JPH0333916B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a capacitor discharge type non-contact ignition device for an internal combustion engine.

Conventionally, in order to make the capacitor's charging voltage almost uniform from low to high engine speeds, this type of capacitor's charging source used a thin wire with a large number of turns to charge the capacitor mainly at low speeds during low-speed rotation. It consisted of a coil and a high-speed coil with a large wire diameter and a small number of turns that charged the capacitor mainly during high-speed rotation, and the capacitor was directly charged by the output of these two coils.

However, the above-mentioned conventional system (1) requires two coils as the capacitor charging coil, one for low speed and one for high speed, which have different specifications, resulting in a complicated structure. Moreover, the dimensions become larger and the size of the magnet generator becomes larger.

(2) The low-speed charging coil is a thin wire (wire diameter 0.13 to 0.16
mm) is wound a lot (3000 to 7000 turns),
Workability is poor and quality problems are likely to occur.

(3) If an attempt is made to increase the secondary voltage, ie, the capacitor voltage, at low speeds, the secondary voltage, ie, the capacitor voltage at medium and high speeds will increase, and the heat resistance of the ignition coil or semiconductor element will be insufficient. There are other problems.

In order to solve the above-mentioned problems, the present invention substantially short-circuits one half-wave output of the generating coil by a short-circuiting semiconductor switching element connected in parallel with the capacitor, and when this semiconductor switching element shuts off, By charging the capacitor with the high voltage induced in the generator coil and supplying the other half-wave output of the generator coil to other loads through the diode, it is possible to use the generator coil with a thick wire diameter and a small number of turns. Therefore, it is an object of the present invention to provide a non-contact ignition device for an internal combustion engine that can satisfactorily charge a capacitor and supply power to other loads while suppressing heat generation in each element.

The present invention will be described below with reference to embodiments shown in the drawings.

First, in the first embodiment shown in FIG.
1.0, the number of turns is 200 to 600 times, and in a magnet generator of the same size, the wire diameter is about 4 times thicker than that of a conventional capacitor charging coil, and the number of turns is about 1/10. 2 is a timing sensor that generates an output signal at a reference position; 3a and 3b are diodes for extracting a reverse half-wave output from the charging coil 1 indicated by the broken line arrow; and 4, Reference numeral 5 denotes voltage dividing resistors connected in series between the terminals of the generating coil 1 via a diode 11a, and the voltage dividing point a thereof is connected to the gate of the thyristor 6. This thyristor 6 is connected between the base and emitter of a transistor 8. Reference numeral 7 denotes a base resistor of the transistor 8, and this resistor 7, the thyristor 6, and the resistors 4 and 5 constitute a cut-off control circuit. Further, the transistor 8 serves as a short-circuiting semiconductor switching element that short-circuits the forward output of the coil 1. 9 and 10 are voltage dividing resistors connected in series between the terminals of the thyristor 11 via a diode 9a;
The voltage dividing point b is connected to the gate of the thyristor 11, and when the voltage generated in the coil 1 after the transistor 8 is turned off exceeds a set value, the thyristor 11 is made conductive. And power generation coil 1
Thyristor 1 outputs the positive half-wave output shown by the solid arrow.
1 and the battery 20 via the diode 11a.
It is designed to be supplied to This thyristor 11, resistors 9 and 10, and diode 9a,
11a constitutes a high voltage responsive half wave extraction circuit. 12 is a discharge blocking diode, 13 is an ignition capacitor, and 14 uses the positive output of the generating coil 1 as a power source, and uses the output signal of the timing sensor 2 as input to electronically determine the ignition timing and generate an ignition signal. This is a known electronic ignition signal generation circuit. 15 is a DC arc diode, 16 is an ignition coil, 16a is its primary coil, and 16b is its secondary coil. Reference numeral 17 denotes an ignition plug, and 18 an ignition thyristor serving as a semiconductor switching element for ignition.When an ignition signal from the ignition signal generation circuit 14 is applied to the gate, the thyristor becomes conductive and transfers the charge in the capacitor 13 to the ignition coil 16. It is supplied to the primary coil 16a. 19 is a resistance. Reference numeral 22 is a known regulator that short-circuits the negative output of the power generating coil 1, indicated by a broken line arrow, when it exceeds a predetermined value.

