JPH0972231A - Throttle control device for internal combustion engine - Google Patents

Abstract

(57) Abstract: A throttle control device having a fail-safe function at the time of uncontrollable control avoids the occurrence of throttle valve hunting. SOLUTION: The opening of a throttle valve 5 is feedback-controlled through a DC motor 19 based on the outputs of a throttle sensor 16 and an accelerator sensor 17. At this time, the torque generated by the DC motor 19 is reversed in the vicinity of the position of the intermediate lever stopper 55 of the throttle valve 5 (F1, F2), and control hunting is likely to occur in the throttle valve 5 near the position. Therefore, when the clutch 18 is turned off, the intermediate lever stopper 5
5 is learned, and when the control command value of the throttle valve 5 becomes close to the learned position of the stopper 55,
The control command value is corrected to such an extent that torque reversal of the DC motor 19 is less likely to occur, and the throttle valve 5 is adjusted from the same position.
Move away from the control position of.

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, which electrically controls an opening of a throttle valve, which is an intake air amount adjusting valve of an on-vehicle internal combustion engine, through a motor or the like, and particularly controls the throttle valve. The present invention relates to implementation of a control device structure suitable for preventing hunting.

[0002]

2. Description of the Related Art A throttle control device that electrically controls the opening of a throttle valve can set the characteristics of the throttle opening with respect to the accelerator operation amount, so that the operating condition of the vehicle such as an acceleration request can be controlled. In recent years, it has attracted attention as a system that can respond accurately. FIG. 13 schematically shows the structure of an example of such a throttle control device.

As shown in FIG. 13, in the throttle control device, DC is applied via an electromagnetic clutch 18.
Power (torque) from the (DC) motor 19 is transmitted to the throttle valve 5. The drive of each of the electromagnetic clutch 18 and the DC motor 19 is controlled by an electronic control unit (not shown). In FIG. 13, the upper part of the drawing shows the opening direction of the throttle valve 5, and the lower part of the drawing shows the closing direction of the throttle valve 5.

On the other hand, the throttle valve 5 has a throttle sensor 16 for detecting the opening of the valve, and the accelerator sensor 1 for detecting the operation amount (opening) of the accelerator.
7 are provided respectively. Those sensors 16 and 1
Each of the outputs of 7 is taken into the electronic control unit (not shown), and the throttle opening and the accelerator operation amount are monitored.

Then, during the normal control in which the clutch 18 is turned on as shown in FIG. 13 (a), (1) the position of the accelerator lever 62 detected by the accelerator sensor 17 through the electronic control unit, That is, the accelerator operation amount (opening) and the opening of the throttle valve 5 detected by the throttle sensor 16 are taken in. (2) A control command value for the throttle valve 5 is calculated based on the loaded accelerator operation amount and throttle opening. (3) The motor 19 according to the calculated control command value
To open and close the throttle valve 5. Such feedback control is executed.

At this time, there is always a predetermined gap between the accelerator lever 62 biased in the closing direction by the accelerator return spring 61 and the intermediate lever 53 also biased in the closing direction by the valve return spring 51. The opening of the throttle valve 5 is controlled by the electronic control unit so that the opening is maintained.

The intermediate lever 53 has a balance with the valve lever 54 which is physically connected to the throttle valve 5 and is biased in the opening direction by the retracting spring 52. (a) In FIG. During the normal control shown, the valve lever 54 moves along with the movement thereof. (B) OFF of the clutch 18 shown in FIG. 13 (b)
At the time of (OFF), as described above, the retracting spring 52 is used.
The movement of the valve lever 54 biased in the opening direction is restricted by the. It is a lever that operates in such a manner.

In particular, when the clutch 18 is turned off, in order to realize the above restriction (b), the torque is controlled by the valve return spring 51 and the retreat travel spring 52 in the throttle control device. The relationship is set such that the torque of the valve return spring 51> the torque of the evacuation travel spring 52.

The operation of the device when the clutch 18 is turned off and the connection between the motor 19 and the throttle valve 5 is disconnected will be further described with reference to FIG. 13 (b).

When the electromagnetic clutch 18 is OFF and the accelerator operation amount (opening) is below a predetermined value,
The throttle valve 5 is held at the position of the intermediate lever stopper 55 in the manner shown in FIG. 13B based on the torque relationship between the valve return spring 51 and the retreat travel spring 52.

At this time, the accelerator lever 62
Since the above-described control relationship between the intermediate lever 53 and the intermediate lever 53 is also released, the accelerator lever 62 moves the intermediate lever 53 when the driver depresses the accelerator pedal to a predetermined value or more.
After that, the intermediate lever 53 is pushed up according to the amount of depression.

By pushing up the intermediate lever 53 in this way, the valve lever 54, which is biased in the opening direction by the retracting spring 52, follows the movement and moves in the opening direction. It follows that the valve will be opened. This is an operation mode used when so-called retreat traveling is performed as a fail safe when an abnormality or the like occurs in the throttle control device.

In this retreat traveling mode, when the driver releases his / her foot from the accelerator pedal, the accelerator lever 62 biased in the closing direction by the accelerator return spring 61 is returned to the position of the accelerator fully closed stopper 63. Accordingly, the throttle valve 5 also has a valve return spring 51 and a retracting travel spring 5.
Based on the above torque relationship with No. 2, the intermediate lever stopper 55 is returned to the position shown in FIG. 13 (b).

In FIGS. 13 (a) and 13 (b), the stopper 56 is a valve full-closed stopper arranged corresponding to the fully closed position of the throttle valve 5. In the throttle mechanism, as described above, when the electromagnetic clutch 18 is turned off, the throttle valve 5 is returned to the position of the intermediate lever stopper 55 slightly opened rather than the position of the valve fully closed stopper 56. I am trying to do it. This is the OF of the electromagnetic clutch 18.
This is to prevent a situation in which the throttle valve 5 is fully closed with F and the internal combustion engine suddenly stops.

