RU2078246C1 - Electronic ignition system - Google Patents

Abstract

FIELD: transport engineering; electrical equipment of automobiles and power installations with internal combustion engines; fuel ignition systems. SUBSTANCE: electronic ignition system has storage battery, ignition coil, electromechanical breaker and electronic switch consisting of three stages. High or low resistance ignition coil can be used in system. EFFECT: improved reliability of operation. 1 dwg

Description

 The invention relates to electrical equipment of automobiles, in particular to ignition systems of a combustible mixture in internal combustion engines.

 Known electronic ignition system [1] which is based on a thyristor-transistor switch. Such a combined circuit synthesizing the positive properties of transistor and thyristor circuits allows you to get a high-quality spark. However, this system is cumbersome, unreliable and technologically difficult to manufacture.

 Known electronic ignition system [2] in which these disadvantages are eliminated. The system contains a battery, with (+) terminal of which the ignition coil and an electronic switch are connected, which is also connected to the coil. The switch is connected to the contacts of the interrupter-distributor, made in the form of a Hall sensor. A Hall sensor and an electronic switch are connected to the (-) terminal of the battery, which is a series of connected input, intermediate and output stages. The input stage is made in the form of a transistor with corrective chains. The intermediate stage is made on four operational amplifiers with corrective chains. The output stage, made in the form of two transistors with corrective chains and one composite transistor. The system includes a parametric stabilizer based on a powerful zener diode and filtering capacitors. Such a system allows you to create a high slew rate of the high voltage pulse and a long inductive phase of the spark due to the use of operational amplifiers and a special coil.

 The specified technical solution is the closest to the proposed technical essence and the achieved result, in connection with which it is selected as a prototype.

 However, this electronic ignition system creates insufficient conditions for complete combustion of the mixture, i.e. the presence of operational amplifiers does not allow to have a higher slew rate of high-voltage voltage, and the use of a special coil allows this ignition system to be used only on vehicles of certain brands, for example, VAZ-2108, 2109 and ZAZ-1102.

 The proposed electronic ignition system allows you to create conditions for complete combustion of the mixture and use the system not only on vehicles, but also on power plants with internal combustion engines (carburetor, injection, rotary piston).

 This solution of the proposed electronic ignition system allows you to create a guaranteed synchronization of the high voltage pulse in the internal combustion engine with the position of the crankshaft or rotor in time. The use of high-speed logic provides a high slew rate of the high-voltage pulse and the ability to switch the set current through the ignition coil by the output stage, i.e. to obtain the specified duration of the inductive phase of the high-voltage discharge in the internal combustion engine, thus creating the conditions for complete combustion of the mixture. The proposed ignition system allows the use of an electronic switch with a low-resistance or with a high-voltage ignition coil both on vehicles and on power plants with internal combustion engines.

 The drawing shows a circuit diagram of an electronic ignition system.

 The electronic ignition system comprises a storage battery 1, with a (+) terminal of which an ignition coil 2 and (+) an electronic switch bus are connected, comprising output A, intermediate B and output C of the cascade in series. The switch is also connected to the ignition coil 2. The output of the contacts of the breaker-distributor 3 is connected to the input of the input stage A. The contacts of the breaker-distributor 3 and (-) the switch bus are connected to the (-) terminal of the battery 1.

 The input stage A is made in the form of a current source containing a transistor (P-n-P) 4 and a resistor 5 for setting the current value of the transistor 4. The emitter of the transistor 4 is connected to the (+) switch bus. One of the contacts of the interrupter-distributor 3 is connected to a chain of light indications of its state, including LED 6, diode 7 for protection against reverse voltage, limiting the current of LED 6 resistor 8.

 The chain is connected to the output of a parametric voltage stabilizer, which is a zener diode 9 connected in series and a resistor 10 limiting the current through it. The latter is connected to the switch (+) bus, and the stabilizer 9 to the (-) bus. Their common point a is connected to the base of transistor 11 for transmitting voltage and amplifying current to the emitter of transistor 11 n-p-n, the collector of which is connected to the (+) bus of the switch. A capacitor 12 and an electrolytic capacitor 13 are connected in parallel to the emitter of the transistor 11 and to the (-) bus of the switch in order to filter the voltage. A capacitor 14 is connected between the busbars of the switch, which is a filter at the input of a parametric voltage stabilizer. The input of the light indication chain is connected to the input of the input pulse voltage limiter, which is made in the form of a series-connected zener diode 15 connected to the (-) bus of the switch and the current limiting resistor 16 connected to the input of the light indication chain. Their common point b, is the output of the input pulse voltage limiter, connected to an integrating circuit. It includes an integrating capacitor 17, one output connected to the (-) bus of the switch, and the other to resistors 18 and 19, limiting the charging current and discharge current of the capacitor 17 and diode 20, respectively, preventing the discharge of the capacitor 17 through the resistor 18.

