SU1260713A1 - Device for measuring advance angle of fuel injection - Google Patents

Abstract

The invention relates to the field of engineering, in particular to the diagnosis of internal combustion engines. The invention allows to expand the functionality of the device by measuring the angles of both four-stroke and two-stroke engines, without changing the algorithm of the diagnostic process, which reduces the complexity of the process. This is achieved by introducing a one-one torus, an OR scheme, additional AND schemes, triggers, and a button. When diagnosing a two-stroke engine, pulses are generated, the frequency of which is equal to half the injection pulses. In the device, the signals at the input of the computational logic unit 8 do not depend on the tact. Block 8 calculates the desired angle. The duration of the impulse time of the additional trigger 15 is the advance injection time by filling this time with generator pulses 17. 3 sludge. i (L 1CHE O5 about 00

Description

The invention relates to the diagnosis of internal combustion engines and can be used to measure the advance angle of diesel fuel.

The purpose of the invention is to expand the functional capabilities of the device and reduce the complexity of the measurement process.

FIG. 1 shows a block diagram of the proposed device; in fig. 2 - timing charts of a four-stroke engine; in fig. 3 - the same two-stroke engine.

The device comprises a fuel injection sensor 1, an upper dead center sensor 2, connected to the inputs of the first driver 3 and the second driver 4 of rectangular pulses, respectively. The output of the first shaper 3 rectangular pulses connected to the input of the one-shot 5, the second input of the circuit OR 6, the single input of the first trigger 7. The device contains a computational logic unit 8, the third additional circuit And 9.

The output of the one-shot 5 is connected to the first input of the circuit OR 6, the output of the circuit IL1-6 is connected to the first input of the first additional circuit AND 10, the second input of the circuit 10 is connected to the output of the second shaper 4 square-wave pulses, the zero input of the first trigger 7 and the second input of the second an additional circuit And 11, the third input of the circuit And 10 is connected to the inverse output of the first additional trigger 12, and the output of the circuit And 10 is connected to the single input of the first additional trigger 12. Zero inputs of the first 12 and second 13 additional triggers Inna between themselves and with the second contact of the button 14, the first contact of which is connected to the power source (to its positive, zero or negative bus, depending on the element base used). The direct output of the first additional trigger 12 is connected to the first input of the second additional circuit 11, and the output of the circuit 11 is connected to the counting input of the second additional trigger 13. The inverse output of the trigger 13 is connected to the second input of the third additional circuit 9, direct output trigger 13 is connected to the zero input of the third additional trigger 15. The first input of the fourth additional circuit AND 16 is connected to the output of the third additional circuit AND 9, the second input of the circuit AND 16 is connected to the forward output of the first trigger 7, and output c And 16 is connected to the single input of the third additional trigger 15 and the third input of the computing unit 8. The direct output of the trigger 15 is connected to the first input of the block 8. The second input of the block 8 is connected to the generator 17 of the square pulses, and the output block 18 display. The fuel injection sensor 1 produces an electrical pulse signal at all times.

fuel supply to the cylinder, and the top 2 dead center sensor 2 produces an electrical impulse when the piston is in the TDC. The first driver 3 generates a single rectangular pulse, the duration of which coincides with the pulse duration of the injection sensor 1. The second driver 4 generates a single amplitude rectangular pulse, the duration of which is equal to the duration of the pulse of sensor 2. Single vibration 5 produces a single rectangular pulse, the leading front of which does not coincide with the end of fuel injection, and the rear front is formed after the piston has entered TDC. The circuit OR 6 summarizes the pulses of the driver 3 and the one-shot 5, as a result of which at its output there are pulses whose leading edge corresponds to the beginning of fuel injection and the rear edge takes place after the piston has entered the TDC. The triggers 7, 12, and 15 are reset to the zero state when a single signal appears on their zero inputs and go to the single state when a single signal appears on their single inputs. The trigger 13 is reset when it appears at its zero, the input of a single signal, and then transitions from the zero state to a single state and vice versa when a single pulse appears at its counting input. Circuits 9-11 and 16 at the output produce a single signal only in the case when all their inputs are simultaneously single signals. The generator 17 generates rectangular pulses, the frequency of which is much higher than the frequency of rotation of the shaft. The display unit 18 displays in digital form the measured value of the angle of lead in the decimal number system. Computational logic unit 8 provides the calculation of the injection advance angle during work cycles of a diesel engine.

