JP2001090575A - Throttle control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent improper behavior near an intermediate stopper in a change in opening of a throttle valve with an electronic throttle system. SOLUTION: An actual throttle opening as the actual opening of a throttle valve 5 is compared with a learning value corresponding to an intermediate stopper, and a drift of the learning value TG as the opening of the throttle valve 5 corresponding to the intermediate stopper is judged on condition that a current flowing in a torque motor 19 is positive directed basically when the actual throttle opening is larger or the current flowing in the torque motor 19 is negative directed basically when the actual throttle opening is smaller. The learning value TG is corrected to match the direction of a current to be output to the torque motor 19 corresponding to the intermediate stopper. This prevents improper behavior such as overshoot or hunting near the intermediate stopper in a change in opening of the throttle valve 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle control device for an internal combustion engine that controls an opening degree of a throttle valve by driving an actuator according to an accelerator operation amount or the like.

[0002]

2. Description of the Related Art In recent years, a throttle control device for an internal combustion engine called an "electronic throttle system" for controlling a throttle valve opening by driving a motor as an actuator in accordance with an accelerator operation amount or the like has been adopted. I have. In such an electronic throttle system, for example, a current flows to a motor in accordance with an accelerator opening signal from an accelerator opening sensor that detects the amount of depression of an accelerator pedal, and the throttle valve is opened and closed by driving the motor. The amount of air supplied to the internal combustion engine is controlled.

In the above-mentioned electronic throttle system, even when the supply of current to the motor is stopped for some reason,
By mechanically holding the opening of the throttle valve at a predetermined intermediate position between the fully closed position and the fully opened position (hereinafter referred to as an “intermediate stopper position”) by utilizing different biasing forces of a plurality of springs, 2. Description of the Related Art There has been known a vehicle in which an internal combustion engine can be evacuated without immediately stopping.

Here, when the opening of the throttle valve is opened from the intermediate stopper position in the normal state of the electronic throttle system, the motor is rotated in a predetermined direction against the urging force of one of the springs. When closing the opening of the throttle valve from the intermediate stopper position, the motor is rotated in a direction opposite to the predetermined direction against the urging force of the other spring. At this time, the directions of the currents flowing through the motors are opposite to each other with respect to the intermediate stopper position.

[0005]

In the electronic throttle system described above, the direction of the control current for maintaining the throttle valve in a steady state reverses the direction of the intermediate stopper position, and its magnitude corresponds to the biasing force of the spring. It will be. Therefore, for example, when the throttle valve passes through the intermediate stopper position from a position closer to the intermediate stopper position to the position closer to the open side than the intermediate stopper position, the opening change that does not pass through the intermediate stopper position is changed. A larger change in the control current is required. Therefore, when the target opening is given so that the throttle valve passes through the intermediate stopper position, it is effective to give the control current after passing through the intermediate stopper position with expectation. However, if there is any deviation between the stored value of the opening degree of the throttle valve initially set in correspondence with the intermediate stopper position and the current detected value, the intermediate stopper position is not actually passed. Nevertheless, an expected control current for passing through the intermediate stopper position is given to cause an overshoot, or an expected control current cannot be given despite actually passing through the intermediate stopper position. There is a problem that inappropriate behavior such as deterioration of responsiveness is caused.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve such a problem, and a throttle control of an internal combustion engine capable of preventing inappropriate behavior near an intermediate stopper position due to a change in opening of a throttle valve by an electronic throttle system. The task is to provide devices.

[0007]

According to the throttle control device for an internal combustion engine of the present invention, the learning value correction means corresponds to the current opening of the throttle valve by the opening detection means and the intermediate position by the position holding mechanism. The magnitude relationship with the learning value stored in advance is compared, and at this time, if the direction of the current which should originally flow through the actuator is wrong, it is determined that the learning value is shifted for some reason, and The learning value is corrected so that the direction of the current output to the actuator matches. This prevents an inappropriate behavior such as overshoot or hunting near the intermediate position in the change in the opening of the throttle valve by the electronic throttle system.

