JPS60104775A - Ignition timing controller for internal-combustion engine - Google Patents

Abstract

PURPOSE:To prevent a knock from occurring, by selecting the reference ignition timing of an engine automatically according to working conditions of gasoline in types different in an octane number each, while controlling the ignition timing with delayed timing control when knocking happens at the ignition timing before and after ignition timing selection. CONSTITUTION:On the basis of a vibration signal generated out of a knock sensor 1, the presence of knock generation is discriminated at a knock discriminating part 2, and in time of knock discrimination, a judging signal for ignition timing selection is outputted at an ignition timing selection discriminating part 3 at a time when the specified number of knocks is generated within a specified period of time. Then, this judging signal is inputted into an ignition timing phase shifter 6 via a memory part 4, and a reference ignition timing signal generating part 5 is shifted in its phase to delayed timing control at a time, for example, when the knock is generated by use of regular gasoline after using a premium one. In addition, when the knock generated before and after ignition timing selections, with the output of a delayed timing control voltage generating part 9, the ignition timing is controlled for the delayed timing control via a combined part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an ignition timing control device for an internal combustion engine.

It is well known that the octane number of gasoline has a strong correlation with knock resistance in internal combustion engines.

In other words, gasoline with a high octane rating is less likely to cause a knock. Figure 1 shows the ignition timing-output shaft torque characteristics at t for an internal combustion engine using commercially available regular gasoline and grammium gasoline (which has a higher octane number than regular gasoline). Point A is the knock limit point when regular gasoline is used, and point B is the knock limit point when premium gasoline is used. Knock occurs when the ignition timing is advanced beyond the knock limit point. 1st
According to the diagram, when using premium gasoline, the ignition timing I
Since the angle can be advanced to point B, it is possible to increase the output shaft torque when using regular gasoline. FIG. 2 is an ignition timing characteristic diagram showing the ignition timing at points A and B in FIG. 1 with respect to the rotational speed of the internal combustion engine.

In an internal combustion engine with such characteristics, when converting from regular gasoline to premium gasoline, engine output can be improved by advancing the ignition timing by a certain angle.

[Takumi technology]

By the way, in the conventional ignition timing control device, the ignition timing characteristics are set only for a specified gasoline (for example, regular gasoline), so when using premium gasoline, the direction of the engine's output cannot be expected as it is, and some I had to reset the ignition timing to the advanced side using the method. In addition, the knock limit points at points A and B in Figure 1 vary depending on the environmental conditions during engine operation, such as temperature and humidity. There was a risk of knocking.

[Summary of the invention]

The present invention has been made in view of the above points, and uses a knock sensor to detect the occurrence of knock, and based on the detected value, determines whether the gasoline in use is regular gasoline or premium gasoline.1. By setting the ignition timing to the advanced or retarded side,
The standard ignition timing is automatically switched according to the type of gasoline, and if knocking occurs at the standard ignition timing before or after switching, the ignition timing is retarded (retarded) according to the occurrence of knock. ) to suppress the occurrence of knocking.

FIG. 8 shows a first embodiment of the invention. In FIG. 8, (1) is a knock sensor that is attached to the engine and detects knocking of the engine. (2) is the knock sensor (1)
This is a knock determination section that determines whether or not a knock has occurred from the output signal of the 4 seconds. The input of the bandpass filter (2) is connected to the knock sensor (1) and the output is connected to one of the comparators (to the human power and noise level detector). The output of the noise level detector) is then connected to the other comparator of the comparator (2). (3) is calculated from the output of the knock discriminator (2).
This is an ignition timing switching determination section that determines whether or not ignition timing switching is necessary, and it generates pulses &? = r, 3], l S counter u4
Consists of N timers. (The power of the lus generator Oυ is connected to the output of the comparator -, and the output is connected to the old enemy power of counter 0'4. Also, the timer is connected to the reset power of counter 4. (4) is a storage unit that stores the mode of the output of the ignition timing switching determination unit (3) (output of the counter 4), and is composed of a flip-flop F/l″ and a reset circuit←4. The set input of the circle is connected to the output of the counter c'4, and the reset input is connected to the reset circuit (6).

