RU94639U1 - CAR IGNITION SYSTEM - Google Patents

Abstract

 An automobile ignition system comprising a piston position sensor in an engine cylinder, the induction winding of which has a phase angle corresponding to the position of the piston in the cylinder to the top dead center (TDC), a pulse shaper connected to the terminals of the induction winding, and a controllable delay element connected in series with it, amplifier-driver, current chopper, ignition transformer, high voltage distributor and spark plugs located in the engine cylinder, characterized in that it is introduced We have a reference clock generator, a pulse counter, a memory register, a fixed delay element, a counting input of a pulse counter connected to the output of a reference frequency pulse generator, a zeroing input to the fixed delay element input, and an output to a memory register information input whose recording input connected to the output of the pulse shaper and the input of the fixed delay element, the output of the memory register is connected to the control input of the controlled delay element, while the element of controlled the holder contains a clock pulse generator of a reference frequency, an OR logic element, a pulse counter and a code comparator, the first input of which is connected to the output of the pulse counter, the second is the control input of the delay element, and the output is the output of the delay element and connected to the first input of the OR element, the second input The OR element is the signal input of the delay element, and the output is connected to the zeroing input of the pulse counter, the counting input of which is connected to the output of the clock generator.

Description

The utility model relates to the automotive industry, namely to electrical equipment for ensuring the operation of internal combustion engines, and can be used in the production and operation of automotive equipment.

A known ignition system of the working mixture in a car engine, comprising an ignition transformer, a voltage distributor connected to the secondary winding of the transformer, spark plugs connected to a voltage distributor, a current transformer of the primary winding of the transformer, a piston position sensor in the engine cylinder in contact with the chopper and mechanically connected to voltage distributor shaft [A.G. Sergeev, V.E. Yutt. Diagnostics of electrical equipment of cars. - M .: Transport. - 1987].

All of the listed elements of this analogue are also included in the inventive utility model of the ignition system.

The work of this analogue is based on the formation of high electrical voltage by interrupting the current in the primary winding of the ignition transformer when the electrical contacts are disconnected during the period when the combustion rate of the working mixture is maximum, that is, after the maximum compression point or top dead center (TDC).

The disadvantage of this analogue is the sparking on the contacts during interruption of the current, due to the mechanical method of interrupting it.

The ignition system of a vehicle’s internal combustion engine is also known, comprising an ignition transformer, a voltage distributor connected to the secondary cover of the ignition transformer, spark plugs connected to a voltage distributor, an electronic current chopper of the primary coil of the ignition transformer, a piston position sensor in the engine cylinder connected to the chopper and mechanically connected to the shaft of the distributor [Danov B.A., Rogachev V.D., Electrical equipment of KamAZ vehicles. - M .: Transport. - 1997].

All of the listed elements of this analogue are also part of the claimed utility model of the ignition system.

In this analogue, current interruption is carried out using an electronically controlled transistor, which eliminates sparking at the contacts. The control signals are received from an induction sensor mechanically connected to the engine crankshaft, which allows generating signals for controlling the transistor taking into account the position of the piston in the cylinder. The length of time from the moment the control signal is applied to the transistor chopper to the moment of the most intense burning of the working mixture depends on many factors (rotation speed, composition of the working mixture, discharge, etc.) Therefore, the voltage is supplied to the spark plugs ahead of time to the TDC position . To combine the time of the most intense combustion of the working mixture (detonation time) with the desired piston position, which is able to convert the combustion energy to mechanical energy as much as possible, mechanical controllers of the ignition timing are used.

The disadvantage of this analogue is that mechanical regulators do not allow to take into account all available factors that significantly affect the ignition time of the working mixture (development of a spark charge). This significantly limits the range of operating conditions of the engine in a mode close to the most economical.

Closest to the technical nature of the claimed (prototype) is the car ignition system, protected by RF patent No. 2306451 class. F02P 1/00, 2006. It contains a piston position sensor in the cylinder with three induction windings having phase angles corresponding to the TDC of the piston position in the cylinder, before and after TDC, four pulse shapers, a controllable delay element in series, an amplifier-shaper, a current chopper, an ignition transformer, a high voltage distributor and spark plugs located in the engine cylinder, a pressure sensor located in the engine cylinder, a time shift meter, the first and second inputs of which through the first and second pulse shapers, respectively, connected to the terminals of the induction winding with the phase after the TDC of the piston position sensors and the output of the pressure sensor, a time-voltage phase-amplitude converter connected between the output of the time-shift meter and the control input of the controlled delay element, the signal input of which is through the third a pulse shaper is connected to the terminals of the induction winding with a phase up to TDC, and a synchronizer, the input of which through the fourth pulse shaper is connected to the conclusions of the induction winding with a phase corresponding to TDC, and the first and second outputs are connected to the sync inputs of the controlled delay element and the time shift meter, respectively.

