RU2065074C1 - Device for ignition system of internal combustion system - Google Patents

Abstract

FIELD: automobile electrical equipment; forced ignition internal combustion engines. SUBSTANCE: device has electronic interrupter 2 and monolithic integrated circuit, type KP1047 KT1, second input 16 for connecting the second sensor, resistor 12 of operating current of the second sensor, input shaper 11 with open output which consists of time-setting network and inverter 48 connected in series. Operating correction device Y3 and switch of anti-theft device or both may be connected between output of shaper 11 and first input 42 of monolithic integrated circuit 7. EFFECT: enhanced reliability. 4 cl, 4 dwg

Description

 The invention relates to electrical equipment of automobiles, in particular, to ignition systems of internal combustion engines (ICE) with forced ignition of the fuel-air mixture in the combustion chambers of piston engines.

Known devices for ignition systems of internal combustion engines containing an input driver and a switching transistor controlling the operation of the ignition coil. These devices are controlled both by the contacts of the ignition distributor breaker [1] and by the proximity sensor [2]
The current limitation in the primary winding of the ignition coil is ensured by the added resistance connected in series with the primary winding of the ignition coil. In start mode, the additional resistance is shorted.

 Despite its simplicity, the device has several significant drawbacks. This is a large power dissipation in the coil and additional resistance, low output characteristics of the ignition system.

 A device [3] is known that eliminates these disadvantages due to the presence in it of means for actively limiting the output current, adaptively turning off the output current when the engine is stopped.

 The disadvantage of this device is complexity.

 The closest in technical essence is a device [4] containing a switching transistor and a monolithic integrated circuit with the functions of limiting the output current, adaptive regulation of the duty cycle of the output current pulses and smooth switching off of the output current when the engine is stopped.

 The disadvantage of this device is the narrow scope due to the possibility of using only one type of sensor.

 The present invention allows to expand the scope of the device.

 A positive effect in the industrial production of the device according to the invention is to reduce the cost of the product by reducing the number of components, block sizes, printed circuit boards, etc.

 A positive effect is also an increase in the reliability of the product, especially when it is manufactured using SMD technology or hybrid integrated technology on thick films.

 Due to this, it is possible to operate, for example, the B115 ignition coil without additional resistance, while simultaneously reducing its overheating in the dissipated power, i.e., thereby increasing the life of the ignition coil.

 A positive effect from the application of a technical solution can be achieved by improving the characteristics and parameters of ignition devices, which favorably affects the operation of the internal combustion engine.

 For this, in a device for an internal combustion engine ignition system containing an electronic chopper and a monolithic integrated circuit with the features of a prototype, a second input is provided for connecting a second crankshaft angular position sensor (UPCW), a working current resistor of the second sensor, an open shaper input shaper that contains in series included timing circuit and inverter, the output of the former being connected to the first input of the integrated circuit.

 Between the output of the input shaper and the first input of the monolithic integrated circuit, either an online ignition timing (MH) device, or an anti-theft device switch, or both can be included.

 Using these tools, a device is realized that has new properties that are not manifested in known technical solutions.

 According to the invention, the authors have a working prototype and a positive test report.

 In FIG. 1 shows an embodiment of a device for an engine ignition system; in FIG. 2 and 3 embodiments of the device for the engine ignition system, taking into account special cases; in FIG. 4 diagrams explaining the principle of operation of the device in FIG. 1.

 The circuit of the device for the internal combustion engine ignition system (see Fig. 1) contains an electronic chopper 2, means 3 for measuring the output current of the device 1, an operating part containing a monolithic integrated circuit 4, time-varying capacitors 5, 6, 7, resistor 8, and a resistor 9 connected in series and a capacitor 10 of the corrective RC circuit, the input driver 11 and the resistor 12.

The device 1 is equipped with terminals 13 (+ U _n ) and 14 (- U _n ) for connecting the positive and negative poles of a DC voltage source, such as a battery, terminal 15 (KZ) for connecting an ignition coil, terminal 16 (Pr) for connecting a sensor UPKV engine, for example, the contacts of the chopper of the classic distributor of ignition, terminal 17 (SE), which is the input of a monolithic integrated circuit 4 and terminal 18 (Ф), which is the output of the input shaper 11, and the conclusions 18 and 17 are interconnected by a bus 19.

