JPH03264750A - Ignition timing controller of internal combustion engine - Google Patents

Abstract

PURPOSE:To ensure the optimum ignition timing in all the regions of knocking control by correcting a knocking study value by a correction amount, set by an engine speed, so as to obtain the ignition timing when the engine speed is changed. CONSTITUTION:A knocking study value is referred to a reference means C through an operative condition equal to the actual operative condition by providing a memory means B in which the knocking study value for suppressing knocking is stored in each operational region of an engine. An ignition timing delay amount is set by a delay amount setting means E in accordance with knocking detected by a knocking detecting means D, and further a correction amount, which is increased in accordance with increase of an engine speed detected by an engine speed detecting means F, is set by a correction amount setting means G, respectively. A new knocking study value is set and updated by an update means H from these delay timing amount, correction amount and knocking study value, also ignition timing is corrected by a correcting means I from these knocking study value and delay timing amount.

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to an ignition timing control device for an internal combustion engine.

<Prior Art> Conventional examples of this type of ignition timing control device include the following.

That is, engine operating conditions (e.g. engine speed and engine load)
The ignition timing is set according to the ignition timing, and the ignition plug is activated at the set ignition timing. Furthermore, when non-king occurs in a predetermined high-load operating range, the ignition timing is retarded by a predetermined amount (for example, 1°). Furthermore, when non-knocking does not occur, the ignition timing is advanced as much as possible near the non-knocking limit region to increase engine output.

Furthermore, in Japanese Patent Application No. 1-243378, the applicant stores knock learning values in RAM for each operating range (for example, engine speed and engine load), and sets them based on the detection signal of the knocking sensor. A new knock learning value is obtained from the advance/retard amount and the knock learning (iF) detected from the RAM, and the data in the RAM is updated to the new knock learning value, and the ignition is started based on the new knock learning value. We are proposing a so-called knock learning control that activates the ignition of the tap.

<Problem to be solved by the invention> However, due to the influence of combustion chamber pressure, intake air filling efficiency, etc.
Since the required knock learning value changes even in the same driving range of M, if knock learning control is performed for each driving range, the following problems will occur.

That is, in the area where the operating range of the RAM is the same (arrow area in Figure 5), after obtaining the knock learning value by knock learning control in the high rotation range (point C in Figure 5), When the engine enters the non-knock control area and enters the knock control area again in the low rotation range (center point in Figure 5), ignition timing control is started based on the knock learning value in the high rotation range. Ru.

For this reason, when starting ignition timing control in a low rotation range, the ignition timing is excessively advanced compared to the required ignition timing, resulting in a problem that non-king occurs. Conversely, within the same operating range, if ignition timing is controlled in the high rotation range based on the knock learning value obtained in the low rotation range, the ignition timing will be excessively retarded than the required ignition timing, resulting in insufficient output. There is a problem with this.

The present invention has been made in view of the above circumstances, and provides an ignition timing control device for an internal combustion engine that can ensure optimal ignition timing and suppress non-king even if the operating condition changes in the same operating range. The purpose is to provide.

Therefore, as shown in FIG. 1, the present invention includes an ignition timing setting means A that sets the ignition timing according to the engine operating state, and a knock learning value that suppresses knocking. a storage means B for storing the engine rotational speed and the engine load in correspondence with each other for each operating region; and a retrieval means C for retrieving a knock learning value from the storage means B under the same operating conditions as the actual engine operating state. , a non-king detection means for detecting non-king, a retard amount setting means E for setting a retard amount of ignition timing in order to suppress non-king according to the detected knocking, and an engine rotation speed detection means for detecting the engine rotation speed. Means F and correction amount setting means for setting a correction amount to increase as the engine rotation speed increases according to the engine rotation speed detected when the engine rotation speed changes; an updating means H for setting a new knock learning value from the knock learning value, the searched knock learning value, and the set correction amount, and updating the data in the storage means B to this new knock learning value under the same operating conditions; ignition timing correction means I for correcting the ignition timing by the retard amount and a knock learning value; and ignition control means for igniting the ignition plug J in accordance with the corrected ignition timing.
We prepared the following.

<Operation> Then, the knock learning value is corrected by the correction amount set based on the engine rotation speed, and even if the engine rotation speed changes in the same operating range, the knock learning value is changed in accordance with the amount of change. This ensures optimal ignition timing.

<Example> An example of the present invention will be described below based on FIGS. 2 to 4.

In FIG. 2, a control device 1 consisting of a microcomputer etc. receives a reference signal (corresponding to the engine rotation speed) and a position signal from a crank angle sensor 2 as an engine rotation speed detection means, and an intake signal from an air flow meter 3. An air flow rate detection signal, a non-king detection signal from a knocking sensor 4 as a knocking detection means, and a cooling water temperature detection signal from a water temperature sensor 5 are input.

The control device 1 operates according to the flowchart shown in FIG. 3, and outputs an ignition signal to the ignition plug 7 at a set ignition timing via an ignition device 6 consisting of an ignition coil, a power transistor, etc., to activate the ignition. ing.