(9) is a retard control voltage generator, whose power is connected to the output of the comparator). Q(I is a synthesis unit, which is composed of an adder (101) and a timer (IO illusion).
The device 0o1) has two input terminals r, one of which is connected to the output of the free-lag flop 1411, and the other is connected to the retard side (goods).
Connected to the output of the voltage generator (9). Timer (1o2
) is connected to the output of the 7-lip flop 141), and the output is connected to the reset terminal of the retard control j4 voltage generator (9). On the other hand, <bl is a reference ignition timing signal generator that generates the semi-ignition timing number of the engine, and (6) is a reference ignition timing signal generator (combining part Q
This is an ignition timing phase shifter that shifts the phase according to the output of the adder (101). (7) is the ignition timing phase shifter (6)
The ignition coil (8) is connected in synchronization with the output signal of the ignition coil (8). [f
This is a switching circuit that is connected to the engine and generates the high voltage necessary to ignite the internal combustion engine.

Next, the operation and operation of each part will be explained. Figure 4 shows the knock discrimination section (
2) shows the operation of each part. The knock sensor (1) is a generally well-known vibration acceleration sensor that is attached to the engine's cylinder block, etc., and converts the mechanical vibration of the engine into an electrical signal, and generates vibrations as shown in Figure 4 (a). Outputs a wave signal. The bandpass filter Qυ is the knock sensor (
By passing only the knock-specific frequency component from the output signal of step 1) and suppressing noise components other than knock, the output signal shown in Fig. 4(b)
), a signal with a good S/N ratio -υ- is output as shown in ('I). For noise level detector), for example, a half-wave rectifier circuit,
It can be composed of an averaging circuit, an amplifying circuit, etc., and the output signal (M:
(a)) is converted to a DC voltage level by half-wave rectification and averaging, and amplified at a predetermined amplification degree.
As shown in the figure, a DC voltage is output which is higher than the noise component of the output of the band pass filter Qυ (No. 8 ((a) in Fig. 4(b)) and lower than the knock component.
b) is the output signal of the bandpass filter button υ (Fig. 4(b)
) and the output signal of the noise level detector (2) ((b) in Fig. 4(b)), and if no knock occurs (part C in Fig. 4), the band pass filter is Since the output signal of (c) ((a) in Figure 4(b)) does not exceed the output signal of noise level detector (2) ((b) in Figure 4(b)), nothing is output. , on the other hand, if a knock occurs (the fourth
The output signal of the bandpass filter Qυ (the fourth
Since (a) in Figure (b) exceeds the output signal of the noise level detector (2) ((B) in Figure 4(b)), Figure 4(C)
) Outputs a pulse train as shown in ().

Therefore, the pulse train from the output of the comparator (FIG. 4(C)
)) The occurrence of knocking can be determined by the presence or absence of the output.

FIG. 5 shows the operation of the troughs other than the knock discriminator (2).

The pulse generator 9 outputs pulses as shown in FIG. 5(d) in response to the pulse train (FIG. 5(C)) output from the comparator. In other words, the pulse generator o outputs one pulse in response to knock occurrence for one ignition.

The output pulses of the pulse generator 6υ are counted by R'IrIt'l
1, and the valley within the number is shown in FIG. 6(e). The timer outputs a pulse at predetermined intervals as shown in Figure 5 (fl), and the pulse causes the counter-Z
Reset the count value to zero. Further, as shown in FIG. 5(g), the output of the at counter 0 becomes a high level when the count value of the counter oa exceeds a predetermined value (count value 8 in FIG. 5). That is, the ignition timing switching determination section (3) outputs a high level signal when a predetermined number of knocks occur within a predetermined time. This calculates the knock occurrence rate using the method described above, and as a result determines whether or not ignition timing switching is necessary.

The reset circuit (44 outputs a high level pulse when starting the engine, and the output pulse of the reset circuit i44 is shown in FIG. 5 (11).
1) is set when the output of the @1 digit circuit is at a high level (the output of the free lag flop @phantom becomes a high level), and is reset when the output of the 7-bit circuit @Hun is at a high level.

