JPS59221465A - Capacitor discharge type internal-combustion engine ignition device - Google Patents

Abstract

PURPOSE:To facilitate the turn off a thyristor by a method wherein a switch circuit, controlled by a thyristor igniting signal from a signal supplying circuit to short full-wave rectifying voltage, is provided between the D.C. output terminals of a full-wave rectifying circuit. CONSTITUTION:A signal, generated in a signal coil 11, is impressed on the base of a transistor 13 when the thyristor 8 is conducted upon an ignition timing and the charge of the capacitor 6 is discharged suddenly to a primary coil 2a, and the output terminal of the full-wave rectifying circuit 4 is shorted. When the ignition signal is reduced, the transistor 13 becomes non-conduct again. According to this method, the output voltage of the full-wave rectifying circuit 4 rises up after the discharging current, passing through the thyristor 8, is terminated, therefore, the interception of the thyristor 8 and the re-charging of the capacitor 6 may be effected surely.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a capacitor discharge type internal combustion engine ignition system that charges an ignition energy storage capacitor by full-wave rectifying the AC output voltage of a magnet generator. It is.

[Prior art] As a capacitor discharge type internal combustion engine ignition system, a circuit is known in which an alternating current voltage is full-wave rectified to charge an ignition energy storage capacitor.
-17135). When a full-wave rectified voltage is used to charge the ignition energy storage capacitor, there is an advantage that the capacitor can be charged efficiently, but on the other hand, when the discharge control thyristor conducts, the discharge current of the capacitor increases. The output current of the full-wave rectifier circuit flows through the thyristor before the current drops below the holding current of the thyristor, making it difficult to turn off the discharge control thyristor and thus making it impossible to recharge the capacitor. In order to eliminate this drawback, in a device that uses a trannostar % swing type DC-DC converter as a power source for charging the ignition energy storage capacitor, a certain period of time e.g. DC-DC
There is a method for stopping the oscillation of a converter (for example, Japanese Patent Application Laid-Open No. 49-804-35). However, in a device that charges the ignition energy storage private capacitor by full-wave rectifying the AC output voltage of the exhaust coil installed in the magnet generator, the generation of the AC output voltage is periodically performed while the magnet generator is rotating. Since it is not possible to stop the ignition energy for a short period of time, a method has conventionally been used in which the AC output voltage of the exciter coil is half-wave rectified to charge the ignition energy storage capacitor.

Purpose of the Invention The purpose of the present invention is to fully rectify the alternating current output voltage of an exciter coil provided in a magnet generator so that the discharge control risk can be reliably cut off even when the ignition energy storage capacitor is charged. An object of the present invention is to provide a capacitor discharge type internal combustion engine ignition device.

Structure of the Invention The present invention includes an ignition coil having a primary coil and a secondary coil, and an exciter coil that is provided in a magnet generator that rotates in synchronization with the rotation of an internal combustion engine and that induces an alternating current voltage according to the rotation of the engine. , a full-wave rectifier circuit connected between both terminals of the exciter coil to output a full-wave rectified voltage, and an ignition energy storage provided on the primary side of the ignition coil and charged to one polarity by the full-wave rectified voltage. a discharge control capacitor provided to discharge the electric charge of the capacitor to the primary coil of the ignition coil when conductive, and a signal supply circuit that provides an ignition signal to the thyristor at the ignition position of the engine. A capacitor discharge type internal combustion engine ignition device, further comprising: a capacitor discharge type internal combustion engine ignition device, which is further connected between the DC output terminals of the full wave rectifier circuit and controlled by a sirisk ignition signal from the signal supply circuit; A short-circuit switch circuit is provided to substantially short-circuit between the DC output terminals of the DC output terminals. The conduction period of the short-circuit switch circuit is selected so as to continue at least until the capacitor release current due to conduction of the thyristor falls below the holding current of the thyristor and the thyristor is turned off. If configured as above, the output current of the full-wave rectifier circuit will not flow through the thyristor before the current flowing through the thyristor decreases below the holding current of the thyristor, so the turn-off of the thyristor will not occur. can be carried out reliably.

