JPS60122273A - Idling speed control device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To enable variation in torque and increase the response of idling speed control by correcting the ignition timing in accordance with a compared result between actual idling speed and target idling speed. CONSTITUTION:When judgment is made to be in an idling condition, from the output of an idle switch, a neutral switch, a car speed sensor, etc., which are turned on as a throttle valve is totally closed, an ignition timing correcting routine is executed by a control circuit. That is, a target idling speed Ns, which is predetermined in accordance with a cooling water temperature, is retrieved from the detected value of the cooling water temperature. Also, an actual idling speed N is detected from the output of an idling speed detecting means such as a crank angle sensor, etc. Then, deviation DELTAN between both idling speeds Ns, N is obtained by a comparing means, and the correcting value of ignition timing, which is predetermined in accordance with the deviation DELTAN, is retrieved from the deviation DELTAN. After that, this corrected value is added to the ignition angle of lead, to control an ignition device as a new ignition angle of lead.

Description

[Detailed description of the invention] Technical fields> The present invention relates to an idle speed control device for an internal combustion engine.

<Prior art> In conventional internal combustion engines, the idle speed is controlled by, for example, as shown in FIG. 1, an idle control valve 3 is provided in a bypass passage 2 that bypasses a throttle valve 1, and the opening degree of this idle control valve 3 is By controlling the engine speed, the idle speed was fever-controlled. In FIG. 1, 4 is a knee j' cleaner, 5 is an air flow meter, 6 is an engine body, and 7 is a control unit.

This feedback loop consists of: ■ Idle rotation speed detection ■ Comparison with target idle rotation speed (deviation calculation) ■ Control output to the idle control valve according to the deviation ■ Idle control valve operation ■ Change in intake air amount ■ Explosive force change ([・Change in torque) - This is a change due to eye rotation.

Here, if ■～■ is detected instantly? i15. Although the delay in operation for (2) is negligible, the processes (2) and (2) take a considerable amount of time.

For this reason, there are problems in that the integration time of the feed hack is delayed and even minute fluctuations in idle rotation cannot be absorbed (feedback).

<Object of the Invention> In view of these conventional problems, the present invention provides a method for improving the responsiveness of idle rotation speed control and significantly improving control speed, either in combination with conventional air flow control or alone. The purpose of the present invention is to provide an idle speed control device that can perform the following tasks.

<Structure of the Invention> Therefore, the present invention achieves 1 by advancing or retarding the ignition timing.
- Focusing on the fact that the torque can be changed, as shown in Fig. 2, a comparison is made in which the idle speed detection means that detects the actual idle speed is compared with the actual idle speed and the target idle speed. and an ignition timing correction means for correcting the ignition timing of the ignition device by 7111 in accordance with the comparison result, thereby constructing an idling speed control device.

Examples> Examples will be described below. In this example, the same unit performs fuel injection amount control, ignition timing control, and idle speed control (air amount control). The rotation speed is controlled.

First, the hardware configuration will be explained with reference to FIG.

8 is CPU, 9 is P-1? OM, 10 is an A/I) converter, and 11 is an address decoder.

The analog signals ζ are the intake air flow base signal from the air flow meter 5, the water temperature signal from the water temperature sensor 12, the oxygen concentration in the exhaust from the 02 sensor 13, and the voltage from January 4, 2015, etc. , these are input to the A/D converter 10 via the analog input interface 15 and then input to the CPU 8.

As a digital input signal, eye]・'Rusuinochi16
, the neutral switch 17, the air conditioner switch 18, etc., and these are input to the CI) U 8 via the decile input interface 19.

In addition, a reference signal every 180 degrees and a position signal every 1 degree from the crank angle sensor 20 are manually input to the CPU 8 via the waveform shaping circuit 2I, and a vehicle speed signal from the vehicle speed sensor 22 is input to the waveform shaping circuit 23. via CPU
8 is input.

