JPH11107785A - Throttle controller for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time required for setting a throttle valve to a proper opening position by stopping control after an opening of the throttle valve is set to a predetermined opening or less by means of drive of an actuator when a failure is caused in a throttle returning means and control based on a throttle controlling means is stopped. SOLUTION: By means of a CPU 21 in an ECU 20, a controlled variable for making an opening of a throttle valve 5 coincide with a target opening is computed. The computed control quantity is converted into control current, and a torque motor 19 is driven by means of a motor driving circuit 30 so as to control an opening of the throttle valve 5. When control of the throttle valve 5 is stopped, the opening of the throttle valve 5 is returned to a predetermined opening by means of a valve return spring. In this process, if a failure is caused in the valve return spring when control of the throttle valve 5 is stopped, the opening of the throttle valve 5 is reduced to the predetermined opening or less by means of drive of a torque motor 19, and then, control based on the CPU 21 is stopped.

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 Conventionally, an internal combustion engine called an "electronic throttle system" for controlling a throttle valve opening (hereinafter also referred to as "throttle opening") by driving a motor as an actuator in accordance with an accelerator operation amount or the like. Throttle control devices are known. In such a throttle control device, for example, a current is supplied to a motor in accordance with a signal from an accelerator opening sensor that detects an opening corresponding to the amount of depression of an accelerator pedal (hereinafter, referred to as “accelerator opening”), When the motor is driven, the throttle valve is opened and closed to control the amount of air supplied to the internal combustion engine.
At this time, a proportional / integral / differential control (Proportional Integral Differential Control) is performed on the motor so that the deviation between the signal from the throttle opening sensor for detecting the opening of the throttle valve and the signal from the accelerator opening sensor is eliminated.
trol; hereinafter, simply referred to as “PID control”).

[0003]

Here, when a failure occurs in the electronic throttle system, the motor is turned off, and the throttle valve is always closed by a specific valve return spring as a throttle return means. The opening is forcibly reduced to a predetermined opening or less. Thus, the engine speed of the internal combustion engine at the time of the system failure does not exceed the predetermined speed.

If the above-mentioned spring is damaged, the opening of the throttle valve will not be less than the predetermined opening even if the motor is turned off. Therefore, when the ignition switch is turned off with the throttle valve being larger than the predetermined opening, However, there has been a problem that the engine speed at the next start of the internal combustion engine becomes too high, and that it takes too much time to bring the throttle valve to an appropriate opening position thereafter.

Accordingly, the present invention has been made to solve such a problem, and can cope with a failure of the electronic throttle system due to a failure of the throttle return means for urging the throttle valve to the closing side. It is an object of the present invention to provide a throttle control device for an internal combustion engine that can prevent the engine speed at the time from being inadvertently excessively high and can shorten the time required for setting the throttle valve to an appropriate opening position.

[0006]

According to the throttle control device for an internal combustion engine of the first aspect, when the drive control of the throttle valve is stopped, the throttle return means for returning the opening of the throttle valve to a predetermined opening is provided. If a failure has occurred,
By driving the actuator before the stop, the throttle valve is set to a predetermined opening or less, so that the engine speed does not become too high at the next start of the internal combustion engine, and the throttle valve is set to an appropriate opening position. It doesn't take long. As a result, a highly reliable system can be constructed even if a failure occurs in the throttle return means in the electronic throttle system.

In the throttle control device for an internal combustion engine according to the second aspect, when the drive control of the throttle valve is stopped, if a failure occurs in the throttle return means, the opening of the throttle valve at that time may be any value. Is also forcibly returned to a predetermined intermediate position by driving the actuator. As a result, when the internal combustion engine is started next time, the engine speed becomes the engine speed corresponding to the intermediate position. Therefore, even if a failure occurs in the throttle return means in the electronic throttle system, it is possible to construct a system that is not inconvenient.

In the throttle control apparatus for an internal combustion engine according to the third aspect, in addition to the failure of the throttle return means, as a further failure, for example, when the throttle opening sensor fails, the actuator is driven to open the throttle valve to a predetermined opening. It is stopped after it is less than degree. As a result, when the throttle return means in the electronic throttle system fails, other failure determinations are also added,
A highly reliable system can be constructed even when a further failure occurs in addition to the throttle return means.

[0009]