According to the second aspect of the present invention, the learning value correcting means in the throttle control device for an internal combustion engine is provided when the throttle valve is not operating in an acceleration / deceleration state and the opening of the throttle valve can be detected stably. Is corrected.
As a result, the reliability of the learning value can be enhanced, and inappropriate behavior near the intermediate position in the change of the opening of the throttle valve by the electronic throttle system can be reliably prevented.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.

FIG. 1 is a schematic configuration diagram showing an internal combustion engine to which a throttle control device for an internal combustion engine according to an embodiment of the present invention is applied, and peripheral devices thereof.

In FIG. 1, an air cleaner 3 is provided upstream of an intake passage 2 of an internal combustion engine 1.
An air flow meter 4 for detecting an intake air amount (intake air amount) is installed on the downstream side of the air flow meter. Further, a throttle valve 5 is provided downstream of the air flow meter 4 in the intake passage 2, and the actual opening of the throttle valve 5 is determined by the driving force of a torque motor 19 connected to a rotation shaft 5 a of the throttle valve 5. A certain actual throttle opening TA is controlled, and the amount of intake air supplied to the internal combustion engine 1 is adjusted. The actual throttle opening TA of the throttle valve 5 is detected by a throttle opening sensor 16. It should be noted that even during idling, the actual throttle opening TA is controlled by the driving force of the torque motor 19, whereby the intake air amount GN
And feedback control is performed such that the engine speed NE matches the target idle speed. Further, the intake passage 2 is connected to each cylinder of the internal combustion engine 1 via an intake manifold 6, and intake air from the intake passage 2 is distributed and supplied to each cylinder via the inside of the intake manifold 6.

Intake manifolds 6 are provided with injectors 7 corresponding to the respective cylinders, and the fuel injected from the respective injectors 7 is mixed with intake air and supplied to the respective cylinders. This air-fuel mixture is introduced into the combustion chamber 9 of each cylinder as the intake valve 8 opens and closes, is burned by the ignition of a spark plug 10, pushes down a piston 11, and applies torque to a crankshaft 12. The exhaust gas after combustion is discharged to the outside via an exhaust passage 14 with opening and closing of an exhaust valve 13. A crank angle sensor 15 is provided at a position close to the crankshaft 12, and a pulse signal is output from the crank angle sensor 15 at every 30 ° CA (Crank Angle).

Reference numeral 20 denotes an ECU (Electronic Control Unit).
The ECU 20 controls the driving of the injector 7 based on the intake air amount GN signal detected by the air flow meter 4 and the engine speed NE signal detected by the crank angle sensor 15, and controls the throttle opening sensor CPU that controls opening and closing of the throttle valve 5 based on the actual throttle opening TA signal detected by the accelerator pedal 16 and the accelerator opening Ap signal detected by the accelerator opening sensor 18 based on the amount of depression of the accelerator pedal 17.
The microcomputer mainly comprises a microcomputer 21, a ROM 22, a RAM 23, and the like.

Next, the configuration of the ECU 20 and its surroundings will be described in more detail with reference to FIG.

In the ECU 20, a CPU 21 reads an intake air amount GN signal, an engine speed NE signal, an actual throttle opening degree TA signal, an accelerator opening degree Ap signal, and the like, and requests each time according to the operating state of the internal combustion engine 1. This is a well-known central processing unit that calculates a fuel injection amount of the injector 7 and a target throttle opening TTP, which is a target command value of the throttle valve 5 by the torque motor 19, and the like.

The ROM 22 is a so-called program memory in which various control programs for controlling the operating state of the internal combustion engine 1, that is, a fuel injection control program, a throttle control program, and the like are stored in advance.
The CPU 21 executes various arithmetic processes in accordance with the program stored in the ROM 22. Also, RA
M23 is a so-called data memory that temporarily stores input / output data of various sensors, calculation processing data by the CPU 21, and the like.