Further, the throttle sensor 16 and the accelerator sensor 17 are assumed to be a dual system in which two sensor outputs are compared with each other. By adopting such a dual system as the throttle sensor 16 and the accelerator sensor 17, it becomes possible to appropriately deal with the failure of the sensors themselves.

[0016]

As described above, in the throttle control device for electrically controlling the opening of the throttle valve, the characteristic of the throttle opening with respect to the accelerator operation amount is calculated in the normal control. It can be arbitrarily set according to the control command value of the throttle valve. As described above, therefore, it becomes possible to appropriately respond to the driving state of the vehicle such as an acceleration request.

Further, in such a throttle control device, even when the electric throttle control is disabled due to a sensor failure or other causes, the electromagnetic clutch is turned off to set the retreat traveling mode to the above-mentioned mode. The minimum throttle operation will be secured.

However, according to the above configuration of the throttle control device, in the normal control in which the electromagnetic clutch 18 is turned on, as shown in FIG. 14, the throttle valve 5 is located near the position of the intermediate lever stopper 55. In the case of the control, the hunting of the valve 5 may occur due to the inversion of the drive torque by the DC motor 19. Hereinafter, such an operation mode of the apparatus will be described in detail.

For example, as shown in FIG. 14A, the throttle valve 5 has the intermediate lever stopper 55.
Assuming that the DC motor 19 is controlled to a position slightly lower (valve closing side) than the torque of the evacuation travel spring 52 that biases the throttle valve 5 upward (valve opening side). Torque F1 just enough to balance
Must occur on the valve closing side of.

On the contrary, as shown in FIG. 14B, the throttle valve 5 has the intermediate lever stopper 55.
Assuming that the DC motor 19 is controlled to a position slightly above (valve opening side), the torque of the valve return spring 51 that urges the throttle valve 5 downward (valve closing side) is It is necessary to generate a torque F2 on the valve-opening side of the valve 5 to balance the difference with the torque of the evacuation travel spring 52 biased to the upper side (valve-opening side).

As described above, in the throttle control device, the DC is separated by the position of the intermediate lever stopper 55.
The direction of the torque generated by the motor 19 is reversed. Therefore, if the throttle valve 5 is controlled near the position of the intermediate lever stopper 55, the DC motor 19
The generated torque may be repeatedly reversed, and when the motor torque is repeatedly reversed, the above control becomes difficult and hunting occurs in the throttle valve 5.

The present invention has been made in view of these circumstances, and a throttle control device for an internal combustion engine capable of preventing hunting of the throttle valve in the throttle mechanism and realizing more reliable throttle control. The purpose is to provide.

[0023]

In order to achieve such an object, in the invention according to claim 1, the first urging means for urging the throttle valve of the internal combustion engine in the valve closing direction and the throttle valve are opened. Second urging means for urging in the valve direction,
A throttle driving means for driving the throttle valve to open and close independently of the accelerator operation of the vehicle and against the biasing force of the first and second biasing means, and a throttle sensor for detecting the opening degree of the throttle valve. An accelerator sensor for detecting the accelerator operation amount, a clutch means for connecting and disconnecting the mechanical connection between the throttle drive means and the throttle valve, and a clutch control means for switching the connection / disconnection of the clutch means. Holding means for holding the throttle valve at a predetermined opening position by balancing the biasing forces of the first and second biasing means in a predetermined manner when the clutch means is controlled without connection. When the means is controlled to be connected, the front through the throttle drive means based on the output of each sensor. When the throttle control means for feedback controlling the opening / closing amount of the throttle valve and the clutch means are also controlled to be connected, the control command value of the throttle valve by the throttle control means is the holding value of the throttle valve. The throttle control device is configured to include a command value correction unit that corrects the control command value when the vicinity of the predetermined opening position held by the unit is indicated.

Further, in the invention according to claim 2, in the configuration of the invention according to claim 1, the command value correcting means comprises:
When the control command value increases in the vicinity of the predetermined opening position, the control command value is increased and corrected, and the control command value decreases in the vicinity of the predetermined opening position. The control command value is reduced and corrected.

According to the invention of claim 3, in the configuration of the invention of claim 1, the command value correcting means is
When the control command value is held near the predetermined opening position, the control command value is increased or decreased.

According to a fourth aspect of the invention, in the configuration of the invention according to the first aspect, the command value correction means is
When the control command value is near the predetermined opening position,
It is configured to correct the control gain of the throttle valve by the throttle control means so as to decrease it.

According to a fifth aspect of the present invention, in the configuration of the first aspect of the invention, the command value correction means is
When the control command value is near the predetermined opening position,
When the change in the accelerator operation amount is equal to or less than a predetermined value, the feedback control of the throttle control means is prohibited, and the throttle valve is held at the position.

Further, in the invention according to claim 6, in the configuration of the invention according to any one of claims 1 to 5, the command value correction means is set to a predetermined opening which is held by the holding means of the throttle valve. The degree position is learned, and the transition of the control command value to the vicinity of the predetermined opening position is detected based on the learned position.

The operation of each of these inventions is as follows. First, (a) first urging means for urging the throttle valve of the internal combustion engine in the valve closing direction of the invention according to claim 1. (B) Second biasing means for biasing the throttle valve in the opening direction. (C) Throttle drive means for opening and closing the throttle valve independently of the accelerator operation of the vehicle and against the biasing force of the first and second biasing means. (D) A throttle sensor that detects the opening of the throttle valve. (E) An accelerator sensor that detects the accelerator operation amount. (F) Clutch means for connecting and disconnecting the mechanical connection between the throttle drive means and the throttle valve. (G) Clutch control means for switching control of whether or not the clutch means is engaged. (H) Holding means for holding the throttle valve at a predetermined opening position by balancing the biasing forces of the first and second biasing means in a predetermined manner when the clutch means is controlled without engagement. (I) Throttle control means for feedback-controlling the opening / closing amount of the throttle valve through the throttle drive means based on the output of each sensor when the clutch means is controlled to be engaged. (J) Similarly, while the clutch means is controlled to be engaged, the throttle valve control command value by the throttle control means is in the vicinity of a predetermined opening position held by the holding means of the throttle valve. When indicated, a command value correction means for correcting the control command value. In the configuration including, the means (a), (b), and (h) are means for retracting the throttle valve to a safe position mainly when the clutch means is controlled without engagement. is there. Further, the above (c) to (g), and (i)
Each means of is a means mainly used in the normal control as the throttle control device.

