JPH0121347B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes an ignition pulse generator and a first counter, the first counter being connected to a knock signal generator to determine its counting state upon generation of the knock signal. The present invention relates to a device for shifting the ignition point of an internal combustion engine in the event of a knock, increasing the ignition time and decreasing its counting state upon changes in the operating state of the internal combustion engine.
It is already known from DE 28 32 594 A1 to control the ignition point in dependence on the knock of the internal combustion engine. In this case, an up/down counter is provided on the knock signal output side, and the counter counts in an increasing direction (incremental counting) every time it receives a knock signal, and on the other hand, when a knock signal is detected within a predetermined period. If no signal is input, counting is performed in a decreasing direction (decrement counting is performed). The instantaneous sum signal of the summed signal and the subtracted signal is fed to an electronic ignition control device, so that the ignition point of the engine is delayed as a function of this instantaneous sum. This ignition timing adjustment therefore corresponds to the knock frequency. However, the ignition system always requires a delay adjustment over a predetermined angle of the crankshaft. Therefore, when the rotational speed is high, the predetermined crankshaft angle is quickly reached, so the time displacement must be shortened.
On the other hand, at low rotational speeds, the predetermined crankshaft angle cannot be reached quickly and the delay must be increased. Traditionally, digital
An analog converter was used to convert the knock frequency into an analog signal, which controlled the ignition system. This conventional device has the following drawbacks.
That is, digital-to-analog conversion reduces a given accuracy that could be achieved with digital processing and also requires modification of the ignition circuit itself. In the known devices, it is therefore not possible to carry out ignition adjustments in devices that are already installed, and the ignition device and the device for preventing knocking have to be precisely aligned with each other.
It was necessary to configure it into one unit.

According to the device having the structure described in claim 1 of the present invention, the following advantages can be obtained. That is, the device of the invention can generate a delayed signal at its output when controlled by an ignition pulse generator and can therefore be connected to any of the ignition devices known or even in the development stage. This is an advantage. No maintenance or modification to the ignition device itself is necessary, so that existing ignition devices can be retrofitted with the device according to the invention. The device according to the invention can be inserted between the ignition pulse generator and the ignition device without additional costs.

In an embodiment of the invention, the product of the first counter and the further counter is read into a third counter to determine the displacement of the ignition point according to the time at which the third counter reaches a predetermined value. The predetermined value is then preferably chosen to be zero. With this configuration, it is possible to achieve an adjustment synchronized with the original ignition pulse in a simple form and manner. The decrement counting (counting in the decreasing direction) generates a new pulse when a low value is reached, and advantageously, the generation of this pulse is delayed the higher the original counting state of the third counter. . In this way, the ignition timing is adjusted in a retarded direction as the value of the product of the first counter and the further counter increases. After each ignition pulse, a signal is generated at the output of the device, with or without delay, and this signal is reset again after a certain period of time. This can be done, for example, using a monostable multivibrator. However, the use of a counter further simplifies the construction. If no knocks appear for a long time, so that the first counter counting the knocks is at its lowest value, the multiplication will also not give a signal to the third counter, so that this In this case, no decrement counting takes place and a continuous signal appears at its output. However, if the product of the first counter and another counter increases by a predetermined value before being read into the third counter, even if no knock appears for a long time, the third counter The counting state of is not always the same, it is always set, and it is impossible for a signal to always appear at its output. The delay introduced in this way is very small if 1 is set as the predetermined value. However, depending on the position of the ignition pulse generator, it may also be advantageous to set other values that allow a constant and unambiguous delay. The counting pulses for setting or loading a number proportional to the rotational speed and for decrementing the third counter are advantageously taken from a clock generator. In this way, the resolution is large and is only limited by the maximum processing frequency of the component.

Further, it is preferable that the counting state of the first counter for counting knocks is decreased more slowly than its increase. That is, when a knock occurs and the ignition timing is to be adjusted later, it is not preferable to perform the ignition advance adjustment again immediately after the knock disappears. The internal combustion engine must be allowed a certain amount of time to reach stable operating conditions, after which the ignition timing must be adjusted slowly again.