The injector drive circuit 24 has an intake air amount GN
This is a circuit for driving the injector 7 by forming a signal of a predetermined pulse width corresponding to the fuel injection amount calculated through the CPU 21 based on the signal and the engine speed NE signal. As a result, an amount of fuel corresponding to the calculated fuel injection amount is injected and supplied from the injector 7 to each cylinder of the internal combustion engine 1.

The motor drive circuit 25 is connected to a later-described CP.
In accordance with the calculation process by U21, in accordance with the deviation between the target throttle opening TTP of the throttle valve 5 by the torque motor 19 and the actual throttle opening TA from the throttle opening sensor 16, PWM (pulse width modulation) is used to reduce the deviation. ) A circuit for forming an output current DUTY from an output DUTY (control amount) calculated as a converted duty ratio signal and outputting the output current DUTY to the torque motor 19. As a result, a driving force corresponding to the output current DUTY is generated in the torque motor 19, and the actual throttle opening TA of the throttle valve 5 detected by the throttle opening sensor 16 finally matches the target throttle opening TTP. It is adjusted to.

The A / D conversion circuit 27 converts the read intake air amount GN signal, the actual throttle opening TA signal, the accelerator opening Ap signal, the cooling water temperature THW signal from a water temperature sensor (not shown), and the like. A circuit for A / D (analog-digital) conversion and output to the CPU 21.

Next, the configuration of the throttle control device for the internal combustion engine will be described with reference to FIGS.

2 and 3, the accelerator pedal 1
An accelerator opening sensor 18 is provided in 7, and the accelerator pedal 17 is connected to an accelerator lever 41. The accelerator lever 41 is connected to the accelerator return spring 4
The accelerator pedal 17 is urged in the return direction (clockwise direction) by the accelerator pedals 2a and 42b. Accelerator pedal 1
7 is not operated (accelerator OFF), the accelerator lever 41 is pressed by the accelerator return springs 42a, 4b.
2b, it is held in a state of contact with the accelerator fully closed stopper 43. While the internal combustion engine 1 is operating, the position of the accelerator lever 41 based on the operation amount of the accelerator pedal 17 is detected by the accelerator opening sensor 18 as the accelerator opening Ap.

On the other hand, a valve lever 44 is connected to the rotary shaft 5a of the throttle valve 5, and this valve lever 44
Is urged in the opening direction of the throttle valve 5 (upward in FIG. 2) by the retreat running spring 45. For this reason, the motor OFF (torque motor 19) shown in FIG.
When the power is turned off, the retreating spring 45 holds the valve lever 44 at the intermediate stopper position where it contacts the intermediate lever 47. At this time, the intermediate lever 4
7 is urged by a valve return spring 48 in the closing direction of the throttle valve 5 (downward in FIG. 2), and is in contact with an intermediate stopper 49.

That is, the pulling force of the valve return spring 48 is set to be larger than the pulling force of the retreat running spring 45. Therefore, when the motor is turned off as shown in FIG. 2B, the pulling force of the valve return spring 48 overcomes the pulling force of the retreat running spring 45, and the intermediate lever 47 comes into contact with the intermediate stopper 49 and is held. Is held at the intermediate stopper position (actual throttle opening TA = about 3 °) regulated by the intermediate stopper 49.

