JPH0465228B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling an intake air amount control device for an engine when the engine is in an idling operating state.

Traditionally, some devices of this kind have been able to detect engine speed, throttle valve opening, etc., and perform feedback control of engine speed (idle speed control) under relatively stable conditions during idling. On the other hand, a system has been proposed in which position feedback control of the throttle valve can be performed under conditions where relatively quick control is desired during idling operation.

However, in such a conventional device, there is a problem in that a large amount of unburned gas is generated if the throttle valve opening is suddenly decreased in a state where the opening of the throttle valve is decreasing.

In contrast, when the idle switch is closed (on)
In other words, the accelerator pedal is not depressed and the throttle valve is in contact with the actuator.
If the throttle valve is under such control, it may be possible to gradually retract the actuator and gradually return the throttle valve to its minimum opening state. Even in the state of deceleration after becoming
This will activate the dart pot.

However, when decelerating from a medium load condition, unlike when decelerating after a high load condition, the dart pot is not necessary, and applying the dart pot also has the disadvantage that the engine brake is not applied properly. , fuel consumption is also bad.

Furthermore, when the throttle is suddenly closed and decelerated, the engine output (torque) changes significantly, so the shock is transmitted to the vehicle body, and this shock is particularly
This is noticeable in vehicles equipped with FF transverse engines.

In other words, the greater the temporal variation in engine output, the greater the shock. Therefore, although it is possible to reduce the temporal variation in engine output by performing doss pot control, all of the conventionally proposed means have no choice but to set a uniform touch opening degree.

In other words, since the touch opening degree during deceleration from a low load range is the same as the touch opening degree during deceleration from a high load range, the opening degree is set high even when the engine is returned to a stall.

In this conventional case, a problem arises in that the engine output increases during deceleration from a low load range.

The present invention aims to solve these problems, and by setting the opening degree of the dart pot depending on the engine load condition, it is possible to improve the fineness when the load is reduced from a high engine load condition. To provide an intake air amount control device for an engine capable of operating a fine dart pot and operating the dart pot according to the load at that time when the load is reduced from a medium load state.

Therefore, the engine intake air amount control device of the present invention sets the lower limit value of the intake air amount to the engine operating state when the acceleration control member that is manually operated to set the engine intake air amount is at the idle position. In order to set the actuator control amount according to the engine operating condition, the actuator control amount corresponding to the target opening degree of the intake air flow control valve provided in the intake passage of the engine is set, and the actuator is controlled according to the actuator control amount. control so that the control valve opening is adjusted to the target opening through the actuator, the actuator corresponding to the target idle opening when the acceleration control member is at the idle position. an idle control amount setting means for setting an idle control amount; a load sensor for detecting the engine load condition; and a non-idle control amount of the actuator when the acceleration control member is in a non-idle position. non-idle control amount setting means that repeatedly sets the amount to increase as the engine load detected by the sensor increases; When the above-mentioned non-idling control amount changes to the decreasing side, the control amount calculation is performed by comparing the value after the change with a value obtained by gradually decreasing the above-mentioned calculation control amount set in advance, and setting the larger value as the calculation control amount. and an actuator control means for controlling the actuator based on the calculated control amount when the acceleration control member occupies the idle position and then outputting the idle control amount to the actuator, the acceleration control member being in the idle position. Immediately after a rapid transition from the idle position to the idle position, the control valve opening is temporarily larger than the idle target opening, and then the control valve opening gradually decreases to the idle opening. It is characterized by

Hereinafter, an engine intake air amount control device as an embodiment of the present invention will be explained with reference to the drawings. Fig. 1 is a block diagram thereof, Fig. 2 is an overall configuration diagram thereof, and Fig. 3 is a block diagram showing its control procedure. Fig. 4 a, b, Fig. 5 a, b, Fig. 6 a~
c, Figures 7 to 10 are all graphs for explaining the action, and Figures 11 to 15 are flowcharts for explaining the action.

As shown in FIGS. 1 and 2, a throttle valve 2 is disposed in the intake passage 1 of the engine E, and a shaft 2a of the throttle valve 2 is connected to a throttle lever 3 outside the intake passage 1. There is.

Further, an end portion 3a of the throttle lever 3 has a mechanism that rotates the throttle valve 2 in the clockwise direction (opening direction) in FIG. 2 via the throttle lever 3 when an accelerator pedal (not shown) is depressed. A return spring (not shown) is connected to the throttle valve 2 to bias it in the closing direction, thereby reducing the tension of the wire. When weakened, the throttle valve 2 is designed to close.

Incidentally, an actuator 4 is provided to control the opening degree of the throttle valve 2 during engine idling operation, and this actuator 4 is equipped with a DC motor (hereinafter simply referred to as "motor") 5 having a worm 6a on its rotating shaft. The worm 6a with the motor 5 meshes with an annular worm wheel 6b.

