RU2182254C2 - Ignition system - Google Patents

Abstract

FIELD: capacitor ignition systems at continuous pulse accumulation of energy for internal combustion engine; transport facilities and power plants with any ignition coils. SUBSTANCE: proposed system includes DC converter, two energy storage capacitors, choke, electronic switch with signal and control inputs and one output, ignition coil, electronic switch control unit with two inputs (signal and control inputs) and two outputs, unit for turning-on electronic switch with two inputs and one double-pole output and capacitor. Electronic switch control unit includes two univibrators, 2 OR, 2NAND and NOT gates; output of 2NAND gate is first output of electronic switch control unit and output of not gate is its second output. Electronic switch of ignition system employs thyristor. EFFECT: enhanced reliability due to enhanced noise immunity of electronic switch control unit. 3 cl, 2 dwg

Description

 The invention relates to capacitor ignition systems with continuous pulse energy storage for internal combustion engines and can be used on vehicles and power plants with any type of ignition coil.

 Known universal thyristor ignition system (Russia, patent 2019726, F 02 P 3/00, Bull. 17, 1994). This system contains a switch, two electronic keys, a control device for these keys, made on element 2 OR NOT and having two inputs and one output, one of which is the input of the ignition system, two storage capacitors, a reverse diode, an ignition coil and five resistors.

 The positive output terminal of the DC / DC converter is connected to the power input of the second electronic switch and through the serial first disconnect contacts of the dual switch and the fourth resistor, in parallel with which a current-limiting resistor is connected, with the junction point of the reverse diode. The first terminal of the first electronic switch and the first terminal of the second storage capacitor, the second terminal of which is connected through the serial primary winding of the ignition coil and the fifth resistor with a minus power supply, the second terminal of the first electronic switch, the anode of the reverse diode and through the second electronic switch is connected to the negative output terminal of the converter . The control inputs of the electronic keys are connected to the output of the electronic key control device. The secondary winding of the ignition coil is the output of the ignition system.

This system has disadvantages:
- the complexity of the voltage stabilization device of the Converter due to the separation of its negative output from the common bus;
- unstable, increasing amplitude of the pulses in the packet, which reduces the average energy in the packet of pulses, mandatory tuning to an underestimated value of the pulse amplitude at the beginning of the packet due to the danger of exceeding its permissible values for circuit elements, and therefore the breakdown of the spark gap from the first pulses in the pack may not occur, while the ignition will be later than required;
- low reliability due to the low noise immunity of the electronic key control device at the time of breakdown of the spark gap;
- the presence of through currents when switching electronic keys, current-limiting resistors and a resistor current sensor, which reduce the efficiency of the ignition system;
- not interchangeability with industrial ignition systems.

 These shortcomings are due to the fact that this circuit is a voltage multiplier, because of which the amplitude of the pulse at the beginning of the pulse train is equal to the voltage at the output of the DC-DC converter, the amplitude of the second pulse is the sum of the voltage on the converter and the residual voltage of the first pulse after transferring part of its energy to the spark , the amplitude of the third pulse is equal to the sum of the voltages on the converter and the residual voltage of the second pulse after the transfer of part of its energy to a spark, etc. Thus, the amplitude in the pack will depend both on the gap in the spark plug, since with an increase in the gap more energy is consumed for spark formation, and on the temperature conditions when starting a cold engine, changing the equivalent gap in the spark plug. Through currents when switching keys arise due to the fact that it takes time to lock the keys, and there are no elements in the system that determine when the keys are locked. Non-interchangeability with existing ignition systems is due to the peculiarities of connecting the ignition coil, since in existing ignition systems one of the terminals of the primary winding of the ignition coil is connected to the primary power source - the battery or to the common bus.

 Also known is the ignition system (RU, Pat. 2115016, Bull. 19 from 07/10/98), which is taken as a prototype of the invention. This system contains a DC voltage converter, two storage capacitors, a choke, two electronic keys, an electronic key control device that has four input terminals and two output, a reverse diode and an ignition coil.

 The output of the DC / DC converter is connected to one terminal of the first storage capacitor and one terminal of the inductor, the second terminal of which is connected to the first input of the key management device and the input of the first electronic key, the output of which is connected to the second input of the key management device, one terminal of the second storage capacitor, the reverse cathode diode and the input of the second electronic key. The output of this key is connected to the third input of the electronic key control, the anode of the reverse diode and one output of the primary winding of the ignition coil, the output of the secondary winding of which is the output of the ignition system. The second terminals of the storage capacitors, the windings of the ignition coil and the common terminal of the converter are connected to a common bus. The fourth input of the electronic key control device is the input of the ignition system.