Here, the throttle drive means of the above (c) is one for opening and closing the throttle valve against the urging force of the first and second urging means, although it is a normal control. From the above, the throttle valve is (h)
As described above, when the throttle valve is controlled near the predetermined opening position held by the holding means, the throttle valve hunting may be caused due to the inversion of the driving torque by the throttle driving means.

Therefore, in the invention according to claim 1, the command value correcting means of (j) is provided, and the control command value of the throttle valve by the throttle driving means of (c) is:
When the vicinity of the predetermined opening position held by the holding means (h) of the throttle valve is shown, the control command value is corrected.

Due to the correction of the control command value, the throttle valve to be controlled is in a state in which the inversion of the driving torque by the throttle driving means does not easily occur, for example, the throttle valve is forcibly removed from the vicinity of the predetermined opening position. The occurrence of the hunting can be preferably avoided.

According to the invention of claim 2,
The command value correcting means of the above (j): When the control command value increases in the vicinity of the predetermined opening position, the control command value is increased and corrected, and the control command value decreases. When the position becomes close to the predetermined opening position, the control command value is reduced and corrected. With this configuration, it is possible to preferably avoid the occurrence of hunting near the predetermined opening position when the throttle valve crosses the vicinity of the predetermined opening position and is controlled to open and close.

Further, as in the case of the same control structure, the opening degree of the throttle valve is step-corrected in the same direction according to the changing direction of the control command value, so that it corresponds to the accelerator operation in the normal control. It is also possible to realize a smooth command value correction that does not significantly change.

According to the invention of claim 3,
The same command value correction means: When the control command value is held near the predetermined opening position, the control command value is increased or decreased.
With this configuration, even when the throttle valve is being held near the predetermined opening position, the actual position of the throttle valve can be moved away from the vicinity of the predetermined opening position. Therefore, even when a control command is issued to keep the throttle valve near such a predetermined opening position, hunting of the throttle valve can be preferably avoided.

According to the invention of claim 4,
The command value correcting means: When the control command value is close to the predetermined opening position, the control value is corrected so as to reduce the control gain of the throttle valve by the throttle control means. With this configuration, for example, even when the throttle valve is controlled to open and close by crossing the vicinity of the predetermined opening position, the control gain is temporarily reduced when the control position reaches the vicinity of the predetermined opening position. The reaction of the feedback system is slowed down. Therefore, the hunting of the throttle valve is unlikely to occur, and the occurrence thereof can be preferably avoided.

According to the invention of claim 5,
When the control command value is near the predetermined opening position, a change in the accelerator operation amount is equal to or less than a predetermined value,
Feedback control of the throttle control means is prohibited and the throttle valve is held at that position.
With this configuration, even if the throttle valve is in the vicinity of the predetermined opening position, the feedback control is canceled unless the accelerator operation for acceleration or deceleration is performed, and the position of the throttle valve is also held at that position. Will be done. At least in such a control state, throttle valve hunting does not occur.

When the throttle driving means (c) is a DC motor which produces its driving torque in accordance with the duty ratio control of the pulse signal, this duty ratio control is canceled and a few mA (milliamperes) is maintained. By applying an electric current to the same DC motor, the throttle valve can be held at that position.

On the other hand, according to the invention of claim 6,
(J) command value correcting means: learning a predetermined opening position held by the holding means of the throttle valve, and moving the control command value to the vicinity of the predetermined opening position based on the learned position. To detect the transition of. With this configuration, even when the predetermined opening position of the throttle valve held by the holding means changes due to secular change of the holding means, mounting error of the throttle sensor, or the like, the predetermined opening position is The command value correction means ensures that the command value is always recognized correctly.

Then, the transition of the control command value to the vicinity of the predetermined opening position is detected on the basis of the position information that is always recognized correctly, so that the command value correction for avoiding the above-mentioned hunting is further performed. It will be executed accurately.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 shows a first embodiment of a throttle control device for an internal combustion engine according to the present invention.

The throttle control device according to this embodiment is applied as the throttle structure having the structure illustrated in FIG. 13 and FIG. 14 as a device capable of suitably preventing the hunting of the throttle valve. It is configured.

First, a schematic configuration of an internal combustion engine to which the throttle control device according to the embodiment is applied and peripheral devices thereof will be described with reference to FIG. In FIG. 1, an internal combustion engine 1 is configured as a V-type 6-cylinder 4-cycle engine, for example.

In this internal combustion engine 1, its intake passage 2
An air cleaner 3 is provided on the upstream side, and an air flow meter 4 that detects the amount of intake air to the engine 1 is provided on the downstream side of the air cleaner 3. The intake air amount detected by the air flow meter 4 is taken into the electronic control unit 20 described later as an air amount signal Qa.

A throttle valve 5 is provided in the intake passage 2 downstream of the air flow meter 4, and the amount of air supplied to the engine 1 is adjusted according to the opening / closing of the throttle valve 5. As described above, the throttle valve 5 and its peripheral structure have the structure shown in FIG. 8 above, and the outputs of the throttle sensor 16 and the accelerator sensor 17 provided as peripheral devices thereof are also respectively throttled. The opening degree signal VTA and the accelerator opening degree signal Ap are fetched by the electronic control unit 20 described later.

Further, the intake passage 2 is connected to each cylinder of the engine 1 via an intake manifold 6, and the air sucked from the intake passage 2 and metered by the throttle valve 5 is taken into the intake passage. It is distributed and supplied to each cylinder of the engine 1 through the manifold 6.