On the other hand, during normal control (motor ON) shown in FIG. 2A, the torque motor 19 rotates forward or reverse according to the operation amount of the accelerator pedal 17, and the actual throttle opening TA of the throttle valve 5 Is adjusted, and the actual throttle opening TA of the throttle valve 5 at that time is detected by the throttle opening sensor 16. At this time, when increasing the actual throttle opening TA, the torque motor 19 is required.
When the motor motor on the positive side is supplied to the motor and the torque motor 19 is rotated forward, as shown in FIG.
4, the intermediate lever 47 is pushed up against the pulling force of the valve return spring 48, and the throttle valve 5 is driven in the opening direction. Conversely, when the actual throttle opening TA is reduced, a negative motor current is supplied to the torque motor 19 and the torque motor 19 is rotated in the reverse direction.
The valve lever 44 is lowered, and the throttle valve 5 is driven in the closing direction. When the throttle lever 5 is driven in the closing direction after the intermediate lever 47 is brought into contact with the intermediate stopper 49, the valve lever 44 is lowered against the pulling force of the retreating spring 45, and the throttle valve 5 is fully closed. When the valve lever 44 is closed to the stopper position (actual throttle opening degree TA = 0 °), the throttle fully closed stopper 4
6 to prevent further rotation.

Next, the structure of the torque motor 19 connected to the rotary shaft 5a of the throttle valve 5 used in the throttle control device for an internal combustion engine according to one embodiment of the present invention will be described with reference to FIGS. This will be described with reference to FIG. FIG. 5 is a diagram showing the torque motor 19 shown in FIG.
FIG. 3 is a view taken in the direction of arrow A with 3 removed.

As shown in FIG. 4, a throttle valve 5 is rotatably supported by bearings 61 and 62 on a throttle body 60 disposed in the middle of the intake passage 2. The throttle valve 5 is formed in a disk shape, and is fixed to the rotating shaft 5a with screws. By rotating the throttle valve 5 together with the rotation shaft 5a, the flow passage area of the intake flow passage 60a formed by the inner wall of the throttle body 60 is adjusted, and the amount of intake air passing through the intake passage 2 is controlled. You.

A valve lever 44 is press-fitted and fixed to one end of the rotary shaft 5a of the throttle valve 5, and is rotated together with the rotary shaft 5a. This valve lever 4
The fully closed position of the throttle valve 5 is defined by the contact of the throttle valve 4 with the throttle fully closed stopper 46. In addition,
By changing the screwing amount of the throttle fully closed stopper 46, the fully closed position of the throttle valve 5 is adjusted. In FIG. 4, the evacuation travel spring 45 and the like are omitted.

The throttle opening sensor 16 is disposed further to the end of the rotary shaft 5a than the valve lever 44,
It comprises a contact portion 16a, a substrate 16b coated with a resistor, and a housing 16c. The contact portion 16a is press-fitted into the rotating shaft 5a, and is rotated together with the rotating shaft 5a. The board 16b is fixed to the housing 16c, and the contact portion 16a slides on the resistor applied to the board 16b. A constant voltage of 5 [V] is applied to the resistor applied to the substrate 16b. The sliding position between the resistor and the contact portion 16a is changed according to the opening of the throttle valve 5, and the output voltage value is changed. Is varied. The output voltage value from the throttle opening sensor 16 is input to the ECU 20, and the actual throttle opening TA of the throttle valve 5 is detected.

Further, as shown in FIGS. 4 and 5, the torque motor 19 is connected to the other end of the rotating shaft 5a by a rotor 65, a core 69, and a pair of solenoids 70 and 75. The end of the torque motor 19 is covered by a cover 63. The rotor 65 is composed of an iron core 66 and permanent magnets 67 and 68 press-fitted and fixed to the rotating shaft 5a, and is rotatably housed in a housing hole 69a formed by the inner wall of the core 69. The iron core 66 is formed in a cylindrical shape, and is press-fitted and fixed to the other end of the rotating shaft 5a. The permanent magnets 67 and 68 are formed in an arc shape, and
Are attached and fixed at equal intervals on the outer periphery of. Since the rotation range of the throttle valve 5 is usually 90 ° or less, the arc length of the permanent magnets 67 and 68 is long enough to allow a torque capable of rotating the rotor 65 within the rotation range of the throttle valve 5. Good. The permanent magnets 67 and 68 are neodymium-based.
A so-called samarium-cobalt system that generates high magnetic force,
Rare earth magnets are employed.