EXAMPLES Hereinafter, Kien Ryu will be explained in detail along with seven examples with reference to the drawings.

FIG. 1 shows an electric circuit according to an embodiment of the present invention.
In the figure, 1 is an exciting coil arranged in a magnet generator that rotates synchronously with the internal combustion engine, and 2 is an ignition coil consisting of a primary coil 2a and a secondary coil 2b. One ends of the cables 2a and 2b are commonly connected and grounded. Reference numeral 3 denotes a spark plug connected to the secondary coil 2b, and this spark plug is attached to a cylinder of an engine (not shown). One end 1a of exciter coil 1
and the other end 1b are connected to AC input terminals 4a and 4b of the single-phase full-wave rectifier 4, respectively.

The positive output terminal 4C of the single-phase full-wave rectifier 4 is connected to the diode 5.
The negative output terminal 4d of the full-wave rectifier circuit 4 is grounded. The cand of the ignition diodes 5 is connected to one end of the ignition energy storage capacitor 6, and the other end of this capacitor is connected to the non-ground terminal of the primary coil 2a of the ignition coil, and also to the anode of the ode 7. The cand of the O diode 7 is grounded. The anode of the discharge control cylindrical nostar 8 is connected to the connection point between the diode 50 cand and the capacitor 6, and the cand of the cyrisk 8 is grounded. A resistor 9 and a signal supply circuit 10 are connected between the dart can 19 of the thyristor 8 and a signal supply circuit 75; The signal supply circuit 10 is composed of a signal coil 11 which is provided in a magnet generator and has one end grounded, and diodes l 2 and 12' whose anodes are commonly connected to the other end of this signal coil 11. The cand 2' serves as the non-ground terminal 10a of the signal supply circuit 10 and is connected to the dart of the thyristor 8. The above circuit constitutes a capacitor discharge type ignition system, and the AC voltage induced in the exciter coil l is passed through a single-phase full-wave rectifier circuit 4, and the DC output voltage is applied to the positive output terminal 4 of the rectifier circuit 4.
C → diode 5 → capacitor 6 → damper diode 7
The capacitor 6 is charged to the polarity shown in the figure through a path from the primary coil 2a of the ignition coil to the negative output terminal 4d of the rectifier circuit 4. When an ignition signal is generated from the signal supply circuit 10 at the ignition position of the engine, the thyristor 8 becomes conductive, and the charge in the capacitor 6 is discharged through the thyristor 8 to the primary coil 2a of the ignition coil 2, causing ignition. The engine is ignited by the ignition Zorag 4 due to the high voltage induced in the secondary coil 2b of the coil.

The circuit of the above embodiment of the capacitor discharge type ignition device of the present invention further includes a transistor 13 having a collector and an emitter connected between the positive output 4C of the full-wave rectifier circuit 4 and ground, respectively. The pace of the transistor 13 is connected to the non-grounded output terminal 10m of the signal supply circuit 10 and the other end of a resistor 14 whose one end is grounded. This transistor 13 constitutes a short-circuit switch circuit that substantially short-circuits the DC output terminals of the full-wave rectifier circuit 4. Full wave rectifier circuit 4
Resistors 15 and 1 are also connected between the positive output terminal 4C and the ground.
A voltage divider circuit consisting of 6 series circuits is connected. A cand of a Zener diode 17 is connected to the connection point between the resistors 15 and 16, and an anode of the Zener diode 17 is connected to an anode of a diode 18 whose cand is connected to the pace of the transistor 13. Resistor 1 above
5 and 16 and Zener diode 17 and diode 1
8 constitute a voltage detection circuit 19, which applies a pace current to the transistor 13 when the instantaneous value of the DC output voltage of the full-wave rectifier circuit 4 exceeds a predetermined value. The transistor 13, the resistor 14, the box, and the pressure detection circuit 19 constitute a control circuit 20 that controls the voltage between the DC output terminals 4C and 4d of the full-wave rectifier circuit 4, and the signal supply circuit 10 has a thyristor 280 ignition circuit. During the period when No. 6 occurs, the transistor 13 conducts and short-circuits the DC output of the full-wave rectifier circuit 4, and when the instantaneous value of the DC output voltage of the full-wave rectifier circuit 4 rises above a predetermined value, zener diode 17
is conductive, making the transistor 13 conductive and limiting the magnitude of the DC output voltage of the full-wave rectifier circuit 4 to a predetermined value.