 The common point with resistors 18, 19 and capacitor 17 is the output of the integrating circuit. The second resistor 19 is connected to the (-) bus of the switch, and the second resistor 18 is connected to the (-) terminal of the diode 20, the additional output of which is connected to the output of the input pulse voltage limiter, i.e., to the common point b of the zener diode 15 and resistor 16 The output of the integrating circuit c is connected to the base of the emitter follower, consisting of a transistor npn 21 and a resistor 22.

 The collector of the transistor 21 is connected to the output of the voltage stabilizer, the emitter of the transistor 21 to the resistor 22, the second output of which is connected to the (-) bus of the switch. The common point d of the connection of the emitter of the transistor 21 and the resistor 22 is the output of the emitter follower, which is connected to the input of the Schmitt trigger, built on the basis of two logical elements 2 AND 23 and 24 and two resistances 25 and 26.

 The output of the Schmitt trigger is connected to an intermediate stage B, which is made in the form of two series-connected logic elements 2I-NOT 27 and 28. All the logic elements and the logic element 29 of the incoming current are connected on the power supply to the voltage regulator, and on the other hand to ( -) to the switch bus.

 The output stage C is an incoming current made as a logic element 29, pnp transistors 30, and npn 31 transistor according to an additional switching circuit, resistors 32, 33, limiting the base currents of transistors 30, 31, resistors 34, 35 to create a certain potential at the bases of transistors 31, 31, respectively, and an output pulse voltage limiter consisting of a resistor 36 and a zener diode 37. To the output of the intermediate stage B is connected the input of the incoming current logic element 29, and its output to the resistor 32 connected th to the base of transistor 30 and resistor 34. The emitter of transistor 30 and a second terminal of the resistor 34 is connected to (+) bus switch. The collector of transistor 30 is connected to a resistor 30, the second terminal of which is connected to the base of transistor 31 and resistors 35. The emitter of transistor 31 and the second terminal of resistor 35 are connected to the (-) bus of the switch. The collector of the transistor 31 is connected to the coil 2 and the ignition and to a series-connected resistor 36 and a zener diode 37, the second terminal of which is connected to the (-) bus of the switch, connected to the (-) terminal of the battery 1, (+) the bus of the switch is connected to (+) the battery terminal and to the (+) terminal of the ignition coil 2 (when using a low resistance coil through a ballast resistor).

 The device operates as follows.

 With the closed contacts of the fuse-distributor 3, the current from the (+) terminal of the battery 1 through the (+) bus of the switch, transistor 4 and resistor 5, through the closed contacts of the fuse-distributor 3 are fed to the (-) terminal of the battery 1. The integrating capacitor 17 is charged to the voltage of the input pulse limiter, they begin to discharge through the resistor 19 and the base-emitter junction of the transistor 21 and the resistor 22. The diode 20 prevents the discharge of the capacitor 17 through the resistor 18. As the capacitor 17 is discharged, the transistor 21 s sticks. Schmitt trigger switches from state "1" to state "0". Logic element 27 switches to state "1", and logic element 28 to state "0". The incoming current logic 29 is switched from the state “1” to the state “0”. Transistors 31, 31 open and current flows from the (+) terminal of battery 1 through the primary winding of the ignition coil 2, transistor 31, (-) switch bus to (-) battery terminal 1. The primary winding of the ignition coil 2 enters the application by current, stores inductive energy.

 The current flows from the output of the transistor 11, through the resistor 8, diode 7, LED 6, the closed contact of the distributor 3, causing the LED 6 to glow and giving information about the electrically closed state of the contact of the distributor 3.

 When the breaker-distributor 3 contacts open, the current from the (+) battery terminal 1 through the (+) switch bus, transistor 4, resistors 5, 16 and the zener diode 15 enters through the (-) switch bus to the (-) battery terminal 1. Integrating the capacitor 17 begins to be charged in a chain: the output of the input pulse voltage limiter (common point b), diode 20, resistor 18, capacitor 17, (-) the battery terminal. As the capacitor 17 charges, transistor 21 opens. Schmitt trigger switches from state "0" to state "1". Logic element 27 switches to state "0", and logic element 28 to state "1". The incoming current logic 29 is switched from the state “0” to the state. The transistor 30, 31 switches to cutoff mode. The current in the primary winding of the ignition coil 2 begins to decrease at a certain speed and a high voltage pulse with a certain slew rate is formed in the primary winding of the ignition coil 2, which is transformed by the ignition coil 2 into a secondary winding (into a high voltage pulse).

 When the contacts of the interrupter-distributor 3 open, the LED 6 ceases to glow, that is, the current does not flow through the light indication chain. LED 6 and diode 7 are locked by the high potential of battery 1.

