JPS6079166A - Ignition timing control device of internal-combustion engine - Google Patents

Abstract

PURPOSE:To invariably adjust the ignition timing to an optimum position by determining the ignition timing displacement indicating the mixing ratio of regular gasoline and premium gasoline based on the detection result of knock occurrence by a knock sensor. CONSTITUTION:The presence of knock occurrence is judged by a knock judging section 2 based on the output signal of a knock sensor 1, the ignition timing displacement is determined by an ignition timing displacement determining section based on the output of the judging section 2, and the output value is stored in a memory section 4. The ignition timing displacement determining section 3 has an integrator 31, a reset circuit 32, and an adder 33, and adds the output value of the integrator 31 reset every ignition timing to the output value of the peak hold circuit 41 of the memory section 4. Then, the added output is outputted from the peak hold circuit 41 to hold the peak value. When the output value of the peak hold circuit 41 is increased, the ignition timing is delayed by an ignition timing phase-shifter 6 and displayed on a display unit 9.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention detects knocking, determines the mixing ratio of regular gasoline and premium gasoline, shifts the ignition timing accordingly, and displays the mixing ratio to the driver. The present invention relates to an ignition timing control device for an internal combustion engine.

[Prior art]

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.

FIG. 1 shows the ignition timing-output shaft torque characteristics of an internal combustion engine using commercially available regular gasoline and premium gasoline (which also has a higher octane number than regular gasoline).

Point A in FIG. 1 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.

According to FIG. 1, since the ignition timing can be advanced to point B when premium gasoline is used, it is possible to improve the output shaft torque compared to when regular gasoline is used.

Further, 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 FIG. 2, the interval between the ignition timing characteristic A and the ignition timing characteristic B shows a substantially constant value with respect to the rotational speed.

From the above, in an internal combustion engine with such characteristics, when regular gasoline and premium gasoline are mixed or used in conversion, the engine can be improved by advancing the ignition timing according to the mixture ratio of regular gasoline and premium gasoline. It becomes possible to improve the output of

By the way, in conventional ignition timing control devices, the ignition timing characteristics are set only for a predetermined gasoline, such as regular gasoline. could not be expected, and the ignition timing had to be reset to the advanced side in some way.

In particular, when using mixed gasoline, depending on the mixing ratio of regular gasoline and premium gasoline, A
There is a knock limit point between B and B, and the advance limit changes, so it was not easy to reset the ignition timing.

In addition, the engine operator did not know the mixture ratio of regular and premium gasoline in use, and did not know how much to shift the ignition timing.

[Summary of the invention]

Therefore, this invention was developed in view of the above points, and uses a knock sensor to detect the occurrence of knock, and the detected value indicates the mixing ratio of regular gasoline and premium gasoline in use. By determining the amount of ignition timing displacement and setting the ignition timing to the advanced or retarded side accordingly, the mixture ratio of regular gasoline and premium gasoline is automatically determined and the ignition timing is set at the optimal position. The present invention proposes an ignition timing control device for an internal combustion engine that can adjust and display the gasoline mixture ratio to the engine driver.

[Embodiments of the invention]

Embodiments of the ignition timing control device for an internal combustion engine according to the present invention will be described below with reference to the drawings.

FIG. 3 is a block diagram showing the configuration of one embodiment.

In FIG. 3, reference numeral 1 denotes a knock sensor that is attached to the engine and detects knocking of the engine.

Further, reference numeral 2 denotes a knock determination unit that determines whether knock has occurred from the output signal of the knock sensor 1, and a bandpass filter 21. It is composed of a noise level detector 22 and a comparator 23.゛Band pass filter 210 input iU/connected to output terminal of sensor l, output terminal of band pass filter 21 is connected to one comparison input terminal of comparator 23 and noise level detector 2
Connected to the input terminal of 2. The output terminal of the noise level detector 22 is connected to the other comparison input terminal of the comparator 23.

