on the ignition position in a low speed region of the engine, and rotation of the engine. As a signal generator used to obtain speed information, an inductor including a rotor equipped with a reluctor (inductor) usually having a predetermined polar arc angle and attached to a crankshaft of an engine, and a signal generator. Shaped generator is used. The signal generating electron has a signal coil wound around an iron core having a magnetic pole portion facing the surface of the rotor on which the reluctor is provided, and a permanent magnet magnetically coupled to the iron core. The first and second pulse signals having different polarities are induced in the signal coil due to changes in the magnetic flux generated in the iron core at the time of starting the facing to and at the time of ending the facing.

When the signal generator as described above is used, the interval between two pulse signals generated in the signal coil during one revolution of the engine is approximately equal to the polar arc angle of the reluctor. Of the first pulse signal and the second pulse signal generated by the signal generator, the generation position of the second pulse signal is
Since the ignition position is a low speed region (fixed ignition position), it is determined according to a request from the engine side. Further, since the generation position of the first pulse signal is the reference position for starting the measurement of the ignition position calculated by the microcomputer, it is at least the maximum advance position of the ignition position or further advanced than the maximum advance position. Must be in position. That is, the polar arc angle of the reluctor must be set to be at least larger than the advance angle width of the ignition position. In many cases, the polar arc angle of the reluctor is set to about 30 degrees, and the generation interval of two pulse signals induced in the signal coil during one rotation of the engine is about 30 degrees.

Therefore, when the two pulse signals output from the signal generator are generated in the positive half cycle section of the output voltage of the exciter coil, it is determined that the internal combustion engine is rotating normally, and the two pulse signals are output. When the method is used to determine that the engine is rotating in the reverse direction when occurs in the negative half cycle section of the output voltage of the exciter coil, the angular width of the positive and negative half cycle section of the exciter coil is 30 degrees or less. Also needs to be large.

As the magneto generator provided with the exciter coil, one having 4 poles or 8 poles is usually used, and when these magnet generators are used, the angular width of the half cycle section of the output voltage of the exciter coil is 90. Since it is 45 degrees or 45 degrees, it is sufficiently possible to generate two pulse signals from the signal coil during the half cycle of the output voltage of the exciter coil, and the phase relationship between the output of the signal coil and the output of the exciter coil is sufficient. It is possible to determine the rotation direction of the engine by.

Recently, however, it has become necessary to reduce the size and increase the output of a magnet generator installed in an internal combustion engine. Therefore, an exciter coil having a large number of turns and a large size is used as an ignition power source. There is a tendency that all the power generation coils in the magnet generator are used as power generation coils for charging the battery, and the ignition device and other electric components are driven by the output of the battery. In this case, in order to increase the output of the magnet generator, the number of poles of the magnet generator is often larger than eight, and normally a magnet generator having 12 or more poles is used.

When all the generator coils in the magnet generator are used for charging the battery, the generator coils in the magnet generator are connected in three phases, and the three-phase output is a full-wave rectifier circuit having a voltage adjusting function. In many cases, the configuration is such that the battery is supplied to the battery through the battery charging circuit.

When such a configuration is adopted, for example, a single-phase AC voltage is extracted from both ends of a two-phase generator coil among three-phase star-shaped generator coils, and the single-phase AC voltage and signal generator are generated. It is conceivable to detect the rotation direction of the engine based on the phase relationship with the output pulse of the machine.

However, when a magnet generator with 12 poles or more is used, the angular width of the half-cycle section of the single-phase AC output voltage obtained from the generator is 30 degrees or less, so that the signal in that half-cycle section is Two pulse signals (3
It occurs at 0 degree intervals). In this case, it is conceivable that the generation intervals of the two pulse signals generated at the reference position and the ignition position at extremely low speed are smaller than 30 degrees, but the ignition position in the low speed region is slightly smaller than the top dead center of the engine. It is necessary to set it to a position advanced to the above position, and it is necessary to set the reference position to the maximum advance angle position of the ignition position or a position further advanced than it, so the generation interval of the two pulse signals is unnecessarily reduced. It is not possible.

Even when a magnet generator having a smaller number of poles than 12 poles is used, if the advance width of the ignition position is larger than 30 degrees, the rotation direction of the engine can be detected by the conventional method. You may not be able to For example, in the case of a 4-cycle engine, it may be necessary to have an advance width of 45 degrees or more. In this case, if an 8-pole magnet generator is used, the positive half cycle of the output of the magnet generator will be used. Since the two output pulses of the signal generator cannot be generated in the section of 1, the conventional method cannot detect the rotation direction of the engine.

Therefore, by expanding the polar arc angle of the reluctor, as shown in FIG. 6, two pulse signals are provided in each of two adjacent positive half-cycle sections of the output of the magneto-generator when the engine is rotating normally. It is possible to generate. In the example of FIG. 6, the magnet generator is configured with 12 poles, and as shown in FIG. 6A, outputs an AC voltage of 6 cycles per rotation. The angular width of the half-cycle section of the output voltage e1 of this magnet generator is 30 degrees. In this example, as shown in FIG. 6 (B), the polar arc angle of the reluctor of the signal generator is expanded to 60 degrees, and the signal generator has a negative polarity generated at the reference position and the ignition position at extremely low speed. The first pulse signal S1 and the second pulse signal S2 of positive polarity are set at an interval of 60 degrees, and two pulse signals are generated in the two adjacent positive half-cycle sections of the output voltage of the magnet generator. S
The phase relationship between the output of the signal generator and the output of the magnet generator is set so that 1 and S2 are generated.

If the phase relationship between the output pulse of the signal generator and the output voltage of the magneto generator is set as shown in FIG. 6, the output voltage of the magneto generator will be the same when the engine reverses. Since it is inverted like e1 'shown by the broken line in FIG. 1, the negative pulse signal S1' and the positive pulse signal S2 '
Are generated in the negative half cycle section of the output voltage e1 'of the magneto-generator, and the reverse rotation of the engine can be detected. If it is possible to detect the reverse rotation of the engine in this way, it is possible to misfire the engine by stopping the ignition operation by blocking the application of an ignition signal to the ignition circuit when the reverse rotation is detected, It is possible to prevent the engine from reversing.

However, when the number of poles of the magneto-generator is large, as in the case of using a 12-pole magneto-generator, the angular width of the half-cycle section of the output voltage is very narrow (30 degrees or less). Therefore, it is necessary to put the generation position of each pulse signal within a narrow angle range. Moreover, the phase of the output voltage of the magneto coil of the magneto generator used to charge the battery changes significantly with the load change of the battery and the operation of the voltage regulator. Since the phase relationship between the output voltage of the generator coil and the output pulse of the signal generator changes, the generation position of the two pulse signals output by the signal generator is the output of the magnet generator over the entire rotation speed of the engine. There is a problem that it is extremely difficult to set the voltage so that it enters the interval of two adjacent positive half cycles, and the design of the ignition device becomes difficult.