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

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

In FIG. 1, an internal combustion engine 1 is configured as a V-type six-cylinder four-cycle engine. Internal combustion engine 1
An air cleaner 3 is provided on the upstream side of the intake passage 2 of
An air flow meter 4 for detecting an intake air amount (intake air amount) is provided downstream of the air cleaner 3. Further, a throttle valve 5 is provided downstream of the air flow meter 4 in the intake passage 2, and the opening degree of the throttle valve 5 (actual throttle) is controlled by the driving force of a torque motor 19 connected to a rotation shaft 5 a of the throttle valve 5. Is controlled, and the amount of intake air supplied to the internal combustion engine 1 is adjusted. The actual throttle opening of the throttle valve 5 is detected by a throttle opening sensor 16. Note that, even during idling, the actual throttle opening is controlled by the driving force of the torque motor 19, whereby the intake air amount GN is controlled, and feedback control is performed so 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 The CPU controls the opening / closing of the throttle valve 5 based on the 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, a throttle opening degree TA signal, an accelerator opening degree Ap signal, and the like, and is requested 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, a throttle opening of the throttle valve 5, 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 A / D conversion circuit 27 performs A / D (analog-digital) conversion of the read intake air amount GN signal, throttle opening degree TA signal, accelerator opening degree Ap signal, cooling water temperature THW signal, and the like. This is a circuit for outputting to the CPU 21. Further, the D / A conversion circuit 28 is
The command value TTP of the throttle opening of the throttle valve 5 by the torque motor 19 described later calculated by
/ A (digital-analog) conversion and output to the motor drive circuit 30. Motor drive circuit 30
Is a PID (proportional / integral / differential) control circuit 31, PWM
(Pulse Width Modulation) A command value TTP for driving a motor from the CPU 21 which is constituted by a circuit 32 and a driver 33.
This is a circuit for driving the torque motor 19 according to a signal.

Here, the command value T calculated by the CPU 21
The TP is converted into an analog value by the D / A conversion circuit 28 and input to the PID control circuit 31. PID control circuit 3
In P1, the PID calculation is executed to reduce the deviation based on the deviation between the command value TTP and the throttle opening TA signal from the throttle opening sensor 16, and the torque motor 19
Is calculated. In the PWM circuit 32, the control amount calculated by the PID control circuit 31 is input, and the control amount corresponds to a control current DUTY as a duty ratio signal.
And the driver 3 according to the control current DUTY
3, the torque motor 19 is driven, and the actual throttle opening TA signal detected by the throttle opening sensor 16 is adjusted so that it finally matches the throttle opening command value TTP (throttle target opening). You.

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
When the accelerator pedal 7 is not operated (accelerator OFF (off)), the accelerator lever 41 is held in a state of being in contact with the accelerator fully closed stopper 43 by the accelerator return springs 42a and 42b. During the operation of the internal combustion engine 1, the position of the accelerator lever 41 based on the operation amount of the accelerator pedal 17 is determined by the accelerator opening sensor 18 as the accelerator opening A.
It is detected as p.

On the other hand, a connection spring 5 is connected to a valve lever 44 connected to a rotation shaft 5a of the throttle valve 5.
2 is urged by the valve return spring 48 in the closing direction of the throttle valve 5 (downward in FIG. 2), and the motor O shown in FIG.
At the time of FF (when the power to the torque motor 19 is turned off), it is brought into contact with the intermediate stopper 49. At this time, the valve lever 44 is held at the intermediate stopper position where the intermediate lever 47 abuts via the connection spring 50, and the valve lever 44
Does not contact the throttle fully closed stopper 46.
The position of the intermediate stopper is determined by the motor OF as described later, although the throttle drive mechanism is normal but there is some other abnormality.
When there is a request of F, the vehicle can be evacuated, for example,
The engine speed is set to be slightly higher than the idle speed (throttle opening = about 3 °).

On the other hand, during the normal control (motor ON (ON)) shown in FIG. 2A, the torque motor 19 rotates forward or backward according to the operation amount of the accelerator pedal 17, and the throttle valve 5 is opened. The throttle opening is adjusted, and the throttle opening TA of the throttle valve 5 at that time is detected by the throttle opening sensor 16. At this time, when opening the throttle opening, the torque motor 19 is rotated forward, and as shown in FIG.
7, the throttle valve 5 is driven in the opening direction. Conversely, when closing the throttle opening, the throttle valve 5 is driven in the closing direction while the torque motor 19 is rotated in the reverse direction to lower the valve lever 44, and the throttle valve 5 is moved to the fully closed stopper position (throttle opening position). (Degree = 0.degree.), The valve lever 44 comes into contact with the throttle fully closed stopper 46, and further rotation is prevented.

Next, FIG. 4 shows a processing procedure for detecting a failure of the throttle opening sensor 16 in the CPU 21 in the ECU 20 used in the throttle control device for the internal combustion engine according to the first embodiment of the present invention. A description will be given based on the flowchart of FIG. This failure detection routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

In FIG. 4, first, in step S101, it is determined whether the difference between the two outputs from the throttle opening sensor 16 is equal to or greater than a predetermined value. Here, as shown in FIGS. 2 and 3, two throttle opening sensors 16 are arranged in parallel, and the respective outputs from both sensors are output from the ECU.
This is a double sensor system in which the opening degree of the throttle valve 5 is controlled by being input into the sensor 20. Step S101
If the determination condition is satisfied, that is, if the difference between the two outputs from the throttle opening sensor 16 is equal to or greater than a predetermined value, the process proceeds to step S102, and at least one of the two sensors of the throttle opening sensor 16 determines that the characteristic is abnormal. As a result, the flag XFAIL1 is changed from "0" to "1" by the initial setting. On the other hand, the determination condition of step S101 is not satisfied, that is, 2
If the difference between the two outputs is not equal to or greater than the predetermined value, it is determined that the throttle opening sensor 16 is not in the characteristic abnormal state and the process proceeds to step S1
02 is skipped.