On the other hand, the intake manifold 6 is provided with injectors 7 which are fuel injection valves corresponding to the respective cylinders of the engine 1. The fuel injected and supplied through each of the injectors 7 is metered as described above,
It is mixed with intake air from the intake passage 2 that is distributed and supplied, and is supplied to each cylinder of the engine 1.

In each cylinder of the engine 1, the intake valve 8
The air-fuel mixture is introduced into the combustion chamber 9 with the opening and closing of the air-fuel mixture, and the introduced air-fuel mixture is combusted by the ignition of the spark plug 10 to push down the piston 11 and apply torque to the crankshaft 12. . The exhaust gas after combustion is discharged to the outside through the exhaust passage 14 as the exhaust valve 13 is opened and closed.

A crank angle sensor 15 for detecting the rotation angle of the crankshaft 12 is provided near the crankshaft 12. A pulse signal is output from the crank angle sensor 15 every 30 degrees in crank angle, and the output pulse signal is taken into the electronic control unit 20 as a rotation speed signal Ne of the engine 1.

The electronic control unit 20 controls the drive of the injector 7 on the basis of the air quantity signal Qa and the rotation speed signal Ne which are taken in, and at the same time, based on the throttle opening signal VTA and the accelerator opening signal Ap which are taken in. The device is configured to have, for example, a microcomputer that controls opening / closing of the throttle valve 5.

Next, the configuration of the electronic control unit 20 and its peripherals will be further described with reference to FIG. In the electronic control unit 20, the CPU 21 processes the air amount signal Qa, the rotation speed signal Ne, the throttle opening signal VTA, the accelerator opening signal Ap, and the like as required, and is required each time the internal combustion engine 1 is operated. Is a part for calculating the fuel injection amount, the opening of the throttle valve 55, etc.

The ROM 22 is a so-called program memory in which various programs for controlling the operation 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 the above-mentioned various arithmetic processes according to the programs stored in the ROM 22.

The RAM 23 is a so-called data memory in which the output data of the sensor and the arithmetic processing data by the CPU 21 are temporarily stored. Various flags described later are also set in the RAM 23.

The injector drive circuit 24 is a circuit for driving the injector 7 by forming a signal having a pulse width corresponding to the fuel injection amount calculated through the CPU 21 based on the air amount signal Qa and the rotation speed signal Ne. is there.
This causes the injector 7 to inject and supply the amount of fuel corresponding to the calculated fuel injection amount to each cylinder of the engine 1.

The electromagnetic clutch drive circuit 25 is turned on by the CPU 21 according to the operating state of the engine 1.
It is a circuit for switching control of ON (with connection) / OFF (without connection) of the electromagnetic clutch 18 based on an (ON) / OFF (OFF) command. When the electromagnetic clutch 18 is controlled to be ON, the throttle control by the normal DC motor 19 is enabled, and when the clutch 18 is controlled to be OFF, the accelerator operation is semi-mechanical for evacuation operation, for example. The state in which the corresponding throttle operation is possible is as described above with reference to FIG.

Further, the A / D conversion circuit 27 performs A (analog) / D (digital) conversion of the air amount signal Qa, the throttle opening signal VTA, the accelerator opening signal Ap, etc. which are taken in and outputs them to the CPU 21. The D / A conversion circuit 28 performs D / A conversion of the opening command value (throttle command value) TTP of the throttle valve 5 calculated by the CPU 21 and outputs it to the DC motor drive circuit 30. Circuit.

The DC motor drive circuit 30 comprises a PID control circuit 31, a PWM (pulse width modulation) circuit 32, and a driver 33, as shown in FIG.
This is a circuit for driving the motor 19.

Incidentally, in the DC motor drive circuit 30, the PID control circuit 31 determines the deviation based on the D / A converted throttle command value TTP and the throttle opening signal VTA output from the throttle sensor 16. This is a circuit for performing a proportional (P) / integral (I) / derivative (D) process to reduce the size and calculating a drive amount (control amount) of the DC motor 19. The calculated driving amount is converted into a corresponding duty ratio signal by the PWM circuit 32,
The converted duty ratio signal is applied to the DC motor 19 via the driver 33. That is, when the electromagnetic clutch 18 is ON, the throttle valve 5 is
Such a DC motor 1 through the DC motor drive circuit 30
By driving 9, the feedback control is performed to the opening degree commanded by the throttle command value TTP. The duty ratio signal converted by the PWM circuit 32 is also taken into the CPU 21 and its content is monitored.

2 to 6 specifically show a processing procedure and a processing mode regarding the control of the throttle valve 5 by the electronic control unit 20, which will be described below.
The throttle control mode as the throttle control device according to the embodiment will be described in more detail with reference to FIG.

First, the main routine of the throttle control shown in FIG. 2 will be described. The electronic control unit 20 starts execution of the main routine shown in FIG. 2 when the power source (not shown) is turned on. Note that this routine is repeatedly executed at a cycle of, for example, 4 ms (milliseconds).

In the main routine, the electronic control unit 20 first executes an initial check in step S100. In this initial check,
Checking for communication errors in each part of the electrical system
A mirror check or the like of the AM value is performed.

When the initial check is completed in this way,
Next, the electronic control unit 20 executes a primary check in step S200. In this primary check, the intermediate lever stopper 55 (see FIGS. 13 and 14) is mainly used.
The learning process for the position of (see) is performed. The details of the primary check will be specifically described later with reference to FIG.

The electronic control unit 20 that has completed this primary check then executes a flag process in step S300. In this flag processing, for example, flags indicating various control contents (control state) such as traction control, idle rotation control, constant speed traveling control, non-linear control (normal throttle control), etc., according to the operating state of the internal combustion engine 1. The process of setting in the RAM 23 is performed.

Thereafter, the electronic control unit 20 proceeds to step S
At 400, the opening command value TTP of the throttle valve 5 corresponding to the set control content (control state) flag is calculated. If necessary, that is, when the opening of the throttle valve 5 detected by the throttle sensor 16 indicates the vicinity of the learned position of the intermediate lever stopper 55, in step S500, the calculated opening command value TTP. Is also executed. Details of this correction processing will be specifically described later with reference to FIG.