 The disadvantages of the prototype are the complexity of the design (electrical circuit), low efficiency due to losses on the second power switch and reverse diode and insufficient spark energy due to pauses (during the voltage transfer from the first storage capacitor to the second) in the current flowing in the primary winding of the coil ignition.

 The technical result of the invention is to eliminate the disadvantages of the analogue and prototype and increase the reliability of the ignition system by increasing the noise immunity of the electronic key control device.

 This result is achieved due to the fact that the ignition system contains: a constant voltage converter, two storage capacitors, a choke, an electronic key (EC) with a signal and control inputs and one output, an ignition coil, an electronic key control device (UUEK) with two inputs - a signal and controlling both the first and second outputs, an electronic key switch device (UVEC) with two inputs and one bipolar output and a capacitor. The signal input of the UUEK is the input of the ignition system.

 The output of the DC / DC converter is connected to one terminal of the first storage capacitor and one terminal of the inductor, the other terminal of which is connected to the input of the EC and one pole of the output of the UVEC, the second pole of the output of UVEC is connected to the control input of the EC. The output of the EC is connected to one terminal of the second storage capacitor and one terminal of the primary ignition winding. The connection point of these conclusions is the output of the control signal of the ignition system and is connected to the control input of the UUEK. One of the conclusions of the secondary winding of the ignition coil is the output of the ignition system. The first output of the UUEK is connected to one input of the UVEC, and the second output of the UUEK is connected to another input of the UVEC, to which one terminal of the capacitor is connected, the second output of which is connected to the negative bus of the power supply (with a common bus). Other terminals of the storage capacitors and the common terminal of the DC / DC converter are connected to the negative bus of the power source (to the common bus), and the other conclusions of the windings of the ignition coil are connected to the negative or positive buses of the power source.

 The electronic key control device (UUEK) contains two one-shots, elements 2OR, 2I-NOT and NOT. The input of the first one-shot is connected to the signal input of the UUEK and one input of the 2I-NOT element, the input of the second one-shot is connected to the output of the EC (control signal output) and the input of the element NOT. The output of the first one-shot is connected to one input of the OR element 2, the output of the second one-shot is connected to the other input of the 2 OR element, the output of which is connected to the second input of the 2AND element. The output of the 2I-NOT element is the first output of the UUEK. The output of the element is NOT the second output of the UUEK.

 Distinctive features of the invention are: an electronic key switch device (UVEC) and a capacitor, with one input of the UVEC connected to the first output of the UUEK, and the other input of the UVEC connected to the second output of the UUEK and one output of the capacitor, the other terminal of which is connected to the negative bus of the power source (with shared bus), in addition, one pole of the UVEC output is connected to the signal input of the EC and the second output of the throttle, and the other pole of the output of UVEC is connected to the control input of the EC, in addition, the output of the EC is connected to one output of the second accumulate ln capacitor, one output of the primary ignition coil and the control input of the UUEK.

 Distinctive features exclude the possibility of reconnecting the electronic key (EC) at the time of breakdown of the spark gap, which prevents failure or malfunction of the ignition system and thereby increases its reliability.

 The design of the ignition system and its operation is illustrated by drawings.

 In FIG. 1 is an electrical diagram of an ignition system according to the invention.

 Figure 2 shows a possible electrical circuit UVEC.

The following notation is introduced in the figures:
1 - DC voltage converter;
2 - the first storage capacitor;
3 - throttle;
4 - electronic key - thyristor (EC);
5 - the second storage capacitor;
6 - electronic key control device (UUEK);
7 - ignition coil;
8 - electronic key switch device (UVEC);
9 - capacitor;
10 - the first one-shot;
11 - the second one-shot;
12 - element NOT;
13 - element 2 OR;
14 - element 2I-NOT;
R is the resistor;
U - thyristor optocoupler.

 Converter 1 can be made according to the scheme of the converter of low DC voltage to a higher DC voltage according to known schemes, in which the input and output negative terminals are interconnected and form a common output of the converter connected to the negative bus of the power source (with a common bus). The input of the Converter 1 is connected to the output of the primary power source, such as a battery.

 As a storage capacitor 2, for example, a capacitor of type K 50-27-450 V-100 μF can be used, and as a storage capacitor 5, a capacitor of type K 73-17-630V-1.0 μF can be used.

