JPS6267244A - Idle engine speed control device - Google Patents

Abstract

PURPOSE:To control unpleasant shocks produced at the instant of gearing-in in an engine heating control, by stopping the fuel feeding, the ignition, and the air intake for a specific time after the shift lever is handled when the shift lever is positioned at a running range in the engine heating control. CONSTITUTION:While a shift lever 15 is handled to a running range in an engine heating control, CPU 19 sets a specific time in a timer at the instant when an inhibitor switch 16 is converted from ON to OFF. Until the timer times up, the final duty ratio of a bypass valve 10 is set at zero to close the bypass valve 10 of an idle engine speed control mechanism 8, to control the air flow to a bypass route 9 at zero. Moreover, the ignition of engine is also stopped to stop the combustion of engine reducing the engine rotation immediately. Therefore, the engine speed when the real load is imposed to the automatic transmission can be reduced, and the production of unpleasant shocks can be controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine idle speed control device.

(Prior Art) Recently, various efforts have been made to improve engine drivability and fuel efficiency in vehicle engines.

For example, when the engine is running at idle, the amount of intake air is adjusted to bring the idle speed to the target speed.
11. This aims to improve idle stability and fuel efficiency, and when the engine is cold, the amount of intake air is increased to increase the target idle speed, thereby warming up the engine and exhaust gas purification catalyst. As an example, conventionally, for example, Japanese Patent Application Laid-Open No. 1983-1
There is one shown in Japanese Patent No. 23336.

[Problem that the invention seeks to solve]

Recently, automatic transmissions with torque converters are sometimes used in vehicle engines instead of the usual manual transmissions due to their ease of operation, and they are equipped with the idle speed control device described in the above-mentioned publications. It is conceivable that the above-mentioned automatic transmission may also be installed in a vehicle engine.

However, in this case, for example, during warm-up control, the engine speed is 200 rpm or more, and during normal idle speed control, the engine speed is 11,000 rpm.
If the shift lever of the automatic transmission is operated from the N or P range to the D or R driving range in such a state and a load is applied to the engine, the problem is that it gives an unpleasant shock to the driver. be.

In view of this problem, the present invention provides an engine idle speed control device that can suppress the occurrence of an unpleasant shock at the moment of gear-in during warm-up control.

First, as a method to suppress the occurrence of an unpleasant shock at the moment of gear-in, first, when the shift lever is operated to the driving range during warm-up control, warm-up control is immediately canceled and normal idle speed control is returned to the engine. One idea is to lower the engine speed, but with this method, even if the control system returns to normal idle speed control, there is a delay in the reduction of the engine speed, and the shock cannot be suppressed sufficiently.

By the way, considering the gear shifting operations of automatic transmissions, it is common for this type of device to perform various operations using hydraulic pressure, so even if the shift lever is operated to the driving range, there is a delay in the supply of hydraulic pressure. Usually, the load actually starts acting on the engine after a predetermined period of time has elapsed.

Therefore, in an engine equipped with an automatic transmission, when the shift lever is operated to the driving range during warm-up control, there will be no adverse effect on engine drivability even if engine combustion is stopped for a period of time after the operation. Moreover, by doing this, it is possible to significantly reduce the engine speed at the moment the gear is engaged, and it is expected that this will reliably suppress unpleasant shocks at the moment the gear is engaged.

[Means for solving problems]

Therefore, as shown in the functional block diagram of FIG. 1, the present invention provides an engine idle speed control device that includes an idle speed control means 26 and adjusts the idle speed including warm-up control. , a shift lever position detection means 28 that detects when the shift lever of the automatic transmission 27 is operated from the N range or P range to the drive range; and a shift lever position detection means 28 that detects when the shift lever of the automatic transmission 27 is operated from the N range or the P range to the drive range; A correction means 29 is provided for stopping fuel supply, ignition, or intake air supply for a predetermined period after that.

[Effect]

In this invention, when the shift lever is operated from the N range or the P range to the operation range during warm-up control, the correction means 29 stops combustion of the engine for a period of time after operating the shift lever, thereby causing the engine to rotate. The number will quickly drop by the moment the gear is engaged.