It is an object of the present invention to use the phase of the output pulse of the signal generator and the output of the magnet generator even when using a magnet generator having 12 or more poles or when it is necessary to increase the advance angle width of the ignition position. It is an object of the present invention to provide a capacitor discharge type internal combustion engine ignition device capable of surely detecting the reverse rotation of the engine based on the phase of (1) and causing the engine to misfire.

[0026]

SUMMARY OF THE INVENTION The present invention is directed to a capacitor discharge type internal combustion engine ignition device in which the ignition position is controlled by a microcomputer. More specifically, the ignition device of the present invention is a multi-pole magnet generator that outputs a multi-phase AC voltage in synchronism with the rotation of an internal combustion engine, and the output of the magnet generator charges a battery through a battery charging circuit. A battery, a DC converter circuit that boosts the output voltage of the battery, an ignition coil, an ignition energy storage capacitor that is provided on the primary side of the ignition coil and is charged with the output voltage of the DC converter circuit, and an ignition signal. A discharge switch that conducts when applied and discharges the charge of the ignition energy storage capacitor to the primary coil of the ignition coil, and discharges the ignition energy storage capacitor to the secondary coil of the ignition coil. An ignition circuit that generates a voltage, a reference position that is set at a position ahead of the top dead center of the internal combustion engine, and a top dead center where the phase is delayed from the reference position. A signal generator that generates the first and second pulse signals at a fixed ignition position that is set at a position more advanced in phase, a rotation speed detection unit that detects the rotation speed of the internal combustion engine, and a rotation speed detection unit. Ignition position calculation means for calculating the ignition position of the internal combustion engine with respect to the rotational speed detected by,
When the rotation speed of the internal combustion engine is equal to or lower than the upper limit value of the low speed region, an ignition signal is given to the discharge switch at the position where the second pulse signal is generated, and when the rotation speed exceeds the upper limit value of the low speed region, the ignition position calculation means. Ignition signal supply means for applying an ignition signal to the discharge switch at the ignition position calculated by

In the present invention, the polarity of the single-phase AC voltage extracted from between the two-phase output terminals of the magnet generator is detected to detect when the single-phase AC voltage is in the positive half cycle and in the negative half cycle. A generator output polarity determination circuit that outputs a polarity determination signal that is different in state at a certain time, and a state of the polarity determination signal when the first pulse signal is generated when the rotation speed of the internal combustion engine is less than or equal to a set value or When the rotation direction determination means determines the rotation direction of the internal combustion engine from the state of the polarity determination signal when the pulse signal of No. 2 is generated, and the rotation direction determination means determines that the rotation direction of the internal combustion engine is the forward direction. A low speed that allows the ignition signal supply means to give an ignition signal to the discharge switch and prohibits the ignition signal supply means from giving an ignition signal to the discharge switch when it is determined that the rotation direction is the reverse direction. Providing an ignition control means. The signal generator is configured to generate the first pulse signal and the second pulse signal in the positive half-cycle section in which the single-phase AC voltage is different when the rotation direction of the internal combustion engine is the positive direction.

As described above, in the present invention, the magnet is used when the first pulse signal or the second pulse signal is generated when the engine is started (when the rotational speed of the engine is below the set value). The direction of rotation of the engine is determined by checking whether the single-phase AC voltage obtained from the generator is in the positive half cycle or in the negative half cycle, and when the reverse rotation of the engine is detected, the ignition circuit Since the ignition signal is prohibited from being given, if the engine is attempted to reverse when the piston is pushed back near the top dead center due to the low rotation speed at the time of starting the engine, the ignition operation will occur. It can be prevented from taking place. Therefore, it is possible to prevent a large force from being applied to the starter device due to the reverse rotation of the engine or the reverse rotation of the engine being maintained.

The set value of the rotation speed of the internal combustion engine may be set equal to, for example, the upper limit value of the low speed region, but generally, the engine may be reversed only at an extremely low speed of the engine, and Since the engine will no longer reverse after a normal start, in order to avoid a situation in which the process of determining the rotation direction is performed when it is unnecessary, the set value of the above rotation speed is set to be higher than the upper limit value of the low speed region. It is preferable to set it low.

The low speed ignition control means prohibits the ignition command signal generating means from generating an ignition command signal when the rotation direction determining means determines that the rotation direction of the internal combustion engine is the opposite direction, and It is preferable that the rotation speed detecting means is also prohibited from detecting the rotation speed.

The generation intervals of the first pulse signal and the second pulse signal output from the signal generator are the angular width of the section of one cycle of the single-phase AC voltage extracted from the two-phase output terminals of the magnet generator ( It is preferable to set it equal to the mechanical angle). For example, when a magnet generator having 12 poles is used, it is preferable that the mechanical interval is 60 degrees between the first pulse signal and the second pulse signal.

The first pulse signal and the second pulse signal are respectively generated at the peak positions of two adjacent positive half cycles of the magneto generator when the rotation speed of the internal combustion engine is less than or equal to a set value. It is preferable to keep it.

In the present invention, when the rotational speed of the engine is less than or equal to the set value, the generation positions of the first pulse signal and the second pulse signal are in the positive half cycle of the single-phase AC voltage obtained from the magnet generator. Since it is not necessary to put the generation positions of the first and second pulse signals in the section of the positive half cycle of the AC voltage in the entire rotation speed region of the engine, it is necessary to enter the section. Phase setting can be facilitated.

Further, since the microcomputer normally recognizes the rising of the pulse signal to the negative or the positive,
The pulse signal and the second pulse signal do not need to be entirely in the positive half cycle section of the AC voltage when the rotation speed is less than or equal to the set value, and at least each rising edge of the AC voltage is The positive half cycle should be entered. Therefore, according to the present invention, as compared with the conventional ignition device that needs to be set so that the entire first and second pulse signals enter the positive half cycle of the AC voltage, The degree of freedom in setting the phase of the output pulse can be increased, and the design and adjustment of the device can be facilitated.