During actual driving, the first step is to count the knocks.
A blocking device can be provided which prohibits the counter from falling below a predetermined value, in most cases the value zero. Decrementing the counting state cannot be done only if there is no knock. Instead, it is proposed that the counting state is simply incremented on the appearance of a knock pulse, and that the counting state of the first counter is reduced or completely reset with variations in the load or rotational speed of the internal combustion engine.

In order to prevent erroneous counting pulses from being input to the first counter, the signal of the knock signal generator and its evaluation processing circuit are gated to allow them to reach the counter only when knocks can occur in the internal combustion engine. Preferably, a circuit is provided. For this reason, a gate period generation circuit is provided. In a device configured according to the invention, such a gating period can be obtained from the ignition pulse without additional reference markings. In that case, the gate period generation circuit is composed of two counters, one of which is read with a signal proportional to the rotational speed. The above two counters are decremented by a predetermined clock, and each generates a signal when a predetermined counting state is reached, in which case the first signal opens the gate and the second signal to close the gate again. This can be achieved by detecting different counting states. In this connection, one counter may suffice in simple embodiments; however, the clock frequency with which the counter is decremented has different lengths in the two counters described. With this configuration, it is possible to open a speed-dependent gate in a simple manner and in a simple manner, the gate period existing over a constant angle with respect to the reference mark at a certain crankshaft speed. It is proposed here to use an ignition pulse as the reference mark.

Embodiments of the invention are shown in the accompanying drawings.
These embodiments will be described in detail below.

Referring to FIG. 1, an engine 10 is provided with a knock signal generator 11 and an ignition pulse generator 12 with associated processing electronics. The knock signal generator 11 is connected to the counter 13,
On the other hand, a further conductor leads from the ignition pulse generator 12 to the counter 14 . The outputs of these two counters are connected to a multiplier 15. The output terminal of the multiplier 15 is connected to a third counter 16. Two conductors are connected to the connecting conductor between the ignition pulse generator 12 and the counter 14, which conductors are connected to the transfer input of the counter 13 as well as to the third counter 16 via a delay circuit 17. is connected to the transfer input terminal of the

In the ignition pulse generator 12, the engine 10
One pulse is generated for each revolution of the crankshaft. Between the two pulses generated by this ignition pulse generator, pulses proportional to the rotational speed from a clock generator (not shown) are counted incrementally (i.e. in an additive direction) in a counter 14. . At the same time, a transfer pulse is generated in the counter 13. On the appearance of a transfer pulse, the counter 13 increments its value by one when a signal is generated by the knock signal generator with the occurrence of a knock in the internal combustion engine 10.
If no knock occurs, counter 13 is decremented by one. Appropriate means are used to prevent the contents of the counter 13 from falling below the value zero, and to ensure that the counter counts in the decrement direction more slowly than in the increment direction, if necessary. The counting states appearing at the outputs of the counters 13 and 14 are transferred to the multiplier 15
are multiplied by each other and read into the counter 16. Reading into the counter 16 takes place by means of a firing pulse with a certain delay. In this case, therefore, the ignition pulse is generated by the ignition pulse generator 12 and delayed by the delay circuit 17. This delay is required for processing, particularly multiplication operations. If the value calculated by the multiplier 15 is supplied to the counter 16, the counter 16
is counted backwards, ie, in a decrementing direction, by pulses generated by a clock generator (not shown) and produces a pulse at its output when the value zero is reached. Depending on the number of knock pulses supplied to the counter 13 and as a function of the rotational speed, a stepwise retardation of the ignition takes place until the point at which the knock no longer appears. An early adjustment is made as soon as the notch does not appear again. At the output of the counter 16 appears a displaced ignition pulse which is used directly for controlling commercially available electronic ignition systems. Devices of this type can therefore be easily integrated into existing ignition systems or can also be provided to improve the functionality of already developed ignition systems.