The core 69 is made of a thin plate made of a magnetic material.
The rotor 65 is rotatably housed in the housing hole 69a. The core 69 is formed in a slotless manner around the rotor 65 without any break. The solenoids 70 and 75 are formed by winding coils 72 and 77 around iron cores 71 and 76, respectively, and are press-fitted and fixed to a core 69. Coil 72, 7
7 is supplied with a control current from a pin 81 embedded in a connector 80. Also, the valve return spring 48
Has one end fixed to the iron core 66 and the other end fixed to the screw 64, and the valve return spring 48 urges the throttle valve 5 to the closed side.

Next, E used in a throttle control device for an internal combustion engine according to an embodiment of the present invention will be described.
A description will be given based on a block diagram of FIG. 6 showing a processing procedure of the throttle control in the CPU 21 in the CU 20.

In FIG. 6, first, in a target throttle opening calculation process S1, a target throttle opening TTP is calculated based on the accelerator opening Ap [°] from the accelerator opening sensor 18.
[°] is calculated. In the following provisional target throttle opening calculation processing S2, the target throttle opening TTP [°] calculated in the target throttle opening calculation processing S1 is smoothed, and the provisional target throttle opening TTPsm [°] is calculated. Is calculated. In the acceleration / deceleration torque calculation process S3, the provisional target throttle opening TTPsm [°] calculated in the provisional target throttle opening calculation process S2 and the throttle opening sensor 1 are used.
6, the acceleration / deceleration torque Tg [N · m] of the throttle control system is calculated based on the deviation from the actual throttle opening TA [°] from 6 and the actual throttle speed ΔTA which is the current throttle speed.

In the spring torque calculation processing S4, the spring torque Ts [N] is determined according to the provisional target throttle opening TTPsm [°] calculated in the provisional target throttle opening calculation processing S2.
M] is calculated. Here, the provisional target throttle opening T
While calculating the spring torque Ts according to TPsm,
On the open side where the actual throttle opening TA is larger than the intermediate stopper position, it corresponds to the valve return spring 48,
On the closed side where the actual throttle opening TA is smaller than the intermediate stopper position, the retracted traveling spring 45 is used. Alternatively, the spring torque may be calculated according to the predicted throttle opening based on the actual throttle opening, the actual throttle speed, and the actual throttle acceleration instead of the provisional target throttle opening TTPsm.

In the friction torque calculation process S5, the provisional target throttle opening TTPsm [°] and the actual throttle opening T
A [°] and the estimated motor temperature Tm calculated in the subsequent stage
[° C.], bearings 61 and 62 according to the frictional state at that time.
Friction torque Tf of throttle control system [Nm]
Is calculated. Then, the acceleration / deceleration torque Tg [N · m], the spring torque Ts [N · m] and the friction torque Tf [N · m] calculated in the preceding stage are added to obtain the required torque TR [N · m] of the torque motor 19. Is calculated.

In the motor current calculation processing S6, TR = f
Based on the measured values using the inverse model formula of (TA, IM),
Using the required torque TR [N · m] calculated in the preceding stage as a parameter, the required current IM required to generate each required torque
[A] is calculated according to the actual throttle opening TA [°]. In the next current responsiveness compensation process S7, the required current IM [A] calculated in the preceding stage is delayed due to inductance or resistance due to a coil or wiring (wire harness) or the like unique to the torque motor 19, Current (compensation value) [A] calculated in consideration of the estimated current Ia [A], the estimated resistance Rsm [Ω], and the estimated motor temperature Tm [° C], which are calculated in a later stage so as to compensate for the difference, and the original request. Current IM
[A] is added to calculate the output current Io [A].