Reference numeral 3 denotes an ignition timing displacement determination unit that calculates from the output of the knock determination unit 2 and determines the displacement amount of the ignition timing, and an integrator 31
, a reset circuit 32, and an adder 33.

The input end of the integrator 31 is connected to the output end of the comparator 23,
The output terminal of the integrator 31 is connected to one input terminal of the adder 33.

Further, the integrator 31 has a reset terminal for resetting the integrated value to zero, and this reset terminal is connected to the output terminal of the reset circuit 32.

4 is a storage unit that stores and holds the output value of the ignition timing displacement determining unit 3, and includes a peak hold circuit 41 and a reset circuit 4.
Consisting of 2.

The input terminal of the peak hold circuit 41 is connected to the output terminal of the adder 33, and the reset terminal provided in the peak hold circuit 41 is connected to the reset circuit 42. The output terminal of the peak hold circuit 41 is connected to the other input terminal of the adder 33, and is added to the output value of the integrator 31 by the adder 33.

9 is a display section, the input terminal of which is connected to the peak hold circuit 4
Connected to the output terminal of 1. In addition, the peak hold circuit 4
The output terminal of No. 1 is also connected to a control input terminal of an ignition timing phase shifter 6, which will be explained later.

5 is a reference ignition timing signal generator that generates a reference ignition timing signal for the engine; 6 is a reference ignition timing signal generator that converts the output signal of the reference ignition timing signal generator 5 into the value of the output of the storage section 4 (output of the peak hold circuit 41); This is an ignition timing phase shifter that controls the phase shift accordingly.

Reference numeral 7 denotes a switching circuit that energizes the ignition coil 8 on and off in synchronization with the output signal of the ignition timing phase shifter 6, and generates a high voltage necessary for igniting the internal combustion engine. The output of the ignition phase shifter 6 is also connected to the input of the reset circuit 12.

Next, the operation of the ignition timing and control device for the internal combustion engine of the present invention constructed as described above will be described with reference to FIGS. 4 and 5. FIG. 4 is an operational waveform diagram of each part of the knock discrimination section 2.

A knock sensor is a generally well-known vibration acceleration sensor that is attached to an engine's cylinder block, etc., and converts the engine's mechanical vibrations into electrical signals.
) Outputs a vibration wave signal as shown in ().

The band bass filter 21 passes only the knock-specific frequency component from the output signal of the knock sensor, suppresses noise components other than knock, and outputs a good signal of 87 as shown in A of FIG. 4(b). .

The noise level detector 22 can be composed of, for example, a half-wave rectifier circuit, an averaging circuit, an amplifier circuit, etc., and performs half-wave rectification and averaging of the output signal of the band-pass filter 21 (a in FIG. 4(b)). The output signal of the bandpass filter 21 (Fig. 4(b)
It outputs a DC voltage that is higher than the noise component in (a) and lower than the knock component.

The comparator 23 receives the output signal of the bandpass filter 21 (the fourth
A) in Figure (b) and the output signal of the noise level detector 22 (
When knocking does not occur (part C in Fig. 4), the output signal of the bandpass filter 21 (a in Fig. 4(b)) is detected by the noise level detector. On the other hand, when a knock occurs (the fourth section), the output signal of the bandpass filter 21 (the opening in FIG. 4(b)) is not exceeded, so nothing is output. (b)-a)
exceeds the output signal of the noise level detector 22 (the opening in FIG. 4(b)), so a pulse train is output as shown in FIG. 4(c).

Therefore, the occurrence of knocking can be determined based on the presence or absence of the output of the pulse train (FIG. 4(C)) from the output of the comparator 23.

FIG. 5 shows the operation of each part of the ignition timing displacement determination section 3, the storage section 4, and the ignition timing phase shifter 6. The integrator 31 integrates the pulse train (FIG. 5(a)) output from the comparator 23.

