JPH1150879A - Throttle valve control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the reduction of a number of the revolutions of an engine in vehicle deceleration resulting from an error influenced by the temperature characteristics of a throttle sensor without significantly influencing on a vehicle behavior by raising reference position learning value during a vehicle running. SOLUTION: During a vehicle running, ISC required opening by an ISC(idle speed control) control is computed in an ECU 17. The ISC required opening is computed as an addition value of an ISC feedback control amount, an air conditioner estimated amount, a water temperature correction amount, and the like. Based on the operation state and the control state of the vehicle, required opening except the ISC required opening is computed. A final target opening against a throttle valve 10 is computed from, for example, nonlinear required opening based on actual accelerator opening equivalent to a driver's accelerator operation, the computed ISC required opening, and the other respective required openings. A reference position being the reference of throttle control is added to a required voltage corresponding to the final target opening so as to compute a control voltage for driving a DC motor 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a throttle valve control device for an internal combustion engine having an electronically controlled throttle valve. In particular, the present invention performs learning to calculate the control reference position from the output value of the throttle sensor when the throttle valve is at the reference position when the ignition is turned on and to store the control reference position as a reference position learning value. The present invention relates to a throttle valve control device for an internal combustion engine that controls a valve.

[0002]

2. Description of the Related Art Conventionally, it has been known that a throttle valve of an internal combustion engine is electronically controlled by an actuator including a DC motor and an electromagnetic clutch. In the electronically controlled throttle valve control system, the control reference position is learned when the ignition is turned on (IG-ON). That is, the control reference position (control origin) of the throttle valve is calculated from the output of the throttle sensor when the throttle valve is at the reference position at the time of IG-ON, and is stored as a reference position learning value. Then, the throttle valve is controlled based on the stored reference position learning value.

Further, when learning before starting the engine is not executed for some reason and the throttle valve is controlled as it is,
It is also known to adopt a reference position learning value (previous value) at the time of previous learning execution as a reference position learning value of the current throttle control (for example, Japanese Patent Application Laid-Open No. 7-269406).

[0004]

However, the reference position learned at the time of IG-ON due to the influence of the temperature characteristics of the throttle sensor and the deviation of the mechanical reference position of the throttle valve (opener, fully closed stopper, fully opened stopper) and the like. An error may occur in the learning value. For example, when the temperature of the throttle sensor decreases due to traveling wind caused by traveling of the vehicle,
The reference position learned at the time of IG-ON may shift during driving. In such a case, the engine speed may drop during deceleration during traveling, causing engine stall.

[0005] In addition, when the vehicle travels while adopting the reference position learning value at the time of previous learning as the reference position learning value at the time of IG-ON, a similar problem occurs due to an error in the reference position learning value due to the temperature characteristics of the throttle sensor. Occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has the following objects. (1) Raising the reference position learning value during running of a vehicle has a large effect on vehicle behavior. It is possible to prevent a decrease in the engine speed at the time of vehicle deceleration caused by an error due to the influence of the temperature characteristics of the throttle sensor and the like. It is another object of the present invention to provide a throttle valve control device for an internal combustion engine capable of preventing displacement and further preventing (3) an unnecessary increase in engine speed when an accelerator pedal is depressed beyond a predetermined opening.

[0007]

A throttle valve control device for an internal combustion engine according to the present invention is a throttle valve control device for an internal combustion engine having an electronically controlled throttle valve, wherein the throttle valve is set to a reference position when the ignition is turned on. Learning means for calculating a control reference position from the output value of the throttle sensor when the control value is in the range and storing the control reference position as a reference position learning value, and control means for controlling the throttle valve based on the reference position learning value. And further comprising: a determination unit for determining whether or not the vehicle is running, and a correction unit for setting a value obtained by raising the reference position learning value to a reference position learning value when it is determined that the vehicle is running, Thereby, the above object (1) is achieved.

Further, the control means performs feedback control of the throttle valve opening so that the engine speed during idling becomes the target speed, and the correction means attenuates the raising amount during the feedback control. Thereby, the above object (2) is achieved.

Further, the correcting means sets the raising amount to zero when the accelerator opening becomes equal to or more than a predetermined value, whereby the object (3) is achieved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows a configuration of a throttle valve control device 100 for an internal combustion engine according to the present invention. FIG.
As shown in the figure, in the throttle valve control device 100, the throttle valve 10 is a computer (ECU) 17
Accordingly, the DC motor 11 and the clutch 12 that transmits the driving force of the DC motor 11 to the throttle valve 10 are controlled and driven. The ECU 17 includes, in addition to an accelerator opening sensor that detects the amount of depression of an accelerator pedal (actual accelerator opening AP), various sensors (a rotation speed sensor Ne, a water temperature sensor T).
Hw and an output value from an air amount sensor).