Is the above implemented? In the ignition system of J, the exciter coil 1 generates an alternating current pressure by the rotation of the magnet generator, and the signal coil 11 generates a pulse voltage once per ignition cycle of the engine. Figure @2 shows an example of a magnet generator that generates such voltages in the exciter coil 1 and the signal coil 11.
0 and a stator 40. The magnet rotor 30 is mounted on the inner peripheral wall of a bowl-shaped flywheel 31 made of magnetic material.
permanent magnets 32.32. ... are arranged and fixed at equal intervals, and these permanent magnets are magnetized in the radial direction of the flywheel 31 so that the magnetic poles on the inner circumferential side are alternately N and S poles. has been done. flywheel 31
A disk 33 is provided in the center of the bottom wall of the engine, and by fitting the disk portion 33 to the rotating shaft of the engine, the right rotor 30
It is designed to be installed on the engine. The stator 40 has magnetic pole parts at both ends! - It is constructed by arranging the exciter coil l and the generator coil 43 wound around the character-shaped iron cores 41 and 42, respectively, at 180° opposing positions. The generator coil 43 is used as a low-voltage power source for lighting the lamp, charging the battery, and the like.

The magnetic pole portions of the iron cores 41 and 42 are respectively arranged to face the inner circumferential magnetic pole of the magnet 32 with an air gap interposed therebetween. Further, a small permanent magnet 34 magnetized in the radial direction is fixed to the outer circumference of the flywheel 31 by adhesive or the like, and the signal coil 11 is attached to a fixedly arranged iron core 44 at a position facing this with an air gap interposed therebetween. It is wrapped. In the example shown in FIG. 2, when the magnet rotor 30 rotates once, two cycles of AC voltage are induced in the generator coil 1, and the permanent magnet 34 is connected to the iron core 4.
When passing through the magnetic pole portion of No. 4, a pulse voltage of cycle d and ■ cycle is induced in the signal coil J1.

Next, the operation of the first embodiment 11 will be explained. When the magnet rotor 30 shown in FIG. 2 rotates, a voltage Veo exhibiting a no-load waveform as shown in FIG. 3(a) with respect to time t is induced in the exciter coil 1. This voltage is full-wave rectified by the full-wave rectifier circuit 4, and a full-wave rectified voltage VRO having a no-load waveform shown by a chain line in FIG. 3(b) appears at the positive output terminal 4c of the full-wave rectifier circuit 4. . This rectified voltage causes diode 5
Since the charging current flows to the ignition energy storage capacitor 6 through the capacitor 6 and 7, the waveform of the load terminal voltage vR of the positive output terminal 4c of the full-wave rectifier becomes as shown by the solid line in FIG. 3(b). The capacitor 6 is charged with the polarity shown in FIG. 1, and the waveform of its terminal voltage ■c becomes as shown by the solid line in FIG.
'! will be charged. When the ignition signal vs having the waveform shown in FIG. 3(c) is generated from the signal coil 11 at the ignition timing of the engine, and its instantaneous value reaches the trigger level s of the discharge control thyristor 8 at time t2, this thyristor 8 becomes conductive, and the charge in the capacitor 6, which had been charged to the voltage VC, is rapidly discharged to the primary coil 2a of the ignition coil 2 through the thyristor 8.

