JPS58195065A - Contactless ignition device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To well charge a capacitor through a charging coil having a small number of winding turns, by disconnecting a switching element parallelly connected to the capacitor and charging the capacitor with high voltage induced in the coil. CONSTITUTION:If an output in the direction of an arrow head is generated in a capacitor charging coil 3, the output of the coil 3 is short-circuited by a transistor 12 to surely charge a capacitor 22 without delay of a charge. If voltage reaches a preset value, a Zener diode 23 is conducted to flow a current in a thyristor 1, and the capacitor 22 is charged while a short-circuit current flows in the thyristor 1 and inceases, if voltage at a point (a) of a divider circuit increases to reach a preset value, a thyristor 14 is conducted to rapidly cut off the short circuit current. This high voltage fully charges a capacitor 6, then an ignition signal is generated in an ignition signal generator 9 by a generated output of a timing sensor 8 to conduct a thyristor 10 and obtain an ignition spark in a spark plug 11.

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, this kind of thing has been used to charge capacitors. l! Voltage f:
In order to make the s-function rotation speed almost uniform from low speed to high speed, the charging source for the capacitor is a low-speed coil with a thin wire diameter and a large number of turns, which mainly charges the capacitor during low-speed rotation, and a thick m
It consisted of a high-speed coil with a small number of turns that charged the capacitor mainly during high-speed rotation, and the capacitor was charged directly by the output of these two coils. Previously, the output of the capacitor charging coil was made into a constant voltage by a constant voltage circuit and used as a constant voltage source for the ignition signal generating circuit.

However, as mentioned above, in the nine conventional o4bo, (1) as the capacitor charging coil μ, there are 02 for low speed and high speed as mentioned above.
It requires M-class coils, making the structure complicated.

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

(3) Increase the secondary voltage at low speed, that is, the capacitor voltage,
The heat resistance of the conductor element is insufficient.

(4) −y > , > , □9・1:・′i turn □□6
1.8 Largely, a sufficient constant voltage output of the ignition signal generation circuit cannot be obtained at low speeds, and due to the increase in the number of capacitor charging coils at high speeds, a constant voltage circuit with a large capacity is required. . There are problems such as.

In order to solve the above problem, the present invention substantially short-circuits the capacitor f charging coil μO @ raw output by a short-circuiting semiconductor switching element connected in parallel with the capacitor. The capacitor is charged by the high voltage induced in the capacitor charging coil, and the short-circuit current when the short-circuit semiconductor switching element conducts is used to operate the constant voltage circuit of the ignition signal generation circuit. By using a capacitor charging coil μ with a small number of turns, the capacitor can be charged well, and a sufficient constant voltage output can be obtained even at low speeds as a constant voltage circuit for an ignition signal generation circuit, and the constant voltage circuit element can be miniaturized. The purpose of this book is to provide non-contact ignition devices for engines 6゜ ::□! llj.

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

First, in the first embodiment shown in FIG.
．． 3-1. (U), the number of windings is about 1/10 less than that of the conventional method (for example, 200 to 600 turns).

5Fi rectifier diode, 6 a capacitor charged by the capacitor charging side half-wave output of the capacitor charging coil 3, 7 an ignition coil, and 7a its primary coil 7b
is its secondary coil. 8 is a timing sensor that generates an output signal at a reference position, and 9 receives the output signal of the timing sensor 8 as an input, and operates as a constant voltage source using the output from a constant voltage circuit for an ignition signal generation circuit, which will be described later, for charging a capacitor, for example. This is a known electronic ignition signal generation circuit that electronically determines ignition timing by electric discharge and generates an ignition signal. The thyristor 1O becomes conductive when the ignition signal from the ignition signal generation circuit 9 is applied to its gate, and supplies the charged charge of the capacitor 6 to the primary coil/L/7a of the ignition coil A/7. This constitutes a semiconductor switching element for ignition. It is an ignition frame that is connected to the 2★Pre-+★ Ushikyo Kikoji Coil #7b of I1 company's ignition coil A/7 and is attached to the Y cylinder head of an internal combustion engine. 12 is a collector connected between the terminals of the capacitor charging coil 3 via a thyristor l
The emitter path is connected to charge the capacitance of this charging coil 3 [11] A transistor that short-circuits the half-wave output via a thyristor l, and a short-circuiting semiconductor switching element th
to be accomplished. 13 is a nine-base resistor connected between the collector and pace of the transistor 12, 14 is a thyristor whose anode-cathode path is connected between the base and emitter of the transistor 12, and 15.16t1 is a thyristor l connected between the terminals of the capacitor charging coil 3. The voltage dividing resistors are connected in series with each other, and the voltage dividing point a thereof is connected to the gate of the thyristor 14.