In the back electromotive voltage calculation process S8, the output current Io [A] calculated in the preceding stage, the estimated motor temperature Tm [° C] calculated in the following stage, and the actual throttle opening TA [°].
The back electromotive force Ve [V] is calculated according to the tentative target throttle opening TTPsm [°]. Further, in the output duty calculation processing S9, the output current Io [A] calculated in the preceding stage is obtained.
Is added to the current value in consideration of the back electromotive voltage Ve [V], and the estimated resistance Rsm [Ω] and the battery voltage VB [V] calculated in the subsequent stage are taken into consideration. A possible output DUTY is calculated. Further, in the motor drive circuit 25, an output current DUTY for outputting to the torque motor 19 is formed based on the output DUTY from the output DUTY calculation processing S9.

Here, the output duty that can be output is, for example, 3 to 90% and 100%. Note that 0
３3%, 90-100%, and 100% or more are DUTY ranges that cannot be output on a circuit. This output DU
TY is output to the motor drive circuit 25 and the output current DUTY
Is formed and output to the torque motor 19 to drive the torque motor 19, so that the actual throttle opening TA detected by the throttle opening sensor 16 is finally adjusted to match the target throttle opening TTP. .

As described above, the output duty calculation processing S9
Therefore, there is an output DUTY that cannot be output due to the operation restriction of the motor drive circuit 25 with respect to the required DUTY. For example, since a DUTY range of 0 to 3% cannot be output, when 0 to 3% is requested, the output DUTY
Is set to 3 [%]. When a DUTY range of 3 to 90 [%] is requested, the output DUTY corresponding to the value is set. Also, since a duty range of 90 to 100% cannot be output, when a duty range of 90 to 100% is required, 90 to 95% is 90%.
[%] And 95 to 100 [%], it is 100 [%]. When the operation result is requested to be 100% or more, the output DUTY becomes 100 because output is impossible.
[%].

As described above, the request DUTY and the output DUTY
Therefore, it is necessary to estimate the actually flowing current based on the output DUTY. Therefore, in the current estimation calculation process S10, the output DUTY calculation process S9
From the output DUTY, the battery voltage VB [V], and the estimated resistance Rsm [Ω] calculated in the subsequent stage.
[A] is calculated.

In the following resistance estimation calculation processing S11, the estimated current Ia [A] from the current estimation calculation processing S10, and the actual current flowing in the torque motor 19 at that time is the actual current IH detected by the hardware circuit in the ECU 20. A smoothing process is performed on the instantaneous true resistance calculated from [A], and the estimated resistance Rsm [Ω] is calculated. Then, in the motor temperature estimation calculation processing S12, the resistance estimation calculation processing S11
Motor temperature Tm based on the estimated resistance Rsm [Ω]
[° C.] is calculated. As a result, a change in motor torque, a change in magnetic flux density, a change in friction torque, and the like due to a change in motor temperature are corrected, and an appropriate output DUTY to be output to the motor drive circuit 25 is obtained.

Next, E used in the throttle control device for the internal combustion engine according to one embodiment of the embodiment of the present invention.
A description will be given based on a flowchart of FIG. 7 showing a processing procedure of intermediate stopper position learning in the CPU 21 in the CU 20. This intermediate stopper position learning routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

In FIG. 7, first, in step S101,
It is determined whether the throttle valve 5 is in the acceleration / deceleration state. When the determination condition of step S101 is satisfied, that is, when the throttle valve 5 is moving, the actual throttle opening TA [°] fluctuates every moment, and the torque motor 19
The direction of the motor current flowing through the motor also fluctuates, and the learning value TG for the intermediate stopper position stored in the memory in advance is changed.
This routine ends without performing anything because the update of [°] is impossible. On the other hand, when the determination condition of step S101 is not satisfied, that is, when the throttle valve 5 is stable in a steady state, the process proceeds to step S102, where the learning value TG [°] for the intermediate stopper position and the current actual throttle opening TA It is determined whether or not [°] is equal. Step S
When the determination condition of 102 is satisfied, that is, when the learning value TG [°] is equal to the actual throttle opening TA [°], it is impossible to make a true / false determination of the learning value TG [°] based on the direction in which the motor current flows, which will be described later. This routine ends without doing anything.