 The inductor 3 can be made in the form of an inductor on an open magnetic core.

 As an electronic key, a thyristor, for example, of the type KU221A, can be used.

 UUEK 6 can be performed according to the scheme of figure 1 (pos. 6).

 As the ignition coil 7 can be applied to any commercially available ignition coil, for example B-116.

 As the device 8 for switching on the electronic key, a thyristor optocoupler U of type AOU103B can be used (Fig. 2).

 As the capacitor 9, a ceramic capacitor of the type KM-5-30V-68N can be used.

 Single vibrators 10 and 11 can be performed according to known schemes on the K561LA7 chip, while at the input of a single vibrator 11 there must be a restriction chain of a zener diode and a resistor, due to the high level of the signal supplied to its input from the output of the electronic key (not shown in the diagram) .

 Element HE 12 can be performed on the chip K561LA7.

 As element 2 OR 13 can be applied chip K561LS2.

 As an element 2I-NOT 14 can be applied chip K561LA7.

 The power source can be a rechargeable battery charged from the vehicle’s electric generator.

 The ignition system according to the invention can be performed according to the electric circuit of FIG. 1 and comprises: a DC-voltage converter 1, two storage capacitors 2 and 5, a choke 3, an electronic thyristor switch (EC) 4 with signal and control inputs and one output, a coil 7 ignition, electronic key control device (UUEK) 6 with two inputs - signal and control and first and second outputs, electronic key switch device (UVEK) 8 with two inputs and one bipolar output and capacitor 9.

 The output of the DC-DC converter 1 is connected to one terminal of the first storage capacitor 2 and one terminal of the inductor 3, the other terminal of which is connected to the input of EC 4 and one pole of the output of UVEC 8. The output of EC 4 is connected to one terminal of the second storage capacitor 5 and one terminal of the primary winding ignition. The connection point of these terminals is the output of the control signal of the ignition system and is connected to the control input of UUEK 6. The first output of UUEK 6 is connected to one input of UVEK 8, and the second output of UUEK 8 is connected to another input of UVEK 6, to which one capacitor 9 is connected, and the second the output of which is connected to the negative bus of the power supply (with a common bus). The second pole of the output of UVEC 8 is connected to the control input of EC 4. The other terminals of the storage capacitors 2 and 5 and the common terminal of the DC-DC converter 1 are connected to the negative bus of the power supply (to the common bus), and the other conclusions of the windings of the ignition coil 7 are connected to the negative or positive power supply busbars. One of the conclusions of the secondary winding of the ignition coil 7 is the output of the ignition system.

 The electronic key control device (UUEK) contains two single vibrators 10 and 11, elements: NOT 12, 2 OR 13, 2 AND NOT 14. The input of the single vibrator 10 is connected to the signal input of the UUEK 6 and one input of the 2I-NOT 14 element, the input of the other single vibrator 11 is connected with the output of EC 4 (control signal output) and the input of the HE 12 element. The output of the first one-shot 10 is connected to one input of the 2 OR 13 element, the output of the second one-shot 11 is connected to the other input of the 2 OR 13 element, the output of which is connected to the second input of the 2AND-14 element The output of element 2 is NOT the first output. 8. UUEK th output of NOT circuit 12 is a second output UUEK 6.

где L - индуктивность дросселя 3;
С - емкость последовательно соединенных конденсаторов 2 и 5.The ignition system operates as follows (figure 1). When the power is turned on, the converter 1 charges the storage capacitor 2 to the rated voltage. There is no voltage at the second storage capacitor 5 yet. In this regard, at the output of the element HE 12 there is a logical voltage "1", which charges the capacitor 9. After the signal is received at the signal input of the UUEK 6, a single-shot 10 is launched, the pulse from the output of which through the element 2 OR 13 generates a pulse at the output of the element 2 AND-NOT 14 voltage logical "0". In this case, when the capacitor 9 is discharged through the UVEC 8, the output of the last signal arises, opening the electronic key 4. The second storage capacitor 5 is charged from the capacitor 2 through the inductor 3, which limits the current through the key 4. The capacitance of the capacitor 2 is much larger than the capacitance of the capacitor 5. As the charge of the capacitor 5, the decreasing current through the inductor 3 causes the appearance of an EMF of self-induction, which charges the capacitor 5 to a voltage greater than the voltage across the capacitor 2, and when the current through the inductor ceases, the voltage key outlet 4 becomes higher than at its input. At the same time, EC 4 closes. The duration of the charging process of the capacitor 5 is determined by the parameters of the oscillatory circuit (its time constant) formed by the inductance of the inductor 3, capacitors 2 and 5 and the inductance of the winding of the ignition coil 7. In the case when the inductance of the inductor 3 is much less than the inductance of the primary winding of the ignition coil 7, the charging time of the second storage capacitor 5 is determined by the time constant τ of the circuit formed by the inductance of the inductor 3 and the capacitance of the series-connected capacitors 2 and 5. This time is calculated by the formula

where L is the inductance of the inductor 3;
C is the capacitance of series-connected capacitors 2 and 5.