(Example〕 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

2 to 6 show an engine idle speed control device according to an embodiment of the present invention. In the figure, l is an engine, and a slot 7 is located in the middle of the intake passage 2 of the engine 1.
) A throttle valve 3 is provided, and a vane type air flow meter 4 is provided upstream of the throttle valve 3. Further, a fuel injection valve 5 is installed near the downstream end of the intake passage 2, and a spark plug 7 is installed in the engine 1 facing the combustion chamber 6.

Further, an idle rotation speed control mechanism 8 is provided in the middle of the intake passage 2. In this control mechanism 8, the intake passage 2
A bypass passage 9 is branched to bypass the throttle valve 3, and a solenoid-type bypass valve 10 for adjusting the amount of air flowing into the passage 9 is disposed in the middle of the bypass passage 9.

Further, in the figure, 11 is an ignition coil, 12 is a throttle opening sensor that detects the opening degree of the throttle valve 3, 13 is a rotation speed sensor that detects the engine rotation speed, 14 is a water temperature sensor that detects the engine cooling water temperature, Reference numeral 15 indicates an automatic soft-transmission miso-silane shift lever connected to the output shaft of the engine 1 and having a torque converter. Reference numeral 116 indicates an inhibitor switch that operates when the shift lever 15 shifts from the N range or P range to the D or R travel range. , 17
is interface 18. A control unit composed of a CPU 19 and a memory 20, the memory 2
0 contains the CPU 9 arithmetic processing program (see Figure 3), the operating range determination table (see Figure 4), and various calculation maps (see Figure 5).

(see Fig. 6), etc. are stored.

The CPU 19 also controls the bypass valve 10 of the engine speed control mechanism 8 to adjust the intake air amount during idling operation of the engine, and performs feedback control of the idling speed to the target speed. Idle rotation speed control is performed by increasing the amount of intake air to perform warm-up control, and during normal operation, the ignition coil 11 is driven with an ignition advance angle according to the operating condition to ignite the engine. During idle operation, the engine performs ignition timing control that causes the engine to ignite with an idle ignition advance angle that is retarded than during normal operation.Furthermore, a fuel injection pulse is created according to the operating condition, and this is used to inject the fuel. In addition to the valve 5, fuel injection amount control is performed by injecting and supplying fuel to the engine.

Then, when the shift lever 15 of the automatic transmission is operated from the N range or the P range to the driving range during the warm-up control described above, the CPU 19 stops the ignition for a predetermined period after the operation, and also controls the idle rotation speed control mechanism. The amount of intake air flowing into the bypass passage 9 of No. 8 is controlled to be zero.

In the above configuration, the idle rotation speed control mechanism 8 and the CPU 19 serve as the idle rotation speed control means 26 shown in FIG. 1, and the CPU 19 realizes the function of the correction means 29 shown in FIG. The inhibitor switch 16 serves as a shift lever position detecting means 28 shown in FIG.

Next, the operation will be explained using FIGS. 3 to 7. Here, FIG. 3 shows a flowchart of the bypass valve 10 control and ignition timing control of the idle speed control mechanism 8 of the CPUI 9, and FIG. 4 shows the engine operating range using the engine speed and throttle opening as parameters. FIG. 5 shows the target rotation speed relative to the engine cooling water temperature, FIG. 6 shows the basic duty ratio of the bypass valve 10 relative to the engine cooling water temperature, and FIG. 7 shows the ON/OFF state of the inhibitor switch 16.
A timing chart of the OFF state, actual load timing of the automatic soft transmission, four stages of ignition, and changes in engine speed is shown. See you at the 5th FI! In J, the basic duty ratio of the bypass valve 10 is constant at a large value DB2 when the cooling water temperature is low, gradually decreases when the temperature exceeds the set temperature TWI, and becomes constant at a small value DB1 when the temperature exceeds the set temperature TWO. In addition, in Fig. 6, the target rotation speed is a constant high rotation speed N2 when the cooling water temperature is low, gradually decreases when the temperature exceeds the set temperature TWI, and decreases to a low rotation speed (usually (idle rotation speed) Nl is set to be constant.