From the CPtJ8, the current is sent to the fuel injection valve 25 via the current control circuit 24, to the ignition coil (i:l< is a power transistor for its operation) 27 via the ignition coil driver 26, and via the phase inversion driver 28. output signals are sent to the valve opening coil 3a and valve closing coil 3b of the idle control valve 3, respectively. The idle control valve 3 is a rotary set, and a pulse signal is sent to the development phase coil 3a and the valve-closing coil 3b in a mutually inverted state, and the opening degree is adjusted according to the duty ratio of the pulse signal. Ru.

The fuel injection amount is controlled by measuring the period of the intake air flow 11fiQ detected by the air flow meter 5 and the reference signal from the crank angle sensor 2().
The basic injection amount T p (- to -
Q/N is a constant), and the air-fuel ratio feedback correction coefficient α is calculated based on the signal from the 02 sensor 13, and the voltage correction valve 1゛S is based on the voltage of the battery 14.
etc., the injection amount 'I''1(-Tp・α+Ts
) and outputs a drive pulse of pulse rlj corresponding to this injection amount Ti to the fuel injection valve 25 via the current control circuit 24 at a predetermined timing.

The ignition timing is controlled by searching for a predetermined ignition advance angle ADV from the engine speed N and the basic injection amount Tp, and based on this search value.
is determined, and if the reference signal from the crank angle sensor 20 is output at 80 degrees before compression top dead center, enter (80 degrees - ΔD■) in the counter and input the reference signal or manually input 1 , the count value is subtracted by one each time the position signal jib from the crank angle sensor 20 is input. (When the count value reaches 0, the power transistor of the ignition coil is An ignition signal is output to 27.

At the time of I-1, follow the flowchart l- in Figure 4 (
The idle speed is controlled by correcting the ignition timing. In addition, the vehicle speed is determined by the neutral switch 17, which is turned on when the throttle valve is in the fully closed position, and the neutral switch 17, which is turned on when the transmission gear position is neutral. Based on the signal from the sensor 22, the idle switch 16
is on and the neutral switch 17 is on, and when the idle switch I6 is on, the vehicle speed sensor 22
When the vehicle speed detected by C is less than a predetermined value,
The ignition timing shown in Figure 4 is determined to be 0°ζ. ili positive routine.

To explain the ignition timing correction routine, from the water temperature '1゛W detected by the water temperature sensor 12 at Sl, the target idle rotation speed NS is determined in advance.
;? i-Search and if necessary near Consiso-F-18
Did you respond to the on/off etc.? lli correction is applied to set the target 1° idle rotation speed NS. Then, in S2, the actual wheel rotation speed N is detected by calculating the period of the reference signal from the crank angle sensor 20. Incidentally, in detecting the actual idle rotation speed N, a plurality of data of the latest detected values may be stored in memory 117if, and the average value thereof may be calculated and used as the actual idle rotation speed N. In this case, a weighted average may be taken.

Then, in S3, the deviation ΔN (=N-Ns) of the actual idle rotation speed N with respect to the target idle rotation speed Ns is calculated. Then, in S4, a predetermined correction value for the ignition advance angle; 1dV is searched from the deviation ΔN. stop? c.3
In step 5, the correction value adv is added to the ignition advance angle A1)V to newly set the ignition advance angle A1)V, and this is set in the above-mentioned counter.

Here, the ignition timing that generally occurs at idle is the optimum ignition timing MBT (for example, top dead center 1iij 40 to 5
Since it is not at 0゛) but on the retard side (for example, 30 degrees before the ignition point) than M B T, it is necessary to advance the ignition timing by rdi.
If it stops, the torque increases, and conversely, the correction deviation LJ torque decreases when the angle is retarded 11111.

Therefore, the larger the deviation ΔN is on the →- side (actual eye)
- The larger the idle rotation speed N is than the target idle rotation speed pJs), the larger the correction value adv is, for example, the ignition advance angle AD
V is made small, that is, the ignition timing is delayed and the torque is reduced, thereby lowering the idle speed and approaching the target idle speed pJs.