The actual throttle opening (actual throttle opening) TA is detected by a throttle sensor 13.
It is fed back to the ECU 17 as a throttle sensor signal. The ECU 17 performs feedback control of the DC motor 11 so that the actual throttle opening TA becomes the final target opening TANGL. The clutch 12 is in a non-coupled state (OF
In the F state, the throttle valve 10 is urged by the spring 15 so as to abut on the opener 14 (opener position). The throttle fully closed position when the throttle valve 10 is controlled to be closed is defined by the throttle fully closed stopper 16 (throttle fully closed position).

First, the throttle control will be described.
FIG. 2 is a flowchart showing the throttle control in the present embodiment.

As shown in FIG. 2, first, in step S10
In ISC (Idle Speed Control) control
The C required opening is calculated. Here, the ISC required opening is I
It is calculated as an added value of the SC learning amount, the ISC feedback control amount, the expected shift amount, the estimated air conditioner amount, the water temperature correction amount, the estimated electric load amount, and other estimated amounts.

In step S11, a required opening other than the ISC required opening is calculated based on the driving state and control state of the vehicle. For example, a nonlinear required opening based on the actual accelerator opening AP corresponding to the driver's accelerator operation, a TRC required opening based on traction control, a cruise required opening based on cruise control, a VSC required opening based on vehicle behavior control, a shift Shift required opening at the time.

In step S12, a final target opening TANGL for the throttle valve 10 is calculated from the ISC required opening calculated in steps S10 and S11 and other required opening. For example, during normal driving, the sum of the ISC required opening and each required opening is the sum of ISC and ISC.
At the time of SC control, the required ISC opening becomes the final target opening TANGL as it is.

In step S13, the final target opening degree TAN
GL is converted into a corresponding required voltage TAP. Usually, the required voltage TAP is obtained by multiplying the final target opening degree TANGL by a predetermined conversion coefficient.

In step S14, the required voltage TAP
The control voltage TT for driving the DC motor 11 is obtained by adding a reference position serving as a reference for throttle control to the control signal TT.
Calculate P. Then, by controlling the DC motor 11, the throttle valve 10 is driven so as to have the final target opening degree TANGL.

As described above, since the throttle valve 10 is controlled with reference to the reference position in step S14, learning of the reference position is usually performed before the engine is started.

In the following, before starting the engine (IG-O) in the throttle valve control apparatus 100 for an internal combustion engine according to the present embodiment,
The learning of the reference position at (N) will be described.

FIG. 3 is a flowchart showing a reference position learning routine in the throttle valve control device 100 of the present embodiment. As shown in FIG. 3, first, in step S20, the ignition switch (IG)
N / OFF is determined. If IG-ON, step S
At 21, it is determined whether the reference position learning has been completed. This determination is made, for example, by a learning completion flag (described later).
ON / OFF. If the learning completion flag is ON in the determination of step S21 and the reference position learning has been completed, this routine ends.

If it is determined in step S21 that the learning completion flag is not ON, the flow advances to step S22 to increment the learning counter. Then, to determine the value of learning counter in step S23, the value of learning counter is the case of the above T _1, a predetermined time (T ₁₎ learning elapsed despite the reference position is not performed, the learning is not satisfied The reference position learning value (previous value) at the time of the previous learning execution is adopted (step S30), and this routine ends.

If the value of the learning counter is equal to or less than T ₁ in step S23, it is determined in next step S24 whether the value of the learning counter is equal to or greater than T ₀ (where T ₀ <T ₁ ). Further, in step S25, it is determined from the output of the accelerator opening sensor whether the accelerator is depressed (accelerator opening AP <predetermined value), and in step S26, it is determined whether the throttle sensor 13 is normal. If all the determinations in steps S24 to S26 are affirmative, the current output (throttle opening TA) of the throttle sensor 13 is set as a reference position (step S27). That is, the control reference position is calculated from the output value of the throttle sensor 13 at the position of the throttle valve 10 (in this case, the opener position) before the start of the engine (at the time of non-control), and stored as reference position learning.

If any one of the determinations in steps S24 to S26 is negative, the routine is terminated without performing the subsequent processing.