In the present invention, the positive and negative polarities of both half-cycles of the single-phase AC voltage taken out from the magnet generator are relative, and the half-cycle of one polarity of the single-phase AC voltage is positive half-cycle. Then, the half cycle of the other polarity is the negative half cycle. In the present invention, how to determine the polarity of the output of the single-phase AC voltage is arbitrary.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a configuration example of hardware used in one embodiment of the present invention. In FIG. 1, 1 is a magnet that outputs a three-phase AC voltage in synchronization with the rotation of an internal combustion engine. The generator 2 is a full-wave rectifier circuit 2A that rectifies the three-phase AC output generated by the magnet generator 1, and a voltage regulator 2B that controls the output voltage of the rectifier circuit so as to keep it below a predetermined adjustment value.
A battery charging circuit consisting of 3 and 3 is a battery charged by the output of the magnet generator 1 through the battery charging circuit 2, 4 is a DC converter circuit for boosting the output voltage of the battery 3, 5 is a capacitor discharge type ignition circuit, 6 Is a microcomputer. Further, 7 is a signal generator that generates the first and second signals S1 and S2 in synchronization with the rotation of the internal combustion engine, and 8 and 9 are the first and second signals that the signal generator 7 generates.
The first and second waveform shaping circuits for shaping the respective signals S1 and S2 of the above into signal waveforms which can be recognized by the microcomputer, and for supplying the interrupt signals INT1 and INT2 to the input ports A1 and A2 of the microcomputer 6, respectively. Reference numeral 10 is an ignition signal output circuit that gives an ignition signal Si to the ignition circuit 5 when the potential of the output port B of the microcomputer 6 is in a high level state, 11 is a generator output polarity discrimination circuit, and 12 is connected to the battery 3. It is the load of the lamp etc.

The magnet generator 1 includes a magnet rotor 1A in which a permanent magnet is attached to the inner circumference of a peripheral wall portion of a rotor yoke formed in a cup shape to form a 12-pole magnetic field, and a 12-pole stator. Stator 1 with generator coils wound around each salient pole of the iron core
It consists of B and. On the stator side, one with four generator coils that output AC voltage of the same phase connected in series
Three-phase generator coil Lu as a three-phase generator coil
~ Lw is constructed. These three-phase generator coils are star-connected, and the three-phase output terminals 1u, 1v, and 1w are derived from the star-connected generator coils.

The rectifier circuit 2A of the battery charging circuit 2 comprises a known circuit in which diodes Du1, Du2, Dv1, Dv2, Dw1 and Dw2 are connected in a three-phase bridge, and the battery 3 is connected between the DC output terminals of the rectifier circuit 2A. It is connected. The three AC input terminals of the rectifier circuit 2A to which the three output terminals 1u to 1w of the magnet generator are respectively connected and the ground (the battery 3
Thyristors Thu to Thw are respectively connected between the voltage adjusting circuit 2 and
A trigger signal is applied from B1 to the gates of the thyristors Thu to Thw. The voltage adjustment circuit 2B1 detects the DC output voltage obtained between the DC output terminals of the rectifier circuit 2A, and when the DC output voltage exceeds a predetermined adjustment value, the thyristor T
A trigger signal is applied to hu to Thw at the same time. At this time, the thyristor Thu to Thw is electrically connected to the thyristor to which a voltage is applied so that the anode has a positive potential with respect to the cathode, and the conductive thyristor and the diodes Du2, Dv2, and Dw2 on the lower side of the bridge of the rectifier circuit are connected. The output terminals of the magneto generator 1 are short-circuited through either of them. As a result, the output voltage of the magneto generator 1 decreases. When the output voltage of the magneto generator falls below the adjustment value, the supply of the trigger signal to the thyristors Thu to Thw is stopped, so the output voltage of the magneto generator 1 rises. By repeating these operations, the output voltage of the rectifier circuit 2A (the voltage applied to the battery 3) is controlled so as not to exceed the adjustment value, and the output voltage is substantially constant when the engine speed is sufficiently increased. Kept in. In this example, the thyristors Thu to Thw and the voltage adjusting circuit 2B1
And constitute a voltage regulator 2B.

The DC converter circuit 4 has a step-up transformer 4A in which one end of a primary coil is connected to the positive electrode of a battery 3 whose negative electrode is grounded and a primary current is given from the battery.
A switch circuit 4B which is connected in series to the primary coil of the step-up transformer 4A to turn on / off the primary current of the step-up transformer, an oscillator circuit 4C which gives a rectangular-wave drive signal to the switch circuit 4B, and an oscillator coil 4C. It is composed of a diode D1 for half-wave rectifying the output of the secondary coil. In the illustrated example, the emitter is grounded and the collector is connected to the other end of the primary coil of the step-up transformer 4A.
The PN transistor TRo and the resistor Ro connected between the base and emitter of the transistor make the switch circuit 4
B is formed, and a drive signal is applied from the oscillation circuit 4C to the base of the transistor TRo. Step-up transformer 4A
One end of the secondary coil is grounded and the anode of the diode D1 is connected to the other end of the secondary coil.

In the above DC converter circuit 4,
The transistor TRo is turned on / off by the drive signal provided from the oscillator circuit 4C. As a result, the primary current of the step-up transformer 4A is interrupted, so that the boosted voltage is induced in the secondary coil of the step-up transformer 4A, and in the positive half cycle of the induced voltage, the power is supplied to the ignition circuit 5 through the diode D1. Voltage is supplied.

The capacitor discharge type ignition circuit 5 includes an ignition coil IG, an ignition energy storage capacitor Ci provided on the primary side of the ignition coil, and a diode Di connected to both ends of the primary coil of the ignition coil IG. , A thyristor Thi as a discharge switch that conducts when the ignition signal Si is applied to discharge the electric charge of the capacitor Ci through the primary coil of the ignition coil IG, and a resistor Ri connected between the gate and cathode of the thyristor Thi. As is well known, the output voltage of the ignition coil IG is applied to an ignition plug P attached to a cylinder of an engine (not shown). In this ignition circuit, the DC converter circuit 4
→ capacitor Ci → diode Di and ignition coil IG
The primary coil-> DC converter circuit 4 constitutes a capacitor charging circuit, and the output voltage of the DC converter circuit 4 charges the capacitor Ci to the polarity shown in the figure.

When the ignition signal Si is applied to the gate of the thyristor Thi at the ignition position of the internal combustion engine, the thyristor becomes conductive and the charge of the capacitor Ci is discharged through the thyristor Thi and the primary coil of the ignition coil. This induces a high voltage in the secondary coil of the ignition coil. Since this high voltage is applied to the spark plug P, a spark is generated in the spark plug P and the engine is ignited.

The signal generator 7 has a reluctor 7a and is provided so as to rotate in synchronization with the internal combustion engine.
A signal generator 7B which outputs pulse signals S1 and S2 when a magnetic flux is changed by the reluctor of the rotor 7A.
It is composed of In the illustrated example, the magnet generator 1
A reluctor 7a is formed on the outer periphery of the rotor yoke of the above, and the rotor yoke constitutes a rotor 7A of the signal generator. The signal generator 7B is composed of an iron core having a magnetic pole portion facing the rotor 7A and a signal coil 7b wound around the iron core.
And a permanent magnet magnetically coupled to the iron core,
The first pulse signal S1 and the second pulse signal S1 from the signal coil 7b are changed by the change in the magnetic flux generated in the iron core when the reluctor 7a starts to face the magnetic pole portion of the iron core of the signal-generating electron 7B and when the facing ends. Outputs pulse signal S2.