A pipe shaft 6c having a female threaded portion 6d is integrally provided on the worm wheel 6b, and a lock 7 having a male threaded portion 7a that meshes with the female threaded portion 6d of the pipe shaft 6c is attached to the wormwheel 6b.
b and the pipe shaft 6c.

The tip of the rod 7 comes into contact with the end 3a of the throttle lever 3 via an idle switch 9 as an idle sensor when the engine E is in an idle operating state.

Here, the idle switch 9 is turned on (closed) when the engine is idling, and turned off (open) at other times.
This is a switch.

Note that the rod 7 has a long hole 7b formed therein, into which a pin (not shown) on the actuator body side is guided.
This prevents the rod 7 from rotating.

In this way, the tip of the rod 7 is connected to the engine E.
is in idle operation, the slot lever 3
Therefore, when the motor 5 is rotated in a predetermined direction, the pipe shaft 6c is rotated via the worm gear, and the rod 7 is protruded (advanced) from the actuator 4. The slot valve 2 is controlled to open, and when the motor 5 is rotated in the opposite direction to retract (retreat) the rod 7 into the actuator 4, the slot valve 2 is controlled to close by the action of the return spring. be done.

Further, a throttle opening sensor 8 is provided to detect the opening of the throttle valve 2 (throttle opening), and the throttle opening sensor 8 may be a potentiometer or the like that generates a voltage proportional to the throttle opening. is used.

Further, a water temperature sensor 11 is provided to detect hot cooling water as a warm-up temperature for the engine E, and a rotation sensor 12 is provided to detect the engine rotation speed using an ignition pulse.

Furthermore, a cooler switch 20 is provided to detect the on/off state of the cooler, and as this cooler switch 20, for example, a relay is used.

Further, a pressure sensor 21 is provided to detect intake manifold pressure (absolute value here), which is the load of the engine, and outputs a signal corresponding to the absolute value of the intake manifold pressure.

And each sensor 8, 9, 11, 12, 20,
A control unit (computer) 15 is provided, which also serves as a control means 13 which receives detection signals from 21 and outputs control signals based on these signals to the motor 5 of the actuator 4, an opening degree subtraction means 23, and a doss pot control means 24. but,
This control unit 15 performs feedback control of the engine speed based on a signal from the rotation speed sensor 12 under set conditions (described later) when the idle operating state is detected by the idle switch 9 (when the idle switch 9 is turned on). While performing idle speed control), under other set conditions (described later) when detecting the idle state, the throttle opening sensor 8
The position feedback control of the throttle valve 2 is performed based on signals from the throttle valve 2.

Here, the above conditions refer to a case where at least the following matters are satisfied, and refer to a condition in which the engine is relatively stable.

(1) A predetermined period of time has elapsed after the idle switch 9 was turned from off to on.

(2) The vehicle speed is extremely low (for example, 2.5 km/h or less).

(3) The actual engine rotational speed (actual rotational speed) NR from the target rotational speed NTW must be within the specified range.

(4) For vehicles equipped with a cooler, a predetermined period of time must have elapsed after the cooler relay, etc. was switched in accordance with the cooler load.

Further, the above conditions refer to conditions when the above conditions are not satisfied, the engine is relatively unstable, and rapid feedback control is desired.

Note that even if any of the above conditions is satisfied, if it is impossible to control the throttle opening below the minimum throttle opening or above the maximum throttle opening, the control unit 15 will not output.

Further, the position (reference position) of the rod 7 of the actuator 4 corresponding to the reference opening degree of the throttle valve 2 (this opening degree is set as a small opening degree corresponding to, for example, an engine speed of around 600 rpm). A motor position switch 10 is provided as a position sensor for detecting.
That is, this motor position switch 10 is
It is provided behind the rear end surface of the rod 7, and turns on (closed) when the rod 7 is in the most retracted state.
It is configured to be off (open) in all other cases, and this on/off signal is sent to control unit 1.
5.

Furthermore, as shown in FIG. 3, the control unit 15 receives inputs from the sensors 8 to 12, 20, and 21, and operates in a cold idle mode when the engine is in a cold state, a warm idle mode when the engine is warmed up, and a warm idle mode when the engine is warmed up. When the cooler is in use, the cooler idle up mode and dash pot mode are determined, and whether feedback control of the engine speed (idle speed control) is performed or the throttle valve 2
The control method is determined as to whether position feedback control or prospective control is to be performed, and then, according to the result of this determination, the drive time of the motor 5 (including determination of the rotational direction) is calculated, A control signal corresponding to this time can be output to the motor 5.

Here, prospective control refers to the following control. In other words, if the throttle valve 2 suddenly closes under a specified operating condition of the engine, the rod 7 is set in advance to a certain position (throttle opening corresponding to this position) in order to gradually decrease the throttle valve opening. This refers to a control in which the dart is advanced according to the expected degree until the darts pot opening is reached. It is possible to reduce it to a degree. The mode that performs this kind of control is the dart pot mode (DP mode).