The base resistor 13, thyristor 14, and voltage dividing resistors 15 and 16 constitute a one-off control circuit 24 for dialyzing the transistor 12.

Reference numeral 17 denotes a diode for flowing a normal flow into the primary coil A/7a of the ignition coil A/7 to lengthen the arcing time of the ignition plug 11. 18 is thyristor 1
The gate sensitivity adjustment resistor 19 is a diode that short-circuits the reverse half wave of the charging coil 3. 2° is a diode,
22 is a DC power supply capacitor, 23 is a constant voltage Zener diode with a 1η current as a source, and 2 is a gate resistor of thyristor 1. A constant voltage circuit 25t for large signal generation circuit is constructed.

Next, the operation of the above configuration will be explained.

When a 12-pole magnet generator is used as the magnet-generated VIL machine, six cycles of no-load AC voltage are generated in the capacitor charging coil ~3 per one rotation of the rotor of the magnet N111 machine. Now, in the direction of the solid arrow in Figure 1, (capacitor charge %t11
When half-wave) output begins to occur, Koi/I/3 → lt anti-i
3 → Transistor 1 in the circuit of transistor 12's pace emitter diode 20 - capacitor 22 - ground
Base current flows through 2, and this transistor 2:'
l,', 14, emitter Ir, 44JIIJ, the output of coil 3 is substantially short-circuited.

Hi, capacitor 22i! ) When the charging voltage of the octopus capacitor 22, which is charged via the low-impedance circuit consisting of the transistor 12, reaches the set value, the Zener diode 23 becomes conductive and the thyris! Make l conductive. In this case, as the capacitor 22 is charged to a constant voltage, the short circuit current flowing through the fungistor 12 (coil/L/3) starts to flow through the thyristor lt, and the short circuit current increases. With this increase in short circuit current, Tofunjis! The voltage drop between the collector and emitter of 12 becomes large, and the voltage at the connection point a of the voltage divider circuit made up of resistors 15 and 16 increases. When this voltage reaches the set value, the thyristor 14
4, which short-circuits the space and emitter of the transistor 12, so that the short-circuit current is abruptly cut off from the collector to the emitter of the transistor 12. At this time, a large zero conduction voltage is generated in coil 3, and 1□
'1 occurs, and this high voltage is applied to: y+6. If
ijllllllll...shi, ii -F 5-h :2
Charge the battery sufficiently using the circuit from 7A7゜6 to diode 17 to ground. Next, using the constant voltage output of the constant voltage circuit 25 as a power source, the timing sensor 8 generates the output K j I point signal f generating circuit 9 electronically calculates the ignition timing and generates the ignition signal. An ignition signal is applied to the gate circuit of thyristor 1υ, making this thyristor 10 conductive. Due to the conduction of this thyristor IO, the charge of the capacitor 6 L1 capacitor 6 → thyristor 10 → ignition coil/I/7 is discharged in the circuit of the primary coil A/7a, and the ignition coil IV7C) secondary coil/L/ A high voltage is generated at 7b, and an ignition spark is obtained at the ignition plug 11.

In the above embodiment, when the short-circuit current of the transistor 12 reaches a constant value, the second transistor 2 is cut off, so that the current flowing through the thyristor 1 can be kept almost constant regardless of the engine speed. , therefore constant voltage circuit 2
A small circuit element with a small current capacity can be used as the circuit element of 5, and even when the engine is running at 4# and speed, the capacitor 22 can be sufficiently charged when the transistor 12 is conducting, so that a sufficient constant voltage can be maintained. It has the excellent effect of being able to obtain output.