In this example, as shown in FIG. 6A, the reference position (maximum advance position of ignition position or maximum advance position of ignition position) set at a position advanced in phase from the top dead center TDC of the internal combustion engine. At a position slightly advanced in phase) θs1, the first signal S1 is generated, and at a fixed ignition position (position advanced 5 ° to 13 ° from top dead center) suitable as the ignition position during idle rotation, at θs2. Generate a second signal S2. In the example shown,
The first signal S1 and the second signal S2 are composed of a negative pulse signal and a positive pulse signal, respectively, and the first signal S1 and the second signal S2 are respectively formed by the first waveform shaping circuit 8 and It is input to the second waveform shaping circuit 9.

Here, the signal generation position means a position where the signal reaches a predetermined threshold level.

The waveform shaping circuit 8 has its emitter grounded,
An NPN transistor TR1 whose collector is connected to a positive output terminal of a DC power source (not shown) through a resistor R1;
A resistor R2 connected between the base and emitter of the transistor TR1, a diode D3 connected in parallel to both ends of the resistor R2 with the anode facing the ground side, a base of the transistor TR1 and a positive side output of a DC power source (not shown). A resistor R3 connected between the terminal and a transistor TR1
Is composed of a diode D4 having an anode connected to the base of the resistor and a parallel circuit of a resistor R5 and a capacitor C2 having one end connected to the cathode of the diode D4. The other end of the parallel circuit of the resistor R5 and the capacitor C2 is the signal coil 7b. It is connected to the non-grounded side terminal.

In the waveform shaping circuit 9, the emitter is grounded,
NPN transistor TR1 'whose collector is connected to the positive output terminal of the DC power source (not shown) through resistor R1'
A resistor R2 'connected between the base and emitter of the transistor TR1', a diode D4 'whose cathode is connected to the base of the transistor TR1', and a diode D2.
4'is composed of a parallel circuit of a resistor R5 'and a capacitor C2', one end of which is connected to the anode, and the other end of the parallel circuit of the resistor R5 'and the capacitor C2' is connected to the non-grounded side terminal of the signal coil 7b. There is.

A negative first signal S1 is applied to the signal coil 7b.
Occurs, the signal S1 is transferred to the capacitor C2 at the reference position θs1.
When the voltage exceeds a threshold level substantially determined by the residual voltage across the two ends of the current, a current flows from the signal coil 7b through the diodes D3 and D4 and the parallel circuit of the resistor R5 and the capacitor C2, causing a voltage drop across the diode D3. Only while the signal S1 exceeds the threshold level and the voltage drop occurs across the diode D3, the base-emitter of the transistor TR1 is reverse-biased. Will be shut off. When the transistor TR1 is turned off, the potential of the collector of the transistor TR1 changes from a low level (almost ground level) to a high level, so that a pulse waveform signal is obtained at the collector of the transistor TR1. This signal is the external interrupt signal INT
1 is applied to the input port A1 of the microcomputer 6.

A positive second signal S2 is induced in the signal coil 7b, and the residual voltage across the capacitor C2 'is fixed at a fixed ignition position .theta.s2 which is set at a position suitable as an ignition position during idling. When the threshold level, which is substantially determined by the above, exceeds the resistance R from the signal coil 7b.
Parallel circuit of 5'and capacitor C2 'and diode D4
'And the base-emitter of the transistor TR1', a current flows between the transistor TR1 and the base of the transistor TR1 '.
1'becomes conductive. As a result, the transistor TR
A signal having a pulse waveform falling from a high level to a low level is obtained at the collector of 1 ', and this signal is given to the input port A2 of the microcomputer 6 as the external interrupt signal INT2.

The microcomputer 6 includes a CPU 6a,
Interrupt control circuit 6b, random access memory (RA
M) 6c, read only memory (ROM) 6d, counter 6e, comparator 6f, register 6g, latch circuit 6h, edge detection circuit 6i and flip-flop circuit 6j, and waveform shaping circuits 8 and 9 to input port A1 and External interrupt signal IN given through A2
T1 and INT2 are input to the interrupt control circuit 6b. .

The ignition signal output circuit 10 includes an NPN transistor TR2 whose emitter is grounded and the transistor T2.
There is a PNP transistor TR3 whose base is connected to the collector of R2 through a resistor R6. The base of the transistor TR2 is connected to the output port B of the microcomputer through the resistor R7, and the transistor TR2
A resistor R8 is connected between the base and the ground. The emitter of the transistor TR3 is connected to the positive output terminal of a DC power supply circuit (not shown), and the base of the transistor TR3 is connected to the positive terminal of the DC power supply through the resistor R9. The anode of the diode D5 is connected to the collector of the transistor TR3 through the resistor R10, and the cathode of the diode D5 is connected to the gate of the thyristor Thi of the ignition circuit 5.

The generator output polarity discrimination circuit 11 includes an NPN transistor TR4 whose emitter is grounded, a resistor R11 connected between the base and emitter of the transistor TR4,
A resistor R12 connected between the collector of the transistor TR4 and the positive terminal of the DC power source (not shown) and between the base of the transistor TR4 and the positive terminal of the DC power source, respectively.
A diode D6 connected between R13 and R13 and the base-emitter of the transistor TR4 with the cathode facing the base side.
And the anode of the transistor TR4 between the base of the transistor TR4 and the output terminal 1u of the U phase of the magneto generator 1.
Of a transistor TR4 connected to the input port A3 of the microcomputer 6 by a diode D7 connected toward the base side of R2 and a resistor R14 connected between the V-phase output terminal 1v of the magneto-generator 1 and ground. It is connected.

In the generator output polarity discriminating circuit 11 shown in the figure, the output terminals 1u and 1v of the U and V two phases of the magnet generator 1 are shown.
Since the diodes D6 and D7 are reverse-biased when the single-phase AC voltage e1 extracted from between is in the positive half-cycle section and no current flows through both diodes, the transistor TR4 is in a conductive state and the transistor T4 is in a conductive state.
The potential of the collector of R4 (polarity discrimination signal) is almost zero. Therefore, the input port A of the microcomputer 6
The potential of 3 is zero (“0” state). When the single-phase AC voltage e1 extracted from the output terminals 1u, 1v of the U-phase and V2-phase of the magneto generator 1 is in the negative half cycle section, the voltage e1 causes a current to flow through the diodes D6 and D7. A forward voltage drop occurs across diode D6. Due to the forward voltage drop of the diode D6, the base and emitter of the transistor TR4 are reverse-biased, so that the transistor TR4 is turned off. As a result, the potential of the collector of the transistor TR4 (polarity discrimination signal) becomes high level, and the potential of the input port A3 of the microcomputer 6 becomes high level ("1" state).