On the other hand, when the determination condition of step S102 is not satisfied, that is, when the learning value TG [°] is not equal to the actual throttle opening TA [°], step S103 is performed.
And the actual throttle opening TA [°] becomes the learning value TG.
It is determined whether it exceeds [°]. Step S103
Is satisfied, that is, the actual throttle opening TA [°]
Is greater than the learning value TG [°] and is on the open side, the process proceeds to step S104, and it is determined whether the motor current is negative. The determination condition of step S104 is satisfied, that is,
When the motor current flowing through the torque motor 19 is minus, the process proceeds to step S105. Step S10
At 5, the actual throttle opening TA [°] is equal to the learning value TG.
When the motor current flowing through the torque motor 19 exceeds [°] and is on the open side, the learning value TG [°] is deviated for some reason that the motor current flowing through the torque motor 19 should be positive (positive) but negative (negative). For this reason, it is determined that the correction to the open side is necessary, and the learning value TG [°] so far is set to the predetermined value α.
[°] is added to update the learning value TG [°], and this routine ends. If the condition of step S104 is not satisfied, that is, if the motor current flowing through the torque motor 19 is positive, the actual throttle opening TA
Since [°] exceeds the learning value TG [°] and is the same as the original current direction when it is on the open side, this routine ends without performing any operation.

On the other hand, the condition of step S103 is not satisfied, that is, the actual throttle opening TA [°] is equal to the learning value TG.
If it is less than [°] and it is on the closed side, the process proceeds to step S106, and it is determined whether the motor current is positive. The determination condition of step S106 is satisfied, that is, the torque motor 1
When the motor current flowing through No. 9 is positive, the process proceeds to step S107. In step S107, when the actual throttle opening TA [°] is smaller than the learning value TG [°] and is on the closing side, the learning value TG is that the motor current flowing through the torque motor 19 should be minus when it should be minus.
[°] is considered to have been shifted for some reason, and needs to be corrected to the closed side.
A predetermined value α [°] is subtracted from [°] to obtain a learning value TG.
[°] is updated, and this routine ends. When the determination condition of step S106 is not satisfied, that is, when the motor current flowing through the torque motor 19 is minus,
Since the actual throttle opening TA [°] is less than the learned value TG [°] and is the same as the original current direction when the throttle is closed, the routine ends without any operation.

As described above, the throttle control device for an internal combustion engine according to the present embodiment outputs the output current DUTY corresponding to the output DUTY (control amount) calculated based on various sensor signals to control the torque motor 19 as an actuator. A CPU 21 in the ECU 20 for driving and controlling the actual throttle opening TA of the throttle valve 5, a throttle control means achieved by a motor drive circuit 25, and a torque motor 19.
A current detecting means achieved by the CPU 21 in the ECU 20 for detecting a current flowing through the ECU 20, a throttle opening sensor 16 as an opening detecting means for detecting the actual throttle opening TA of the throttle valve 5, and a torque motor 19 When no current is output in either the positive or negative direction, the valve lever 44 for holding the actual throttle opening TA of the throttle valve 5 at an intermediate stopper position between the fully closed position and the fully opened position, 45, middle lever 4
7. Valve return spring 48 and intermediate stopper 4
9, a magnitude relationship between a learning value TG stored in advance as the opening of the throttle valve 5 corresponding to the intermediate stopper position and the current actual throttle opening TA of the throttle valve 5, and a torque at that time. ECU for correcting learning value TG based on direction of current flowing through motor 19
And a learning value correcting means achieved by the CPU 21 in the CPU 20.