For example, the larger the deviation ΔN is (the smaller the actual idle speed N is than the target idle speed Ns), the larger the correction value adv is on the + side, the larger the ignition advance angle ADV, and the smaller the ignition timing. The engine speed is increased to increase the torque, thereby lowering the idle speed to bring it closer to the target idle speed.

If the engine speed is controlled by such ignition control, the explosion caused by the ignition will have a positive effect, so
Control speed has been significantly improved and even minute rotational fluctuations can be absorbed.

In addition, the control of the idle rotation speed by the air amount control is performed by the fifth
According to the flowchart 1 in the figure, the control value l5Cdy of the duty ratio of the pulse signal to the eye 1-lumi 1i control valve 3 is
This is done by outputting q and adjusting the opening degree of the control valve 3 based on the respective control value l5Cdy.The unit of this control value is expressed in whites, and lTh'J J?
It is output as the percentage of time that the utility coil 3a is on.

To explain the air amount control routine, the basic control value I S CLw of the duty ratio of the pulse signal to the idle control a11 valve 3, which is determined in advance, is searched based on the water temperature detected by the water temperature sensor 2 in Sll. . Then, in step 312, various Ni positive 1i1scetfc settings such as air and :1 correction are performed as necessary. And Sl
3, compare the actual idle rotation speed N and the target idle rotation speed Ns, and perform a foot hack correction of 11s using proportional-integral control.
Set cfb. That is, N > N! In the case of +,
In S14, +5erb is decreased by a predetermined amount from the previous value based on proportional-integral control, and if N<NS, 15Clb is increased by a predetermined amount from the previous value based on proportional-integral control in S15. In the case of N-N5 (including dead zone), l
Leave 5Cfb at its previous value. Then, in 316, the control value 1 of the duty ratio of the pulse signal of the idle control valve 3 is
Calculate scdy by the following formula (9) and output.

I 5Cdy= I SCtw4- I 5Cet-1
-I 5Cfb If the control value 1sCdy is calculated, a pulse signal with a tute ratio corresponding to this control value + 5cdy is transmitted via the phase inversion 1-rhyme 28 to open the valve of the control mechanism 3 = toil 3a and close the valve. coil 3b. As a result, the opening degree of the idle control valve 3 is adjusted.
Air volume is controlled.

When used in conjunction with this 1. air amount control, 1. Rui? By controlling the wheel rotation speed,
, ~)'a) - It is possible to absorb even minute fluctuations in a stable state.

However, it is not necessary to use the air control and 01, and it is also possible to use the ignition 1 & etc. 11. ,+7 different ゛J'Kunayu J--ta ze・
It has the advantage of not being necessary.

(The result of the invention) Thus, according to the present invention, the ratio of the number of actual air times to the number of actual air times and the number of real air times is 1. Change the torque by correcting the ignition timing according to the result1
The idle speed is controlled by
The explosion caused by the ignition can be effectively controlled, the li control speed is significantly improved, and as a result, even the slightest change in J can be absorbed.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a conventional idle speed control device, Fig. 2 is a program diagram showing the configuration of the present invention, and Fig. 3 is a diagram showing an embodiment of the present invention. FIG. 4 is a flow chart 1-1 of idle speed control using ignition timing correction, and FIG. 5 is a flow chart 1- of idle speed control using air amount control. 3...I/L control valve 8...CP tJ 12
...Water temperature sensor 20...Crank angle sensor 26
...Ignition coil driver 27...Ignition coil patent applicant Fujio Sasashima, agent of Japan Electronics Co., Ltd., patent attorney

Claims (2)

[Claims] (1) Idle rotation speed detection means for detecting the actual idle rotation speed, comparison means for comparing the actual idle rotation speed with the target idle rotation speed, and correcting the ignition timing by the ignition device according to the comparison result. An idling speed control device for an internal combustion engine, comprising ignition timing correction means. (2) Claim 1, wherein the aisle rotation speed detection means calculates the average value of the latest detected values of the plurality of aisle rotation speeds and determines the actual idle rotation speed. 3'FA, engine idle speed control device