That is, in this example, when the single-phase AC voltage e1 extracted from the two-phase output terminals of the magnet generator 1 is in a positive half cycle, the polarity determination signal output by the generator output polarity determination circuit 11 is When the single-phase AC voltage e1 is in the negative half cycle, the polarity discrimination signal becomes "1".

In the example shown in FIG. 1, since the magnet generator 1 has 12 poles, its two-phase output terminal 1 is used.
The angular width of each half-cycle section of the single-phase AC voltage e1 extracted from u and 1v is 30 degrees.

In the example shown in FIG. 1, when the polar arc angle of the reluctor 7a of the rotor of the signal generator 7 is set to 60 degrees and the rotation speed of the engine is less than or equal to the set value, the magnet generator of 12 poles The first and second pulse signals S1 and S2 are generated at the peak positions of adjacent positive half cycles of the single-phase AC voltage e1 extracted from the two-phase output terminals 1u and 1v (a predetermined threshold level is reached. ), The signal generator 7 is provided.

In the ignition device shown in FIG. 1, when the external interrupt signal INT1 is given to the interrupt control circuit 6b,
The flip-flop circuit 6j is reset, and the output of the positive logic output terminal Q becomes "0". At this time, if the output of the flip-flop circuit 6j is permitted, the output of the output port B of the microcomputer becomes "0". Further, when the external interrupt signal INT1 is generated, the edge detection circuit 6i detects the rising edge and detects the latch circuit 6h.
To work. The latch circuit 6h receives the interrupt signal INT1
The count value of the counter 6e (the count value of the clock pulse) at the time of occurrence is latched. The interrupt control circuit 6b latches the count value of the counter 6e by the latch circuit 6h and clears the counter 6e. Since the counter is cleared immediately after the count value of the counter 6e is latched, the latched count value corresponds to the time required for the engine to make one revolution. In this embodiment, this count value itself is used as speed data Ne indicating the engine speed Vn. Therefore, the speed data Ne has a larger value as the rotation speed Vn is lower.

A predetermined program and a map used for calculating the ignition position are stored in the ROM 6d of the microcomputer, and the program executes the main routine shown in FIG. 2 and the interrupt routine shown in FIGS. To be executed.

In the illustrated example, the flag 1 is used to identify the rotational direction of the internal combustion engine, and the flag 2 is used to identify whether the rotational speed of the internal combustion engine is in the low speed region.
Further, the flag 3 is used to identify whether or not the ignition signal Si is generated. The flag 1 is set to "1" when it is detected that the engine is rotating normally, and the flag 2 is set when the rotation speed of the internal combustion engine is equal to or lower than the upper limit value of the low speed region (the speed data Ne is equal to or more than the set value N1). Time) is set to "1". Further, the flag 3 is set to "1" when the ignition signal Si is generated.

In the main routine shown in FIG. 2, when the power is established, the flag 1 is set to "0" and the flag 2 is set to "1".
And the maximum value “0FFFFH” of the count value counted by the hexadecimal counter 6e in the RAM that stores the speed data Ne (count value of the counter 6e during one revolution of the engine).
(Indicating that the engine speed is substantially zero) is read. Then, after initializing each part, the ignition position θig at the rotation speed given by the speed data Ne stored in the RAM is calculated,
The process of storing the calculated ignition position θig in the RAM is repeated. The calculation of the ignition position is performed by an interpolation method using a map stored in the ROM 6d, for example. The ignition position calculation means is realized by the process of calculating the ignition position. The ignition position θig is calculated in the form of time (count value of clock pulses) required for the engine to rotate from the reference position θs1 to the ignition position at each rotation speed.

When the interrupt control circuit 6b is supplied with the external interrupt signal INT1 at the reference position θs1, the interrupt processing shown in FIG. 3 is performed. In this interrupt processing, it is first determined whether or not the flag 1 is "1". When it is determined that the flag 1 is “1” (when the engine is rotating normally), the counters latched by the latch circuit 6h are reset after resetting the flags 1 and 3 to “0”. Of the count value (the number of clock pulses counted by the counter during one revolution of the engine) of the speed data N
It is stored in the RAM 6c as e. Through this process, the rotation speed detecting means is realized.

Next, the speed data Ne is set to the first set value N.
Determine if it is less than 1. Here, the first set value N
1 is the upper limit Vn1 in the extremely low speed region (idling region) of the engine
(For example, 2000 rpm). As a result of comparing the speed data Ne with the set value N1, when Ne ≧ N1 (when the rotation speed is equal to or lower than the upper limit value Vn1 in the low speed region)
The output of the flip-flop circuit 6j is output port B
After prohibiting the output from, the flag 2 is set to "1" and the process returns to the main routine. As a result of comparing the speed data Ne with the set value N1, when Ne <N1 (when the rotation speed exceeds the upper limit value Vn1 in the low speed region), the output of the flip-flop circuit 6j is output from the output port B. Flag 2 is set to "0" after permitting the operation, the calculated ignition position θig is transferred to the register 6g, and then the process returns to the main routine.

The signal coil 7b moves to the second position at the fixed ignition position θs2.
When the interrupt signal INT2 is given to the microcomputer by generating the signal S2 of FIG. 4, the interrupt routine of FIG. 4 is executed. In this interrupt routine, it is first determined whether the speed data Ne is smaller than the second set value N2. Here, the second set value N2 gives a set value Vn2 (for example, 1000 rpm) in the speed range for determining the rotation direction, and the second set value N2 is set to a value larger than the first set value N1. To be done. When Ne ≧ N2 is satisfied as a result of comparing Ne and N2 (when the rotation speed is equal to or lower than the set value Vn2), the input signal level of the port A3 of the microcomputer is checked and the input signal level of the port A3 is " In the case of "0" (when the single-phase AC voltage e1 extracted from the magneto generator when the second signal S2 is generated is in the positive half cycle), then whether the flag 1 is "0" or not If the result is that the flag 1 is "0", the flag 1 is set to "1" (a state indicating that the engine is rotating normally). Then, it is determined whether or not the flag 2 is "1". When the flag 2 is "1" (when the rotation speed is in the low speed region), the output signal level of the output port B of the microcomputer is set to "1". 1 ”(high level condition)
After that, a value obtained by adding the numerical value α corresponding to the signal width of the ignition signal to the count value of the counter 6e at that time is put in the register 6g. After that, the flag 3 is set to "1" (a state indicating that the ignition signal Si is generated) and the process returns to the main routine.