In this way, the electronic control unit 20 which calculates or corrects the opening command value TTP of the throttle valve 5 in each case in step S600, the calculated opening command value TTP by D / A conversion circuit 28
To the DC motor drive circuit 30 via the.

After the internal combustion engine 1 is started, the above-mentioned steps S300-
Only the processing in S600 is repeatedly executed in the electronic control unit 20.

Next, the primary check executed as the process of step S200 of the main routine will be specifically described with reference to FIG. After completing the initial check, the electronic control unit 20 learns the position of the intermediate lever stopper 55 in the throttle mechanism (see FIGS. 13 and 14) as a primary check in the procedure shown in FIG. In the learning process, the key switch (not shown) is IG (ignition)-
It is executed by utilizing the period from ON to engine start.

Now, in this primary check routine, the electronic control unit 20 is in each of the steps S201, S202, and S203: IG-ON. -The electromagnetic clutch 18 is controlled to be OFF. -The starter is off (cranking has not started). The same primary check is started on the condition that is satisfied. If even one of these conditions is not satisfied, the counter for clocking is cleared (step S210), the routine is exited, and the process returns to the main routine. The electromagnetic clutch 18 is OF
As described above with reference to FIG. 13, the throttle valve 5 is held at the position of the intermediate lever stopper 55 by being controlled to F.

If all of these conditions are satisfied, the electronic control unit 20 determines in step S204 the output of the throttle sensor 16, that is, the throttle opening information VT.
Start reading A. Then, in step S205, it is determined whether or not the opening degree information VTA has changed, and if it is determined that the opening degree information VTA has changed, after clearing the clocking counter as in the above (step S210). ),
The process exits the routine and returns to the main routine. The opening information VTAi is the value of the opening information VTA read this time, and the opening information VTAi-1 is the value of the same opening information VTA read last time. The case where the throttle opening information VTA is changing means that the throttle valve 5 is not completely held at the position of the intermediate lever stopper 55, and in such a case, learning at the same position is stopped. It

If it is determined in step S205 that the throttle opening information VTA has not changed, the electronic control unit 20 further waits for the elapse of a predetermined time while increasing the count value of the time counting counter ( Steps S206 and S207), for example 32 ms
For example, when the predetermined time is reached, | VTA−VTSP | ≦ predetermined value 1 is satisfied (step S2
08), in step S209, the intermediate lever stopper 5
The learning value VTSP for the position 5 is updated based on the throttle opening information VTA at that time.

Here, the "predetermined value 1" is the upper and lower limit guard value of the learned value VTSP, and the read throttle opening information VTA and the learned value VT at that time.
The absolute value of the difference from SP is this predetermined value 1 (upper and lower limit guard values)
Even when it exceeds, learning of the position of the intermediate lever stopper 55 is stopped.

By learning about the position of the intermediate lever stopper 55 in this manner, the predetermined opening position held by the intermediate lever stopper 55 of the throttle valve 5 changes with age of the stopper 55 and the intermediate lever 53. Even when the throttle sensor 16 changes due to an attachment error or the like, the predetermined opening position is always correctly recognized by the electronic control unit 20. The updated learning value VTSP is stored in the RAM 23.
Alternatively, it is stored and saved in a backup RAM or the like (not shown).

Next, the correction process executed as the process of step S500 of the main routine will be specifically described with reference to FIG. The electronic control unit 20
When the opening command value TTP of the throttle valve 5 corresponding to the previous control content (control state) flag is calculated, the value of the calculated command value TTP is near the learned position of the intermediate lever stopper 55 through this correction process. It is checked whether the value is a value or not, and if the value is in the vicinity of the position of the intermediate lever stopper 55, this is corrected through the correction routine shown in FIG.

That is, in this correction routine, the electronic control unit 20 determines in step S511 that the calculated opening degree command value TTP of the throttle valve 5 is based on the comparison such as | TTP-VTSP | ≦ predetermined value 2. It is checked whether the value is a value near the learned position VTSP of the intermediate lever stopper 55. Here, the “predetermined value 2” is a judgment value for judging whether or not the range is in the vicinity.

As a result of the check, when it is determined that the value of the opening degree command value TTP is not near the position VTSP of the intermediate lever stopper 55, the electronic control unit 20 directly exits the correction routine and performs the above calculation. Opening command value TT
The value of P is output to the DC motor drive circuit 30 (step S600 in FIG. 2).

On the other hand, when it is determined that the value of the opening command value TTP is near the position VTSP of the intermediate lever stopper 55, the electronic control unit 20 further proceeds to step S512.
It is determined whether the opening degree command value TTP tends to decrease or increase. In FIG. 4, the value "TTPi" indicates the opening command value calculated this time, and the value "TTPi-1" indicates the opening command value calculated last time.

Then, in the electronic control unit 20, the same command value T
When it is determined that the TP tends to decrease, that is, the position is close to the position VTSP of the intermediate lever stopper 55 in the decreasing direction, in step S513, the command value TTP is set to, for example, TTP = VTSP-α. If it is determined that the command value TTP has a tendency to increase, that is, the value reaches the vicinity of the position VTSP of the intermediate lever stopper 55 in the increasing direction, it is determined in step S514. This command value TTP
In addition, for example, an increase correction such as TTP = VTSP + α is performed. This corrected opening command value T
The value of TP is also output to the DC motor drive circuit 30 as in the above (step S600 in FIG. 2).

FIG. 5 shows the throttle control mode by the same apparatus when such correction processing is not performed, and FIG. 6 shows the throttle control mode by the same apparatus when such correction processing is performed.

Next, with reference to FIG. 5 and FIG. 6 together, the throttle control mode by the device of the first embodiment will be described in more detail. 5 (a) and 6 (a), the DC motor 19
5 shows the behavior of the duty ratio signal given to FIG.
6B and 6B show the opening command value TTP of the throttle valve 5 calculated by the electronic control unit 20.
FIG. 5 (c) and FIG. 6 (c) show the transition of (target opening).
Shows the output transition of the throttle sensor 16 as an actual behavior of the throttle valve 5.