Figure 5 (i) shows the operation of the output of this flip-flop @1).
). First, when the engine is started, the flip 70 knob is reset by the reset circuit and the first output becomes a low level. In other words, the mode becomes a mode (advanced angle mode) in which the ignition timing is not changed. The output of 1 counter 0 sand is shown in Figure 5 (g
When outputting a high level like l, flip frog 1
The output of 411 switches to high level. In other words, the mode is set to switch the ignition timing (ii! angle mode). From then on, the retard mode is maintained until the engine stops. Also, naturally, if the output of the counter (counter) does not output a high level after the engine starts, the output of the Norilag Frog @ Phantom will remain at a low level (advanced angle mode).

In addition, the retard side voltage generator (9) is, for example, an integrating circuit (
5 (C) is output from the comparator), the pulse train is integrated, and
Increase the output voltage like UJ. In addition, if the pulse train is not output from the comparison Hg), the output of the retard control voltage generator (9) will gradually decrease at a constant speed.Then, the ignition timing will be brought to the knock limit point Generates in real time the retard side AL11 voltage that retards the angle up to 1 to suppress the occurrence of knock. ).The output of the adder (1ol) is shown in section 51). Also, the timer (102) is connected to the Norilag frog 14.
When the 1I output is reversed from a low level (advanced angle mode) to a still level (retarded angle mode), a pulse is output for a predetermined period of time as shown in FIG. 5 (1). This voltage is applied to the reset terminal of the retard control voltage generator (9), and the output voltage of the retard control voltage generator (9) is reset to zero level as shown in FIG. 5U. Therefore, the output of the adder (101) is as shown in Fig. 6 (
It looks like the solid line of kl. If ``Furi Ruff'' flop 1
411 to the retard side 1, the retard control voltage generator (9
) If the outputs of To prevent retardation or to use a retardation control voltage generator (9
) is reset to zero level so that the output of 1,1 is not added.

On the other hand, the 1-ignition IIU phase phase shifter (6) sets the control voltage to LL and controls the phase of the input signal to be shifted to the retard side.

After this ignition timing, the ignition timing will be turned off for the 4.
- This is a well-known technique in devices, and its explanation will be omitted here. A reference ignition timing signal generator (51 detects the rotation of the engine crankshaft and outputs a signal indicating the timing to ignite; for example, the ignition signal generator used internally in the distributor is ,)cormorant. The ignition timing characteristics of this reference ignition timing signal generator (5) are set depending on the engine speed and load, and regarding the speed, see Figure 2 (
B).

The output a of the reference ignition timing signal generator (5) is shown in Figure 5 (
m) and is input to the ignition timing phase shifter (6). The output of the 1 adder (101) is input to the control (2) voltage input of the ignition timing phase shifter (6), and the output of the adder (101)
) according to the output voltage of the reference ignition timing signal generator (5)
The output signal of is phase shifted. The output signal of the ignition timing phase shifter (6) is shown in FIG. 5(n). Now flip-flop I
When the output of II is at a low level (advanced angle mode) and the output of the retard control 141 voltage generator (9) is at zero level,
The ignition timing phase shifter (6) does not perform a phase shifting operation, and the output signal of the reference ignition timing signal generator (5) appears as it is at its output.
(Fig. As shown in FIG. 5 (n), the ignition timing phase shifter (6) retards the output signal (FIG. 6 (j)) of the reference ignition timing signal generator (5) by a predetermined angle. Compare with each other. Therefore, the ignition timing characteristics in actual ignition are as shown in FIG. 2 (4). In addition, if knocking occurs even after switching the ignition timing, the ignition timing will be further retarded than in the second section. Therefore, if premium gasoline is used, as shown in Figure 2 (
In the ignition timing characteristics shown in B), there is no knock that would require switching the reference ignition timing, so the ignition timing does not switch and the characteristics shown in Figure 2 (uniform) remain. When using recura gasoline, knocking occurs in the engine (because the ignition timing characteristics shown in FIG. 2(B) are in the range where knocking occurs). Then, a knock discrimination section (2), a bird ignition timing switch judgment section (3), a storage section (4)
The knock is detected by the ignition timing phase shifter (6), the ignition timing is switched to the retarded side, and the ignition timing is fixed to the ignition timing characteristic shown in FIG. 2 (5). If knock occurs even when the ignition timing is zero, the retard control voltage generator (9) and the synthesis unit (tls ignition timing phase shifter (6) adjust the 31Jl at the time of ignition to the knock limit point. delay until.