When it is determined that the signal level of the port A3 is "1" when the second pulse signal S2 is generated (when it is determined that the engine is reversing), do nothing. Return to the main routine.

When the signal level of the port A3 is "0", it is determined that the flag 1 is already "1", and when the flag 2 is determined to be "0" ( When it is determined that the engine rotation speed Vn exceeds the upper limit value Vn1 in the low speed region), nothing is done and the process returns to the main routine.

When the output of the port B is set to "1" in the interrupt routine of FIG. 4, a base current flows through the transistor TR2 of the ignition signal output circuit 10 and the transistor T2 is turned on.
Since R2 is turned on, the transistor TR3 is turned on, and the ignition signal Si is applied to the thyristor Thi from the DC power supply circuit (not shown) through the transistor TR3, the resistor R10 and the diode D5. Thyristor Thi
When the counter 6e counts the count value corresponding to α after the ignition signal is given to the counter, the count value of the counter coincides with the content of the register 6g. Therefore, the comparator 6f gives the set signal to the flip-flop circuit 6j. The output Q of the flip-flop circuit is set to "1" and the interrupt signal INT3 is supplied to the interrupt control circuit 6b. Ne ≧ N
When it is 1 (when the rotation speed is in the low speed region), the output of the flip-flop circuit is prohibited, so the change in the output when the flip-flop circuit is set affects the output of the output port B. Do not give.

The interrupt control circuit 6b receives the interrupt signal INT.
When 3 occurs, the interrupt routine shown in FIG. 5 is executed. When Ne ≧ N1 (low speed region of the engine), when the count value of the counter 6e becomes equal to the count value set in the register 6g in the interrupt routine of FIG. 4 (the second signal S2 is generated). When the time corresponding to the rear signal width α has elapsed), the interrupt signal INT3 is generated and the interrupt routine of FIG. 5 is executed. In the interrupt routine shown in FIG. 5, first, it is determined whether the flag 3 is "0". When Ne ≧ N1 (when the rotation speed is in the low speed region), the flag 3 is set to "1" in the interrupt routine of FIG. 4, so that the output of the port B is set to "0" and the transistor TR2 and After turning off TR3 (after extinguishing the ignition signal), the process returns to the main routine.

When Ne <N1 (when the engine speed exceeds the upper limit value Vn1 in the low speed region), the count value of the counter 6e is set to the ignition position set in the register 6g in the interrupt routine of FIG. When the count value of θig matches, the interrupt signal INT3 is generated and the interrupt routine of FIG. 5 is executed. At this time, the flag 3 is "0" [the flag 3 is not set to "1" in the interrupt routine of FIG. 4 because Ne <N1 (<N2)].
A value obtained by adding α (signal width) to the current count value of the counter is transferred to the register 6g, the flag 3 is set to “1”, and the process returns to the main routine. After that, when the count value corresponding to the signal width α of the ignition signal is counted and the interrupt signal INT3 is generated, the interrupt routine of FIG. 5 is executed again. Since the flag 3 is "1" at this time, the output of the port B of the microcomputer is forcibly set to "0" and the process returns to the main routine.

In the above example, the rotation speed detecting means is realized by the process of latching the count value of the counter and fetching the latched count value in the interrupt routine of FIG.
The ignition position calculating means is realized by the process of calculating the ignition position θig of the main routine.

In the interrupt routine of FIG. 3, the rotational speed detected by the rotational speed detecting means is determined by the process of determining the magnitude relationship between the speed data Ne and the first set value N1 that gives the upper limit value Vn1 of the low speed region. A speed region determination unit that determines whether or not the speed region is equal to or less than the upper limit value of the low speed region is realized.

Further, in the interruption routine of FIG. 3, the process of permitting the output of the flip-flop circuit and transferring θig to the register, and the interruption routine of FIG. A steady operation time point ignition command signal generating means for generating an ignition command signal at the ignition position calculated by the ignition position calculating means when it is determined that the upper limit value Vn1 is exceeded is realized.

In the interrupt routine of FIG. 4, Ne
By the process of determining the magnitude relationship between the engine speed and N2, the engine speed determining means for determining whether the engine speed Vn exceeds a set value set lower than the upper limit value Vn1 in the low speed region is realized.

Further, in the interrupt routine of FIG. 4, in the process of determining whether or not the signal level of the port A3 is "0", the polarity determination signal from the state when the second pulse signal S2 is generated is changed to the internal combustion engine. A rotation direction determination means for determining the rotation direction of the engine is realized.

Further, in the interrupt routine of FIG. 4, it is judged whether or not the flag 1 is "0", and it is prohibited to give the ignition signal to the discharge switch at the fixed ignition position according to the judgment result. When the rotation direction of the internal combustion engine is determined to be the forward direction by the process of allowing and allowing, the ignition signal supply means allows the ignition signal to be supplied to the discharge switch, and the rotation direction is the reverse direction. When it is determined that the ignition signal supply means prohibits the ignition signal from being supplied to the discharge switch, the low-speed ignition control means is realized.

As described above, in the illustrated example, when the engine speed is equal to or lower than the set value Vn2 set lower than the upper limit value Vn1 in the low speed region (at an extremely low speed), the rotation direction of the internal combustion engine is changed. When the reverse rotation of the engine is detected, it is prohibited to give an ignition signal to the discharge switch (thyristor Thi in the illustrated example) of the ignition circuit 5, and the rotation speed detection means detects the rotation speed. Prohibit detection. When it is determined that the engine is rotating normally at extremely low engine speeds, and when the engine speed exceeds the set value, the engine speed is detected and an ignition signal is given to the discharge switch. Tolerate.

With this structure, the ignition operation is prevented when the engine is about to reverse because the piston is pushed back near the top dead center due to the low rotation speed at the time of starting the engine. can do. Therefore, it is possible to prevent a large force from being applied to the starter device due to the reverse rotation of the engine or the reverse rotation of the engine being maintained.

Further, according to the above configuration, when the rotational speed Vn of the engine is less than or equal to the set value Vn2, the generation positions of the first pulse signal and the second pulse signal are the single-phase AC voltage obtained from the magnet generator. It suffices to enter the section of the positive half cycle of, and it is not necessary to put the generation positions of the first and second pulse signals in the section of the positive half cycle of the AC voltage in the entire rotational speed region of the engine. It is possible to easily set the phase of the output of the signal generator.

Further, as shown in FIG. 1, the microcomputer 6 receives the first and second pulse signals S1 and S2 through the waveform shaping circuits 8 and 9 as an input, and raises these pulse signals to the negative or positive. Is recognized as a signal, the first pulse signal S1 and the second pulse signal S
2 does not need to be entirely in the positive half cycle of the AC voltage, but at least each rising edge is in the positive half cycle of the AC voltage. Therefore, according to the present invention, it is only necessary to set the first and second pulse signals so as to enter the positive half cycle section of the AC voltage only when the rotation speed is equal to or lower than the set value. Therefore, the degree of freedom in setting the phase of the output pulse of the signal generator can be increased, and the design and adjustment of the device can be facilitated.