FIG. 2 shows a second embodiment of the device of the present invention, in which, in contrast to the first embodiment, the half-wave output of the charging coil 3 which is not used for charging the capacitor is provided by a diode 19&.

19'F) to the battery 26, and when the voltage of the charging coil *3oi14 when the transistor 12111 is disconnected exceeds a predetermined value, it is detected by the diode 27 and the voltage dividing resistor 'lA28.29. The thyristor 30 is made conductive, and the thyristor 30 and the diode 31t''
An excess of the half-wave output on the capacitor charging side of the charging coil IL/3 is also supplied to the oversized battery 26 through the capacitor charging coil 1L/3. In this Fig. 2, 32 is charging coil lv3
When the half-wave output on the side that is not used for capacitor charging exceeds a predetermined value, it becomes conductive and short-circuits this half-wave output.
This is a regulator that prevents battery 260 from being overcharged.

As described above, in the present invention, short-circuit light that substantially short-circuits the half-wave output of the capacitor charging coil [g8] When the short-circuit current due to the half-wave output reaches a set value, the short-circuiting semiconductor switching element for short-circuiting is cut off. Equipped with a control circuit,
When the short-circuit semiconductor switching element is disconnected, the ignition capacitor is charged by the induced high voltage, and the constant voltage circuit of the ignition signal generation circuit is operated by the short-circuit current. It has excellent effects as mentioned above.

(1) Conventionally, a capacitor charging coil required two types of coils: a thin wire with a large number of turns, and a thick wire with a small number of turns. The structure is simple and the body size can be reduced.

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

3) Do not use thin wire as a capacitor charging carp.
′ Since there is no problem with quality, problems with quality can be resolved.

(4) The input of the -11,1,voltage circuit for the ignition signal generation circuit is obtained by short-circuit current, and ``this short-circuit current is cut off at a nearly constant voltage from low speed to high speed. A stable input/output voltage can be ensured from low speed to high speed.
Since no load is applied to the constant voltage circuit element Kjl such as a Zener diode, the size can be reduced.

[BRIEF DESCRIPTION OF THE DRAWINGS] Figures 1 and 112 show the devices of the present invention,
5j! FIG. 2 is an electrical circuit diagram showing an example. 3- Condenser charging coil, 6- Condenser. 71 ignition coil, 71! L-Primary coil, 7t)-Secondary coil, 9-Ignition signal generation circuit, 10-Iristor as a half-four-body switching switch for ignition, 11-Ignition plug, 1
2- Tofungis as a short-circuit semiconductor switching element 1, 24- Fresh control circuit, 25- Constant voltage circuit for ignition signal generation circuit. Representative Patent Attorney Takashi Mabe □ ■, -01,. □'1

Claims (1)

[Claims] (1) A capacitor charging coil p of a magnet generator, a short-circuiting semiconductor switching element that substantially shorts the output of this charging coil, and a short-circuiting semiconductor switching element that short-circuits when the short-circuit current flowing through this short-circuiting semiconductor switching element reaches a set value. A disconnection control circuit for disconnecting the switching element, and the charging coil at the time of AV# of the semiconductor switching element for shorting.
a capacitor charged by a high voltage induced in the
An ignition coil having a primary coil and a secondary coil is connected in series with the semiconductor switching element for short-circuiting, and outputs a constant voltage using the output supplied (from the charging coil) when the semiconductor switching element for short-circuiting is conductive. A constant voltage circuit for an ignition signal generation circuit that generates ignition signal, an ignition signal generation circuit that generates ignition No. 14 using the constant voltage output of this constant voltage circuit as a power source, and an ignition signal from this ignition signal generation circuit. an ignition semiconductor switching element for supplying the charged charge of the capacitor to the primary coil of the ignition coil; and an ignition plug connected to the secondary coil of the ignition coil. Fire device. Q) The constant voltage circuit has a series circuit of a diode and a power supply capacitor, and is connected in parallel with this series circuit,
2. The ignition device according to claim 1, further comprising a regulator that conducts the direct current when the terminal voltage of the capacitor exceeds a predetermined value.