RU2276282C2 - Ignition system of internal combustion engine - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines.

SUBSTANCE: invention relates to devices for adjusting spark discharge parameters and it can be used both in high-energy ignition system and in standard battery-fed ignition system. Proposed ignition system of internal combustion engine contains supply source and ignition coil, first leads of primary winding of ignition coil being connected to output terminal of supply source, and second lead, to first output terminal of capacitance element, and also distributor, spark plugs, control signal shaper and electronic switch. System is furnished additionally with breaker, feedback signal shaper and logic 1 NOR gate. Supply source has two additional output terminals, first of which is connected with minus terminal of supply source through electronic switch and second one, together with first output of feedback signal shaper, with input of control signal shaper and first output of breaker. Second output of breaker is connected with minus terminal of supply source, and with point of connection of second lead of ignition coil primary winding and first output of capacitance element. Second output of capacitance element is connected to minus terminal of supply source. First input of 2 NOR gate is connected with second output of feedback signal shaper, and its second input, with output of control signal shaper, and its output, with control input of electronic switch.

EFFECT: improved ignition system of internal combustion engine, increased efficiency, reliability quick response and economy, simplified system.

6 cl, 3 dwg

Description

The invention relates to engine building, in particular to ignition systems of an internal combustion engine, and in particular to devices for controlling spark discharge parameters, and can be used in conjunction with both a high energy ignition system and a classic battery ignition system.

A known method of ignition of a fuel-air mixture and an ignition system for its implementation, according to which the fuel-air mixture is ignited by applying high-frequency voltage pulses to electrodes connected to the secondary winding of the ignition coil, the frequency of the voltage pulses changing depending on the magnitude of the current in the secondary winding of the coil ignition, and the ignition system contains a current source and the primary winding of the ignition coil and an electronic key connected to it in series to the control input which is connected in series with the ignition timing signal generator and a pulse generator, whose frequency control input is connected through the current feedback signal generator in the ignition coil to the connection point of the primary winding of the ignition coil and the electronic key (see RF patent No. 20044835, publ. 15.12.1993 )

The disadvantage of this method and device is that they do not provide sufficiently complete combustion of the fuel and reduce the level of toxicity of combustion products due to the low frequency and energy of sparking. The frequency of spark repetition is limited by the need to provide sufficient time for each pulse generator to accumulate energy in the primary winding of the ignition coil, and the energy of sparking is reduced due to the insufficient frequency of repetition of sparks, pauses between sparks and the use of negative half-waves of voltage on the primary winding of the ignition coil.

The ICE ignition system is also known, which contains a power source with a storage battery, an ignition key, a step-up voltage converter and a capacitive storage, an ignition coil with capacitive elements connected in parallel to its primary winding, a distributor and spark plugs, as well as a control signal shaper, a series forming unit pulses with a single vibrator, an oscillator and a frequency-voltage converter and an electronic key. This system provides a more complete combustion of fuel and reduction of toxicity of exhaust gases due to the higher energy and frequency of sparks of ignition of alternating current (see RF patent No. 2069791, publ. 11/27/1996). This system is closest to the claimed in technical essence and adopted as a prototype.

The disadvantages of the system are:

- insufficiently complete combustion of the fuel and high toxicity of exhaust gases due to the lack of automatic correction of the frequency of the ignition pulses during the combustion of the fuel-air mixture;

- low reliability, as when installing the system on a car, a complete alteration of the standard system is required and returning to it in case of failure of the proposed system requires considerable effort and a certain level of skill;

- the complexity determined by the presence of a special unit for generating a series of pulses with a single vibrator, a self-oscillator and a frequency-voltage converter and the implementation of an adjustable voltage boost converter;

- low speed forced correction of a series of sparks due to the presence of a frequency-voltage converter in the control channels;

- high energy consumption, due to the fact that the system not only supports the oscillatory process in the ignition coil with a capacitive element, but should also initiate the first breakdown of the interelectrode gap in the candles in each series, and since the ignition coil operates in direct transformation modes as in normal a thyristor ignition system, a step-up voltage converter must have a large output voltage (at least 300 V) and, therefore, has a low efficiency;

- the complexity of the adjustment associated with the need to accurately set the frequency of the oscillator;

- excessive erosion of candles and a high level of electromagnetic interference due to the unipolar nature of the current in the spark plugs and a high level of capacitive components of the discharge, which cannot be reduced by the prototype system without reducing the sparking energy due to the fast attenuation of inductive components located in the pauses between the capacitive components.