The control by this control unit 15 will be explained below.

First, the processing flow for performing this control is, in principle, executed in synchronization with the ignition pulse. Note that this main flow occurs when the engine is not operating (when the engine is stalled).
When there is no ignition pulse, as in , the ignition is executed in synchronization with a pseudo pulse signal such as a clock having a predetermined period (ΔT).

Note that the above processing flow may be executed in synchronization with a timer interrupt signal (50ms timer interrupt signal) having a certain period (for example, 50ms) of another main flow.

Now, FIGS. 11 to 15 show the processing flow of the opening degree control of the throttle valve 2 including the dart pot control. Terminal a in FIG. 12 is connected to terminal a in FIG. 13, and similarly, Terminal b in Fig. 13 is the terminal b in Fig. 14, and terminal c in Fig. 14 is the terminal b in Fig. 14.
These are connected to terminal c in Figure 5, and the first
"Return" in FIG. 5 is connected to "Return" in FIG. 12.

When the ignition key is inserted (including when the engine is started), the computer 15
Processing flows A, B, C, and D are started.

Process flow A, as shown in FIGS. 11 and 12, performs initial settings, determines the dart pot conditions, and determines the state of the dart pot. Process flow B, as shown in FIGS. This process determines whether the idle switch is stable and whether the actual speed is above a predetermined value. Processing flow C is for setting the target opening PS and target rotation speed NS, as shown in Figures 11 and 14. As shown in FIGS. 11 and 15, processing flow D is for driving the motor 5 based on the target opening PS, etc.

In processing flow A, as shown in FIGS. 11 and 12, initialization is first performed in block A0, and each flag and counter DR, K1, K5 to
K10, K20, KAC, L1~L3, L5~L7, MA,
The contents of MI, T, . . . are reset and further set to initial values.

Next, in block A1, actual opening PR, actual rotation speed NR, actual vehicle speed VR, cooling water temperature TW, manifold pressure (absolute value) VM, air conditioner switch information
IAC and idle switch information ISW are loaded.

Then, in block A2, the water temperature opening degree PTW, which is the target opening degree when the cooler is off, and the water temperature rotational speed NTW, which is the target rotational speed when the cooler is off, are set.

As shown in FIGS. 4a and 4b, this set value is a discrete numerical value obtained from a map from the cooling water temperature TW, and is determined by an appropriate interpolation method during the processing flow.

In block A3, the dumppot conditions (Id,
d, d), and the seventh
As shown in the figure, the starting opening of the dart pot, which is the throttle opening, is set to each of three values, P3, P2, and P1, depending on the magnitude of the manifold pressure and its duration.

Further, in block A3, it is determined that the vehicle is in the dart pot state, and each throttle opening degree in the middle of the dart pot is set.

First, in this dart pot condition and dart pot state, the actual rotation speed NR is equal to the predetermined rotation speed ND (=
(step a1), and when NR≦ND, each flag K5, K6, K7, K8, K9, K10,
L1, L2, L3 are reset (steps a2, a4),
The dashpot condition fulfillment flag K1 is set to 0 (non-dashpot state). (Step a3) When NR>ND, proceed to step a5, and first,
Manifold pressure VM is specified pressure α1 (=660mmHg abs)
It is determined whether the (Step aa1) Then, when VM > α1 continues for a predetermined time β1 (= 1 second) or more (Steps aa2, aa3), the predictive control start flag K5 is set immediately after the dumppot d reaches a stable state. It is set to "1" (steps a6, a7), flags K8, K9, and K10 are reset (step a8), and the dashpot condition fulfillment flag K1 is set to 3 (dashpot condition d fulfilled state). (Step a9) If VM>α1 does not continue for the predetermined time β1 or more, the next shot pot state d is determined. (Step a10) Also, when VM≦α1, the counter (timer) L1 is reset (step aa4), and if the dart pot condition d is satisfied (K1 = 3) (step aa5), the dart pot is in the state d. If so, the dart pot status D flag K8 is turned on (step aa6), and the down counter (timer) T is set to the initial setting value T0 (=
0.5 seconds) is input (step aa7), leading to the next step a10.

If the dart pot condition d is not satisfied (K1≠3), the process proceeds to the next step a10.

In step a10, it is first determined whether the manifold pressure VM is greater than a predetermined pressure α2 (=450 mmHg abs). (Step aa8) Then, when VM > α2 continues for a predetermined time β2 (=0.5 seconds) or more (steps aa9, aa10), the predictive control start flag K6 is set immediately after the dumppot d reaches a stable state. It is set to "1" (steps a11, a12), flags K9 and K10 are reset (step a13), and the dashpot condition fulfillment flag K1 is set to 2 (dashpot condition d fulfilled state). (Step a14) If VM>α2 does not continue for the predetermined time β2 or more, the next shot pot state d is determined. (Step a15) Also, when VM≦α2, the counter (timer) L2 is reset (step aa11), and the dart pot condition d is satisfied (K1=2) or the dart pot condition d is satisfied (K1=3).
If it is (step aa12), it is assumed that the dart pot is in the state d, and the dart pot state d flag K9 is turned on (step aa13), and the process proceeds to the next step a15.