Next, the magnet generator used in this example includes a rotor magnetized with 12 poles of N and S alternately magnetized at equal intervals, and a ring-shaped stator core with 12 protrusions formed at equal intervals on the outer periphery. The generating coil 1 is wound around the two protrusions of the stator core and connected in series with each other, and as the rotor rotates, the generating coil 1 is connected to the rotor 1 of the magnet generator as shown in FIG. 2a. Six cycles of non-negative AC voltage are generated per rotation.

Now, when a half-wave output starts to be generated in the generator coil 1 in the direction of the solid arrow in Fig. 1 (positive direction), the coil 1→
Resistor 7 → Base/emitter of transistor 8 → Ground → Transistor 8 in the circuit of diode 11a
A base current flows through the transistor 8, conduction occurs between the collector and emitter of the transistor 8, and the positive half-wave output of the coil 1 is short-circuited. At this time, as the short-circuit current of transistor 8 increases as shown in FIG. do. When this voltage reaches a set value (for example, a voltage value corresponding to a short circuit current of 0.5 to 4 A), thyristor 6 becomes conductive and short-circuits between the base and emitter of transistor 8.
The circuit between the collector and emitter of is turned OFF, and the short circuit current is abruptly cut off. At this time, a large induced voltage is generated in the coil 1 as shown in Fig. 2c, and this high voltage causes the capacitor 13 to be
The circuit from ground to diode 11a fully charges the battery as shown in Figure 2d. Also, when the induced voltage exceeds the set value (for example, 100 to 300V), the resistor 9,
The voltage at the connection point b of the voltage dividing circuit 10 increases, and the thyristor 11 becomes conductive. As a result, the positive half-wave output of the coil 1 is supplied to the battery 20 via the thyristor 11 and the diode 11a, and the battery 20 is charged with the current shown in FIG. 2f. By charging the battery 20 in this way, the positive half-wave output of the coil 1 is suppressed,
Prevent overvoltage to each element. On the other hand, the reverse half-wave output of the coil 1 (indicated by the broken line arrow in FIG. 1) is supplied to the battery 20 via the diodes 3a and 3b, and charges the battery 20 with the current shown in FIG. 2g. By charging the battery 20 in this way, the reverse half-wave output of the coil 1 is suppressed to prevent excessive reverse voltage from being applied to the thyristors 6, 11 and the transistor 8, and a reverse current is caused to flow through the coil 1. In particular, the armature reaction suppresses the magnitude of the subsequent positive output and reduces the current in the coil 1 (FIG. 2b) and the current in the thyristor 6. This prevents heat generation in the coil 1 and prevents the thyristor 6, resistor 4,
It can be downsized by 5.7.

Furthermore, when the ignition timing is reached, the ignition signal generation circuit 1 receives the output from the timing sensor 2 shown in FIG.
4, the thyristor 18 becomes conductive, and the charge in the capacitor 13 is rapidly discharged in the circuit of the capacitor 13 → thyristor 18 → ground → the primary coil 16a of the ignition coil 16, and the ignition coil A high voltage is applied to the 16 secondary coil 16b, and an ignition spark is generated at the ignition plug 17.

Here, the ignition signal generated in the ignition signal generation circuit 14 is generated when the half-wave output not supplied to the ignition power source is generated in the generator coil 1 as indicated by the broken line arrow in FIG. is preferred. This is because when the thyristor 18 is turned on by the ignition signal while the coil 1 is generating a half-wave output in the direction of the solid arrow, this half-wave output is short-circuited by the thyristor 18, and the battery charging current is reduced accordingly. This is to prevent this.

FIG. 3 shows the battery voltage and battery charging current characteristics with respect to the engine speed in the first embodiment, where characteristic A is the battery voltage and characteristic B is the case where the output of coil 1 is used only for battery charging. Characteristic C shows the battery charging current in the circuit shown in Figure 1 in which the output of coil 1 is used for both battery charging and ignition power supply, Even if the coil 1 is used for both purposes, a battery charging current almost the same as that obtained when the output of the coil 1 is used only for battery charging can be obtained.