 The current source 4, 5 sets the current through the contacts of the breaker-distributor 3 (by selecting a resistor 5), creating the conditions of an electrically guaranteed contact during mechanical closure of the contacts of the breaker-distributor 3 and their minimal wear (the process of electrical self-cleaning of the contact surfaces occurs).

 The voltage limiter 15, 16 provides a constant voltage at the output to stabilize the parameters of the integrating circuit (i.e., the charge and discharge time of the integrating capacitance 17), thereby eliminating the influence of the voltage of the battery 1 (on-board network) on the output pulse parameters. An integrating chain is necessary to integrate the input and output edge of the input pulse and, together with the Schmitt trigger, eliminates the false triggering of the input stage A, providing electrical parameters of the pulse at its output, independent of the voltage of the battery 1, ambient temperature (thermostable capacitor 17 is used), speed the crankshaft and the technical condition of the contacts of the interrupter-distributor 3 and the distributor itself. The coordination of the capacitor 17 of the integrating chain 18, 19, 20 with a Schmitt trigger, the parameters of which are set by its resistors 25, 26, is carried out through the emitter follower 21, 22.

 The light indication chain 6 8 allows, if necessary, to control the operation of the contacts of the interrupter-distributor 3 and the initial ignition timing of the engine, adjusting it if necessary.

 This embodiment of the output stage allows the transistor 31 to have a minimum saturation voltage, i.e. minimal losses, and therefore, maximum transfer of electrical energy to the ignition coil 2, and connect to any low-resistance or high-resistance ignition coil when using typical transistors.

 Logic elements 27, 28 "sharpen" the front and the fall of the pulse. The selection of the resistor 32 sets the minimum saturation voltage of the transistor 31 with the closed contacts of the chopper-distributor 3.

 The limitation of the high voltage level in the primary winding of the ignition coil 2 is determined by the resistor 33 and the applied zener diode 34.

 When changing the voltage of the battery 1 (on-board network), the parametric stabilizer 9-14 (the level of its supply voltage is determined by the parameters of the zener diode 9) provides a constant voltage to the input stage A, the light indication chain 6 8 and the logic elements 23, 24, 27, 28, 29.

Using the proposed ignition system allows you to:
by providing the ability to create conditions for complete combustion of fuel in the internal combustion engine, significantly reduce its consumption. So, when using the system on a Moskvich-2141 car with an Ufa engine (mileage of 8,000 km, loading above the nominal) on a 1000 km highway at a speed of 100 km / h, fuel consumption was 6.4 liters per 100 km;
use various grades of gasoline and their mixtures;
to ensure the normal operation of the internal combustion engine with an optimal ignition timing;
sharply reduce the emission of harmful substances into the atmosphere;
operate the engine in normal mode at temperatures above 30 ^o C (due to the high slew rate of the high-voltage pulse, the onset of combustion of the mixture is accelerated). So, in a car of the RAF brand, at full load, even in the hottest weather, overheating was not observed, although before the installation of the system in the summer there was always a constant overheating of the engine;
normal operation of the engine with its transient modes;
to carry out "easy" engine start under any conditions;
eliminate the problem of spark plugs and high-voltage wires, which is explained by the high slew rate of the high-voltage pulse, at which voltage "leakage" does not affect the quality of the spark (you can continue to operate the "old" high-voltage wires and candles with an increased gap);
eliminate the need to adjust the system (contact wear is minimal due to the operation of the input stage of the switch);
increase the life of the engine oil, resulting in significantly increased engine life (due to complete combustion of the fuel, the amount of exhaust substances in the combustion chamber decreases, the amount of exhaust substances in the oil system also decreases);
operate the engine in optimal mode under various climatic conditions;
use both low-resistance and high-resistance ignition coils.

 The proposed electronic ignition system, which creates the conditions for complete combustion of the mixture, allows the system to be used not only in vehicles, but also in power plants with internal combustion engines (carburetor, injection, rotary piston).

Claims (1)

 An electronic ignition system comprising a battery, the first terminal of which is connected to a common bus, the second to the input of a voltage regulator, to the first input of the power supply of the electronic switch and to the first terminal of the primary winding of the ignition coil, the second terminal of which is connected to the output of the electronic switch, and a chopper the fact that the breaker is electromechanical and a light indication circuit and a current generator are introduced into the system, the first output of which is connected to the second output of the battery, the second with the first output of the light indication chain, with the first output of the chopper, the second output of which is connected to the common bus, and with the input of the electronic switch, the second power input of which is connected to the output of the stabilizer and with the second output of the light indication, while the electronic switch consists of a limiter voltage of the input pulse, the input of which is connected to the input of the electronic switch, the output through a series-connected resistive-capacitive circuit, an emitter follower, a Schmitt trigger with input output cascade of the electronic switch, the input of which is connected through the shaper of the incoming current to the output shaper made on complementary bipolar transistors with an unsaturated washing transistor, the collector of which is connected to the damping circuit and to the output of the electronic switch.