That is, the actual throttle opening TA of the throttle valve 5 is compared with the learning value TG corresponding to the intermediate stopper position, and when the actual throttle opening TA is larger, the direction of the current flowing through the torque motor 19 becomes the original plus. Or when the actual throttle opening TA is smaller, the learning value TG as the opening of the throttle valve 5 corresponding to the intermediate stopper position is determined based on whether the direction of the current flowing through the torque motor 19 is the original minus direction. The deviation is determined.
Based on the determination result, the learning value TG is corrected so that the direction of the current output to the torque motor 19 matches the intermediate stopper position. As a result, it is possible to prevent inappropriate behavior such as overshoot or hunting near the intermediate stopper position due to a change in the opening of the throttle valve 5 due to the electronic throttle system.

The learning value correcting means achieved by the CPU 21 in the ECU 20 of the throttle control device for an internal combustion engine according to the present embodiment is used when the actual throttle opening TA of the throttle valve 5 is stable in a steady state. This is for correcting the learning value TG. That is, the learning value TG is corrected when the throttle valve 5 is not operating in the acceleration / deceleration state and the actual throttle opening TA can be stably detected. Thereby, the reliability of the learning value TG can be improved, and the throttle valve 5 by the electronic throttle system
Unsuitable behavior in the vicinity of the intermediate stopper position due to the change in the opening degree can be reliably prevented.

In the above embodiment, the motor current flowing through the torque motor 19 is used to determine the deviation of the learning value TG of the throttle valve 5 corresponding to the intermediate stopper position. However, the value of the integral term in feedback control by PID control (Proportional Integral Differential Control; proportional / integral / differential control) for the torque motor 19 may be used.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an internal combustion engine to which an internal combustion engine throttle control device according to an embodiment of the present invention is applied and peripheral devices thereof.

FIG. 2 is a schematic diagram showing a main configuration of a throttle control device for an internal combustion engine according to an example of an embodiment of the present invention.

FIG. 3 is a perspective view showing a main configuration of a throttle control device for an internal combustion engine according to an example of the embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a configuration of a torque motor connected to a rotary shaft of a throttle valve used in a throttle control device for an internal combustion engine according to one embodiment of the present invention. .

FIG. 5 is an arrow view of the torque motor of FIG. 4 with the cover removed and viewed from the direction A.

FIG. 6 is an EC used in a throttle control device for an internal combustion engine according to an embodiment of the present invention.
FIG. 9 is a block diagram showing a processing procedure of throttle control in a CPU in U.

FIG. 7 is an EC used in a throttle control device for an internal combustion engine according to an example of an embodiment of the present invention.
9 is a flowchart showing a processing procedure of intermediate stopper position learning in the CPU in U.

[Explanation of symbols]

 Reference Signs List 1 internal combustion engine 5 throttle valve 16 throttle opening sensor 18 accelerator opening sensor 19 torque motor (actuator) 20 ECU (electronic control unit)

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 3G065 AA04 CA00 DA05 DA06 DA15 FA12 FA13 GA05 GA10 GA41 GA46 HA21 HA22 JA04 JA09 JA11 KA02 3G084 BA06 CA05 DA05 DA08 EB06 EB20 FA00 FA10 3G301 JA03 JA07 JA14 KA21 LA03 LC03 NA11 NC01ND PA11Z PG02Z

Claims (2)

[Claims] 1. A throttle control means for outputting a current corresponding to a control amount calculated based on various sensor signals to drive an actuator to control an opening of a throttle valve, and a current for detecting a current flowing through the actuator. Detecting means; opening degree detecting means for detecting the opening degree of the throttle valve; and when neither positive nor negative current is output to the actuator, the opening degree of the throttle valve is set to a fully closed position. A position holding mechanism for holding the throttle valve at a predetermined intermediate position between the fully open position and a learning value stored in advance as an opening degree of the throttle valve corresponding to the intermediate position and a current magnitude of the throttle valve; Learning value correction means for correcting the learning value based on the relationship and the direction of the current flowing through the actuator at that time. Throttle control apparatus for an internal combustion engine according to. 2. The throttle control of an internal combustion engine according to claim 1, wherein the learning value correction means corrects the learning value when the opening of the throttle valve is stable in a steady state. apparatus.