Further, if the dart pot conditions d and d are not satisfied (K1<2), the process proceeds to the next step a15.

In step a15, it is first determined whether the manifold pressure VM is greater than a predetermined pressure α3 (=360 mmHg abs). (Step aa13') Then, when VM>α3 continues for a predetermined time β3 (=0.3 seconds) or longer (steps a14, aa15), the flag K10 is reset (step a16), and the dart pot d is in a stable state. If the condition has just passed, the anticipation control start flag K7 is set to "1" (steps a17, a18), and the dashpot condition satisfaction flag K1 is set to 1 (dashpot condition d fulfilled state). (Step a19) If the VM does not continue for a predetermined period of time β3 or more, release the dumppot state. (Step a20) Also, when VM≦α3, the counter (timer) L3 is reset (Step aa21), and the dumppot conditions d, d, d are satisfied (K1
≧1) (step aa2), it is assumed that the dart pot status is d, and the dart pot status d flag K10 is turned on (step aa2).
aa23), leading to the next step a20.

Furthermore, if the dart pot conditions d, d, and d are not satisfied (K1<1), step a20 is executed.
leading to.

In this way, in block A3, the dart pot condition is stored in the dart pot condition fulfillment flag K1, and each of the flags K5, K6, K7, K8, K9,
K10 is set or reset.

Next, in process flow B, as shown in FIGS. 11 and 13, first, in block B1, it is determined whether the air conditioner is stable.

First, if the air conditioner switch IAC is on (step b1) and the air conditioner flag MI is off (step b2), the air conditioner immediately after turning on flag (anticipatory control start flag) KAC is turned on. (step
b3) Then, reset the stability determination counter L5 (step b4), turn on the PFB (position feedback) instruction flag K20 (step b5),
Turn on the air conditioner flag MI. (Step b6) If the air conditioner switch IAC is on and the air conditioner flag MI is on, the stability determination counter
Based on L5, it is determined whether the air conditioner has been on for a predetermined period of time γ1. (Step b7) If the air conditioner is not on for a predetermined period of time γ1, the stability determination counter
Increase the count of L5 (step b8), turn on the PFB instruction flag K20, and then turn on the air conditioner flag MI.

Furthermore, if the air conditioner remains on for longer than the predetermined time γ1, the air conditioner flag MI is turned on.

If the air conditioner switch IAC is off and the air conditioner flag MI is on (step b9), the stability determination counter L6 is reset (step b10),
Turn on PFB instruction flag K20 (step
b11), reset the air conditioner flag MI. (Step b12) If the air conditioner switch IAC is off and the air conditioner flag MI is off, the stability determination counter
Based on L6, it is determined whether the air conditioner has been in the off state for a predetermined period of time γ1. (Step b13) Then, the air conditioner remains off for a predetermined period of time γ1.
Before continuing, the stability determination counter L6 is incremented (step b14), the PFB instruction flag K20 is turned on, and the air conditioner flag MI is turned off.

Furthermore, if the air conditioner remains off for longer than the predetermined time γ1, the air conditioner flag MI is turned off.

Next, in block B2, it is determined whether the idle switch ISW is on and stable.

In other words, the idle switch ISW is on (step b13), and the idle switch flag MA
is off (step b14), the stability determination counter L7 is reset (step b15), the PFB instruction flag K20 is turned on (step b16), and the idle switch flag MA is turned on. (step
b17) If the idle switch ISW is on and the idle switch flag MA is on, the stability determination counter L7 determines whether or not the idle switch remains on for a predetermined period of time γ2. (Step b18) Then, in a state where the idle switch ISW is not on for a predetermined period of time γ2 (L7≦γ2), the stability determination counter L7 is incremented (step b19), and the PFB instruction flag K20 is turned on. Then, turn on the idle switch flag MA.

Furthermore, if the idle switch ISW remains on for longer than the predetermined time γ2, the idle switch flag MA is turned on.

If the idle switch ISW is off, the idle switch flag MA is immediately reset (step b20), and the processing of block B2 is ended.

Next, in block B3, it is determined whether the actual vehicle speed VR is greater than the predetermined vehicle speed VS (=2.5 km/hour) (step b21), and if VR>VS,
Turn on PFB instruction flag K20. (step
b22) If VR≦VS, proceed to the next block C1.