Incidentally, in the first embodiment, the reference ignition signal is switched by retarding the phase according to the output of the storage section (4), but two reference ignition timing signals having different ignition timing characteristics are stored in the storage section (4). ), which will be described below as a second embodiment.

FIG. 6 shows a block diagram of a second embodiment of the present invention. In FIG. 6, the same shape as in FIG. 8 indicates the same part. (hereinafter ILOMα
Q), <11 is a second ignition timing characteristic storage section (hereinafter referred to as ROM), and as shown in FIG. Ignition timing data is stored in each address. Figure 7 (A) shows fLOMQtl data, which is set for regular gasoline.
Figure) is the data in ROM (b) and is set for premium gasoline, and is located on the advance side than in the 7th section. (
2) is the data selector, ROMQQ and ROM(
Input the data of (b) and the output mode of the storage unit (4),
Depending on the output mode of the storage unit (4), it outputs data of ILOMQQ or ROM (lυ. (2) has the same function as the timer (102) in the first embodiment) and is a timer connected in the same way. a4 is an A/D converter that converts the output voltage of the retard control voltage generator (9) into a digital quantity;
This is a non-subtractor that subtracts the output value of the D converter α→. Of
9 is a crank angle sensor that detects the crank rotation angle of the engine, and aη is a pressure sensor that detects the intake air pressure of the engine. (To) is an ignition timing calculator that calculates the engine speed from the output signal of the first crank angle sensor α, detects the engine load condition from the first pressure sensor α, and uses those speeds and loads to calculate the engine speed. The determined value is converted into an address value, and the address value is output to ROMαQ and ROMQη. In addition, the 1 ignition timing calculator (G) reads the output data of the subtractor (C), calculates the ignition timing from the output data of the crank angle sensor (the subtracter uses the output signal of 1 as a reference), and outputs the ignition signal. Output to the switching circuit (7).

Next, the operation of the second embodiment will be explained. The knock determination unit (2), ignition timing switching determination unit (3), storage unit (4), and retard control voltage generator (9) are the same as those in the first embodiment. Now, when premium gasoline is used), the output of the memory section (4) remains at a low level (advanced angle mode). Therefore, the data selector (6) outputs the data of ROMQυ in the low level output mode of the storage section (4). In other words, the ignition timing characteristic shown in FIG. 7(B) is set as the reference ignition timing. If knock does not occur at that ignition timing, the retard control voltage generator (9) and the A/D
Since the output of converter α4 is at zero level, 1 subtraction u (1
An output of 0 outputs the output data of the data selector directly to the ignition timing calculator.

In addition, when a knock occurs to the extent that the 1 ignition timing switching determination section (3) does not require switching, the 1 retard side 1 fill voltage generator (9) outputs a voltage due to the occurrence of knock, and the A/D
The friend converter α converts the output voltage of the retard control voltage generator (9) into a digital quantity, and the 1 subtracter (to) converts the output voltage of the retard control voltage generator (9) to the data selector (
The output value of A/D converter α4 is subtracted from the output value of 2). Therefore, the data output from the subtracter) is ROM
The data obtained by subtracting the angle (θR) corresponding to the output of the retard control voltage generator (9) from the H data (θB) is the data (θB-〇R), which is then sent to the ignition timing calculator) as shown in Figure 7. (B
) An ignition signal retarded from the reference ignition timing by an angle θR corresponding to the occurrence of knock is output to suppress the occurrence of knock.

In addition, when using regular gasoline, the storage section (
The output of 4) is the quotient level (retard mode) K, and the 1 data selector (6) outputs the data of ILOMα1, that is, the data according to the ignition timing characteristics in the 7th section. Then, in the same way as when using premium gasoline above, use the ignition timing calculator)
is the RUMQQ data (θA) if no knock occurs.
If a knock occurs, read the -0R data.