After execution of step S27, step S28
The value of learning counter in determines whether a T _1. If the value of the learning counter is T _1, step S2
In step 9, the learning completion flag is set to ON, and the reference position learning routine ends. Further, if the value is T ₁ of the learning counter is determined in step S28, ON learning completion flag
Without exiting this routine.

As described above, after the IG-ON, the reference position learning is performed in a range where the value of the learning counter is "T ₀ <counter value <T ₁ ". Here, T ₀ is a time from when the power is turned on until the sensor power is stabilized, and is provided to prevent erroneous learning due to a variation in each sensor output when the sensor power is turned on. Further, T ₁ is a predetermined time width after the lapse of T ₀ , and is a time for detecting each sensor output several times during this time to ensure learning.
If the learning completion flag has not been turned on even though the predetermined time (T ₁ ) has elapsed, the previous reference position learning value is adopted (step S30).

Next, the process of raising the reference position learning value according to one embodiment of the present invention will be described. According to the present embodiment, after the throttle control is started, the reference position is corrected as follows. FIG. 4 is a flowchart showing a processing routine for raising the reference position learning value of the throttle control according to one embodiment of the present invention. As shown in FIG. 4, first, in step S40, it is determined whether or not the raising process is being performed. If the raising process is being performed, the process jumps to a raising amount attenuation routine (described later) after step S50.

If it is determined in step S40 that the raising process has not been executed, the conditions for executing the raising process (steps S41 to S43) are as follows.
And that the ISC control is not being executed) is established. When the vehicle is running, raising the reference position of the throttle control has little effect on the vehicle behavior.

First, in step S41, it is determined whether the vehicle speed is higher than a predetermined value, and in step S42, it is determined whether the engine speed Ne is higher than a predetermined value. Then, in a step S43, it is determined whether or not the ISC control is being executed. Steps S41 and S42
If the determination in step S43 is affirmative and the determination in step S43 is negative, a raising process is performed in step S44.

In step S44, the reference position learned value learned at the time of IG-ON (or the reference position set by adopting the previous value) is set as the base reference position, and the raising amount α is added to this base reference position. Thus, a control reference position used for throttle control is obtained. Step S4
After the execution of the raising process of No. 4, the raising flag is turned ON in step S45, and the current routine ends. That is, after the execution of the raising process in step S44, the determination in step S40 from the next routine indicates that the raising is being performed.

If the result of determination in step S40 is that raising is being performed, the raising amount is attenuated in the following manner.

First, in step S50, it is determined whether or not the accelerator is depressed. This determination is made, for example, by the accelerator opening AP obtained from the accelerator opening sensor.
Is smaller than a predetermined value. When the accelerator opening AP is equal to or more than a predetermined value, that is, when the accelerator is depressed, the raising amount is set to “0”. That is, in step S55, the control reference position is set as the base reference position. Thus, when the accelerator is depressed by the driver during traveling or during deceleration from the traveling state, it is possible to prevent the engine speed from excessively increasing due to raising.

After the control reference position is set to the base reference position in step S55, the raising execution flag is cleared (OFF) in step S56, and this routine ends.

If it is determined in step S50 that the accelerator opening AP is smaller than the predetermined value, it is determined in step S51 whether or not the ISC feedback control is being performed. Further, in step S52, the rotation of the engine is stable (that is, the rotation of the engine is stable). It is determined whether or not the change in the engine speed Ne is sufficiently small.

If any one of the determination results in steps S51 and S52 is negative, this routine ends without performing the subsequent processing.

If the results of the determinations in steps S51 and S52 are both affirmative, that is, if the ISC feedback control is currently being performed and the rotation of the engine is stable, a damping process of the raising amount α is executed in steps S53 and S54. .

First, in step S53, a predetermined amount β (however, from the current control reference position (control reference position _i )).
β <α) is subtracted, and it is determined whether the value is larger than the base reference position. If the subtracted value is larger than the base reference position, in step S54, a predetermined amount β from the previous control reference position (control reference position _i-1 ).
Is subtracted to calculate the current control reference position. That is, the corresponding current raising amount α _i is attenuated to a value obtained by subtracting the predetermined value β from the previous raising amount α _i−1 , and this routine ends.

If the value obtained by the subtraction in step S53 is equal to or smaller than the base reference position, it is determined that the attenuating process of the raising amount has been completed, and the control reference position is set to the base reference position in step S55.
Then, the raising execution flag is cleared (OFF), and this routine ends.

The control reference position, which has been raised, is returned to the base reference position during execution of the ISC feedback control by the attenuation processing of the raising amount. This prevents the amount of raising from being absorbed in the learning term of the ISC feedback control.