Computational logic unit 8 is made on K580- and K155 series microcircuits, sensors 1 and 2 are, for example, inductive sensors with amplifiers on K140 series microcircuits, button 14 is of the KM-2 type, the display unit is implemented on K155 series microcircuits and indicator lights, for example, IN14, and all other elements of the device are made on K155 series microcircuits.

The device works as follows.

Let us first consider the case of measuring the advance angle of a four-stroke engine.

When fuel is injected, sensor 1 produces a pulse 11 (Fig. 2), which is converted by a generator 3 into a rectangular pulse of the same duration and unit amplitude (for example, the amplitude is equal to the level of a logical one).

Ti .: the end of the last one-shot:. produces a rectangular impulse b of a single amplitude, the duration of which is developed so that it ends after the moment of piston entry in TDC. Thanks to this, HJiH 6 produces a rectangular single impulse Ufb, which starts at the moment of the start of fuel injection and ends after the arrival of piston in TDC. Sensor 2 generates a pulse when the piston is at the top dead center, and driver 4 converts this pulse into a rectangular one, which is fed to the zero input of the first trigger 7 and the second inputs of the first AND 10 and second AND 11 additional coincidence circuits. The output pulses of the first imaging unit 3 also arrive at the first input of the third additional circuit 9 and the single input of the first trigger 7. The latter transits to the single state under the action of the leading edge of the indicated pulses and is reset to the zero state under the action of the leading edge of the pulses 4.

Since the case of diagnosing a four-stroke engine is considered, in which the piston enters the TDC at each revolution of the shaft and the injection is made once every two revolutions of the shaft, the single input of trigger 7 receives pulses twice as low as its zero input. In this connection, the specified trigger is cocked into one state and reset to "O" only in those shaft turns where fuel injection takes place. In all other revolutions, the signal developed at the time of the piston entry into the TDC only confirms the zero state of the first trigger 7 (the f / y plot in Fig. 2).

The measurement process starts with pressing button 14 (in Fig. 2 this corresponds to the moment |), with the result that the first 12 and second 13 additional triggers are reset to "O, and at the third input of the first additional circuit And 10 and the second input additional circuitry And 9 single signals are set. Due to the latter, the output pulse of the imaging unit 3 from the first input of the third additional circuit And 9 passes to its output and the first input of the fourth additional circuit And 16. Since the first trigger 7 goes into a single state when the leading edge of the pulse (Uz, then the inputs of the circuit And 16 Single signals appear at the same time, it opens and is set to "1 third additional trigger 15 at the time of the start of fuel injection (see the diagram in Fig. 2). At the time of the end of fuel injection, i.e. during the falling front them Pulse Uz, third and fourth circuits And 9 and And 16 are closed, a single signal at their outputs disappears, but the third additional trigger 15 remains in one state. By resetting the first additional trigger 12 and establishing a single signal at the third input of the And circuit 10 after pressing button 14, this circuit opens when a single signal V and i / e is applied at its first and second inputs, as a result of which a single signal appears at the output of this circuit at the instant of the leading edge of the pulse of driver 4 (Fig. 2 is the moment / 2). The generated pulse at the output of the circuit AND 10 sets the trigger 12 to the single state, as a result of which the first additional circuit AND 10 closes the zero-roll from the inverse output of this trigger and remains in this state until the next button has been pressed. 14. At the same time, the first additional trigger 12 saves the single state also until the next pressing of this button occurs, and at the first input of the second additional circuit AND 11 during all this time (from the moment / 2 until the next pressing of the button) there is a single The second signal allowing the second shaper 4 to pass to its output. As a result, the shaper 4 pulse following the shaper 3 pulse, ne, converts the trigger 13 reset earlier with the help of button 14 into a single state, which, in turn, resets with a single signal, the third additional trigger 15 and blocks the third and fourth additional circuits AND 9 and I 16, the output impulse which ended a little earlier - at the moment of the falling edge of the pulses of the first driver 3.