The basis of the invention is the task of improving the ignition system of the internal engine by feeding the oscillatory circuit formed by the capacitive element and the ignition coil from the step-up voltage converter during negative half-waves of voltage, to provide a high frequency of sparks and sparking energy during automatic correction of the frequency of ignition pulses during the combustion of fuel air mixture, increased speed, reduced electromagnetic interference, reduced candle erosion th and, as a result, the creation of an effective, reliable, simple, fast-acting, economical, not requiring adjustment of the engine ignition system, which provides more complete combustion of the fuel and a decrease in the level of toxicity of combustion products.

The problem is solved in that in a known ignition system of an internal combustion engine containing a power source and an ignition coil, the first output of the primary winding of which is connected to the output of the power source, and the second to the first output of the capacitive element, distributor, spark plugs, driver of control signals and an electronic key, according to the claimed invention, an additional chopper, a shaper of the feedback signal and a logic element 2OR-NOT are introduced into the system, moreover, the power supply is equipped with two additional outputs, the first of which is connected to the minus of the power source via an electronic key, and the second, together with the first output of the feedback signal shaper, is connected to the input of the control signal shaper and the first output of the chopper, the second terminal of which is connected to the minus of the power source, to the connection point of the second the output of the primary winding of the ignition coil and the first output of the capacitive element, the second output of which is connected to the minus of the power source, the first input of element 2 is NOT connected to the second output ohm of the feedback signal driver, its second input is with the output of the driver of the control signals, and its output is with the control input of the electronic key.

The power source can be made with three inputs in the form of a series-connected battery, ignition key and step-up voltage converter with a capacitive energy storage device, with the minus of the battery being a minus of the power source, the connection point of the ignition key and the input of the step-up voltage converter forms the output of the power source, outputs the boost converter is galvanically disconnected from the battery, its positive output forms the first additional output of the power source, and negative - the second additional output of the power source.

The feedback signal generator can be made, for example, in the form of a resistor and a capacitor connected in series. The driver of the control signals may contain a series-connected device for suppressing the "bounce" of the contacts of the chopper and a device for angularly limiting the duration of the spark discharge.

The device for suppressing the "bounce" of contacts of the interrupter may contain a logic element NOT, the input of which is connected through the first resistor to the input terminal of the device, and its output is connected through the return diode to the output terminal of the device, also connected through the second resistor to the output of the power source, and through the capacitor - with minus the power source.

The device for the angular limitation of the duration of the spark discharge may contain an RS-flip-flop made on two logical elements 2I-NOT, the installation input of which is connected through the first capacitor to the input output of the device and through the first resistor to the output of the power source, and its reset input to the output of the operating amplifier and through the second capacitor with the inverting input of the operational amplifier, which is also connected through a chain consisting of a series-connected reverse first diode and a second resistor, a pair allel is connected chain of consecutive direct diode and the third resistor, to the inverting output RS-flip-flop, the non-inverting output of which is the output device and the non-inverting input of the operational amplifier is supplied the bias voltage.

Figure 1 shows the functional diagram of the ignition system of the internal combustion engine.

Figure 2 - schematic diagram of the formation of control signals of the ignition system.

Figure 3 - plot voltage, explaining the operation of the shaper control signals, where:

A is the state of the contacts of the chopper at the input of the driver of the control signals and at the input of the device for suppressing "bounce" of contacts;

B - the voltage at the output of the logic element is NOT a device for suppressing "bounce" of contacts;

B - voltage at the output of the device for suppressing “bounce” of contacts;

G - signals at the output of the RS-trigger device;

D is the signal at the inverting output of the RS-trigger;

E is the voltage at the reset input of the RS-trigger;

G - signal at the output of the driver of control signals.

The ignition system (Fig. 1) contains a power source 1 with three outputs, an ignition coil 2 with primary 3 and secondary 4 windings, a distributor 5 of the ignition, spark plugs 6, an electronic key 7, a logic element 8 2 or NOT, a driver 9 feedback signal , capacitive element 10, chopper 11 and driver 12 of the control signals. The output of the power source 1 is connected to the first output of the primary winding 3 of the ignition coil 2, its first additional output is connected via an electronic key 7, the control input of which is connected to the output of the element 8 2 OR NOT, with the minus of the power source.