FIG. 4 shows a second embodiment of the present invention.
Generating coils 1a, 1b, 1 with a phase difference of 120°
Each of these coils 1a,
1b and 1c are connected in a three-phase Y type, and a diode 3a is connected.
It is connected to a battery 20 through a three-phase full-wave rectifier composed of ~3d, 11a and a thyristor 11, and a part of the half-wave output of one phase of the rectifier is used as an ignition power source. In this FIG. 4, the cathode of the thyristor 11 is connected to the battery 20.
Instead of connecting to the lamp 23 as shown by the dashed line
Alternatively, the lamp 23 may be turned on by connecting the lamp 23 to the lamp 23.

FIG. 5 shows a third embodiment of the present invention, in which, in contrast to the second embodiment, the battery charging side half-wave outputs of the generator coils 1a to 1c are converted into voltage by a regulator 22a of a known single-phase full-wave short-circuit system. The single-phase full-wave rectifier 3 combined with the regulator 22a is used to charge the battery 20 with the outputs of the coils 1a to 1c. According to this embodiment, the circuit can be constructed using a single-phase full-wave short-circuit regulator 30 with a full-wave rectifier that is currently commercially available. Here, the cathode of the thyristor 11 may be connected to the anode side of the diode 3c.

FIG. 6 shows a fourth embodiment of the present invention. In contrast to the first embodiment, the conduction control timing of the thyristor 11 at low speed is set so that the induced voltage in the coil 1 after the transistor 8 is cut off reaches the peak point. The induced voltage of coil 1 causes diode 12 to
The charge of the capacitor 33 charged through the resistor 32 and the diode 31 is supplied to the gate of the thyristor 11 through the diode 31 and the programmable union transistor 34. According to this embodiment, even during low speed rotation when the induced voltage of the coil 1 when the transistor 8 is cut off is lower than the set value, the battery 20 is charged by the induced voltage after the capacitor of the coil 1 is charged when the transistor 8 is cut off. can do. Here, resistor 9 and diode 9a
may be omitted and the thyristor 11 may be made conductive immediately after the induced voltage in the coil 1 after the transistor 8 is cut off exceeds the peak point even when the rotational speed becomes high. FIG. 7 shows a fifth embodiment of the present invention. In contrast to the second embodiment, two power generating coils 1a and 1b that generate outputs in the same phase are used, and each terminal is connected to a three-phase full-wave rectifier. It was designed to connect to. In this way, the diameter and number of turns of the coil 1a can be arbitrarily set according to the charging of the battery 20, and the coil wire diameter and the number of turns can be arbitrarily set according to the ignition power source of the coil 1b.

FIG. 8 shows a sixth embodiment of the present invention, which differs from the first embodiment in that the output of the coil 1 is supplied to the lamp 40 instead of the battery 20,
Further, an ignition signal generating circuit 14a is used which supplies the negative direction output of the coil 1 to the gate of the thyristor 18 via a resistor 51 and a diode 52 as an ignition signal. In FIG. 8, reference numeral 41 is an operation switch that turns on and off the lamp 40, and 42 is a resistor that is connected to the coil 1 when the lamp 40 is turned off.

In each of the embodiments described above, the high voltage responsive half-wave extraction circuit including the resistors 9 and 10 and the thyristor 11 may be omitted in some cases.

Further, in each of the embodiments described above, an electronic ignition signal generation circuit 14 that uses the output signal of the timing sensor 2 as input to electronically determine the ignition timing, or an ignition signal generation circuit that uses the negative direction output of the coil 1 as an ignition signal. 14a, an ignition signal generating circuit which directly applies the output signal of the timing sensor 2 as a control signal to the thyristor 18 may be used.

As described above, in the present invention, when a short circuit current due to the half-wave output on the capacitor charging side of the generating coil is sufficiently flowing through the short-circuiting semiconductor switching element that substantially short-circuits one half-wave output of the generating coil, and a cut-off control circuit for cutting off the short-circuiting semiconductor switching element, the capacitor is charged by the high voltage induced in the generating coil when the short-circuiting semiconductor switching element is cut off, and the other half wave of the generating coil is charged. Since the output is supplied to other loads through the reverse half-wave extraction diode,
It has excellent effects as described below.

(1) Conventionally, a capacitor charging coil required two coils with different specifications: a thin wire coil with a large number of turns and a thick wire coil with a small number of turns, but it is now possible to use only a thick wire coil with a small number of turns. The structure is simple and the body size can be reduced.

(2) There is a large degree of freedom in setting the capacitor voltage and secondary voltage, sufficient ignition performance can be obtained from low speeds, and starting performance can be improved.