Now, when the throttle valve 5 is controlled near the intermediate lever stopper position (VTSP), as shown in FIG.
As shown in FIG. 5B, when the command value TTP is not subjected to any correction processing, the inversion of the motor torque is repeated as shown in FIG. Hunting of the throttle valve 5 as indicated by "valve hunting A" or "valve hunting B" in FIG. 5C will occur. Here, “valve hunting A” in FIG. 5C means that the throttle valve 5 is at the position of the intermediate lever stopper 55 (VTS).
P) is hunting that is likely to occur when opening and closing control is performed, and “valve hunting B” means that the throttle valve 5 is at the position of the intermediate lever stopper 55 (VTS).
This is hunting that tends to occur when holding control is performed near P).

However, in the equivalent control of the throttle valve 5, as indicated by the processing in the time domain A of FIG. 6B, the command value TTP is changed to the above-mentioned value as the device of the first embodiment. When the command value TTP increases and reaches near the position of the intermediate lever stopper 55, step correction is performed as "VTSP + α". When the command value TTP decreases and reaches the vicinity of the position of the intermediate lever stopper 55, the step correction is performed as "VTSP-α". In this manner, the command value TTP can be moved away from the same position (VTSP).

Therefore, at least when the throttle valve 5 is controlled to open and close by crossing the position (VTSP) of the intermediate lever stopper 55, the reversal of the motor torque is not repeated and the valve hunting caused by it is not repeated. Occurrence is also preferably avoided as shown in FIG.

As described above, according to the device of the first embodiment, (1) the throttle valve 5 is the intermediate lever stopper 5
Occurrence of hunting in the vicinity of the position 5 when the opening and closing control is performed by crossing the vicinity of the position 5 can be preferably avoided. (2) Moreover, since the opening degree of the throttle valve 5 is stepwise corrected in the same direction according to the changing direction of the control command value TTP, a smooth command value that does not greatly change the correspondence with the accelerator operation. The correction is also realized. (3) Further, since the position of the intermediate lever stopper 55 is learned each time, the same position can always be recognized correctly regardless of secular change or sensor mounting error. (4) And this learning information VT that is always correctly recognized
Since the transition of the control command value TTP to the vicinity of the position of the intermediate lever stopper 55 is detected based on SP, the command value correction for avoiding the above-mentioned hunting can be executed more accurately. And so on, many excellent effects can be obtained.

In the apparatus of the first embodiment, as described above, the command value TTP is step-corrected according to the transition direction thereof, but other command value correction processing is also possible. Various processing forms as exemplified as the following second to fourth embodiments can be adopted. Less than,
The main points of each of these embodiments will be sequentially described.

(Second Embodiment) In the second embodiment, the occurrence of "valve hunting B" shown in FIG. 5C is mainly prevented.

Specifically, in the apparatus according to the second embodiment, the electronic control unit 20 performs the correction process of step S500 in the main routine (FIG. 2) as follows.
The correction processing routine shown in FIG. 7 is executed.

That is, in this correction processing routine,
First, in step S521, the electronic control unit 20 sets the opening command value TTP of the throttle valve 5 to the intermediate lever stopper based on the comparison such as | TTP-VTSP | ≤ predetermined value 2 in the same manner as in the first embodiment. After checking whether or not the position of 55 is near the learning value VTSP, if it is determined that it is near the learning value VTSP, further,
In step S522, based on the comparison such as | TTPi-TTPi-1 | ≤ predetermined value 3, it is checked whether or not the command value TTP is held. Here, "TTP
“I” and “TTPi−1” are the “opening command value calculated this time” and the “previously calculated opening command value”, respectively, as described above, and the “predetermined value 3” is this command value. TTP
Is a determination value for determining whether or not is held.

When it is determined that the command value TTP is held near the position (VTSP) of the intermediate lever stopper 55, the electronic control unit 20 determines that the command value TTP is maintained.
It is determined whether TP is above (the valve opening side) or below (the valve closing side) the stopper position (VTSP) (step S523),
If it is on the upper side (valve opening side), an increase correction such as TTP = VTSP + β is performed in step S524, and if it is lower (the valve closing side), reduction correction such as TTP = VTSP-β is performed in step S525.

FIG. 8 exemplifies a throttle control mode based on such a correction process of the apparatus according to the second embodiment. In addition, in FIG. 8 as well, FIG.
8B shows the behavior of the duty ratio signal applied to the motor 19, and FIG. 8B shows the transition of the opening command value TTP (target opening) of the throttle valve 5 calculated through the electronic control unit 20. (C) shows the output transition of the throttle sensor 16 as an actual behavior of the throttle valve 5.

Here again, the throttle control equivalent to that in FIG. 5 is assumed. That is, the control command value TTP is in the vicinity of the position (VTSP) of the intermediate lever stopper 55. -There is no significant change and it is almost maintained. If no correction is made under such conditions, hunting of the throttle valve 5 as shown as "valve hunting B" in FIG. 5C will be caused.

However, in the same control of the throttle valve 5, as indicated by the processing in the time domain B of FIG. 8B, the command value TTP is set to the above-mentioned value as the device of the second embodiment. When the correction is performed: When the command value TTP is held near the position of the intermediate lever stopper 55 and above the same position (on the valve opening side), the step value is corrected as "VTSP + β". When the command value TTP is held near the position of the intermediate lever stopper 55 and below the same position (on the valve closing side), the step correction is performed as "VTSP-β". In this manner, the command value TTP can be moved away from the position.

Therefore, also in this case, the reversal of the motor torque is not repeated as shown in FIG. 8A, and the occurrence of valve hunting due to this is not generated.
It is preferably avoided as shown in (c).

(Third Embodiment) In the third embodiment, when the control command value TTP is close to the learning value VTSP for the position of the intermediate lever stopper 55, the feedback control of the throttle valve 5 is performed. Correct the gain so that it decreases.