FIG. 2 shows the ignition pulse control system. Engine 10 is also provided in this arrangement with a knock signal generator 11 and an ignition pulse generator 12 together with an evaluation processing circuit. The output of the knock signal generator 11 is connected to the input of a first counter 13, while the output of the ignition pulse generator 12 is connected to a further counter 14. A further conductor emerges from the ignition pulse generator 12 and leads to a counting input of a first counter 13. The outputs of the counters 13 and 14 are also connected in this embodiment to the inputs of a multiplier stage 15, and the output signal of the multiplier stage 15 is fed to the input of a third counter 16. be done. A conductor for counting input of the counter 16 comes out from the counter 13, and this conductor has a conductor for the count input of the counter 16.
A pulse appears when the content of 3 changes. Furthermore, the engine is provided with an operating characteristic value sensor 18, which sensor 18 is connected to the reset input of the counter 13. Such operating characteristic values can be, for example, the rotational speed of the engine or also the load on the engine.

Ignition pulse generator 12 generates one pulse for each crankshaft rotation of engine 10 . Counter 14 is supplied with a number inversely proportional to the rotational speed by a clock generator (not shown) during pulse pauses. At the same time, a transfer pulse is generated in the first counter 13. This counter 13 increments its value by one when the signal from the knock signal generator 11 is applied, and otherwise holds its value. The count states appearing at the output terminals of counters 13 and 14 are multiplied together by multiplier 15 and output to counter 1.
It is applied to the input terminal of 6. However, counter 1
6, the rotation speed changes, i.e. counter 1
It is only required when 4 changes its value or when a notch appears, ie when counter 13 changes its value. When a count signal is applied from the ignition pulse generator 12 and the appearance of a knock pulse causes the counting state of the counter 13 to change incremented by 1, a transfer signal is generated in the counter 16, which causes the counting to start. The newly determined value is transferred to the device 16. If the rotational speed or the load changes and is detected by the operating characteristic value sensor 18, the counter 13 is reset completely to zero or is returned to a predetermined value. In this case as well, the value in counter 13 changes and a transfer pulse appears to counter 16. In this case as well, the newly determined value is received by the counter 16. On the appearance of a knock, the ignition is adjusted in the retarded direction by the increment of the counter 13 in the counter 16, and this retard adjustment is maintained even if the knock no longer appears. Furthermore, this delay adjustment can only be adjusted to a further delay by means of new notches. Early adjustment is performed when other parameters of the engine 10 change. For example, if the rotational speed changes, not only the counting state of the counter 14 but also the counter 13 is reset to zero by means of a reset pulse generated by the operating characteristic value sensor 18. In that case, the delay adjustment is no longer carried out, but is started only when a new knock occurs.
The counter 16 always holds the last value supplied until a new counting pulse is input. The delay adjustment is accomplished by decrementing the counter state each time a firing pulse is generated until it reaches a value of zero or another predetermined value. With a time delay corresponding to the counter state, a pulse is generated at the output of the counter 16, which in this embodiment can also be used directly to the ignition device. In this circuit arrangement, too, a knock in the engine 10 only causes a retarding adjustment, whereas a change in other operating parameters, such as load or rotational speed, causes an earlier adjustment.

An embodiment of a control system for adjusting the ignition timing retard due to the occurrence of knocks is shown in detail in FIG. A signal from an ignition pulse generator 20 provided in an internal combustion engine (not shown) is supplied to a pulse shaper 21 to convert the ignition pulse into a rectangular signal.
The output terminal of the pulse shaper 21 is connected to the 1 of the AND circuit 22.
2 input terminals, input terminal of delay circuit 23, inverter circuit 2
4 and the input end of the frequency divider 25. Furthermore, a negative edge triggered reset input of a flip-flop 26 is connected to the output of the pulse shaper 21. A knock signal generator 27, which is attached to the internal combustion engine (not shown), is connected via an evaluation circuit 28 to the set input of the flip-flop 26. A gate period generation circuit 29 acts on the evaluation circuit 28 .
The output terminal of the AND circuit 22 is the flip-flop 3
0 set input terminal. flip-flop
The output of the flop 30 is connected to the starting input of a third counter 31. Output end 1 of counter 31
9 is coupled to an ignition system (not shown) and is connected to the reset input of flip-flop 30 and the negative input of AND circuit 22.
The output terminal of the delay circuit 23 is connected to the transfer input terminal of the counter 31. A clock input of the counter 31 is connected to a clock generator 32. The output terminal of the flip-flop 26 is connected to the increment or up input terminal of the first counter 33 and to the negative input terminal of the AND circuit 34.
Further, the output terminal of the frequency divider 25 is connected to the AND circuit 34. The conductor of the counter 33 is connected to the third negative input terminal of the AND circuit 34,
The conductor generates a signal when the value zero is present in the counter 33. Another clock frequency from clock generator 32 is applied to the clock input of another counter 35. The gate input terminal of the counter 35 is further connected to the output terminal of the NOT circuit 24. The output terminal of the NOT circuit 24 is further connected to the transfer input terminals of memories 36 and 37. Data conductors extend from counter 35 to memory 36 and from memory 36 to multiplier 38. Another input of the multiplier 38 is connected to the first counter 33 via a data conductor. The output data conductor of multiplier 38 extends to memory 37 where a one bit signal 39 is supplied. The output of the memory 37 is connected to the third counter 31 via another data conductor.