As described above, according to the second embodiment, the standard ignition timing characteristics are switched to different ignition timing characteristics (within the 7th section and (B)) when premium gasoline is used and when regular gasoline is used, and the standard ignition timing characteristics are also changed. When knock occurs in the reference ignition timing characteristics, the engine is controlled to output an ignition signal retarded than the reference ignition timing in order to suppress the occurrence of knock.

〔Effect of the invention〕

As explained above, according to the present invention, when Reg 2 gasoline and premium gasoline are used interchangeably, it is determined whether it is Reg 2 gasoline or premium gasoline by detecting the presence or absence of knocking with a knock sensor. Furthermore, there is an effect that the reference ignition timing can be automatically switched to regular gasoline or premium gasoline based on the determination result.

In addition, even if knock occurs due to changes in engine conditions during engine operation, the ignition timing can be retarded to the knock limit point in real time. be.

Furthermore, by resetting the retard control voltage generator (9) when one ignition timing is switched to the retard side, there is also the effect that excessive retardation can be prevented.

[Brief explanation of the drawing]

Fig. 1 is an output shaft torque characteristic diagram of the engine, Fig. 2 is an ignition timing characteristic diagram of the engine, Fig. 8 is a block configuration diagram showing the first embodiment of the present invention, and Fig. 4 is a knock discrimination section (2 ), Figure 6 shows the ignition timing switching determination section (3) and the storage section (4).
1. Retard control voltage generator (9) 1. Synthesizing section 001. Ignition timing phase shift 'dD (6) The figure is an ignition timing characteristic diagram in the second embodiment. (1) is a knock sensor, (2) is a knock discrimination unit, (3)
is the ignition timing switching determination unit 1 (4) is the storage unit, (5J is the reference ignition timing (mf generator), (6) is the ignition timing phase shifter, (7
) is a switching circuit, (8) is an ignition coil, (9) is a retard control voltage generator, and α1 is a combining section. Note that the same reference numerals in the figures indicate the same or different parts. Agent Masuo Oiwa Fig. 1 Fig. 2 Fig. 3 Fig. 41KI Fig. 5 Continuation of amendment (voluntary) LJH4H) 15 Showa Ben-yu, Monday, Sun 7; i'+i'FI'+Mr. Secretary 1, Incident display 1-Ylafi 1984-213821
Bow 2, within the name of the invention ignition timing side 11i11 device i3,
Representative for the person making the amendment (Jin Katayama, Department 4, Attorney 5, inventor, patent applicant, or representative other than the above for the application subject to amendment)
person's! l'ld, and the detailed description of the invention in Specification A. 6 Contents of the amendment (1) The furigana of “Groyo Danno” in line 5 of page 2 of the application form has been changed to “
Danno Yoshiaki and another 41℃ correction as requested. (2) Add the following statement to page 4, line 19 of the specification and 2nd of J Ill. [Embodiments of the invention] 7. Request for correction of list of attached documents IJrJj

Claims (4)

[Claims] (1) a knock sensor that detects knock of the internal combustion engine; a knock determination means that determines whether or not knock has occurred from the output of the knock sensor; a calculation is made from the output of the knock determination means;
an ignition timing switching determination means for determining whether or not ignition timing switching is necessary; a storage means for storing the output of the ignition timing switching determination means;
A retard control cape voltage generation means calculates from the output of the knock discrimination means and generates a voltage according to the occurrence of knock, and switches the standard ignition timing of the engine according to the output of the storage means, and also generates the retard control cape pressure. An ignition timing control device for an internal combustion engine, comprising an ignition timing calculation means that retards the ignition timing according to the output of the generation means. (2) The ignition timing calculation means cancels the retard control of the ignition timing by the output of the retard control voltage generation means when the output of the storage means changes to the retard side.
An ignition timing control device for an internal combustion engine according to claim 1. (3) The ignition timing control device for an internal combustion engine according to claim 1 or 2, wherein switching of the reference ignition timing in the ignition timing calculation means is performed by shifting the reference ignition timing. (4) The internal combustion engine according to claim 1 or 2, characterized in that the switching of the reference ignition timing in the ignition timing calculation means is performed by switching between two reference ignition timings having different ignition timing characteristics. Engine ignition timing control device.