 Electronic chopper 2 carries out current switching in the primary winding of the ignition coil. When the electronic chopper 2 is turned on, current flows through the primary winding of the ignition coil, i.e., the process of energy storage in the electromagnetic field of the ignition coil occurs. At the moment of switching off the electronic chopper 2, the accumulated energy is realized in the spark gap of the spark plug. As an electronic chopper 2, for example, a single-chip composite n-p-n transistor KT 898A, made according to the Darlington circuit, is used. The collector terminal 20 of the transistor is connected to the output terminal 15 (KZ) of the device 1. The base terminal 21 of the transistor is connected to the output terminal of the monolithic integrated circuit 4. The emitter terminal 22 of the transistor is connected to the output current measuring means 3, for example, a low-resistance resistor 23 nominal 0.04 0.1 Ohm. A voltage proportional to the output current is removed from the resistor 23 using a voltage divider on the resistors 24 and 25 and is fed to the sensitive input of the monolithic integrated circuit 4.

 The dividing factor of the divider determines the level of limitation of the output current and is set during the manufacture of device 1 during the setup process by changing the resistance of the resistors 24, 25.

 The operational part of the device 1 provides adaptive regulation of the duty cycle of the pulses of the output current, limitation of the output current at a given level, as well as smooth switching off of the output current when the engine is stopped. As a monolithic integrated circuit 4, for example, a domestic linear microchip KR1047KT1 is used, including means 26 for adaptively adjusting the duty cycle of the output current pulses, means 27 for limiting the output current, means 28 for smoothly switching off the output current when the engine is stopped, the output stage 29, and the power supply 30. V in turn, the adaptive duty cycle controller 26 of the output current pulses includes a normalizing integrator 31, a correction integrator 32, and a comparator 33.

, где Z - число цилиндров двигателя.The monolithic integrated circuit 4 contains at least 9 pins for connecting the supply voltage, elements of the operating part of the device 1, and also contains input and output pins. Pins 34 and 35 are used to connect the microcircuit to the positive and negative poles of the DC voltage source, respectively. Pin 36 is used to connect the timing capacitor 5 to the normalizing integrator 31. Pin 37 is used to connect the timing capacitor 6 to the correction integrator 32. Pin 38 is used to connect the timing capacitor 7 to the means 28 for smoothly switching off the output current when the motor is stopped. The terminal 39 connected to the input of the output current limiting means 27 is a sensitive input of the microcircuit 4 and is used to connect the voltage divider 24 and 25 of the output current measuring means 3 to the midpoint of the voltage divider. The output 40, connected to the output of the output stage 29, is the output of the microcircuit 4, is used to directly connect to the base terminal 31 of the switching transistor of the electronic chopper 2. An RC circuit consisting of a resistor 9 and a capacitor 10 connected between the terminals 39 and 40 of the microcircuit 4, corrects the amplitude-frequency and phase-frequency characteristics of the means 27 for limiting the output current and eliminates spurious generation of the switching transistor of the electronic chopper 2 in the mode of limiting the output ka. Pin 41 is used to connect to the output stage 29 of the resistor 8 connected to the positive pole of the DC voltage source. The resistor 8 limits the operating current of the output stage 29. The output 42, connected to the input of the adaptive duty cycle controller 26 of the output current pulses, is the input of the microcircuit 4 and is used to connect a motor VPC sensor, for example, a Hall effect sensor. Any other means generating a square wave signal and satisfying the following conditions can be used as a sensor: an open output, a signal pulse cutoff corresponds to the moment of sparking in the engine spark plug, a low signal level does not exceed 0.4 V, the signal repetition rate is related to the engine speed n expression

where Z is the number of engine cylinders.

 As a monolithic integrated circuit 1, other types of microcircuit can be used, for example, L497, SGS-ТНOMSON, μA 7355, FA1RCH1LД, etc.

 The input driver 11 matches the signal of the second sensor of the UPCV engine, for example, the contacts of the chopper with the input 42 of the chip 4.