Next, the operation mode of the circuit shown in FIG. 3 will be explained in detail with reference to the pulse diagram shown in FIG. At the output end of the pulse shaper 21,
The ignition pulse shown in appears. These pulses are applied to an AND circuit 22 which sets a flip-flop 30 if no signal is present at the other input of the AND circuit 22. If a value different from zero is present in the counter 31, no signal appears at the output 19 of the counter 31 and thus also at the other input of the AND circuit 22.
In order to carry out the above operations after each firing pulse even if no knock is detected, at least one bit signal 39 is input to the memory 37 for each firing pulse. The counter 31 therefore takes on a value that is 1 larger corresponding to the product of the multiplier 38 after the transfer pulse obtained from the previous ignition pulse is delayed via the delay circuit 23 as shown in FIG. 4, m. have In FIG. 4d, the counting state of the counter 31 is shown as the height of the pulse. flip flop 30
is set by the ignition pulse, counter 3
The number present at 1 is counted backwards, ie, in a decreasing direction (ie, decremented) by a clock generated by clock generator 32. If this value is only 1, since no knock signal is applied, the zero state is reached very quickly, so that a signal appears at the output 19 very quickly after the application of the ignition signal, and this signal continues until a new value is written into the counter 31 after a delay time by the delay circuit 23. When a new value is written, the counter is reset as shown in FIG. 4d. The amount of delay increases as the number present in the counter 31 increases. This is because backward or decrement counting requires corresponding time. This will be understood from the fifth pulse shown in Figure 4d. Once a signal is generated on conductor 19, AND circuit 2 is applied to subsequent pulses from pulse generator 20 or its evaluation circuit 21.
2 is prevented, so that the possibility that the interfering pulse causes any function is excluded. Additionally, flip-flop 30 is reset via a reset input. FIG. 4c shows the pulses appearing at the output of flip-flop 30. The pulse width of this pulse corresponds to the time in which the original pulse is displaced. Only the number 1 is stored in the counter 31, so that the reset pulse is shifted in a very short time, so that an approximately needle-shaped pulse appears at the output of the flip-flop 30.
If a knock occurs and the count state of counter 31 increases correspondingly, the reset will take place at a later time, so that the flip-flop will also be reset later. This will be understood from the seventh pulse. As shown in FIG. 4m, the delay circuit 23 controls the ignition pulse appearing at the output of the pulse shaper 21 so that the supply or transfer of the count value to the counter 31 is the maximum value at which the counter 31 can appear. is also delayed, as is done when the count is definitely decremented to zero. Only then are new counted values transferred. This delay time can be seen from the rising edge of the counter state in FIG. 4d.

The ignition pulse shown in FIG. 4a is negated by the negation circuit 24 as shown in FIG. 4b. Counter 3
During the time that a signal is applied to counter 35, pulses (FIG. 4e) are sent by clock generator 32 to counter 35.
is read into. The counting state read into the counter 35 after the end of the pulse shown in FIG. 4, b) is inversely proportional to the rotational speed of the internal combustion engine. Immediately after this reading, this counting state is transferred to the memory 36 at the trailing edge of the pulse shown in FIG.
It becomes available.