When the encinerator is activated, the CPU 19 in the control unit 17 executes the process shown in the flowchart in FIG. ) to determine whether or not the engine is in idle operation from the engine speed and throttle valve opening.Step 31)
In the case of idling operation, use the basic duty ratio calculation map (see Figure 5) to calculate the basic duty ratio DB of the bypass valve 10 according to the engine cooling water temperature TW (Step 32), and then perform engine cooling. It is determined whether or not the water temperature TW is lower than the set temperature TWO, that is, whether the engine is in a cold state (step 33). If the engine is not in a cold state, a calculation map (see Figure 6) is used to determine whether the engine is in a cold state or not. Calculate the target rotation speed No., that is, a constant target rotation speed N1 (step 34), and check whether the current engine rotation speed N is within a predetermined range (NO+α≦N, NO−α≧N) that includes this target rotation speed No. Depending on whether or not the feedback correction value DFB of the duty ratio of the bypass valve 10 is determined by a conventionally known method.
(DFB=DFB-ΔDFB.

Step 35. Calculate DFB-DFB+ΔDFB).
36, 37, 38), this feedback correction value DFB
and the basic duty ratio DB to the final duty ratio D (
=DB+DFB) and the engine ignition advance angle 1. Step 39: Set the idle ignition advance angle to 1go.
．． 40), this final duty ratio and the ignition advance angle of 1g are outputted.Step 41.42) As a result, the bypass valve 10 of the idle speed control mechanism 8 is duty-controlled according to the final duty ratio, and the bypass passage 9 is outputted. The amount of flowing intake air is adjusted, the engine speed is feed puncture controlled to the target speed, and the engine is ignited with an ignition advance angle that is retarded than during il* operation.

Further, when the engine is operating outside the idle operating range, the CPU 19 sets the final data x kh t) to a predetermined value D.
EXT, and calculate the optimum ignition advance angle according to the operating condition based on the rotational speed and throttle opening (Step 43, 44), whereby the bypass valve 10 of the idle rotational speed control mechanism 8 is set to the above-mentioned predetermined duty ratio. DF, XT
Accordingly, the duty is controlled, and the engine is ignited with an ignition advance angle that corresponds to the operating condition. The reason why the bypass valve 10 is duty-controlled even during normal operation is to ensure control responsiveness of the bypass valve 10 when the normal operating state changes to the idle operating state.

Also, when the engine is idling, the cooling water temperature T
When the engine is cold and W is below the set temperature TWO, the CPU 19 calculates a basic duty ratio DB that is larger than that during normal idle speed control according to the engine cooling water temperature (step 32), and determines whether the inhibitor switch 16 is OFF or not. If it is ON, that is, if the shift lever 15 of the automatic transmissosilane is operated to the N range or the P range, the normal idle target rotation is set according to the engine coolant temperature TW. In step 34), the bypass valve 10 of the idle speed control mechanism 8 is duty-controlled using a larger basic duty ratio than during the normal idle speed control, and the target speed No. is higher than the target speed No. increases the amount of intake air, feedback controls the idle speed to a target speed higher than the normal target speed,
As a result, engine warm-up control is performed.

While the engine is being warmed up in this way, the shift lever of the automatic transmission
15 is operated from the N range or P range to the D range or R range (see A in Figure 7), the CP
U19 determines whether or not the moment when the inhibitor switch 16 changes from ON to OFF (step 46), and at the moment it turns OFF, sets a predetermined time A to the timer TM (step 47), and this timer TM performs a time amplification. Until then, the final duty ratio of the bypass valve 10 is set to zero, the bypass valve 10 of the idle speed control mechanism 8 is closed, the amount of air flowing into the bypass passage 9 is controlled to zero, and the ignition of the engine is stopped. (Step 4B, 49
, 50, 51), combustion in the engine is thereby stopped, and the engine speed rapidly decreases (see part 0 of FIG. 7).

When a predetermined time A has elapsed since the shift lever 15 was operated, the timer TM performs a time amplification (see B in Fig. 7).
, the CPU 19 calculates the basic duty ratio DB of the bypass valve 1o.
and set the target rotational speed NO to the basic duty ratio DB1 and target rotational speed N1 during normal idle rotational speed control (Step 48, 52.53), and set the ignition advance angle Ig to the idle ignition advance angle 1go. 4o), thereby performing normal idle speed control in which the bypass valve 1o of the idle speed control mechanism 8 is duty-controlled using the normal basic duty ratio DBI to control the idle speed to the normal target speed N1. and the engine will be fired with a predetermined idle ignition advance.

Further, the CPU 19 calculates and creates a fuel injection pulse according to the intake air amount and the engine speed, performs various corrections such as water temperature correction on this as necessary, and adds this fuel injection pulse to the fuel injection valve 5. The detailed operation is the same as that conventionally known, so a detailed explanation thereof will be omitted.