The second additional output of the power supply 1 is connected to the second output of the primary winding 3 of the ignition coil 2 directly, with the minus of the power supply 1 through the parallel capacitive element 10 and the chopper 11, with the first input of the element 8 2 OR NOT via the former 9 and with the second input of the element 8 2 OR -NOT - through the shaper 12. In the ignition system, the power source 1 contains a battery 13 connected in series, the minus of which is the minus of the power source 1, the ignition key 14 and the boost converter 15 are voltage tions with a capacitive energy store 16 and electrically isolated from the battery. The connection point of the ignition key 14 and the input of the converter 16 forms the output of the power source 1, the positive output of the converter 15 forms the first additional output of the power source 1, and the negative output forms the second additional output of the power source 1.

The generator 12 of the control signals of the ignition system contains a series-connected device 17 for suppressing "bounce" of the contacts of the chopper and the device 18 of the angular limitation of the duration of the spark discharge.

In the process of operation of the ignition system (Fig. 2), the high-frequency oscillatory process of sparking begins after the contacts of the interrupter 11 open. In this case, the former 12 sets a signal of a low logic level at the second input of the element 2 2 OR NOT for the period of time that determines the duration of the packet of sparks in each sparking cycle. The feedback signal during the negative half-wave voltage on the winding 3 of the ignition coil 2 is supplied through the driver 9 to the first input of the element 2 2 OR NOT, after which the electronic key 7 is opened.

The capacitor 16 of the power source 1, charged to an increasing voltage (more than 100 V), is turned on in series with the battery 13 and the winding 3 of the ignition coil 2. This total voltage recharges the capacitor 10 and forces the reverse current in the winding 3 of the coil 2. The oscillation circuit formed by the capacitor 10 and the coil 2 is energized, as a result of which the current in the winding 3 in the forward direction increases significantly in comparison with the values that occur in in case of attenuation of oscillations in the circuit without recharge. When the negative half-wave of voltage on the winding 3 passes through a zero value and becomes positive, a low logic level signal appears at the output of the driver 9, and the key 8 closes, interrupting the current in the forward direction through the winding 3. Next, the oscillatory undamped process is repeated for the length of time when the driver 12 maintains a low logic signal at the other input of element 8.

Shaper 12 of the control signals (Fig.2) ignition contains a series-connected device 17 for suppressing "bounce" of the contacts of the chopper and the device 18 of the angular limitation of the duration of the spark discharge. During the opening of the contacts of the chopper 11 at the input of the element 20 does NOT appear a signal of a high logical level (Fig.3A), and at its output - low (Fig.3B). The capacitor 23 is discharged through the diode 21 and the output of the element 20 (Fig.3.V).

In the event of a "bounce" of the contacts of the chopper 11, the capacitor 23 is discharged when the first signal of a low logic level appears at the output of the element 20. The delay in the charge of the capacitor 23 due to the presence of the resistor 22 in its charge circuit maintains the capacitor 23 in the discharged state during the "bounce" contacts and when they are closed.

The chain R26 C25 differentiates the voltage across the capacitor 23 (Fig.3.V) and generates short installation signals at the input of the RS-flip-flop 24 (Fig.3.G). At the inverting output of the trigger 24 appears a signal of a high logical level (Fig.3.D), at its inverting output and the output of the former 12 - low (Fig.3.Zh). The voltage at the output of the operational amplifier 27, included in the integrator circuit, decreases linearly to the reset level of the trigger 24 (Fig.3.E), after which it switches again (Fig.3.E). The signals at its outputs are reversed (Fig.3.D, G), and the voltage at the output of the amplifier 27 increases linearly until the next installation signal. The process is then repeated. Due to the choice of asymmetry, the charge chain (diode 29, resistor 30) and discharge (diode 31, resistor 32) of the capacitor 28, you can set any angular duration of the output signal of a low logic level at the output of the shaper 12 in the range from 0 to 45 ° rotation angle of the distributor 5, which supported with high accuracy over a wide range of speeds.

The system provides more complete combustion of the fuel and reduction of toxicity of exhaust gases due to the automatic setting of the frequency of the ignition pulses depending on changes in the parameters of the fuel-air mixture during its combustion. As a result of the interaction of the fuel plasma, which burns in the electromagnetic field around the electrodes of the spark plugs, the frequency characteristics of the ignition coil windings and, accordingly, the resonant frequency of the oscillatory circuit formed by the inductance of the primary winding of the ignition coil and the secondary and capacitive element brought to it, change.

The system does not provide for a rigid setting of the oscillation frequency, but organizes undamped self-oscillations in the oscillatory circuit, the inductance of which is directly corrected by the combustion process of the fuel-air mixture.

The ignition system increases the reliability of the engine system, as for its installation is not provided for the dismantling of the standard ignition system, and it is fully preserved.