The knock signal received via the knock signal generator 27 is evaluated by an evaluation processing circuit 28. Such an evaluation processing circuit is, for example, DE-OS.
(West German Patent Application Publication) No. 2918420. A gate period generation circuit 29 is used to remove interfering pulses. At the output of the evaluation processing circuit 28, a pulse appears when a knock occurs in the engine. The output signal of this evaluation processing circuit 28 is shown in FIG. 4f. A knock occurs,
When detected by the knock signal generator 27, a pulse is generated by the evaluation processing circuit 28. This knock signal pulse sets flip-flop 26, and the trailing edge of the subsequent firing pulse resets flip-flop 26. The signal appearing at the output of flip-flop 26 is shown in FIG. 4g. Each time a signal appears at the output of flip-flop 26, the count state of counter 33 is incremented by one. Figure 4h
The level of the counting state of the counter 33 is shown as an amplitude. Counter state 1 at first notch
is achieved, and on the second knock, counter state 2 is achieved, and so on. If no knocks occur, the value of this counter state is first held at that value and then counted backwards again (i.e., decremented). This backward counting is done in dependence on the ignition pulse. However, it is not meaningful to reset the counter 33 with each firing pulse. This is because, in such a case, a continuous oscillation appears between the knock in the internal combustion engine and the point at which the knock no longer occurs. Therefore, the reset pulse is reduced by frequency divider 25. This frequency divider can be, for example, a divisor 2 frequency divider, in which case a pulse as shown in FIG. 4i appears at its output. Of course, this frequency division ratio can be set to an integral multiple. A division ratio of 10 to 20 has been found to be advantageous in practical operation. Via the AND circuit 34, the pulse shown in FIG. 4i is applied to the decrement counting input, ie, down input, of the counter 33 to decrease its counting state. However, decrementing or decreasing the counter state should only occur when there is no knock signal and the count state is greater than zero. For this reason, the AND circuit 34 has two further inputs, which indicate whether the flip-flop 26 has been set by the knock signal pulse or the counter 33 has already reached its counting state zero. , the generation of pulses at the output of the frequency divider 25 is prohibited.

The data signal applied to the output of the counter 33 is multiplied in a multiplier 38 by a data value that is inversely proportional to the rotational speed. This data value, which is inversely proportional to the rotational speed, is shown in FIG. 4, k, and as shown in FIG. Incrementally counted 4th
Memory 3 at the negative edge of the negated pulse shown in figure b
Transferred to 6. The amplitudes shown in FIGS. 4J and 4K represent the count values.

The result obtained in multiplier 38 is transferred to memory 37 at the positive edge of the negated ignition pulse shown in FIG. 4b. This signal is shown in FIG. 4l. The amplitude also corresponds to the counting state in this case. memory 3
The counter state transferred to 7 becomes equal to zero when the first counter 33, which records the knock, reaches a counting state of zero. The transferred value has a finite value if the counting state of the counter 33 differs from zero. For the reasons already mentioned, the value read in memory 37 is 1.
is incremented by

The counting state stored in the memory 37 is stored in the delay circuit 2.
The ignition pulse is transferred to the counter 31 by an ignition pulse delayed by 3 (see FIG. 4m). Therefore, the amplitude increased by 1 shown in FIG. 4l) returns again to the amplitude shown in FIG. It is a measure of time.

The entire circuit arrangement can obviously also be realized in analog form. Integrate the pulse with an integral element instead of a counter. Multipliers can also be realized as analog circuits. In that case, a signal is generated when the capacitor of the integrating element storing the product has a voltage of zero.

FIG. 5 shows an embodiment in which anti-knock control can be realized in conjunction with the circuit arrangement shown in FIG. For this purpose, and gate 34
is replaced by AND gate 40. An output 45 of AND gate 40 is coupled to a decrement counting input of counter 33, while AND gate 4
The zero negative input 41 is connected to the output of a counter 33, which generates a signal when its counting state reaches zero. Input 42 is connected to the output of frequency divider 25, while negative input 43 of AND gate 40 is connected to the output of flip-flop 26. A switch 44 is connected to yet another negative input terminal of the AND gate 40, and the other end of this switch is grounded. When a notch appears, the counter 33 is counted in the additive direction (ie, counted increments) in the manner already described. With additionally provided inputs,
Decremental counting can only occur when switch 44 is closed and a logic ``1'' is applied to AND gate 40 by means of the negative input. If the other conditions are met, i.e. the counter is not at zero value, the ignition pulse clock divided by frequency divider 25 is applied, and no knock pulse is generated. At , switch 44 is closed and a backward counting or decrementing process is performed. Switch 44 is connected only to devices that receive operating characteristic values of the internal combustion engine. When this operating characteristic value changes, the switch 44 is closed. This switch 44 remains in its closed position until either the notch reappears or the counter state reaches zero again so that no delay adjustments are made.