All of the above elements of the prototype, except for the pressure sensor and induction windings with the phases of the TDC and after the TDC, the second, third and fourth pulse shapers, synchronizer and time-shift meter are included in the inventive system.

The work of the prototype is based on the formation of three hardware channels for controlling the ignition of the car, corresponding to the three positions of the piston in the cylinder, and controlling the delay of the pulse of the induction winding of the piston position sensor with a phase up to the TDC entering the current interrupt circuit so that the detonation pulse of the pressure sensor coincides with the pulse induction winding of the position of the piston with a phase after TDC.

The disadvantages of the prototype are the complexity and relatively low reliability due to the large number of its constituent elements.

In addition, in the case of changes in vehicle speed over a wide range, the system operates unstable. Under these conditions, it may end up in such a mode that, at the current speed, the time span of the pressure sensor pulse with the pulse of the winding with the phase after TDC can be so significant that it cannot be detected by a time-shift meter, or the pressure pulse will not be generated at all. A search mode optimal, or close to that of the delay of the controlled delay element in the system is not provided.

The technical problem to which the utility model is directed is to simplify the system and increase its reliability and stability.

The solution to this problem is achieved by the fact that in a known ignition system of a car containing a piston position sensor in the engine cylinder, the induction winding of which has a phase angle corresponding to the position of the piston in the cylinder to the TDC, a pulse shaper connected to the terminals of the induction winding and connected in series with it controlled delay element, amplifier driver, current chopper, ignition transformer, high voltage distributor and spark plugs located in the engine cylinder i, a reference clock generator, a pulse counter, a memory register and a fixed delay element are introduced, a counting input of a pulse counter is connected to the output of a reference frequency pulse generator, a zeroing input is at the input of a fixed delay element, and an output is at the information input of the memory register, input the recording of which is connected to the output of the pulse shaper and the input of the fixed delay element, the output of the memory register is connected to the control input of the controlled delay element, while the control element The delay contains a reference clock generator, an OR logic element, a pulse counter and a code comparator, the first input of which is connected to the output of the pulse counter, the second is the control input of the delay element, and the output is the output of the delay element and connected to the first input of the OR element, the second the input of the OR element is the signal input of the delay element, and the output is connected to the zeroing input of the pulse counter, the counting input of which is connected to the output of the clock generator.

The totality of the newly introduced elements and relationships and the feature of the execution of the controlled delay element is not an independent device and does not follow explicitly from the prior art. There are no sources of information in which it was described independently or in conjunction with other elements of the claimed system. This allows us to consider the claimed utility model new.

The essence of the utility model is illustrated in the figure, which shows:

- figure 1 is a structural diagram of the inventive ignition system;

- figure 2 is a structural diagram of a controlled delay element;

The proposed ignition system comprises an induction sensor 1 with a magnetic bipolar rotor 2 mechanically connected to the crankshaft (KB) of the engine and having unambiguous angular positions corresponding to the angular positions of KB and the positions of the piston in the engine cylinder. An induction winding 3 is located on the sensor stator. Its position corresponds to an angle of about 60 degrees to TDC. The system also includes a 4-pulse shaper, a controlled delay element 5, an amplifier-shaper 6, a current chopper 7, an ignition transformer 8, a high voltage distributor 9, spark plugs 10 located in the engine cylinder 11, a reference clock generator 12, a counter 13 pulses, fixed delay element 14, memory register 15.

The output of the induction winding 3 through the shaper 4 is connected to the signal input of the element 5, the input of the element 14 and the input of the register 15. The ignition pulse channel contains series-connected element 5, the amplifier-shaper 6, the chopper 7, the transformer 8, the distributor 9 and the candles 10. Input resetting the counter 13 is connected to the output of the element 14, the counting input to the output of the generator 12, and the output to the signal input of the register, the output of which is connected to the control input of the element 5.

The delay element 5 contains a generator 5.1 clock pulses of the reference stable frequency, many times higher than the pulse repetition frequency of the shaper 4, element 5.2 OR, counter 5.3 pulses and comparator 5.4 codes. The counter counter 5.3 input is connected to the output of the generator 5.1, the zeroing input is connected to the output of the element 5.2, and the output is connected to the first input of the comparator 5.4, the second input of which is the control input of the element 5. The output of the comparator 5.4 is the output of the element 5 and connected to the first input of the element 5.2 whose second input is the signal input of element 5.

The operation of the ignition system is as follows.