Next, the throttle control according to the present embodiment will be described in comparison with a conventional throttle valve control device having no raising process.

FIGS. 5A to 5E are timing charts showing throttle control by the conventional throttle valve control device. As shown in FIG. 5C, in the conventional throttle valve control device, the raising process is not performed and the IG
-The control reference position learned at the time of ON is continuously used. After the IG-ON, as shown in FIG. 5B, it is assumed that the temperature of the throttle sensor has decreased due to the traveling wind or the like caused by the traveling of the vehicle. In this case, when the vehicle is decelerated from the running state (FIGS. 5A and 5D), the throttle valve 10 is controlled to close due to an error in the reference position due to the temperature characteristics of the throttle sensor 13 and the like. A deviation (Δθ) occurs in the degree TA. This difference in throttle opening TA (Δ
θ) causes the engine speed Ne to decrease more than necessary, and in some cases, engine stall (FIG. 5E).

FIGS. 6A to 6E are timing charts showing throttle control for performing a raising process in the throttle valve control device according to one embodiment of the present invention. As shown in FIG. 6C, the time when the vehicle is determined to be in the running state (the above-described steps S41 to S43)
Thus, the control reference position learned at the time of IG-ON is raised by a predetermined raising amount α.

Therefore, after the IG-ON, the temperature of the throttle sensor is lowered due to the running of the vehicle (see FIG. 6).
(B)), even if the deceleration (FIGS. 6 (a) and (d)) is performed, it is possible to prevent a decrease in the engine speed Ne due to an error in the reference position due to the temperature characteristics of the throttle sensor 13 (FIG. 6).
(E)). Further, as shown in FIG.
When the SC feedback control is executed (and the engine speed Ne is in a stable state), the rising amount is gradually attenuated, so that the engine speed Ne during the idling operation can be prevented from excessively increasing.

[0044]

As described above, according to the throttle valve control apparatus for an internal combustion engine of the present invention, by raising the reference position of the throttle control during vehicle running,
It is possible to prevent a decrease in the engine speed at the time of engine deceleration caused by an error due to the influence of the temperature characteristics of the throttle sensor and the like without greatly affecting the vehicle behavior.

Further, the raising amount is attenuated when the engine speed during the ISC control is stabilized, thereby preventing an increase in the engine speed during idling operation due to excessive raising and a deviation of a learning term of the ISC control. can do.

Further, when the accelerator pedal is depressed beyond a predetermined opening, the raising amount is set to zero, so that
It is possible to prevent the engine speed from increasing more than necessary when the accelerator is depressed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a throttle valve control device for an internal combustion engine according to one embodiment of the present invention.

FIG. 2 is a flowchart showing throttle control according to one embodiment of the present invention.

FIG. 3 is a flowchart showing a routine for learning a reference position in the throttle valve control device according to the embodiment.

FIG. 4 is a flowchart showing a routine for raising a reference position learning value for throttle control according to one embodiment of the present invention;

FIGS. 5A to 5E are timing charts showing throttle control by a conventional throttle valve control device.

6 (a) to 6 (e) are timing charts showing throttle control for performing a raising process in a throttle valve control device according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Throttle valve 11 DC motor 12 Clutch 13 Throttle sensor 14 Opener 15 Spring 16 Throttle fully closed stopper 17 ECU 100 Throttle valve control device

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI F02D 41/14 310 F02D 41/14 310L 45/00 340 45/00 340C (72) Inventor Osamu Fukasawa 1 Showacho, Kariya City, Aichi Prefecture 1-chome Inside DENSO Corporation

Claims (3)

[Claims] 1. A throttle valve control device for an internal combustion engine having an electronically controlled throttle valve, wherein the throttle valve control device outputs an output value of a throttle sensor when the throttle valve is at a reference position when an ignition is turned on. And a control means for controlling the throttle valve based on the reference position learning value. A throttle valve control device for an internal combustion engine, comprising: a determination unit configured to determine whether the vehicle is traveling; and a correction unit that sets a value obtained by raising the reference position learning value to a reference position learning value when it is determined that the vehicle is traveling. 2. The control unit performs a feedback control of a throttle valve opening so that an engine speed during idling becomes a target engine speed, and the correction unit attenuates a raising amount during the feedback control. Item 3. The throttle valve control device for an internal combustion engine according to Item 1. 3. The throttle valve control device for an internal combustion engine according to claim 1, wherein said correcting means sets the raising amount to zero when the accelerator opening is equal to or more than a predetermined value.