 The input driver 11 comprises a series-connected time-setting chain 43 and an inverter 44 with an open output. The timing chain 43, made, for example, in the form of an integrating circuit containing a diode 45, a capacitor 46, a resistor 47, provides protection against contact bounce of the interrupter. Moreover, the cathode of the diode 45, one of the terminals of the capacitor 46 and the resistor 47 are connected to each other, the other terminal of the capacitor 46 is connected to the negative pole of the DC voltage source, the other terminal of the resistor 47 is connected to the input of the inverter 44, and the anode terminal of the diode 45, which is the input of the timing circuit 43 and the input driver 11 is connected to the terminal 16 of the device 1.

 The inverter 44 is made, for example, on an npn transistor 48 with an open collector output, the emitter of which is connected to the negative pole of the DC voltage source, and the base terminal, which is the input of the inverter 44, is connected to the resistor 47, and a resistor 49 is connected between the base and the emitter of the transistor 48 .

 A resistor 12 connected between the positive pole (terminal 13) of the DC voltage source and input 16 of the device 1 provides the operating current of the second sensor, for example, the current through the contacts of the chopper.

 The diagram of the device 1 of the ignition system for ICE in FIG. 2 is characterized in that between the output of the input driver 11 (output 18) and the input 42 of the microcircuit 4 (output 17) a device 50 for the on-time correction of the ignition moment is switched on, for example, the development of NPO Avtoelektronika according to the design documentation of 2MK. 175.

 The diagram of the device 1 of the ignition system for ICE in FIG. 3 is characterized by the fact that between the output of the input driver 11 (output 18) and the input 42 of the microcircuit 4 (output 17) a switch 51 is turned on, which provides the function of an anti-theft device, for example, the development of NPO Avtoelektronika according to the design documentation 2MK. 110.

 The device 1 according to the circuit of FIG. 1 works as follows.

During the operation of the motors, the interrupter contacts periodically open and close. At the same time, a rectangular signal is formed at the input 16 (PR) of the electronic unit, moreover, the opening of the pulse front of the signal corresponds to the opening of the contacts of the chopper, and the opening of the pulse corresponds to the opening of the contacts. The process of contact closure is characterized by "bounce", as a result of which when forming a pulse slice a sequence of short pulses is formed, which is undesirable during subsequent signal processing in chip 4 (see Fig. 4 U 16). This drawback can be eliminated in the input shaper 11, equipped with an integrating circuit 43. The constant charge of the capacitor 46 is insignificant, since the resistance of the resistor 12 is several tens of Ohms (30 50). Therefore, when forming a high-level signal, the capacitor 46 is quickly charged, practically without distorting the pulse edge of the input signal (see Fig. 4 U 46). When a low-level signal is generated, the diode 45 is closed and the capacitor 46 is charged through the resistor 47 and the open transition of the BE transistor 48. Moreover, the resistance of the resistor 47 is much greater than the resistance of the resistor 12 (5 10 kΩ). As a result, a pulse signal is generated at the inverter output 18 (see Fig. 4 U 18), the front of which is delayed relative to the signal cutoff U _pr for a time determined by the constant discharge circuit of the capacitor 46.

If there is a bus 19, the output signal of the driver 11 is fed to the input 42 of the microcircuit 4, namely, to the input of the normalizing integrator 31, which generates a sawtooth periodic signal (see Fig. 4 U 31), the amplitude of which depends on the repetition rate and duty cycle of the control signal ( U _sz ). With a low signal level U _sz , a sawtooth signal front is formed, with a high drop. The signal of the normalizing integrator 31 is fed to one of the inputs of the comparator 33, which fixes the moment of equality of the voltage across the capacitor 5 to the threshold voltage generated by the correction integrator 32 (see Fig. 4 U 33). The installation of the comparator 33 in the initial state occurs at the time of formation of the slice of the pulse signal U _sz . Next, the signal of the comparator 33 is amplified by current in the output stage 29, which directly controls the switching of the switching transistor of the electronic chopper (see Fig. 4 U 40). Moreover, the moment of fixing the equality of the compared signals of the integrators 31 and 32 determines the moment of switching on the switching transistor of the chopper 2 and, therefore, the beginning of the flow of the output current in the primary winding of the ignition coil (see Fig. 4 I _output ). A voltage proportional to the output current is removed from the low-resistance resistor 23 of the output current measuring means 3 and, through a resistive divider 24 25, is supplied to the sensitive input 39 of the output current limiting means 27. When the output current reaches a predetermined value (I _p ), the output current limiting means 27 restricts the output current flowing through the switching transistor by switching it from saturation to active mode. At the time of switching off the switching transistor of chopper 2, the accumulated electromagnetic energy (1 $\genfrac{}{}{0ex}{}{\text{2}}{\text{R}}$ • L1) / 2 in the primary winding (L 1) of the ignition coil is realized in the spark gap of the spark plug. Simultaneously with the process of limiting the output current, an output signal is generated at the output of the means 27 for limiting the output current (see Fig. 4 U 27), which controls the discharge of the capacitor 6 of the correction integrator 25. At the end of the active mode, the capacitor 6 of the correction integrator 32 is slowly charged. As a result , a threshold level for comparator 33 is formed at its output (see Fig. 4 U 32), which depends on engine speed, supply voltage, inductance, and active resistance of the primary winding of the ignition coil and others outside these factors. Moreover, the ratio of the discharge and charge of the capacitor 6 is selected so that the active mode of the switching transistor of the chopper 2 is 6 from the period of the input signal of the microcircuit 5. At high engine speeds or low voltage, if the output current does not have time to reach the set value I _p control switching transistor chopper 2 is a signal.