Specifically, in the apparatus according to the third embodiment, the electronic control unit 20 performs the correction process of step S500 in the main routine (FIG. 2) as follows.
The correction processing routine shown in FIG. 9 is executed.

That is, in this correction processing routine,
First, in step S531, the electronic control unit 20 determines the opening degree command value TTP of the throttle valve 5 based on the comparison such as | TTP-VTSP | ≤ predetermined value 2 in the same manner as in the first or second embodiment. It is checked whether or not the value of the position of the intermediate lever stopper 55 is near the learned value VTSP.

The opening command value TTP is the learning value V
When it is determined that the TSP is in the vicinity, step S5
At 32, a change is made to lower the control gain. this is,
This can be dealt with by changing the proportional term (P term) constant of the PID control circuit 31 to a smaller value.

On the other hand, the same opening command value TTP is equal to the learned value VTS.
If it is determined that it is not near P, step S53.
As the processing of 3, normal feedback control based on normal control gain is performed.

FIG. 10 exemplifies a throttle control mode based on such correction processing of the device according to the third embodiment. For example, when the throttle valve 5 is controlled to open and close by crossing the vicinity of the position of the intermediate lever stopper 55 and the correction process is not performed, the normal control gain is set to the normal control gain in any time region. Based on this, feedback control with high responsiveness is performed. Then, at this time, in the area shown as the time area C in FIG. 10 where the position of the intermediate lever stopper 55 is crossed, hunting in the form shown by the broken line is likely to occur in the throttle valve 5.

However, in the same control of the throttle valve 5, as described above, when the correction for lowering the control gain related to the feedback control is performed near the position of the intermediate lever stopper 55 (learning value VTSP), the responsiveness thereof is reduced. Becomes dull, and in the mode shown by the solid line in FIG. 10,
The occurrence of valve hunting can be avoided.

As described above, even with the device according to the third embodiment, the hunting of the throttle valve 5 is unlikely to occur, and the occurrence thereof can be preferably avoided.

(Fourth Embodiment) In the fourth embodiment, when the control command value TTP is near the learning value VTSP for the position of the intermediate lever stopper 55, the change in the accelerator operation amount is equal to or less than a predetermined value. Under this condition, the feedback control of the throttle valve 5 is prohibited and the throttle valve 5 is held at the position.

Specifically, in the device according to the fifth embodiment, the electronic control unit 20 performs the correction process of step S500 in the main routine (FIG. 2) as follows.
The correction processing routine shown in FIG. 11 is executed.

That is, in this correction processing routine,
First, in step S541, the electronic control unit 20 sets the opening command value TTP of the throttle valve 5 to the intermediate lever stopper 55 based on the comparison such as | TTP-VTSP | ≤ predetermined value 2 in the same manner as in the previous embodiments. After checking whether the position is near the learning value VTSP, if it is determined that the position is near the learning value VTSP,
Similar to the second embodiment, in step S542, it is checked whether or not the command value TTP is held, based on the comparison such as | TTPi-TTPi-1 | ≤ predetermined value 3.

When it is determined that the command value TTP is held near the position (VTSP) of the intermediate lever stopper 55, the electronic control unit 20 determines ΔAp ≦ predetermined value 4 in the next step S543. Based on such comparison, it is checked whether or not the accelerator operation amount (accelerator opening) Ap has changed, and it is determined that it has not changed, step S544.
At this time, the feedback control of the throttle valve 5 is stopped, and a holding current of about several mA (milliamperes) is applied to the DC motor 19 to hold the throttle valve 5 at the position.

FIG. 12 exemplifies a throttle control mode based on such processing of the apparatus according to the fourth embodiment.
12 (a) shows the presence / absence of feedback control (F / B), FIG. 12 (b) shows the behavior of the duty ratio signal given to the DC motor 19, and FIG. FIG. 12C shows a transition of the opening command value TTP (target opening) of the throttle valve 5 calculated by the electronic control unit 20, and FIG. 12D shows the throttle as an actual behavior of the throttle valve 5. Sensor 16
12E shows the transition of the output, and FIG. 12E shows the transition of the accelerator operation amount (accelerator opening) Ap.

12 (c), 12 (e), and 12
As shown in (a), in the device according to the fourth embodiment, as described above, the control command value TTP is held near the position of the intermediate lever stopper 55 (learning value VTSP). thing. -The accelerator operation amount (accelerator opening) Ap has not changed. Based on the logical product condition of, the feedback control (F / B) is stopped while the same condition is satisfied. Then, while this feedback control (F / B) is stopped, a holding current of several mA is applied to the DC motor 19, and the throttle valve 5 is in the mode shown in FIG. Held in position.

As a result, the factor that causes hunting in the throttle valve 5 near the position of the intermediate lever stopper 55 is preferably eliminated. After that, if an accelerator operation for acceleration or deceleration is performed, the above conditions are canceled and the normal throttle control is resumed.

As described above, also in the device according to the fourth embodiment, hunting of the throttle valve 5 can be preferably avoided. By the way, in any of the first to fourth embodiments, the position of the intermediate lever stopper 55 is learned as the primary check, and the throttle valve 5 is learned based on the comparison with the learned value VTSP.
It is determined whether or not is near the position of the intermediate lever stopper 55.

Therefore, as described above, the same position can always be recognized correctly regardless of the secular change of those parts and the sensor mounting error, but such learning processing is essential for the same device. is not. That is, even if the position of the intermediate lever stopper 55 is simply stored as a constant, it is not possible to determine whether or not the throttle valve 5 is in the vicinity of the position of the intermediate lever stopper 55 according to the above-described embodiments. it can.