At this time, the waveform of the discharge current 11 passing through the thyristor 8 is the third waveform.
The result will be as shown in figure (f). Capacitor 6 in primary coil 2a
When the discharge current rapidly flows, a high voltage is induced in the secondary coil 2b of the ignition coil 2, and a spark flies to the ignition glove 3, igniting the engine. In the ignition device of the present invention, the ignition signal vs generated in the signal coil 11 is also
0 pace is also applied, and when the ignition signal Vs reaches the trigger level Vt of the transistor 13 at time t, this transistor 13 becomes conductive and the DC output terminal 4 of the full-wave rectifier circuit 4
Short-circuit the voltage vR of c. The ignition signal VsO value is at time t3
When the voltage falls below the trigger level Vj of the transistor 13 again, the transistor 13 becomes non-conductive again and the short circuit of the DC output terminal 4c of the full-wave rectifier circuit 4 is released. That is, during the period (L3te) in which the transistor J3 is conductive by the ignition signal (18), the output voltage (2)R of the full-wave rectifier circuit 4 is substantially short-circuited and becomes zero. transistor 13
The time t1 when the thyristor 8 becomes conductive and the time t when the thyristor 8 becomes conductive
2 is substantially equal, so the period Ts during which the output voltage of the full-wave rectifier circuit 4 is short-circuited is approximately Ts=t3-t2.

By the way, the cascade time T(
3(f)), the inductances of the primary coil 2a and secondary coil 2b of the ignition coil are Ll and L2, respectively, and the capacitance of the ignition energy storage capacitor 6 and the secondary circuit of the ignition coil 20 is cl, respectively. and C2,1
The coupling coefficient and matching coefficient between the secondary coil 2a and the secondary coil 2b are k and u (=LI C1/
L2 C2), it can be approximately expressed by the following equation.

In the ignition device of the present invention, the value of the period T8 during which the output of the full-wave rectifier circuit 4 is short-circuited and the discharge current l passing through the thyristor 8
The ignition signal Vs from the signal coil 11 is set so that the relationship between the duration of l and the value of T is Ts T> (turn-off time of the thyristor 8) within the range of engine rotation speeds.
The pulse width and ignition circuit constant values are set.

Therefore, the output voltage of the full-wave rectifier circuit 4 rises again only after the discharge current 11 passing through the thyristor 8 ends.
There is no fear that the conduction of the thyristor 8 will continue, and the thyristor 8 can be shut off and the capacitor 6 can be recharged reliably.

Next, in the medium speed region of the rotation speed of the magnet generator, the no-load output voltage VR'O of the positive polarity output terminal 4c of the full-wave advection circuit 4
and the output voltage under load ■R' become higher as shown by the chain line and the broken line in Fig. 3(b), respectively, and the output voltage under load ■
When the instantaneous value of R' exceeds the predetermined value Vm, the voltage detection circuit 1
The voltage applied to the zener diode 17 of 9 reaches the zener level, and the zener diode 17 becomes conductive to supply a base current to the tranostor 13. Therefore, the transistor 13 becomes conductive, and the value of the pressure 16 of the DC output gun 4C of the full-wave rectifier circuit 4 is limited to vm. The waveform of the terminal voltage ■c' of the capacitor 6 in this case is shown in Figure 3 (d
) as shown by the broken line, and the value of the filling mlh pressure is ■□・
limited to. FIG. 4 shows the charging voltage V of the capacitor 6.
In the case of the above embodiment, the VcO value is limited to a constant value ■□ in the medium speed region, as shown by the solid line curve a. In the case of a capacitor discharge type ignition system that does not have a voltage detection circuit 19 and a transistor 13 as a short-circuit switch circuit, the charging voltage Vc of the capacitor 6 is particularly small as shown by the broken line in FIG. It becomes extremely high in the high speed region, and the capacitor 6 needs to have a high IT pressure.