The system is connected to the standard using 4 wires, while in the standard system you need to make only one disconnect. Therefore, in case of failure of the proposed system, it will be duplicated by a regular system, which will not be difficult to remake.

The proposed ignition system is much simpler than the prototype device, since its circuit does not contain a pulse train forming unit containing a single vibrator, a self-oscillator and a frequency-voltage converter, instead of which three simple elements are introduced: an electronic key (or chopper), a feedback signal shaper, and logic element 2 OR NOT. In addition, further simplification is achieved by making the step-up voltage converter unregulated, since its power is low.

The speed of the proposed system is significantly increased, because the speed of frequency correction is set only by the speed of change in plasma concentration near the electrodes of the candles, and the frequency-voltage converter is absent.

The ignition system requires significantly less energy, because the energy of the step-up voltage converter is not spent on the initiation of the primary breakdown, but is spent only on maintaining self-oscillations. Since the phase of the energy pumping pulses in the oscillatory circuit is set automatically, an error in the phase is excluded and there is no need to create an energy reserve in case of a phase “escape” or an error of forced frequency setting, as in the prototype device. In addition, since the increased voltage in the proposed system is significantly reduced (no more than 100 V), the efficiency of the boost converter is greater, and the energy consumption is less. The system does not require any initial frequency adjustment, since Frequency of multiple sparking is set automatically automatically.

In the proposed system, the erosion of candles and the level of electromagnetic interference are significantly reduced, because not pulsed unipolar, but alternating current flows between the electrodes of the candles, and the capacitive component of the spark discharge current in each packet of sparks is present in its pure form only during the first spark.

These characteristics are unknown to the authors from domestic and foreign sources, therefore they are significant and new. The proposed solution does not explicitly follow from the current level of technology and is not obvious to experts in the field of automotive electronics. The solution can be implemented by known means of production. Therefore, it meets the criteria of the invention and may be given legal protection.

Claims (6)

1. The ignition system of an internal combustion engine containing a power source and an ignition coil, the first output of the primary winding of which is connected to the output of the power source, and the second to the first output of the capacitive element, distributor, spark plugs, driver of control signals and an electronic key, characterized in that an additional chopper, a shaper of the feedback signal and a logic element 2 OR are NOT introduced into it; moreover, the power supply is equipped with two additional outputs, of which the first is connected to the inus of the power source through an electronic key, and the second together with the first output of the feedback signal shaper - with the input of the driver of the control signals and the first output of the chopper, the second output of which is connected to the minus of the power source, with the connection point of the second terminal of the primary winding of the ignition coil and the first output of the capacitive element, the second output of which is connected to the minus of the power source, the first input of element 2 OR is NOT connected to the second output of the feedback driver, its second input is connected to the control signal generator, and its output - with the control input of the electronic key. 2. The system according to claim 1, characterized in that the power source is made with three inputs in the form of a series-connected battery, an ignition key and a step-up voltage converter with a capacitive energy storage device, wherein the minus of the battery is a minus of the power source, the connection point of the ignition key and the input of the step-up voltage converter forms the output of the power source, the outputs of the step-up converter are galvanically disconnected from the battery, its positive output there is the first additional output of the power source, and negative - the second additional output of the power source. 3. The system according to claim 1 or 2, characterized in that the driver of the feedback signal is made, for example, in the form of a resistor and a capacitor connected in series. 4. The system according to claim 2, characterized in that the driver of the control signals comprises a serially connected device for suppressing "bounce" of the interrupter contacts and a device for angularly limiting the duration of the spark discharge. 5. The system according to claim 4, characterized in that the device for suppressing the "bounce" of the breaker contacts contains a logic element NOT, the input of which is connected through the first resistor to the input terminal of the device, and its output is connected through the return diode to the output terminal of the device, also connected through the second resistor to the output of the power source, and through the capacitor to the minus of the power source. 6. The system according to claim 5, characterized in that the angular device for limiting the duration of the spark discharge contains an RS-flip-flop made on two logic elements 2I - NOT, the installation input of which is connected through the first capacitor to the input terminal of the device and through the first resistor to the output power supply, and its reset input - with the output of the operational amplifier and through a second capacitor with an inverting input of the operational amplifier, which is also connected through a chain consisting of the inverse of the first an iodine and a second resistor, in parallel with which a chain of consecutive direct diodes and a third resistor is connected, with an inverting output of the RS-trigger, the non-inverting output of which is the output of the device, and a bias voltage is applied to the non-inverting input of the operational amplifier.

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