 For example, at L = 10 μH and C = 1 μF, τ = 10 μs.

 Breakdown of the spark gap by the high voltage occurring on the secondary winding of the ignition coil 7 occurs 10-15 μs after applying voltage to the primary winding of the ignition coil 7. After the key 4 is closed by the current source for the ignition coil 7, the capacitor 5 becomes charged, an oscillatory process begins in the circuit formed by the capacitor 5 and the primary winding of the ignition coil 7. The voltage across the capacitor 5, passing through the zero and negative values and giving part of the energy to the spark, again becomes positive and starts the one-shot 10, the pulse at the output of which through the element 2 OR 13 generates a logical "0" voltage pulse at the input of the element 2I-NOT 14. The capacitor 9 at this point is again charged with the output current of the element HE 12, at the moment when the voltage on the capacitor 5 during the oscillation process was negative, and at the output of the element HE 12, respectively, positive. In this case, the capacitor 9 is again discharged through the electronic key switch device 8, the output of which is a pulse that opens the EC 4. The capacitor 5 is charged and the process is repeated until there is a logical signal “1” at the signal input of the control device 6. Thus, the capacitor 9 introduced into the circuit of the ignition system, the charging of which occurs after breakdowns of the spark gap, eliminates the possibility of issuing an EC 4 opening pulse from interference during the breakdown of spark gaps due to the absence of a supply voltage of UVEC 8 at this time.

 The ignition system according to the invention has a maximum frequency of sparking in the pulse train due to the absence of pauses in the flow of current through the primary winding of the ignition coil 7, high noise immunity due to the lack of supply voltage of the electronic key switch 8 during breakdown of spark gaps, automatically adapting to any standard the ignition coil, interchangeability with existing ignition systems, as it allows the connection of the windings of the ignition coil to both negative and positive power busbars.

Claims (3)

 1. An ignition system comprising a DC-voltage converter, two storage capacitors, a choke, an electronic key (EC) with a signal and control inputs and one output, an ignition coil, an electronic key control device (UUEK) with two inputs - a signal and a control and the first and the second outputs, the output of the DC / DC converter connected to one terminal of the first storage capacitor and one terminal of the inductor, the second terminal of which is connected to the input of the electronic key, in addition, The output terminal of the second storage capacitor is connected to one terminal of the primary winding of the ignition coil and the control input of the UUEK, the other terminals of the storage capacitors and the common terminal of the DC / DC converter are connected to the negative bus of the power supply (common bus), and the other conclusions of the windings of the ignition coil are connected to the negative or positive power supply buses, characterized in that an electronic key switch device (UVEC) with two inputs and one bipolar output and a capacitor are introduced into it, why one input of the UVEC is connected to the first output of the UUEK, and the other input of UVEC is connected to the second output of the UUEK and one output of the capacitor, the other output of which is connected to the negative bus of the power supply (with a common bus), in addition, one pole of the output of the UVEC is connected to the signal input EC and the second output of the inductor, and the other pole of the UVEC output is connected to the control input of the EC, in addition, the output of the EC is connected to one output of the second storage capacitor, one output of the primary ignition winding and the control input of the UUEK.  2. The ignition system according to claim 1, characterized in that the electronic key control device (UUEK) contains two one-shots, elements 2ILI, 2I-NOT and NOT, and the input of the first one-shot is connected to the signal input of UUEK and one input of the 2I-NOT element, the input of the second one-shot is connected to the output of the EC and the input of the element NOT, in addition, the output of the first one-shot is connected to one input of the element 2 OR, the output of the second one-shot is connected to another input of the element 2 OR, the output of which is connected to another input of the element 2AND, the output of the element 2I- Is NOT is the first output of the UUEK, and the output of the element is NOT the second output of the UUEK.  3. The ignition system according to claim 1, characterized in that the electronic key is made on a thyristor.

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