Further, in the apparatus according to the same embodiment, as shown in FIG.
Although the throttle mechanism having the structure illustrated in FIG. 3 and FIG. 14 is targeted for the throttle control, the first urging means for urging the throttle valve of the internal combustion engine in the valve closing direction. -Second urging means for urging the throttle valve in the opening direction. -Throttle drive means for opening and closing the throttle valve independently of the accelerator operation of the vehicle and against the biasing force of the first and second biasing means. -Clutch means for connecting and disconnecting the mechanical connection between the throttle drive means and the throttle valve. -Clutch control means for switching the connection / disconnection of the clutch means. .When the clutch means is controlled without engagement,
Holding means for holding the throttle valve at a predetermined opening position by balancing the biasing forces of the first and second biasing means in a predetermined manner. If at least
The configuration of the throttle control device according to the present invention can be applied in the same manner as in the above embodiment or in a manner similar to the above embodiment.

Further, the type of internal combustion engine to which the throttle control device is applied is arbitrary, and as long as it is an engine to which a so-called electronic throttle is applied and the intake amount thereof is adjusted, the above-mentioned V-type 6 Of course, the application is not limited depending on the engine type such as a cylinder 4-cycle engine.

[0112]

As described above, according to the present invention, in the throttle control device having the fail-safe function when control is impossible, hunting of the throttle valve or the like is suitably avoided, and so-called electronic control is performed. More reliable throttle control as a throttle device will be realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a throttle control device of the present invention.

FIG. 2 is a flowchart showing a throttle control main routine of the same apparatus.

FIG. 3 is a flowchart showing a primary check routine of the apparatus.

FIG. 4 is a flowchart showing a command value correction procedure according to the first embodiment.

FIG. 5 is a time chart showing a throttle valve control mode when a correction process is not performed.

FIG. 6 is a time chart showing a command value correction mode according to the first embodiment.

FIG. 7 is a flowchart showing a command value correction procedure according to the second embodiment.

FIG. 8 is a time chart showing a command value correction mode according to the second embodiment.

FIG. 9 is a flowchart showing a command value correction procedure according to the third embodiment.

FIG. 10 is a time chart showing a command value correction mode according to a third embodiment.

FIG. 11 is a flowchart showing a command value correction procedure according to the fourth embodiment.

FIG. 12 is a time chart showing a command value correction mode according to a fourth embodiment.

FIG. 13 is a schematic view schematically showing a throttle structure to which the same device is applied.

FIG. 14 is a schematic view schematically showing a throttle structure to which the same device is applied.

[Explanation of symbols]

1 ... Internal combustion engine, 2 ... Intake passage, 3 ... Air cleaner, 4 ...
Air flow meter, 5 ... Throttle valve, 6 ... Intake manifold, 7 ... Injector, 8 ... Intake valve, 9 ... Combustion chamber, 10 ... Spark plug, 11 ... Piston,
12 ... Crank shaft, 13 ... Exhaust valve, 14 ... Exhaust passage, 15 ... Crank angle sensor, 16 ... Throttle sensor, 17 ... Accelerator sensor, 18 ... Electromagnetic clutch, 1
9 ... DC motor, 20 ... Electronic control device, 21 ... CPU,
22 ... ROM, 23 ... RAM, 24 ... Injector drive circuit, 25 ... Electromagnetic clutch drive circuit, 27 ... A / D conversion circuit, 28 ... D / A conversion circuit, 30 ... DC motor drive circuit, 31 ... PID control circuit, 32 ... PWM (Pulse Width Modulation) circuit, 33 ... Driver, 51 ... Valve return spring, 52 ... Retraction traveling spring, 53 ... Intermediate lever, 54 ... Valve lever, 55 ... Intermediate lever stopper,
56 ... Valve fully closed stopper, 61 ... Accelerator return spring, 62 ... Accelerator lever, 63 ... Accelerator fully closed stopper.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F02D 11/10 F02D 11/10 Q F 29/00 29/00 H 45/00 340 45/00 340H

Claims (6)

[Claims] 1. A first urging means for urging a throttle valve of an internal combustion engine in a valve closing direction; a second urging means for urging the throttle valve in a valve opening direction; Throttle drive means for opening and closing independently of the accelerator operation of the vehicle and against the biasing force of the first and second biasing means, a throttle sensor for detecting the opening of the throttle valve, and the accelerator operation An accelerator sensor for detecting an amount, a clutch means for connecting and disconnecting the mechanical connection between the throttle drive means and the throttle valve, a clutch control means for switching the connection / disconnection by the clutch means, and the clutch means When the throttle valve is controlled to be open, the urging forces of the first and second urging means are balanced in a predetermined manner to open the throttle valve in a predetermined manner. Holding means for holding at a degree position, and throttle control means for feedback-controlling the opening / closing amount of the throttle valve through the throttle driving means based on the output of each sensor when the clutch means is controlled to be connected. Similarly, when the clutch means is controlled to be engaged and the throttle valve control command value by the throttle control means indicates the vicinity of a predetermined opening position held by the holding means of the throttle valve. ,
A throttle control device for an internal combustion engine, comprising: a command value correcting means for correcting the control command value. 2. The command value correcting means, when the control command value increases in the vicinity of the predetermined opening position,
2. The throttle control device for an internal combustion engine according to claim 1, wherein the control command value is increased and corrected, and when the control command value decreases in the vicinity of the predetermined opening position, the control command value is decreased and corrected. 3. The throttle control device for an internal combustion engine according to claim 1, wherein the command value correcting means corrects the control command value by increasing or decreasing when the control command value is held near the predetermined opening position. . 4. The internal combustion engine according to claim 1, wherein the command value correction means corrects the control gain of the throttle valve by the throttle control means to be lowered when the control command value is near the predetermined opening position. Engine throttle control. 5. The command value correction means controls the feedback control of the throttle control means under the condition that the change in the accelerator operation amount is a predetermined value or less when the control command value is near the predetermined opening position. The throttle control device for an internal combustion engine according to claim 1, wherein the throttle valve is prohibited and the throttle valve is held at the position. 6. The command value correction means learns a predetermined opening position held by the holding means of the throttle valve, and based on the learned position, approaches the control command value near the predetermined opening position. The throttle control device for an internal combustion engine according to any one of claims 1 to 5, which detects a transition of the above.