Next, in processing flow C, as shown in FIGS. 11 and 14, first, in blocks C1 and C2, the opening degree of the dart pot is determined according to the state of the dart pot, and this opening degree is set as the target scheduled opening degree.
Put it in PS1.

First, the dart pot condition fulfillment flag K1 determines whether the dart pot condition d is met immediately after (K1
= 3) (step cc1),
If it is immediately after, input the doss pot d opening degree P3 (see FIG. 7) to the target planned opening degree PS1. (Step cc2) If it is not immediately after the establishment of the dart pot condition d, the dart pot status d flag K8
It is determined that the dart pot state is d (step cc3), and if the dart pot state is d, the down counter T is subtracted by ΔT (step cc4) until the down counter T becomes 0 or less, that is, 0.5 seconds have elapsed. The dart pot d opening P3 is set as the target scheduled opening PS1 until the target opening PS1 is reached.
(Steps cc5, cc6) After 0.5 seconds, as shown in Figure 7,
The held target expected opening degree PS1 is decreased by a predetermined opening degree ΔP so that the target expected opening degree PS1 of the dart pot d is decreased in a stepwise manner. (Step cc7) Target planned opening reduced by this predetermined opening ΔP
If PS1 is larger than the dosspot d opening P2, the operation of subtracting the predetermined opening ΔP is repeated. (Steps cc7, 8) The target planned opening PS1 is the doss pot d opening P2
When the following conditions occur, the dart pot state d flag K8 is reset in order to cancel the dart pot state d (step cc10), and the dart pot state d opening degree P2 is set as the target expected opening degree PS1. (Step cc9) According to the dumppot status d flag K8,
When it is determined that the dartpot condition d is not d (K8=0) (step cc3), it is determined by the dartpot condition satisfaction flag K1 whether or not the state has just met the dartpot condition d (K1=2) (step c11); If it is immediately after, input the doss pot d opening degree P2 (see FIG. 7) to the target planned opening degree PS1. (Step cc12) If it is not immediately after the establishment of the dart pot condition d, the dart pot status d flag K8
It is determined that the needle pot is in the state d (step cc13), and if the needle pot is in the state d, the target planned opening PS1 of the dart pot d is maintained so as to decrease in a stepwise manner as shown in FIG. The target planned opening degree PS1 is decreased by a predetermined opening degree ΔP. (Step cc14) The expected opening degree decreased by this predetermined opening degree ΔP.
If PS1 is larger than the doss pot opening degree P1, the operation of subtracting the predetermined opening degree ΔP is repeated. (Steps cc14, 15) The target planned opening PS1 is the dart pot d opening P1
When the following conditions occur, the dart pot state d flag K9 is reset in order to cancel the dart pot state d (step cc17), and the dart pot state d opening degree P1 is set as the target scheduled opening degree PS1. (Step 16) According to the dumppot status d flag K9,
When it is determined that the dart pot condition is not d (K9=0) (step cc13), it is determined by the dart pot condition fulfillment flag K1 whether or not the state is immediately after the dart pot condition d is satisfied (K1=1) (step cc18); If it is immediately after, set the target opening of the dart pot d opening P1 (see Figure 7).
Input to PS1. (Step cc19) If it is not immediately after the establishment of the dartpot condition d, it is determined by the dartpot status d flag K10 that the dartpot status is d (step cc20), and if the dartpot status is d, as shown in FIG. Then, the held target expected opening degree PS1 is decreased by a predetermined opening degree ΔP so that the target expected opening degree PS1 of the dart pot d decreases in a stepwise manner. (Step cc21) Target planned opening reduced by this predetermined opening ΔP
If PS1 is larger than the doss pot opening degree P1, the operation of subtracting the predetermined opening degree ΔP is repeated. (Steps cc20, 21) According to the dumppot status d flag K10,
If it is determined that the dumppot is not in the state d (step cc20), the flow goes to block C4.

Each of the above steps cc2, cc6, cc7, cc9, cc12,
After the target scheduled opening PS1 is set at cc14, cc16, cc19, and cc21, the PFB instruction flag K20 is set (step cc22), and in block C3 it is determined that this target scheduled opening PS1 is larger than the water temperature opening PTW. Then, in block C5, it is determined whether the cooler is on and stable, and it is determined whether the air conditioner flag MI is on and the target planned opening degree PS1 is equal to or greater than the cooler opening degree PAC.

In addition, in block C3, the target planned opening PS1
If it is determined that the water temperature is less than or equal to the water temperature opening degree PTW, the process proceeds to block C4.

Block C4 uses the water temperature opening PTW as the target planned opening.
This is to be established in PS1, and after making this setting in step cc23, each flag K5, K6, K7,
Reset K8, K9, and K10 (step cc24), then proceed to block C5.

In block C5, it is determined whether the air conditioner is stable in the on state based on the on/off state of the air conditioner flag MI (step cc25), and the MI
=0, that is, if the air conditioner is off or on and unstable, the process goes to block C6.