On the other hand, the reset circuit 32 receives the output signal (ignition signal) of the ignition timing phase shifter 6, outputs a pulse as shown in FIG. Reset to . Therefore, the output of the integrator 31 is the fifth
As shown in Figure (b), the output voltage rises when knocking occurs, resulting in a waveform that is reset at each ignition timing.

Next, the adder 33 outputs the output value of the integrator 31 (see FIG. 5(b)).
) and the output value of the peak hold circuit 41, which will be explained later, are added.

However, the output value of the peak hold circuit 41 to be added is the value before addition, and this value is held inside the adder 33 while the value of the integrator 31 is input.

A peak hold circuit 41 holds the peak value of the output of the adder 33. FIG. 5(d) shows the output waveform of the peak hold circuit 41.

The reset circuit 42 outputs a high level pulse when starting the engine, and the output pulse of the reset circuit 42 is shown in FIG. 5(e).

First, when the engine is started, the peak hold circuit 41 is reset by the beam set circuit 42, and the output becomes zero level. Then, when a knock occurs in the engine and a pulse train appears at the output terminal of the comparator 23 as shown in the fifth factor (a), the integrator 31 integrates the pulse train (see FIG. 5(b)), and the adder 33 adds the integrated output value of the integrator 31 and the output value of the peak hold circuit 41 before addition, and the peak hold circuit 41 holds the peak value of the output of the adder 33 (the fifth
Figure (d)).

The above operation continues until knocking no longer occurs in the engine, and the output value of the peak hold circuit 41 increases.

On the other hand, the ignition timing phase shifter 6 controls the phase of the input signal to be retarded in accordance with the control voltage.

The ignition timing phase shifter 6 is a well-known technique in ignition timing control devices, and therefore will not be described here.

The reference ignition timing signal generator 5 detects the rotation of the crankshaft of the engine and outputs a signal indicating when to ignite, and is, for example, an ignition signal generator built in a distributor.

The ignition timing characteristics of the reference ignition timing signal generator 50 are set according to the engine speed and load, and regarding the engine speed, the ignition timing characteristics are set to B in FIG. 2. The output signal of the reference ignition timing signal generator 5 is shown as shown in FIG. 5(f), and is input to the ignition timing phase shifter 6. Then, the output of the peak hold circuit 41 is input to the control voltage input of the ignition timing phase shifter 6, and the output signal of the reference ignition timing signal generator 5 is retarded in accordance with the output value of the peak hold circuit 41. . The output signal of the ignition timing phase shifter 6 is shown in Figure 5 (b).
).

Now, when the output of the peak hold circuit 41 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, so that the actual The ignition timing characteristic in ignition remains the same as the ignition timing characteristic of B in FIG.

In addition, knocking occurs in the engine, and the ignition timing displacement determination unit 3
calculates the amount of retard phase shift, and when the output value of the peak hold circuit 41 increases, the ignition timing phase shifter 6 changes as shown in FIG. 5 (b)).
As shown in , the output signal of the reference ignition timing signal generator 5 (
5(f)) is retarded in phase in accordance with the output value of the peak hold circuit 41. Therefore, the ignition timing characteristic in actual ignition is as shown by the broken line shown in the ignition timing characteristic in FIG. 2C.

Therefore, if premium gasoline is used, the second
Since knock does not occur in the ignition timing characteristic shown in characteristic B in the figure, the ignition timing is not retarded and the characteristic shown in B in FIG. 2 remains unchanged.

Further, when regular gasoline or a mixture of regular and premium gasoline is used, the ignition timing characteristic B in FIG. 2 is in the range where knock occurs, so knock occurs in the engine.

As described above, knock is detected by the knock discriminator 2, the ignition timing displacement determining section 3, the storage section 4, and the ignition timing phase shifter 6, and the ignition timing is retarded. Or, even when using a mixture of regular and premium gasoline, the ignition timing characteristics do not cause knocking (as shown in the ignition timing characteristics of A in Figure 2 when using regular gasoline, and as shown in Figure 2C when using a mixture of regular and premium gasoline). The ignition timing is fixed to the ignition timing characteristics).

