SU1465612A1 - Electronic ignition system of i.c. engine - Google Patents

Abstract

This invention relates to equipment for internal combustion engines. The purpose of the invention is to increase the reliability of engine start-up and operation when exposed to temperature changes and system supply voltage. For this purpose, an auto-adjustment scheme is introduced for the shift of the key transformer 3 of the converter. The circuit consists of the regulating transistor 30, the collector-emitter section of which is connected in series with the bias resistor 9 and the power resistor 8, the inverter 31, the output of which is connected to the base of the regulating transistor 30, a series circuit of the fourth resistor 29 and the third zener diode 28, one of which is connected with the cathode of the rectifying diode 18, and the other with the input of the inverter 31. 1 Il.

Description

The invention relates to electrical equipment for internal combustion engines.

The purpose of the invention is to increase the reliability of starting and operation of the engine when exposed to changes in temperature and supply voltage of the system by introducing an autoregulation circuit for the bias of the key transistor of the pre-jq generator.

The drawing shows a diagram of an electronic ignition system.

I

The electronic ignition system contains a single-cycle transistor converter, the transformer I of which contains an emitter winding 2, the first terminal of which is connected to the first power bus, the second terminal of the winding 2 is connected to the emitter of the transistor switch 3, the collector of which is connected to the second power bus, feedback winding 4 , the first output of which is connected to the base of the transistor key. 3, connected to the first output of the base capacitor 5, the second output of which is connected to the cathodes of the first diode 6 and the first zener diode 7, the anodes of which are connected to the emitter and collector of the transistor switch 3, respectively, a power resistor 8, the first output of which is connected to the emitter of the transistor switch 3 , bias resistor 9, the first terminal of which is connected to the second 35th power bus, the output winding 10 of transformer 1, connected via a charging diode 11 to the first terminal of the storage capacitor 12, the second terminal of which through The primary 40 winding 13 of the ignition coil 14 is connected to the first power rail, to which the thyristor 15 cathode is connected, the anode of which and the diode 16 cathode are connected to the first output of the storage capacitor 45, the anode of the diode 16 is connected to the 'second power bus, additional transformer I7 winding 1, the first terminal of which is connected through a rectifying diode 18 with the first terminal of the filtering capacitor 19, * the second terminal of which is connected to.

a second power bus and with a second output of the additional winding 17, the contacts of the chopper 20, the first of which is not connected through the first resistor 21 to the connection point of the cathode of the rectifier diode 18. and the first output of the filtering capacitor, and through the second diode 22 in the forward direction and the first capacitor 23 with the control electrode of the thyristor 15, the second contact of the chopper 20 is connected to the second power bus, a common connection point of the second diode 22 and the first capacitor 23 through the second capacitor 23 and the second resistor 25 connected in parallel connected to a second power bus, to which a thyristor 15 control electrode is connected via a third resistor 26, which is connected to a cathode of a second zener diode 27, an anode of which is connected to a first power bus, a third zener diode 28, a fourth resistor 29, a regulating transistor 30 and an inverter 31, an input which through a series-connected third zener diode 28 and a fourth resistor 29 is connected to the cathode of the rectifier diode 18, the output of the inverter 31 is connected to the input of the regulating transistor 30, the emitter-collector section of which is connected between second terminals of the power resistor 8 and 9 displacement.

The ignition system operates as follows.

When a voltage is applied, a supply voltage appears on the emitter of the transistor switch (transistor) 3, which flows through the emitter winding 2 of the transformer, 1, Transistor 3 is unlocked by the bias applied to. its base through the feedback winding 4 of the output of the bias control circuit, comprising a power resistor 8, a regulating transistor 30 and a bias resistor 9.

At the time of power-up, the bias is maximum, determined by the ratio of resistors 8 and 9, since the transistor 30 is completely open, because the capacitor 19 is not charged, that means there is no signal based on the inverter 31, the collector voltage of the transistor 30 is the full voltage of the power source, which transistor 30 is open , When a current appears in winding 2, a positive feedback signal appears in winding 4, which transistor 3 jumps in, the current in winding 2 rises linearly to saturate the core of transformer 1, after which voltage e in the windings decreases and then changes