The operation of such a circuit arrangement is illustrated by way of example in FIG. In this figure, time is plotted on the horizontal axis and ignition angle is plotted on the vertical axis. When the notch appears, the ignition angle is adjusted in a step-by-step manner until the notch disappears. The ignition angle set at the position where the notch disappears is maintained, and the influence of other adjustments, such as, for example, pressure reduction adjustments, is not taken into account. If the engine speed or the load changes and the knock no longer appears, the ignition angle is adjusted forward again in slow steps. This adjustment process is interrupted as soon as early adjustment is no longer possible or a new notch appears.

FIG. 7 shows a gate period generation circuit which is advantageously used in an anti-knock device of the construction described above. A signal proportional to the rotational speed is generated in counter 50 and supplied to counters 51 and 52. Counters 50, 51 and 52 are connected to clock generator 53. The output of counter 51 is connected to the set input of flip-flop 54. Furthermore, the output of the counter 51 is connected to the reset input of a flip-flop 55. The output of counter 52 is connected to the reset inputs of flip-flop 54 and flip-flop 56. The output of flip-flop 54 is coupled to evaluation processing circuit 28 of the knock signal generator. At input 57, a rotational speed pulse is applied which is supplied to the inputs of AND gates 58 and 59, respectively. Another negative input of AND gate 58 is connected to the output of counter 51 , and a negative input of AND gate 59 is connected to the output of counter 52 . The input terminal 57 is further connected to the counter 50 via a negative circuit 60.
is connected to the transfer input terminal of the

Counter 50 has the same function as counter 35 shown in FIG. A signal proportional to the engine speed is input to the counter 50. A pulse is applied from clock generator 53, and during the transfer pulse duration derived from the ignition pulse, the clock
A pulse is provided to a counter. Therefore, the third
When using the circuit shown in the figure, the counter 50
is not necessary, and the counting state counted by the counter 35 can be used. The counting state of counter 50 is transferred to counters 51 and 52. Input end 5
When the ignition pulse appears at 7, this pulse passes through AND gate 58 to flip-flop 55.
is supplied to set the flip-flop. The same is done for flip-flop 56 via AND gate 59. Counters 51 and 52 then count backwards (i.e., perform a decrementing count) of the accumulated count states. What is important here is that the clock sequence for counter 51 is faster than the clock sequence for counter 52. Counter 51 therefore reaches state zero earlier than counter 52. When counter 51 reaches state zero, flip-flop 54 is set. This means the gate will open. When counter 52 reaches the zero state with a slight delay, flip-flop 54 is reset and the gate is closed again. Only when the counting state of the counter 50 is read into the counter 51, the AND gate 58 is opened and the input end 57 is coupled to the flip-flop 55. Furthermore, according to this circuit configuration, flip-flop 55 is in a reset state, thereby causing counter 5
1 cannot perform backward counting independently. Input end 57
flip-flop 5 only after a signal is applied to
A set of 5 is made and the flip-flop is reset as soon as the count state zero is reached. As long as counter 51 remains in the zero state, reading in new signals is not possible. AND gate 59 and flip-flop 56 serve the same function.

The circuit described above can be easily integrated. In particular, since some of the components are common to the circuit shown in FIG. 3, this circuit can be used particularly well as the gate period generating circuit 29.