If MI=1, when the target planned opening PS1 is greater than or equal to the cooler opening PAC (step cc26), the flag KAC is reset immediately after the air conditioner is turned on (step
cc27), which leads to block C6.

Further, when MI=1 and the target expected opening degree PS1 is smaller than the cooler opening degree PAC, the process proceeds to block C7.

Block C6 uses the target planned opening PS1 as the target opening.
Set to PS (step cc28), water temperature rotation speed NTW
Set the target rotation speed NS. (Step cc29) Then, in block C7, the cooler opening degree PAC is set to the target opening degree PS (step cc30), and the cooler rotational speed NAC is determined to be the target rotational speed NS. (Step cc31) When the flow in blocks C6 and C7 is completed, the flow advances to the next block D1.

Next, in process flow D, as shown in FIGS. 11 and 15, first, in block D1, whether or not the idle switch ISW is on and stable is determined based on the idle switch flag MA.

Then, if the idle switch ISW is on and stable, in block D2, the rod 7 is controlled according to position feedback control or rotation speed feedback control.
to drive.

That is, immediately after the air conditioner is turned on, the flag KAC is reset (step d1), and the actual opening PR is set to the intermediate opening.
Set to PM (swipe step d2) and calculate the difference ΔN (= NS - NR) between the target rotation speed NS and the actual rotation speed NR. (Step d3) When the absolute value |ΔN| of this difference ΔN is greater than or equal to the predetermined value δ (step d4), PFB is selected and the process proceeds to step d5.

Note that even if this absolute value |ΔN| is smaller than the predetermined value δ, if the PFB instruction flag K20 is on (K20=1) (step d6'), the step
Reach d5.

In step d5, this series of processing flow A,
A reset is performed to reset the PFB instruction flag K20 for each of B, C, and D.

Then, the difference ΔP (=
PS-PR) (step d6), and the driving time ΔD of the motor 5 is calculated from the difference ΔP.
(Step d7) Furthermore, when the absolute value |ΔN| is smaller than the predetermined value δ, the PFB instruction flag K20 is turned off (K20=
0) (step d6'), the driving time ΔD of the motor 5 is calculated from the difference ΔN in step d9. (Step d9) That is, the driving time ΔD of the motor 5 is calculated from ΔP or ΔN, respectively.

Here, examples of the ΔP-ΔD characteristics and the ΔN-ΔD characteristics are shown in FIGS. 5a and 5b.

Furthermore, it is determined whether or not each ΔD can be set. (Steps d8, d10) Here, in the case of position feedback control (step d8), for example, if 100 ms has elapsed, it is possible (YES), otherwise it is impossible (NO).
In the case of engine speed feedback control (step d10), it is possible if a longer period of time has elapsed than in the above case, for example 700 ms.
Otherwise, it will be judged as impossible.

In other words, in position feedback control,
Control is possible every 100ms, and engine rotation speed feedback control allows control every 700ms.

Thereafter, in step d11, .DELTA.D is set in a motor drive timer, and in step d12, the motor 5 is driven until the timer reaches 0.

Note that when ΔD is positive, the throttle valve 2 is driven to the open side, and when ΔD is negative, the throttle valve 2 is driven to the open side.
The throttle valve 2 is driven to the closing side.

As a result, the engine can be controlled in a targeted state in both engine speed feedback control and position feedback control. In other words, the engine idle speed can be controlled to an optimal state.

In addition, in either step d8 or d10,
If the determination is NO, the motor drive control is not performed and the process returns.

The above processing flow, steps d4 to d8, d11,
d12 is hereinafter referred to as "PFB control processing flow F1."

By the way, if the idle switch ISW is on and unstable (MA=0), the block
At D3, it is determined whether the dart pot is in its initial state or just after the cooler is turned on.

First, in step d13, the PFB instruction flag
K20 will be reset.

Then, it is determined whether the prospective control start flag K5 is on (step d14), and if it is on,
Flag K5 is reset (step d15) and the process proceeds to step d16.

If the prospective control start flag K5 is off, it is determined whether the prospective control start flag K6 is on (step d17), and if it is on, the flag K6 is reset (step d18), and the process proceeds to step d16.

If the anticipatory control start flag K6 is off, the flag immediately after the air conditioner is turned on (anticipatory control start flag)
Determine if KAC is on (step
d19), if it is on, resets the flag KAC (step d20) and proceeds to step d16.

If the flag KAC is off immediately after the air conditioner is turned on,
Determine whether the prospective control start flag K7 is on (step d21), and if it is on (K7=1),
Flag K7 is reset (step d22) and the process proceeds to step d16. If the flag K7 is off (K≠1), the process goes to block D5.

As mentioned above, the dart pot condition (d,
When d, d) becomes stable or immediately after the air conditioner is turned on, turn off the idle switch.
ISW is off (or on and not stable)
If so, the process proceeds to step d16.