In the above embodiment, the ignition energy storage capacitor 6 is provided in series with the primary coil 2& of the ignition coil,
The discharge control thyristor 8 is connected to the capacitor 6 and the primary coil 2.
Although the capacitor discharge type ignition circuit is provided in parallel to the series circuit with a, it is sufficient that the capacitor discharge type ignition circuit discharges the electric charge of the capacitor 6 to the primary coil 2a when the thyristor 8 becomes conductive. In Figure 1, capacitor 6
It is also possible to swap the positions of the thyristor 8 and the thyristor 8.

The mata tamper diode 7 can be omitted.

Further, in the above embodiment, the voltage detection circuit 19 has a voltage dividing resistor 1
5 and 16 and Zener diode 17 and diode 1
8, for example, a series circuit of a Zener diode and a current limiting resistor may be directly connected between the positive output terminal 4c of the full-wave rectifier circuit and the base of the transistor 13. Further, in the above embodiment, the magnet generator has a four-pole configuration, but any multi-pole generator with two or more poles can be used. Further, the signal coil 11 of the signal supply circuit 1o may be provided in a separate signal generator, or a conventionally known photoelectric type or monostable multivibrator type can be used as the signal supply circuit 10. In the above embodiment, a single-phase full-wave glitz result rectifier circuit is used as the full-wave rectifier circuit 4, but an intermediate terminal is provided in the exciter coil l to obtain a full-wave rectified output by a two-phase half-wave rectifier circuit. You can also.

Effects of the Invention As described above, according to the present invention, during the period when the discharge control cyrisk is conducting, the output terminal of the full-wave rectification circuit is short-circuited to perform full-wave rectification for charging the ignition energy storage capacitor. Since the circuit prevents the voltage from being applied to the discharge control thyristor, the discharge control thyristor can be shut off reliably and malfunction of the ignition device can be prevented.

[Brief explanation of drawings]

Fig. 1 is a connection diagram showing a circuit of an embodiment of the present invention, Fig. 2 is a front view showing an example of a magnet generator used in the invention, and Fig. 3 is an electrical connection diagram of each part of the embodiment of Fig. 1. (Pressure, frost, and flow waveform diagrams. Figure 4 is a diagram showing the characteristics of the ignition energy storage capacitor charging voltage with respect to the rotational speed for an embodiment of the present invention. l... Exciter coil, 2. ...Ignition coil, 3.
... Spark plug, 4... Full-wave rectifier circuit, 6... Ignition energy storage capacitor, 5, 7... Diode,
8... Cyrisk for discharge control, io... Signal supply circuit, 13... Transistor (short circuit switch circuit), 1
9... Voltage detection circuit, 20... Short circuit control circuit. Book 3

Claims (1)

[Claims] an ignition coil, an exciter coil provided in a magnet generator that rotates in synchronization with the rotation of the internal combustion engine and generates an alternating current voltage due to the rotation of the engine, and an exciter coil that is connected to the exciter coil and rectifies a certain output of the exciter coil. a full-wave rectifier circuit that outputs a full-wave rectified voltage, and an ignition energy storage capacitor that is provided on the primary side of the ignition coil and is charged to one polarity with the full-wave rectified voltage; A capacitor discharge type internal combustion engine ignition device comprising a 1j discharge control thyristor provided to discharge electric charge to the primary coil of the ignition coil, and a signal supply circuit that gives an ignition signal to the thyristor at the ignition position of the engine. , comprising a shorting switch circuit connected between the DC output terminals of the full-wave rectifier circuit and controlled by a SIRISK ignition signal from the signal supply circuit to substantially short-circuit the DC output terminals of the full-wave rectifier circuit. . A capacitor discharge type internal combustion engine ignition device, wherein the conduction period of the short circuit switch circuit is set to continue at least until the thyristor is turned off.