In the device of this embodiment as described above, when the shift lever is operated to the driving range during warm-up control, the ignition is stopped for a predetermined period of time to stop combustion in the engine, so that the engine speed can be quickly increased. This allows the engine speed to be lowered when the actual load is applied to the automatic soft transformer miso silane, and it is possible to reliably suppress unpleasant shocks at the moment the gear is engaged.

In addition, Figures 8 and 9 show that the shift lever 15 is pressed during warm-up control.
Another embodiment of the present invention is shown in which the fuel supply is stopped for a period after the operation when the engine is operated. In other words, in this embodiment, the fuel supply is normally determined based on the engine speed N and the intake air amount Qa. The supply amount F is calculated (step 55.56.5
7), a fuel injection pulse corresponding to this fuel supply amount F is applied to the fuel injection valve 5, and fuel of the above supply amount F is injected into the engine (step 58), while during engine warm-up control. When the shift lever 15 is operated from the N range or the P range to the travel range (see A in FIG. 9) and the inhibitor switch 16 is turned off (step 56), a predetermined time A is set in the timer TM, and this predetermined time A The fuel supply is stopped as shown in section D of FIG.
When the predetermined time A has elapsed (see B in FIG. 9), fuel supply will be started again (step 61.57.5).
8).

In the above embodiment, the ignition or fuel supply is stopped, but the present invention may also be arranged to stop the intake air supply. For example, in the first embodiment, the throttle valve is fully closed when the engine is idling. If the intake air amount is adjusted only by the bypass valve, when the shift lever is operated during warm-up control, ignition and intake air supply can be stopped for a predetermined period after the shift lever is operated.

Further, in the above embodiment, an engine speed control device equipped with a bypass type idle speed control mechanism has been described, but the present invention can be similarly applied to a device that controls the idle speed by opening and closing a throttle valve. .

Furthermore, in the above embodiment, when the shift lever is operated during warm-up control, the warm-up control is canceled and the normal idle speed control is returned to. You may do so.

〔Effect of the invention〕

As described above, according to the present invention, in the engine idle speed control device that controls the idle speed including warm-up control, the shift lever of the automatic transmission is operated to the driving range during the warm-up control. Sometimes, the fuel supply, ignition, or intake air supply is stopped for a predetermined period after the operation, which has the effect of quickly reducing the engine speed and suppressing unpleasant shocks at the moment of gear-in.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing the configuration of the present invention, FIG. 2 is an overall configuration diagram of an engine idle speed control device according to an embodiment of the present invention, and FIG. 3 is a CPU 1 in the above device.
Figure 4 shows a flowchart of the arithmetic processing in step 9, Figure 4 shows the operating range using the engine speed and throttle opening as parameters, and Figure 5 shows the basic duty ratio of the bypass valve with respect to the engine cooling water temperature. 6 is a diagram showing the target rotation speed with respect to the engine cooling water temperature, and FIG. 7 is a diagram showing the ON-OFF state of the inhibitor switch. FIG. 8 is a diagram showing a timing chart of changes in actual load timing, ignition timing, and engine speed of an automatic transmission.
FIG. 9 is a diagram showing a flowchart of the arithmetic processing of the PU 19, and a timing chart of the ON-OFF state of the inhibitor switch, the actual load timing of the automatic transmission, the change in engine speed, and the fuel injection timing. DESCRIPTION OF SYMBOLS 1... Engine, 26... Idle speed control means, 27... Automatic transmission, 28
Shift lever position detection means, 29 Correction means, 8 Idle rotation speed control mechanism, 15 Shift lever 116 of automatic transmission.
・Inhibitor Sochi, 19...CPU. Patent Applicant: Mazda Motor Corporation Agent, Patent Attorney Ken Hayase - Figure 1, Figure 8, Figure 9 Entry h

Claims (1)

[Claims] (1) In an engine connected to an automatic transmission having a torque converter on the output shaft,
An idle speed control means that adjusts the idle speed including warm-up control that increases the amount of intake air when the engine is cold, and a shift lever of the automatic transmission that is operated from the N range or the P range to the drive range. and a shift lever position detection means for detecting the shift lever position, and when the shift lever is operated to the driving range during engine warm-up control based on the output of the shift lever position detection means, fuel supply, ignition or intake is performed for a predetermined period after the operation. An engine idle speed control device comprising: a correction means for stopping air supply.