Here, the setting device 1 includes an ignition timing setting means, a storage means (RAM), a retrieval means, an updating means, a retard amount setting means, a correction amount setting means, and an ignition timing correction means. Also,
The control device 1 and the ignition device 6 constitute ignition control means.

Next, the operation will be explained according to the intake air flow rate shown in FIG.

First, to explain the ignition timing, based on the engine rotation speed and the engine load such as the basic injection amount, the ignition timing ADV is searched in correspondence with the engine rotation speed and the engine load. In addition, in accordance with the knocking level detected by the knocking sensor 4, the ignition timing retard amount BETA is set to suppress knocking.
Set.

Then, the retrieved knock learning value BETL and retard amount BE
TA is simply calculated to obtain a new knock learning value BETL, and the data in the RAM is updated to this new knock learning value BETL under the same operating conditions. In addition, the period ADV
is corrected by the knock learning value BETL and the retard amount BETA to obtain the ignition timing, and based on this ignition timing, the spark plug 7
Activate the ignition.

During such knock learning control, a routine shown in the flowchart of FIG. 3 is executed.

That is, at Sl, detection signals from the crank angle sensor 2, air flow meter 3, etc. are read.

In S2, it is determined whether the current engine operating state is in the knock control range or not. If YES, the process advances to S3, and if NO, the S
Proceed to step 8. The knock control range is set to a high load higher than a predetermined value.

In S3, it is determined whether the flag is zero or not. If YES, the process proceeds to S4; if NO, the routine is ended.

In S4, the flag is set to 1. Here, flag=1 indicates that the engine operating state is in the knock control range, and flag=0 indicates that the engine operating state is in the non-knock control range. Therefore, the process proceeds to 55 the first time the knock control area is entered from the non-knock control area.

In S5, the knock learning value BETL is retrieved from the RAM based on the current driving condition under the same driving conditions.

In S6, the correction coefficient KBT is searched from the map based on the engine rotational speed detected by the crank angle sensor 2. As shown in FIG. 4, this correction coefficient KBT is
It is set to increase as the engine rotation speed increases in each operating region.

In S7, the searched knock learning value BETL is multiplied by the correction coefficient KBT to obtain a new knock learning value BETL, and the data in the RAM is updated to this new knock learning value BETL under the same operating conditions.

The knock learning value BETL updated in this manner is used in the ignition timing control immediately after entering the knock control range i from the non-knock control range.

As explained above, when entering the knock control area from the non-knock control area, the knock learning value is corrected by the correction coefficient based on the engine rotation speed, so the engine rotation speed is within the same operating area of RAM. Even if the engine rotation speed changes, the optimum ignition timing can be ensured at that engine speed, preventing non-king and output reduction.

Specifically, after performing knock learning control in the high rotation range in the same operating range of the RAM, as shown in Fig. 5, when the knock control is entered into the non-knock control range and the knock control range is re-entered in the low rotation range. Since the knock learning value secured in the high rotation range is corrected to decrease by the correction coefficient, the ignition timing is not advanced excessively and the occurrence of non-king can be prevented. Conversely, when moving from a low rotation range to a high rotation range, the knock learning value obtained in the low rotation range is increased by the correction coefficient, so the ignition timing is not excessively retarded and a decrease in output can be prevented. .

The present invention can also be applied when the engine rotational speed changes within the knock control range, and in this case, the ignition timing can be brought close to the required ignition timing with good responsiveness.

<Effects of the Invention> As explained above, the present invention calculates the ignition timing by correcting the knock learning value by the correction amount set by the engine rotation speed when the engine rotation speed changes.
Optimal ignition timing can be ensured in the entire knock control range,
It is possible to prevent the occurrence of non-king and also to prevent a decrease in output.

[Brief explanation of drawings]

Fig. 1 is a claim correspondence diagram of the present invention, Fig. 2 is a configuration diagram showing an embodiment of the book, Fig. 3 is a flowchart of the same, and Fig. 4 is a diagram showing the correspondence of claims of the present invention.
The figure is an explanatory diagram of the same operation as above, and FIG. 5 is a diagram for explaining the conventional example and the present invention in detail. 1...Control device 2...Crank angle sensor...
Knocking sensor 6...Ignition system inspection

Claims (1)

[Claims] ignition timing setting means for setting the ignition timing according to engine operating conditions; storage means for storing knock learning values for suppressing knocking in the engine operating range in correspondence with engine rotational speed and engine load; and the storage means. a search means for searching for a knock learning value under the same operating conditions as the actual engine operating state, a knock detection means for detecting knocking, and a retard amount of ignition timing in order to suppress knocking according to the detected knocking. a retard amount setting means for setting, an engine rotation speed detection means for detecting the engine rotation speed, and an engine rotation speed detection means for detecting the engine rotation speed; a correction amount setting means for setting a correction amount, and setting a new knock learning value from the set retard amount, the retrieved knock learning value, and the set correction amount, and setting the new knock learning value to the above-mentioned memory. updating means for updating the data of the means as the same operating condition; ignition timing correction means for correcting the ignition timing by the retard amount and the knock learned value; and ignition operation of the ignition plug according to the corrected ignition timing. An ignition timing control device for an internal combustion engine, comprising: ignition control means for controlling the ignition timing.