When the motor KB rotates, the sensor 1 periodically with a period T corresponding to the angular velocity generates a voltage in the winding 3, from which the shaper 4 generates short pulses. These pulses are generated at times preceding extremely early ignition. The generated pulses go directly to the signal input of the delay element 5 and to the input of the register 15, and through element 14 to the input of resetting the counter 13. The contents of the counter 13 are transferred to register 15. The delay of element 14 is sufficient for this overwriting, therefore, after it is over, the counter zeroed out. At its counting input, the output of the generator 12 receives pulses of a stable reference frequency, many times higher than the maximum possible pulse repetition rate of the former 4. The counter starts counting these pulses. By the time a new pulse of the shaper 4 arrives, its content becomes equal to the ratio of the period T to the pulse period of the generator 12. With the arrival of a new pulse, the contents of counter 13 are again rewritten into register 15 and the counter is reset to zero. The process is then repeated.

Thus, in the steady state, a number 15 is formed in the register 15, which is proportional to the period T, that is, inversely proportional to the angular velocity ω KV.

The pulses of the shaper 4 act as sync pulses.

The combustion rate of the working mixture and, in general, the possibility of its ignition depends to a large extent on the ignition timing τ, i.e. from the time interval between the pulse of the shaper 4 and the moment of sparking. This period of time, in turn, substantially depends on the angular velocity KB, and therefore on the period T of the pulse shaper 4. It should be noted that each value of period T has its own optimal ignition timing τ, which ensures maximum pressure in the cylinder. It can be roughly assumed that the ignition lead time τ, which provides the maximum pressure in the cylinder, is connected with the period T by a direct proportional dependence. The selection of the reference frequency of the generator 12 implements the required coefficient of proportionality between the period T and time τ. At the control input of element 5, a control code is received, under the influence of which the pulse received at the signal input of this element is delayed in it by a time τ corresponding to the required ignition advance.

This is as follows.

The input pulse from the signal input through the element 5.2 OR is fed to the counter zeroing input 5.3. The latter is reset to zero. At its counting input from the output of the generator 5.1, pulses of a stable reference frequency are received, many times higher than the maximum possible pulse repetition rate of the shaper 4. The contents of the counter 5.3 increases linearly. It from its output goes to the first input of the comparator 5.4, the second input of which from the output of register 15 receives the code of the number corresponding to the required delay τ. At the time of equalization of the codes at the inputs of the comparator 5.4, that is, after a lapse of the moment of receipt of a pulse at the signal input of element 5, the comparator 5.4 is activated. At the output of element 5, a short pulse is generated, which passes through element 5.2 to the input of zeroing counter 5.3. With a new pulse of the shaper 4, the process is repeated in the general case for a new value of the control code from the output of the register 15.

Thus, after the lapse of the appearance of each pulse at the signal input of element 5 of the corresponding time interval τ, a control pulse of the transistor chopper 7 of the primary current of the transformer 8 appears.

Further, as in the prototype system, these pulses are amplified by the shaper 6, the current chopper 7 in the circuit of the transformer 8 is activated, and using the high voltage distributor 9 and candles 10, the working mixture is ignited in the cylinder 11.

Thus, in the proposed ignition system, as well as in the prototype system, sparking is ensured at times that provide maximum pressure in the engine cylinder. However, in the inventive system, the angular velocity KB can vary within wide limits, so the system adapts to the actual speed KB and changes the ignition timing in accordance with the change in the angular velocity of the HF. This fact makes the system more stable than analogues and prototype.

It is easy to see that the claimed system is much simpler than the prototype, since it does not contain a pressure sensor, a second and third induction windings, a second, third and fourth pulse shaper, a synchronizer and a time shift meter. Greater simplicity and higher stability in operation provides the system with higher reliability. The calculation shows that the MTBF of the proposed system is approximately 15% higher than that of the prototype system.

The proposed utility model of the ignition system is quite easy to implement. Newly introduced elements can be made on the basis of integrated circuits of the 530, 533 series [see, for example, V.L.Shilo. Popular chips TTL - M: Argus - 1993]. The remaining elements of the system do not differ from the corresponding elements of the prototype system.

Claims (1)

An automobile ignition system comprising a piston position sensor in an engine cylinder, the induction winding of which has a phase angle corresponding to the position of the piston in the cylinder to the top dead center (TDC), a pulse shaper connected to the terminals of the induction winding, and a controllable delay element connected in series with it, amplifier-driver, current chopper, ignition transformer, high voltage distributor and spark plugs located in the engine cylinder, characterized in that it is introduced We have a reference clock generator, a pulse counter, a memory register, a fixed delay element, a counting input of a pulse counter connected to the output of a reference frequency pulse generator, a zeroing input to the fixed delay element input, and an output to a memory register information input whose recording input connected to the output of the pulse shaper and the input of the fixed delay element, the output of the memory register is connected to the control input of the controlled delay element, while the element of controlled the holder contains a clock pulse generator of a reference frequency, an OR logic element, a pulse counter and a code comparator, the first input of which is connected to the output of the pulse counter, the second is the control input of the delay element, and the output is the output of the delay element and connected to the first input of the OR element, the second input The OR element is the signal input of the delay element, and the output is connected to the zeroing input of the pulse counter, the counting input of which is connected to the output of the clock generator.