(3) Since there is no need to use thin wire as a capacitor charging coil, quality problems can be resolved.

(4) When the reverse half-wave output diode supplies the other half-wave output of the generator coil to other loads, the armature reaction suppresses the half-wave output of one of the generator coils, reducing the current flowing through each element. As a result, power can be effectively supplied to other loads while suppressing the heat generation of each of these elements.

Furthermore, in the present invention, the voltage induced in the generator coil is detected when the short-circuit semiconductor switching element is cut off, and each time this voltage exceeds a set value, the half-wave output of one of the generator coils is transferred to the other load. Since the power is continuously supplied, it is possible to suppress the induced voltage in the generator coil to the set value, and then supply the continuously generated unnecessary voltage to other loads, thereby effectively supplying power to other loads. In addition, the heat generation of each element can be further suppressed, and the heat generation of the power generation coil can also be suppressed.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit diagram showing a first embodiment of the device of the present invention, Fig. 2 is a waveform diagram of each part to explain the operation of the device shown in Fig. 1, and Fig. 3 is a diagram showing the relationship between the engine rotation speed and The battery voltage and current characteristic diagrams and FIGS. 4 to 8 are electrical circuit diagrams showing second to sixth embodiments of the device of the present invention. 1... Capacitor charging coil, 3a to 3d...
Reverse half-wave extraction diode, 4, 5, 6, 7...Voltage dividing resistor, thyristor, base resistor, forming a cutoff control circuit, 8... Transistor forming a short-circuit semiconductor switching element, 9, 10, 9a, 11 ……
Voltage dividing resistors, diodes, and thyristors constituting the high voltage response half-wave extraction circuit, 12...discharge blocking diode, 13...capacitor, 14...electronic ignition signal generation circuit, 14a...ignition signal generation circuit,
16...Ignition coil, 16a...Primary coil, 1
6b... Secondary coil, 17... Spark plug, 18...
An ignition thyristor forming a semiconductor switching element for ignition, 20...a battery as another load, 2
3,40... Lamp as another load.

Claims (1)

[Scope of Claims] 1. A generating coil of a magnet generator, a short-circuiting semiconductor switching element that substantially shorts the half-wave output of one of the generating coils, and a short-circuiting semiconductor switching element that sufficiently flows through the short-circuiting semiconductor switching element. a cut-off control circuit for cutting off the short-circuiting semiconductor switching element when the short-circuiting semiconductor switching element is turned off; a capacitor that is charged by the high voltage induced in the generating coil when the shorting semiconductor switching element is cut off; an ignition coil having a secondary coil; a reverse half-wave extraction diode for supplying the other half-wave output of the generating coil to another load; and an ignition signal generation circuit that generates an ignition signal at the ignition timing; The ignition signal from the ignition signal generation circuit conducts the charge in the capacitor to one of the ignition coils.
A non-contact ignition device for an internal combustion engine, comprising an ignition semiconductor switching element for supplying ignition to a secondary coil, and an ignition plug connected to a secondary coil of the ignition coil. 2. A generating coil of a magnet generator, a short-circuiting semiconductor switching element that substantially shorts the half-wave output of one of the generating coils, and a short-circuiting semiconductor switching element that short-circuits the short-circuiting semiconductor switching element when a sufficient short-circuit current flows through the short-circuiting semiconductor switching element. an ignition coil having a cutoff control circuit for cutting off the switching element, a capacitor charged by a high voltage induced in the generating coil when the short-circuiting semiconductor switching element is cut off, and a primary coil and a secondary coil. , a reverse half-wave extraction diode for supplying the other half-wave output of the generating coil to another load, and detecting a high voltage induced in the generating coil when the short-circuiting semiconductor switching element is cut off; A high voltage responsive half wave output circuit that continues to supply one half wave output of the generator coil to the other load or another load different from this load each time the high voltage exceeds a set value; A discharge blocking diode connected in series in the charging circuit, an ignition signal generation circuit that generates an ignition signal at the ignition timing, and conduction by the ignition signal from this ignition signal generation circuit to transfer the charge in the capacitor to the ignition. A non-contact ignition device for an internal combustion engine, comprising an ignition semiconductor switching element for supplying ignition to a primary coil of a coil, and an ignition plug connected to a secondary coil of the ignition coil.