With the arrival of the next TDC pulse (second in order in Fig. 2), the second driver 4 generates a rectangular pulse, which, having passed through the second additional circuit 11, resets the second additional trigger 13 to the zero state, as a result The second input of the third additional circuit AND 9 is supplied with a single signal from the inverse output of the flip-flop 13 and it is prepared for the transmission of the next injection pulse. The pulse generated by the first generator 3 during the fuel injection period passes through the open circuit AND 9 to the input of circuit AND 16, sets the first trigger 7 to the one state and passes through the circuit OR 6 to the first input of the first additional circuit AND 10, which is closed with the zero signal the inverse output of the first additional trigger 12. Since the first trigger 7 is cocked to 1, the pulse from the first input of the AND 16 circuit goes to its output and to the single input of the third additional trigger 15, putting it into the single state. At the end of the impulse shaper 3 at the inputs of circuits And 9,

And 16, the second input of the circuit OR 6 and the input of the alternator 5 signal disappears. The latter leads to the appearance of a pulse at the output of this one-shot, which passes through the circuit OR 6 to the first input of the first additional circuit AND 10, which at that time is closed by the zero signal at the third input and does not pass this pulse to the other elements of the device.

In this way, a second pulse is formed at the outputs of the circuits AND 9 and AND 16 and the output pulse of the latter arrives at the third input of the computational unit 8.

When the next piston enters the top dead center, a pulse is generated and 4, resetting the first trigger 7 to the zero state and passing through the open circuit AND 11 to the counting input of the second additional trigger 13. As a result, the passage of the signal through the circuit 16 is prohibited, and trigger 13 is raised to " 1, locking the third additional circuit AND 9 and resetting the third additional trigger 15 to the zero state. The latter leads to the end of the output pulse trigger 15.

When the piston enters TDC in the next turn of the shaft (the fourth pulse in Fig. 2 (/ 4), the zero state of the first trigger 7 is confirmed, and the second additional trigger 13 is reset to "O and then the operation takes place in the same way as after the second TDC pulse.

The output pulse signal of the third additional trigger 15 starts at the moment of the start of fuel injection and ends at the moment when the piston approaches the top dead center and the pulse frequency is equal to the frequency of fuel injection.

When the device operates, the output pulses of the third additional trigger 15 arrive at the first input of the computational unit 8, the output pulses of the fourth additional circuit AND 16 arrive at the third input of this block, and the high-frequency pulses of the generator 17 arrive at the second input of the block 8. The specified block forms digital equivalent / V (p of the advance angle f of fuel injection by filling pulses with generator pulses 17 (the duration of these pulses is the advance timing of injection), the digital equivalent of L " the rotation of the shaft through 720 ° n in. fuel injection cycles (since each angle of 720 ° of rotation of the shaft corresponds to one cycle of fuel supply) by filling with pulses of the same frequency of the pulse following period (7 | b (this period corresponds to the angle of rotation of the shaft 720 °) and performs the calculation of the desired angle as well as the prototype according to the formula

VF 720 °.

sing

The calculated value of the fuel injection advance angle is displayed on the digital display of the display unit 18 in the decimal number system. After reading the scoreboard, press button 14, after which a new measurement cycle occurs.

When diagnosing a four-stroke engine, the proposed device works in the same way as the prototype.

Consider the operation of the device when measuring the advance angle of a two-stroke engine injection (timing diagrams are shown in Fig. 3).

During the fuel supply, the fuel injection sensor 1 produces a pulsed electrical signal, which is converted into square pulses at the input of the single-vibrator 5, the second input of the OR circuit 6, the single input of the first trigger 7, and the first input of the third additional circuit AND 9. When the sensor enters the TDC, the sensor 2 generates pulses that are converted by the shaper 4 into rectangular pulses and then arrive at the zero input of the first trigger 7, at the second inputs of the And 10 and And 11 circuits.