Here, the output value of the peak hold circuit 41 becomes a lower value as the mixing ratio of premium gasoline becomes larger, and becomes a higher value as the mixing ratio becomes smaller (that is, as more regular gasoline is mixed). Therefore, the peak hold circuit 41
The output value corresponds to the result of determining the mixture ratio of premium gasoline and regular gasoline.

Therefore, by inputting the output of the peak hold circuit 41 to the display section 9, the mixture ratio of premium and regular in the gasoline being used can be displayed to the engine driver.

FIG. 6 shows an example of the display board of the display section 9. The display board 9 is installed on a meter panel or the like in the driver's cabin.

Regular R and Premium P for easy recognition by drivers
Character display and different color display CP.

OR is not applied.

Further, a voltmeter or an ammeter is used for the display section 9, and its pointer 9a is adjusted to correspond to the output value of the peak hold circuit 41, that is, the mixing ratio.

〔Effect of the invention〕

As explained above, according to the ignition timing control device for an internal combustion engine of the present invention, when regular gasoline and premium gasoline are mixedly used, the knock sensor detects the occurrence of knock, and based on this, the reference ignition timing is set. By calculating the amount of timing displacement, it is possible to automatically switch the reference ignition timing characteristic to the optimum ignition timing without knocking in regular-premium mixed gasoline.

Furthermore, by displaying the output value of the storage section that stores the ignition timing displacement amount, there is an effect that the mixture ratio of regular and premium in the gasoline being used can be displayed and the engine driver can recognize it.

[Brief explanation of the drawing]

FIG. 1 is an engine ignition timing versus output shaft torque characteristic diagram, FIG. 2 is an engine rotation speed versus ignition timing characteristic diagram, and FIG. 3 is a block diagram showing an embodiment of an ignition timing control device for an internal combustion engine according to the present invention. 4 is an explanatory diagram of the operation of the knock discrimination section in the ignition timing control device for the internal combustion engine, and FIG. 5 is an ignition timing displacement determining section, storage section, and ignition timing phase shift in the ignition timing control device for the internal combustion engine. FIG. 6 is a diagram showing an example of the display board of the display section in the ignition timing control device for the internal combustion engine. 1... Knock sensor, 2... Knock discrimination section, 3...
・Ignition timing displacement determining unit, 4... Storage unit, 5... Reference ignition signal generator, 6... Ignition timing transfer device, 7...
Switching circuit, 8... Ignition coil, 9... Display section. Agent Masuo Oiwa Procedural amendment (voluntary) Mr. Commissioner of the Japan Patent Office 1. Indication of the case: Japanese Patent Application No. 58-188094 2. Name of the invention: Ignition timing control device for internal combustion engine 3. To the representative of the person making the amendment: Hitoshi Katayama. 4. Agent 5: Each column of the detailed description of the invention and the brief description of the drawings in the specification subject to amendment. 6. Contents of amendment (1) Page 7, line 7 of the specification: “Ignition is by phase shifter” t- “Ignition timing by phase shifter” is corrected. (2) Correct "12..." in line 8 of the same page to "32...". (3) Delete "as shown" on page 13, lines 9-10. (4) On page 16, line 1, "Ignition timing shifter" is corrected to "Ignition timing phase shifter."that's all

Claims (1)

[Claims] A knock sensor that detects knock in the internal combustion engine, a knock determination means that determines whether knock has occurred based on the output of this knock sensor, and a phase shift amount that is calculated from the output of this knock determination means and determines the phase shift control amount of the ignition timing. determining means, storage means for storing the output of the phase shift amount determination means, ignition timing displacement means for displacing the reference ignition timing of the engine in accordance with the output of the storage means, and output level of the storage means being adjusted to the engine driver. An ignition timing control device for an internal combustion engine, comprising display means for displaying.