In the above example, the set value Vn2 of the rotation speed that gives the upper limit of the speed range for determining the engine rotation direction is set lower than the upper limit value of the low speed range. The rotational speed setting value Vn2 that gives the upper limit of the speed range to be performed may be made equal to the upper limit value Vn1 of the low speed range.

In the above example, it is determined whether the single-phase AC voltage e1 extracted from the magneto generator when the second pulse signal S2 is generated at the fixed ignition position is in the positive half cycle or the negative half cycle. The rotation direction of the engine is determined by determining whether the single-phase AC voltage e1 is in the positive half cycle or the negative half cycle when the first pulse signal S1 is generated. The direction of rotation of the engine may be determined by looking.

As in the above example, not only is the ignition direction signal generation means prohibited from generating the ignition direction signal when the rotation direction determination means determines that the rotation direction of the internal combustion engine is the reverse direction, If the low-speed ignition control means is configured so that the rotation speed detection means also prohibits the detection of the rotation speed, the speed data Ne will be output regardless of the rotation speed of the engine when reverse rotation occurs. Maximum value "0FFFF
H ”(rotational speed is substantially zero), so that when the engine reverses, it is forcibly rotated by external force and its rotational speed Vn exceeds the set value Vn2. Even if occurs, the speed data Ne is Ne ≧ N2
Therefore, the engine can be kept in the misfire state, and the reversal of the engine can be prevented from continuing. However, when the engine reverses, its rotation speed is set to a set value (for example, 10
It is not always necessary to configure as in the above example, because it is unlikely that a state exceeding 100 rpm) usually occurs, and it is prohibited to generate an ignition signal only when reverse rotation of the engine is detected. However, the rotation speed may be detected.

In the above example, a 12-pole magnet generator is used, but it is needless to say that the present invention can be applied to a case where a magnet generator having more poles than 12 poles is used. When using a multi-pole magnet generator with less than 12 poles, for example,
Even when an 8-pole magnet generator is used, the polar arc angle of the reluctor of the signal generator is set to be larger than the angle width of the half-cycle section of the output voltage of the magnet generator in order to make the advance width wider. The present invention is useful when it is necessary to make the output voltage wider than the angular width of the half cycle section.

In the above example, the first pulse signal S1 is a negative pulse signal and the second pulse signal S2 is a positive pulse signal, but the polarities of these pulse signals may be reversed. .

[0084]

As described above, according to the present invention, the rotation direction of the engine is detected when the rotation speed of the engine is less than the set value, and the ignition signal is sent to the ignition circuit when the reverse rotation of the engine is detected. Since it is prohibited to give the ignition, it is possible to prevent the ignition operation from being performed at the time of reverse rotation of the engine, a large reaction force acts on the starting device of the engine, or the reverse rotation of the engine is maintained. Can be prevented.

Further, in the present invention, the direction of rotation is determined only when the engine speed is equal to or lower than the set value. Therefore, the pulse signal generated by the signal generator is generated by the magnet only when the engine speed is extremely low. The positive half cycle of the single-phase AC voltage obtained from the machine may be entered, and the generation positions of the first and second pulse signals in the entire rotation speed region of the engine are set to the positive half cycle of the AC voltage. The phase setting of the output of the signal generator can be facilitated as compared with the conventional ignition device that has to be inserted in the section.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration example of hardware used in an embodiment of the present invention.

2 is a flowchart showing an algorithm of a main routine of a program executed by a microcomputer in the embodiment of FIG.

3 is a flowchart showing an algorithm of an interrupt routine of a program executed by a microcomputer in the embodiment of FIG.

FIG. 4 is a flowchart showing an algorithm of another interrupt routine of a program executed by the microcomputer in the embodiment of FIG.

5 is a flowchart showing an algorithm of still another interrupt routine of the program executed by the microcomputer in the embodiment of FIG. 1. FIG.

FIG. 6 is a waveform diagram showing a single-phase AC voltage extracted from the magnet generator and a pulse signal generated by the signal generator.

[Explanation of symbols]

 1 Magnet Generator 2 Battery Charging Circuit 3 Battery 4 DC Converter Circuit 5 Ignition Circuit 6 Microcomputer 7 Signal Generator 8 Waveform Shaping Circuit 9 Waveform Shaping Circuit 10 Ignition Signal Supply Circuit 11 Generator Output Polarity Discrimination Circuit 12 Load

Claims (3)