The measurement cycle starts at time t (in Fig. 3) after pressing button 14, after which the first and second additional triggers 12 and 13 are reset. By resetting trigger 12, a single signal is set at the third input of the first additional circuit And 10 and it is prepared for transmission pulse to exit. After the end of the pulse of the first generator 3, the one-shot 5 produces a pulse arriving at the first input of the circuit OR 6, as a result of which the output pulse of the circuit starts at the moment of the start of injection and ends at the moment of the end of the pulse of the one-vibration. Since the latter ends later than the piston enters the TDC, the pulse of the driver 4 acts on the second input of the AND 10 circuit when a single signal of the OR circuit is present at its first input, and passes through the AND 10 circuit to the single input of the first additional trigger 12. The last goes into a single state, sends a single signal to the first input of the second additional circuit And 11 and closes the first additional circuit And 10 with a zero signal of the inverse output. This circuit remains closed during the whole measurement cycle until Next, press button 14, and the second additional scheme 11 during the entire cycle transmits pulses of the second driver 4 to the counting input of trigger 13 in each revolution of the shaft. Consequently, the single and zero inputs of this trigger in each turn of the shaft are pulses, respectively, from the formers

3 and 4, as a result of which a trigger in each revolution of the shaft produces a single impulse, and this impulse begins at 3 moment of the start of fuel injection and ends at the moment of the piston entering the dead center.

The first in FIG. 3, pulse 74, the leading edge of which corresponds to the moment / 2, sets the second additional trigger 13 to one state. The latter resets the third additional trigger 15 into O, and prohibits the passage of pulses through the third additional circuit 9, applying a zero signal from the inverse output to its second input. The pulse formed by the first shaper 3, corresponding to the fuel supply pulse, in the pause between the first and second TDC pulses does not pass through the closed AND system 9 to the remaining elements of the device, including the computer unit 8. Second order (Fig. 3) the pulse of the former 4, having passed through the open circuit AND 11 to the counting trigger 13, resets it to the zero state, as a result of which the zero signal at the third additional trigger 15 returns a single signal and at the second input of the third additional circuit 9 And a single signal is made. The third impulse Uz formed after that (during the fuel supply period) (in order of Fig. 3) translates the first trigger 7 into a single state and passes through an AND 9 circuit, and an open single signal of this trigger AND 16 transforms into a single input the third additional trigger 15, converting it to a single state. Thus, at the moment of the start of fuel injection in the third fuel injection cycle, a single signal appears at the outputs of the AND 9 AND 16 N circuits of the flip-flop 15. At the end of the pulse of the first driver 3, the signals at the outputs of the third AND 9 and fourth AND 16 matching circuits and the single input of the indicated trigger stop. In addition, the action of the trailing edge of the pulse Uj at the input of the single vibrator 5 leads to the formation of a pulse (/ 5 that passes through the OR 6 circuit to the first input of the first additional AND 10 circuit, but does not have any effect on the device elements, since the AND 10 circuit is closed.

After some second time after the injection is finished, the piston enters the upper dead center and a third pulse is generated from the second driver 4 (FIG. 3), which resets the trigger 7 and charges the second additional trigger 13. As a result, the second input of the fourth additional circuit And 16 sets a zero signal, and a single signal is applied to the zero input of the third additional trigger 15. Under the action of the last specified trigger is reset and one

A negative pulse at its output ends.

In the next turn of the shaft, the shaper 3 generates a fourth pulse (on the plot 5 of Fig. 3), which converts the first trigger 7 into a single state, arrives at the first input of the third additional circuit AND 9, and initiates a single-blown 5 n through the circuit. the input of the first additional circuit And 10. However

 The AND 9 circuit is closed with a zero signal from the inverse output of the first additional trigger 12 and the specified pulse (the UZ does not pass through these circuits and does not affect the remaining elements of the device. In this connection, the third additional trigger 15 does not generate a pulse in the specified shaft rotation.

Then the next TDC pulse occurs and the device operates in the same way as described. Thus, the proposed

0, when diagnosing a two-stroke engine, the device generates pulses (/ 15 and (/ 16, the frequency of which is equal to half the frequency of fuel injection pulses or half the frequency of upper dead center impulses. When measuring the advance angle of injection of a four-stroke engine, the pulse frequency L ls and U (, is also equal to half the pulse frequency of the top dead center. This means that in the proposed device the parameters

The signals arriving at the inputs of the computational logic block 8 and by which this block calculates the desired angle do not depend on the engine tact, but only on the rotation frequency and the measured advance angle. At the same time, the duration of the pulse of the third additional trigger 15, which is the injection advance time, in the block 8, transforms into the digital equivalent of the injection advance angle by filling this time with the generator pulses 17. Period

0 of the following pulses U (, (for which the motor shaft turns at an angle of 720 °), by filling it with pulses of the generator 17, is converted in the computing unit 8 to the digital equivalent of an angle of 720 ° / g.