[Brief explanation of drawings]

FIG. 1 shows one embodiment of a control device for shifting the ignition point when a knock occurs in an internal combustion engine;
The figure shows a device controlled in dependence on other operating parameters of the internal combustion engine, FIG. 3 shows a specific embodiment of the device shown in FIG. 1, and FIGS.
5 is a pulse signal diagram for explaining the operation of the device shown in the figure; FIG. 5 shows a modification example for using the device shown in FIG. 3 as a control device; and FIG. 7 is a graph illustrating an example in which the ignition angle is adjusted by using the ignition angle, and FIG. 7 is an embodiment of the gate period generating circuit according to the present invention. 10...Engine, 11,27...Knock signal generator, 12,20...Ignition pulse generator, 15,38
...multiplier, 13, 14, 16, 31, 33, 3
5, 50, 51, 52... Counter, 17, 23... Delay circuit, 21... Pulse shaper, 24, 60... Not circuit, 25... Frequency divider, 26, 30, 54, 55,
56...Flip-flop, 28...Evaluation circuit, 2
9... Gate period generation circuit, 22, 34... AND circuit, 31, 32, 53... Clock generator, 36,
37...memory, 40,58,59...and gate, 44...switch.

Claims (1)

[Claims] 1. An ignition pulse generator and a first counter,
The first counter is connected to a knock signal generator and increases its counting state when a knock signal is generated;
A further counter 14, connected to the ignition pulse generator 12, 20, in a device for shifting the ignition point of an internal combustion engine in the event of a knock, the counting state of which decreases in the event of a change in the operating state of the internal combustion engine;
35, the other counter stores a value inversely proportional to the number of rotations, and the first counter 1
By multiplying 3, 33 by the counting state present at the output of the further counter 14, 35, a product is formed which is a measure of the displacement of the ignition point and is read into the third counter 16, 31; and the third counter 1
Device for shifting the ignition point of an internal combustion engine, characterized in that on the output side of 6, 31 a shifted ignition pulse is output which can be used directly for controlling a conventional ignition system. 2. The device according to claim 1, wherein the displacement of the ignition point is determined by the time until the third counter 16, 31 reaches a predetermined value. 3. Device according to claim 1 or 2, in which the value of another counter is stored in the memory 36. 4. Any one of claims 1 to 3 in which the ignition timing is adjusted in the direction of delay as the value of the product of the counts of the first counter 13, 33 and another counter 14, 35 increases. The device described in. 5 first counter 13, 33 and another counter 14,
5. A device according to claim 1, wherein the product of 35 counts is incremented by a predetermined value before being read into the third counter 16,31. 6 Multiplication is performed by multipliers 15 and 38, and the result is intermediately stored in memory 37. Claim 1
The apparatus according to any one of Items 1 to 5. 7 Another counter 14, 35 and third counter 1
Claims 1 to 6 in which the counting pulses for 6, 31 are taken from a clock generator.
Apparatus according to any of paragraphs. 8. The device according to any one of claims 1 to 7, wherein the counting state of the first counter 13, 33 is decreased more slowly than its increase. 9. The device according to any one of claims 1 to 8, wherein a blocking device 34 is provided to prevent the first counter 33 from falling below a predetermined value. 10 Device 40 for decreasing the counting state of the first counter when the operating parameters of the internal combustion engine 10 change
9. A device according to any one of claims 1 to 8, wherein the device is provided with: 11. A gate period generating circuit 29 is connected downstream of the knock signal generators 27 and 28, and the gate period generating circuit passes the knock signal for a predetermined period.
Apparatus according to any of paragraphs. 12 The gate period generation circuit 29 includes two counters 5 into which signals proportional to the rotational speed of the internal combustion engine are read.
1. Apparatus according to claim 11, having a diameter of 1.52. 13 The two counters 51, 52 are decremented by a predetermined clock, and when one counter 51 reaches the predetermined counting state, it opens the gate, and the other counter 52 13. The apparatus of claim 12, wherein said gate is closed when a predetermined counting condition is reached. 14 The clock frequencies of the two counters are different, and when the counting state of one counter 51 reaches zero, the gate is opened and the clock frequency of the other counter 51 is different.
14. The apparatus of claim 13, wherein the gate is closed when the count state of 2 reaches zero. 15. The device according to any one of claims 11 to 15, wherein the gate period generating circuit 29 is controlled by an ignition pulse.