 When the engine is stopped, a relatively slow charge of the capacitor 7 of the means 28 takes place, at the output of which, after a certain time ≈ 2 s, a signal is generated that locks the switching transistor of the electronic chopper 2, and the locking is slow so that parasitic sparking does not occur.

 The ignition system device 1 for ICE in FIG. 2 works as follows.

The signal of the contact breaker (U _CR ), converted in the input shaper 11 (U 18), as described above, is input to the device 50 for the online correction of the moment of sparking, the output of which forms a pulse signal of a rectangular shape, a slice of which is delayed relative to the front signal of the contacts of the breaker by a certain amount, called the angle of correction of the moment of sparking, and the magnitude of the angle of correction depends on the engine speed and the external controller set by the driver with subjective nke detonation. Thanks to this, a detonation-free engine operation is carried out at different octane numbers of fuel.

 Next, the output signal of the device 50 is supplied to the input 42 of the chip 4 and the operation of the device occurs, as described above.

 The ignition system device 1 for ICE in FIG. 2 operates similarly to the circuit of FIG. 1 if key 51 is closed. If the key 51 is open, the control signal does not enter the input 42 of the chip 4 and there is no sparking. Moreover, due to the presence of the means 28 for sparkless current switching off, the device 1 and the ignition coil will be de-energized. In this case, the switch S1 functions as an anti-theft device.

 The device 1 for the internal combustion engine ignition system can also be used if there is no connection between the output 18 of the driver 11 and the output 17, which is the input of the microcircuit 4. In this case, the output of the proximity sensor that the car is equipped with is connected to terminal 17 and the device 1 works as it was described above, and the second input 16 and the driver 11 are in reserve.

Claims (4)

 1. A device for an ignition system of an internal combustion engine, comprising a first input for connecting a first crankshaft position sensor, an electronic chopper, a first output terminal of which is used to connect a primary winding of an ignition coil, a second output terminal is connected to a negative pole of a DC voltage source through means for measuring the output current of the device, and the input terminal is connected to the output of a monolithic integrated circuit, consisting of at least one current, adaptive regulation of the duty cycle of the output current pulses and smooth switching off of the output current when the engine is stopped, and the monolithic integrated circuit contains a first input connected to the first input of the device, and inputs that ensure its functioning, characterized in that a second input is inserted into it for connection a second crankshaft position sensor, a resistor providing the operating current of the second sensor, and a driver with an open output, the input of which is connected to the second input, and the output is connected En with the first input of a monolithic integrated circuit.  2. The device according to claim 1, characterized in that the output of the shaper with an open output is connected to the first input of the monolithic integrated circuit through the device for online correction of the ignition moment.  3. The device according to claim 1, characterized in that the output of the driver with an open output is connected to the first input of the monolithic integrated circuit through a switch.  4. The device according to p. 1, characterized in that the shaper with an open output contains a serially connected timing circuit and an inverter, the input of the timing chain being an input and the inverter output as an output of the shaper with an open output.

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