Further, this block calculates the injection advance angle.

Thus, the proposed device provides a measurement of the fuel injection advance angle of four-stroke and two-Q stroke internal combustion engines, i.e., compared to the known (which, without changing the calculation algorithm, only four-stroke engines can be diagnosed) has broader functionality. Wherein

5, in order to go from diagnosing engines of one tact to engines of another tact, changing the algorithm of the proposed device is not required, good5

the gift of which decreases the laboriousness of the measurement process as compared with the known device.

Claims (1)

Invention Formula A device for measuring the fuel injection advance angle, comprising injection and top dead center sensors with first and second pulse drivers, a first trigger, a display unit, a square pulse generator and a computing unit, made in the form of interconnected first and second circuits And, the first and second registers, the block for calculating the advance angle, the control circuit, and the switch, with a single trigger input connected to the output of the first pulse driver, and the zero input to the output of the second form pulse maker, the first input of the computational-logic 5 trigger, the input of the one-shot is connected to the first input of the third additional AND circuit, the second input of the OR circuit and the output of the first pulse driver, the output of the one-shot is connected to the first input of the OR circuit, the output of which is connected to 0 by the first input of the first additional circuit AND, the second input of which is connected to the output of the second pulse driver and the input of the second additional circuit AND, the output of the first additional circuit AND is connected to the single input of the first additional trigger, the direct output of which is connected to the first input of the second additional circuit AND , and inverse - with the third input of the first additional circuit And, the output of the second additional circuit And a chesky block is combined with the first input 20 is connected to the counting input of the second do25 the first AND circuit, the second input of the computational logic unit, combined with the second inputs of the first and second AND circuits, is connected to the square pulse generator, the third input of the computational logic unit is combined with the control circuit input, and the output of the computational logic unit is combined with the output calculating the angle of advance and is connected to the display unit, characterized in that, in order to expand the functional possibilities and reduce the laboriousness of the measurement process, a one-shot, OR, first, sec , Third and fourth additional circuits, and the first, g g g an additional trigger, the direct and inverse outputs of which are connected respectively to the zero input of the third additional trigger and the second input of the third additional circuit AND, the output of which is connected to the first input of the fourth additional circuit AND, the second input of which is connected to the direct output of the first trigger And connected to the single input of the third additional trigger and the third input of the computational logic unit, and the output of the third additional trigger connected to the first input ode computing computing unit. gg gg l st / Jzl PP PDI HZ th ; and. tz I A l I-I-I-g Jzl 2 Compiled by N. Patrakhaltsev Editor N. Gorvattehred I. VeresKorrektor S. Cherni Order 5217/38 Circulation 778 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab. 4/5 Branch PPP "Patent, Uzhgorod, st. Project, 4 , a swarm and a third additional triggers and a button, the first contact of which is connected to the power source, and the second with the zero inputs of the first and second additional flip-flops, the one-shot input is connected to the first input of the third additional AND circuit, the second input of the OR circuit and the output of the first pulse shaper, the single-shot output is connected to the first input of the OR circuit, the output of which is connected to the first input of the first additional circuit And, the second input of which is connected to the output of the second pulse driver and the second input of the second additional circuit And the output of the first additional circuit And connected to the single input of the first additional trigger, the direct output of which is connected to the first input of the second additional circuit And, and inverse - with the third input of the first additional circuit And, the output of the second additional circuit And - an additional trigger, the direct and inverse outputs of which are connected respectively to the zero input of the third additional trigger and the second input of the third additional circuit AND, the output of which is connected to the first input of the fourth additional circuit AND, the second input of which is connected to the direct output of the first trigger And connected to the single input of the third additional trigger and the third input of the computational logic unit, and the output of the third additional trigger connected to the first input ode computing computing unit. gg gg A l P l  P tz l lp P Ezl WITH gp g g fpui.J