In step d16, for prospective control, the difference ΔP (=PS - PM) between the target opening PS and the intermediate opening PM (for example, the actual opening PR is input) is calculated.
Determine whether this difference ΔP is positive (step
d22′), if ΔP>0, it will lead to block D4,
If ΔP≦0, the process goes to block D5.

In block D4, since the rod 7 does not protrude to the dash pot openings P1, P2, P3 or the cooler opening PAC, the rods 7 are moved to each of these openings.
Expected control is performed so that P1, P2, P3, and PAC are projected.

First, the target opening degree PS is set to the intermediate opening degree PM (step d23), and the drive time ΔD of the rod 7 is set in accordance with ΔP. (Step d24) Then, in steps d25, d26, and d27, the rod 7 is driven by anticipation control as in steps d8, d11, and d12, and then the process returns.

If it is not possible to set ΔD, this drive time ΔD is accumulated in the memory DR (step d28), and then the process returns.

Note that the processing flow, steps d22 to d27, will be referred to as "expected control processing flow F2" hereinafter.

In block D5, the drive time DR accumulated in the memory DR is stored without passing through the prospective control processing flow F2.
The rod 7 is driven accordingly.

That is, if it is possible to set ΔD (step d29), step d30, until DR becomes zero,
At d31 and d33, rod 7 is driven and further resets DR. (Step d32) If it is impossible to set ΔD, the process returns, and also returns if DR=0.

In addition, in the above-mentioned processing flow, a block etc. according to the water temperature TW may be added. in this case,
Cold idle mode switching slot opening Pmax
is set.

Since the engine intake air amount control device of the present invention is configured as described above, when the engine cooling water temperature TW is low, that is, when the engine is in a cold state (PTW>Pmax), [symbol G1 in Fig. 4a]
Reference], the water temperature opening degree PTW is set. This mode is a cold idle mode.

In addition, when the engine is warmed up (PTW≦Pmax), each processing flow A, B, C, D
A comparison is made between the cooler opening degree PAC and the water temperature opening degree PTW according to the on/off state of the cooler.
Each control is performed based on this.
[See symbols G2 and G3 in Fig. 4a] () When the throttle valve 2 is suddenly closed (see Fig. 8) In this case, the throttle valve 2 is suddenly closed and the idle switch ISW is immediately turned on. , the manifold pressure VM drops rapidly, so that dumppots d, d, d occur in succession. (Refer to symbols Q2 and Q4 in Fig. 7) First, when the dart mode d is established,
According to the prospective control processing flow F2, prospective control is performed on the opening degree P1 of the doss pot d.

Next, according to the prospective control processing flow F2,
Similarly, anticipatory control is performed on the doss pot d opening degree P2 and the doss pot d opening degree P3.

Then, from the time when the idle switch ISW (9) is turned on and the throttle valve 2 comes under the control of the actuator 4, control based on the dart pot status is also performed from the dart pot opening degree P3. This process is the PFB control processing flow
Conducted by F1.

Similarly, since the idle switch ISW continues to be on, the needle pot d opening
P2 and the opening degree P1 of the dart pot d are also controlled depending on the state of the dart pot. This process is the PFB control processing flow
Conducted by F1.

() When throttle valve 2 is gradually closed (9th
(See figure) In this case, the throttle valve 2 is gradually rotated to the closing side, and it takes time for the idle switch ISW to turn on, and the manifold pressure increases.
Dashpots d, d, d are rarely performed since the VM decreases slowly. The target planned opening PS1 at this time is the symbol in Fig. 7.
Shown in Q1, Q3, and Q5.

However, in the same way as when the throttle valve 2 is suddenly closed, due to the prospective control processing flow F2,
Dashpot d opening degree P1, Dashpot d opening degree P2, and Dashpot d opening degree P3
Expected control is performed for each.

Then, from when the idle switch ISW is turned on and the throttle valve 2 comes under the control of the actuator 4, control based on the dart pot state is performed from the dart pot opening degree P1. This process is performed by the PFB control process flow F1.

As shown in Figures 6a-c, the manifold pressure
After a predetermined time has elapsed (see code T2 in the figure) after VM exceeds a predetermined manifold pressure (for example, α1) (see code T1 in the figure), the machine enters the dart pot mode (DP mode).

Then, when the manifold pressure VM falls below the above-mentioned predetermined pressure (see symbol T3 in the same figure)
After a predetermined time TP (0.5 seconds in this case) has elapsed (see reference numeral T4 in the figure), the device enters the dumppot state.

That is, subtraction of the target opening degree PS starts from time T4.

From the time the idle switch ISW is turned on (see code T5 in the same figure), this target opening
The rod 7 is driven by the PS by the motor 5. The drive of this motor 5 is based on the target opening degree.
This is continued until PS reaches a predetermined opening degree (see reference numeral T6 in the figure).