[Claims] 1. A multi-pole magnet generator that outputs a multi-phase AC voltage in synchronism with the rotation of an internal combustion engine, a battery charged by a battery charging circuit with the output of the magnet generator, and an output voltage of the battery. A DC converter circuit for boosting the voltage, an ignition coil, an ignition energy storage capacitor which is provided on the primary side of the ignition coil and is charged with the output voltage of the DC converter circuit, and which conducts when an ignition signal is applied. An ignition circuit that includes a discharge switch that discharges the electric charge of the ignition energy storage capacitor to the primary coil of the ignition coil, and generates a high voltage for ignition in the secondary coil of the ignition coil by discharging the ignition energy storage capacitor, A reference position set at a position ahead of the top dead center of the internal combustion engine and a phase behind the reference position and a phase ahead of the top dead center. A signal generator for generating the first and second pulse signals at the fixed ignition position set to the position, and a rotation speed detecting means for detecting the rotation speed of the internal combustion engine from the generation cycle of the output pulse of the signal generator. An ignition position calculation means for calculating an ignition position of the internal combustion engine with respect to the rotation speed detected by the rotation speed detection means; and the second position when the rotation speed of the internal combustion engine is equal to or lower than an upper limit value of a low speed region.
An ignition signal is given to the discharge switch at the position where the pulse signal is generated, and when the rotation speed exceeds the upper limit value of the low speed region, the ignition signal is given to the discharge switch at the ignition position calculated by the ignition position calculation means. In the ignition device for a capacitor discharge type internal combustion engine, which is provided with an ignition signal supply means for providing a single-phase AC voltage, the polarity of the single-phase AC voltage extracted from the two-phase output terminals of the magneto-generator is detected. A generator output polarity discriminating circuit that outputs a polarity discriminating signal that is different in the positive half cycle and the negative half cycle, and determines whether the internal combustion engine rotation speed exceeds the set value. Rotation speed determining means, and the polarity when the first pulse signal is generated when the rotation speed determining means determines that the rotation speed of the internal combustion engine is less than or equal to a set value. A rotation direction determination unit that determines the rotation direction of the internal combustion engine from the state of the separate signal or the state of the polarity determination signal when the second pulse signal is generated, and the rotation direction determination unit determines that the rotation direction of the internal combustion engine is the positive direction. When it is determined that the ignition signal supply means to give an ignition signal to the discharge switch, when the rotation direction is determined to be the reverse direction, the ignition signal supply means to the discharge switch. Low-speed ignition control means for prohibiting application of an ignition signal, wherein the first pulse signal and the second pulse signal are positive when the single-phase AC voltage is different when the rotation direction of the internal combustion engine is a positive direction. The signal discharger is configured so as to be generated in a half cycle of the above. 2. A multi-pole magnet generator that outputs a multi-phase AC voltage in synchronism with the rotation of an internal combustion engine, a battery charged by a battery charging circuit with the output of the magnet generator, and an output voltage of the battery. A DC converter circuit for boosting the voltage, an ignition coil, an ignition energy storage capacitor which is provided on the primary side of the ignition coil and is charged with the output voltage of the DC converter circuit, and which conducts when an ignition signal is applied. An ignition circuit that includes a discharge switch that discharges the electric charge of the ignition energy storage capacitor to the primary coil of the ignition coil, and generates a high voltage for ignition in the secondary coil of the ignition coil by discharging the ignition energy storage capacitor, A reference position set at a position ahead of the top dead center of the internal combustion engine and a phase behind the reference position and a phase ahead of the top dead center. A signal generator for generating the first and second pulse signals at the fixed ignition position set to the position, and a rotation speed detecting means for detecting the rotation speed of the internal combustion engine from the generation cycle of the output pulse of the signal generator. An ignition position calculation means for calculating an ignition position of the internal combustion engine with respect to the rotation speed detected by the rotation speed detection means; and the second pulse when the rotation speed of the internal combustion engine is equal to or lower than an upper limit value of a low speed region. An ignition signal is given to the discharge switch at the signal generation position, and an ignition signal is given to the discharge switch at the ignition position calculated by the ignition position calculation means when the rotation speed exceeds the upper limit of the low speed region. In a capacitor discharge type internal combustion engine ignition device including an ignition signal supply means, the polarity of a single-phase AC voltage extracted from between the two-phase output terminals of the magneto-generator is determined. Separately, a generator output polarity determination circuit that outputs a polarity determination signal whose state is different when the single-phase AC voltage is in the positive half cycle and in the negative half cycle, and the rotation speed of the internal combustion engine in the low speed region Rotation speed determination means for determining whether or not it is greater than or equal to a set value set lower than the upper limit value, when the rotation speed of the internal combustion engine is determined to be less than the set value by the rotation speed determination means, A rotation direction for determining whether the rotation direction of the internal combustion engine is the forward direction or the reverse direction from the state of the polarity determination signal when the first pulse signal is generated or the state of the polarity determination signal when the second pulse signal is generated. The rotation speed detection means prohibits the rotation speed from being detected when the rotation direction determination means determines that the rotation direction of the internal combustion engine is the opposite direction, and the ignition command signal is detected. The generation means prohibits the generation of the ignition command signal, and the rotation speed is detected when the rotation speed is equal to or higher than a set value and when the rotation direction determination means determines that the rotation direction of the internal combustion engine is the forward direction. Means for detecting a rotation speed and allowing the ignition command signal generating means to generate an ignition command signal. The signal generator is configured such that the first pulse signal and the second pulse signal are generated in positive half-cycle intervals of the single-phase AC voltage different from each other. Ignition device. 3. A 12-pole magnet generator that outputs three-phase AC voltage in synchronism with rotation of an internal combustion engine by connecting three-phase generator coils, and a three-phase AC output of the magnet generator through a battery charging circuit. A battery to be charged, a DC converter circuit for boosting the output voltage of the battery, an ignition coil, an ignition energy storage capacitor provided on the primary side of the ignition coil and charged with the output voltage of the DC converter circuit, and ignition. A secondary switch of the ignition coil is ignited by discharge of the ignition energy storage capacitor by providing a discharge switch that conducts when a signal is given to discharge the electric charge of the ignition energy storage capacitor to the primary coil of the ignition coil. Ignition circuit that generates a high voltage for the internal combustion engine, a reference position set at a position ahead of the top dead center of the internal combustion engine, and the reference position The phase is delayed and the phase is advanced from the top dead center, the fixed ignition position is set to the first position.
And a signal generator that generates a second pulse signal, a rotation speed detection unit that detects the rotation speed of the internal combustion engine from the generation cycle of the output pulse of the signal generator, and a rotation speed that is detected by the rotation speed detection unit. And an ignition position calculation means for calculating the ignition position of the internal combustion engine, and an ignition signal to the discharge switch at the generation position of the second pulse signal when the rotation speed of the internal combustion engine is equal to or lower than the upper limit value of the low speed region. And an ignition signal supply means for giving an ignition signal to the discharge switch at the ignition position calculated by the ignition position calculation means when the rotation speed exceeds the upper limit of the low speed region. In the engine ignition device, the polarity of the single-phase AC voltage extracted from the two-phase output terminals of the three-phase output terminals of the magnet generator is discriminated to determine that the single-phase AC voltage is positive. The generator output polarity discriminating circuit that outputs the polarity discriminating signal whose state is different depending on whether it is in the half cycle or in the negative half cycle, and the rotation speed of the internal combustion engine is set lower than the upper limit value of the low speed region. Rotation speed determining means for determining whether or not the rotation speed of the internal combustion engine is less than or equal to a set value, and the first pulse signal is generated when the rotation speed determination means determines that the rotation speed of the internal combustion engine is less than a set value. And a rotation direction determination means for determining whether the rotation direction of the internal combustion engine is the forward direction or the reverse direction from the state of the polarity determination signal at the time or the state of the polarity determination signal when the second pulse signal is generated. The rotation speed detecting means prohibits the rotation speed from being detected when the rotation direction of the internal combustion engine is determined to be the reverse direction by the means, and the ignition command signal generating means causes the ignition command signal generating means to detect the rotation speed. The rotation speed detection means detects the rotation speed when the rotation speed is equal to or higher than a set value and when the rotation direction determination means determines that the rotation direction of the internal combustion engine is the forward direction. And a low-speed time point ignition control means for permitting the ignition command signal generating means to generate an ignition command signal, and the generation interval of the first pulse signal and the second pulse signal is mechanical. The first pulse signal and the second pulse signal are generated in different positive half-cycle intervals of the single-phase AC voltage when the angle is 60 degrees and the rotation direction of the internal combustion engine is the positive direction. An ignition device for a capacitor discharge type internal combustion engine, comprising a signal generator.