1465612 polarity, which leads to an abrupt closing of the transistor 3. The magnetic energy stored in the core of the transformer, 'in the form of a pulse of reverse polarity is supplied through the diode 18 and 11 to the charge of the capacitors 19 and 12, which receive portions of charges, the circuit returns to its original state. The cycles are repeated until the capacitors are fully charged, and as they are charged, the amplitude of the pulses increases, and when it reaches the stabilization voltage of stiliter 15 of 7 for windings 2 and 4, it will open and the base capacitor 5 will be charged with current through it so that the base of the transistor 3 appears a positive voltage covering the transistor applied to the base relative to the emitter through the diode 6. The appearance of this voltage leads to a delay in the opening of the transistor 3, i.e. to reduce the frequency of the general. tion, the amplitude of the pulses is stabilized, - the current consumption decreases to the value of the open circuit current. However, it must be large enough to ensure operability at low temperatures and supply voltage and depends on the conductivity of the arm of the divider that sets the offset. If the arm is unregulated, then the idling current remains large, a number of elements of the device heats up, which leads to overheating of the system and refuse.

base transistor amplifier inverter

31, the ac output of the collector to the base of the bias regulating transistor.

The principle of operation of the control circuit is that the conductivity of the transistor 30 is maximum when the output channel voltage is absent or less than the opening voltage of the zener diode 28 of the comparison circuit and, conversely, when the output channel voltage exceeds the opening threshold of the zener diode 28, the transistor conductivity decreases. The ability to control the mode of the transistor 3 by changing the conductivity of the offset arm over a wide range allows you to get rid of disturbances in the system when exposed to changes in temperature and supply voltage over a wide range. Further, when the storage capacitor 12 is charged, when the contacts of the interrupter 20 are opened, a starting pulse appears, which through the diode 22 and the capacitor 23 enters the starting electrode of the thyristor 15, it opens, the capacitor 12 is discharged to the primary winding 13 of the ignition coil 14, while the secondary winding of the coil there is a high voltage pulse supplied to the spark plugs of the engine through the ignition distributor,

After the discharge of the capacitor 12, the thyristor 15 is restored and the charge process of the capacitor 12 begins again. Capacitor Voltage 19

Introduced into the system, the bias control circuit of the key transistor of the converter allows you to automatically change the bias by adjusting the conductivity of the bias arm by introducing a bias transistor 30 into it, the emitter junction of which is connected in series with the bias resistor 9, which changes the overall bias of the bias arm in the required operating conditions. The transistor 3 is controlled from a comparison circuit performed on a hundred * ”bilitron 28, the input signal of which is the voltage of the DC output channel of the converter obtained at the filter capacitor 19 of the output of the voltage channel connected through the diode 18 to the transformer winding 17. The output signal of the comparison circuit arrives at almost constant, because only the difference between the winding voltage of 1 7 and the stabilization voltage of the zener diode 28 is used to control the bias control circuit * *

The control circuit has a high sensitivity, therefore, it ensures the operability of the devices, optimally when the voltage, load and ’5Q temperature change over a wide range.

Claims (1)

Claim An electronic ignition system for internal combustion engines containing a single-phase transistor converter, the transformer of which contains an emitter winding, the first terminal of which is connected to the first power bus, the second terminal is connected to the emitter of the transistor key, the collector of which is connected to the second power bus, feedback winding, the first output which is connected to the base of the transistor switch connected to the first terminal of the base capacitor, the second terminal of which is connected to the cathodes of the first diode and the first a zener diode, the anodes of which are connected respectively to the emitter and collector of the transistor switch, a power resistor, the first output of which is connected to the emitter p of the transistor switch, a bias resistor, the first output of which is connected to the second power bus, the output winding of the transformer connected through the charging diode to the first conclusion _{2 |} storage capacitor, the second terminal of which through the primary winding of the ignition coil is connected to the first power line, to which the thyristor cathode is connected, the anode of which 2 is connected to the first output of the storage capacitor, which is connected via a dyad to the second power line, an additional transformer winding, the first terminal of which is connected through a rectifying diode to the first terminal of the filtering capacitor, the second terminal of which is connected to the second supply bus, the second terminal of the additional winding is connected to the second with the output of the filtering capacitor and the second supply bus, breaker contacts, the first of which is connected through the first resistor to the junction point of the rectifier diode cathode with the output of the filtering capacitor, and through the second diode in the forward direction and the first capacitor - with the thyristor control electrode, the second the contact of the chopper is connected to the second power bus, the common point of connection of the cathode of the second diode, and the first capacitor is through the parallel connection of the second capacitor and the second. The resistor is connected to the second bus not a power supply, to which a thyristor control electrode is connected through a third resistor, which is connected to the cathode of the second zener diode, the anode of which is connected to the first power bus, characterized in that, in order to increase reliability, a fourth resistor, a third stub 5 liter, is introduced, a control transistor and an inverter, the input of which through a third zener diode and a fourth resistor is connected in series with the cathode of a rectifier diode, the output of the inverter is connected to the input of a control transistor, the emitter - collector section torr which is connected between the second terminals of the power and bias resistors.