() In the case of any operating state (see Fig. 10) Here, an example of control according to the on/off of the cooler switch IAC (20) and the on/off of the idle switch ISW is shown. That is, an example in which the dumppot state continuously occurs is shown.

As in the above case, the expected control processing flow
With F2, prospective control is performed on the dart pot d opening P1, the dart pot d opening P2, the cooler opening PAC, and the dart pot d opening P3. (Signs Q1, Q3 in Figure 7,
(Refer to Q5) Regarding the dart pot control when the idle switch ISW is on, the operation is almost the same as when the throttle valve 2 is suddenly closed and when the throttle valve 2 is gradually closed.

In each of these states, the cooler opening PAC or target planned opening PS1 when the cooler is on is
The protrusion control of the rod 7 is performed at a larger opening. Note that an intake air amount/engine rotation speed (A/N) detector may be used as the load sensor, and the throttle opening sensor 8 may also serve as a load sensor without providing a load sensor. may be configured.

Also, without setting the time setting values β1, β2, and β3,
It is also possible to simply compare the manifold pressure VM and the predetermined pressures α1, α2, α3.

Further, the present device can be applied to both engines having a carburetor type fuel supply system and engines having an injector type fuel supply system.

As described in detail above, according to the engine intake air amount control device of the present invention, the following effects and advantages can be obtained.

(1) When the engine load is reduced from a high load state, the dart pot can be operated, and when the load is reduced from a medium load state, the dart pot can be operated according to the load at that time.

(2) When decelerating from a medium load state, engine braking is better applied, contributing to improved safety and improving fuel efficiency.

(3) The throttle opening when decelerating from a low load range and the throttle opening when decelerating from a high load range can be set to different throttle openings.

(4) When the throttle is suddenly closed and decelerated, the amount of change in engine output (torque) is reduced, and as a result, the impact transmitted to the vehicle body is extremely small. In particular, even in a vehicle equipped with a FF transverse engine, this impact force can be made extremely small.

(5) Engine output does not increase even during deceleration from a low load range.

(6) The temporal variation in engine output can be kept small without impairing the effectiveness of engine braking.

[Brief explanation of the drawing]

The figures show an engine intake air amount control device as an embodiment of the present invention. Fig. 1 is a block diagram thereof, Fig. 2 is an overall configuration diagram thereof, and Fig. 3 is a block diagram showing its control procedure. , Figure 4 a, b, 5th
Figures a and b, Figures 6 a to c, and Figures 7 to 10 are graphs for explaining the effects, and Figures 11 to 1.
5 are flowcharts for explaining the operation. 1... Engine intake passage, 2... Throttle valve, 2a... Shaft, 3... Throttle lever, 3a
... Throttle lever end, 4 ... Actuator, 5 ... Motor, 6a ... Worm, 6b ...
Worm wheel, 6c...pipe shaft, 6d...
Female thread part, 7... Rod, 7a... Male thread part, 7
b...Elongated hole, 8...Throttle opening sensor, 9...
...Idle switch (idle sensor), 10...
... motor position switch (position sensor), 11 ... water temperature sensor, 12 ... rotation speed sensor, 13 ... control means, 15 ... control unit (computer ), 20...
Cooler switch, 21... Manifold pressure sensor as a load sensor, 22... Opening degree setting means, 2
3... Opening degree subtraction means, 24... Dashpot control means, E... Engine.

Claims (1)

[Claims] 1. A device provided in the intake passage of the engine in order to set the lower limit value of the intake air amount according to the operating state of the engine when the acceleration control member, which is manually operated to set the intake air amount of the engine, occupies the idle position. The actuator control amount corresponding to the target opening of the intake flow rate control valve is set according to the engine operating state, and the actuator is controlled by the actuator control amount, and the control valve opening is adjusted to the above through the actuator. An idle control amount setting means for setting an idle control amount of the actuator corresponding to the idle target opening when the acceleration control member is at the idle position; a load sensor that detects a load state of the actuator, and a non-idle control amount of the actuator when the acceleration control member is in a non-idle position, so that the control amount of the actuator increases as the engine load detected by the load sensor increases. a non-idle control amount setting means to set, and when the non-idle control amount changes to the increasing side, the value after the change is set as the calculated control amount, and when the non-idle control amount changes to the decreasing side, the value after the change is set; control amount calculation means for comparing the value of the calculation control amount with a value obtained by gradually decreasing the calculation control amount set in advance and setting the larger value as the calculation control amount; The control valve includes actuator control means for controlling the actuator based on the calculated control amount and then outputting the idle control amount to the actuator, and the control valve immediately after the acceleration control member rapidly shifts from the non-idle position to the idle position. An intake air amount control device for an engine, characterized in that the opening degree is temporarily larger than the target idle opening degree, and then the control valve opening degree gradually decreases to the idle opening degree.