Next, the routine proceeds to step S103, where it is determined whether the output from the throttle opening sensor 16 is equal to or greater than a predetermined value. When the determination condition in step S103 is satisfied, that is, when the output from the throttle opening sensor 16 is equal to or more than a predetermined value set in advance with respect to the reference voltage, the process proceeds to step S104. Here, when the throttle opening sensor 16 is normal, the throttle opening sensor 16
Does not exceed the predetermined value set in this way. Therefore, in step S104, it is determined that the throttle opening sensor 16 is in the disconnected state and the flag XF
AIL2 is changed from “0” by initial setting to “1”.
On the other hand, the determination condition of step S103 is not satisfied, that is,
If the output from the throttle opening sensor 16 is not greater than or equal to the predetermined value, the step S104 is skipped because the throttle opening sensor 16 is not in a disconnected state.

Next, the routine proceeds to step S105, where it is determined whether the output from the throttle opening sensor 16 is equal to or less than a predetermined value. If the determination condition of step S105 is satisfied, that is, if the output from the throttle opening sensor 16 is equal to or less than a predetermined value with respect to the ground, the process proceeds to step S106. Here, when the throttle opening sensor 16 is normal, the output does not fall below the predetermined value set in this manner. Therefore, in step S106, the flag XFAIL3 is changed from "0" to "1" by the initial setting, assuming that the throttle opening sensor 16 is in the short-circuit state, and the routine ends. On the other hand, when the determination condition of step S105 is not satisfied, that is, when the output from the throttle opening sensor 16 is not equal to or smaller than the predetermined value, it is determined that the throttle opening sensor 16 is not in the short-circuit state, step S106 is skipped, and this routine ends. .

FIG. 5 is a flowchart showing a procedure for detecting breakage of the valve return spring 48 in the CPU 21 in the ECU 20 used in the throttle control device for the internal combustion engine according to the first embodiment of the present invention. This will be described based on a flowchart. This breakage detection routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

Referring to FIG. 5, first, in step S201, it is determined whether an ignition switch (not shown) is turned on. When the determination condition of step S201 is satisfied, that is, when the electronic throttle system is activated, the process proceeds to step S202, and the throttle valve 5 is driven to a predetermined throttle opening θ1. In this embodiment, the throttle opening .theta.
Are set to the open side by a predetermined opening from the intermediate stopper position in contact with the intermediate stopper 49. Next, the process proceeds to step S203, where the torque motor 19 is turned off. Next, the routine proceeds to step S204, where the throttle opening .theta.2 of the throttle valve 5 after a predetermined time is detected by the throttle opening sensor 16.

Next, the process proceeds to step S205, and it is determined whether or not the throttle opening difference (θ1−θ2) based on the processing in steps S202 and S204 is equal to or larger than a predetermined value. At this time, if the valve return spring 48 biasing the throttle valve 5 to the closing side is not broken and normally acts on the throttle valve 5, the intermediate lever 47 abuts on the intermediate stopper 49. Until the stopper position is reached, the throttle valve 5 is returned to the closed side for a predetermined time. That is, when the valve return spring 48 is normal, the throttle opening difference (θ1−θ2) is equal to or larger than a predetermined value. If the determination condition of step S205 is not satisfied and the throttle opening difference (θ1−θ2) is smaller than a predetermined value, the process proceeds to step S205.
The routine proceeds to 206, where the flag XFAIL4 is changed from "0" to "1" by the initial setting assuming that the valve return spring 48 is in a broken state, and this routine ends.

On the other hand, when the determination condition of step S201 is not satisfied, that is, when the ignition switch is OFF, or the determination condition of step S205 is satisfied, that is,
When the valve return spring 48 is normal, this routine is terminated without doing anything.

Next, based on a flowchart of FIG. 6 showing a processing procedure of motor stop control in the CPU 21 in the ECU 20 used in the throttle control device for the internal combustion engine according to the first embodiment of the present invention. explain. This motor stop control routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

In FIG. 6, first, in step S301, it is determined whether there is an OFF request to the torque motor 19 or not. When the determination condition of step S301 is satisfied, that is, when the stop of the torque motor 19 is instructed for some reason, the process proceeds to step S302, and the flag XFAIL indicating whether the valve return spring 48 is normal or broken.
It is determined whether 4 is “1”. If the determination condition of step S302 is satisfied, that is, XFAIL4 = 1, and the valve return spring 48 is broken, the process proceeds to step S303. In step S303, the throttle valve 5 is driven to a preset intermediate stopper position (throttle opening near the opening during idling at which limp-home traveling is possible), and then the process proceeds to step S304.
The torque motor 19 is turned off, and this routine ends.

On the other hand, if the condition of step S302 is not satisfied, that is, if XFAIL4 = 0 and the valve return spring 48 is normal, step S303 is executed.
Is skipped, the process proceeds to step S304, the torque motor 19 is turned off, and the routine ends. When the determination condition of step S301 is not satisfied, that is, when there is no request for turning off the torque motor 19, the present routine is terminated without any operation.

As described above, the throttle control device for the internal combustion engine according to the present embodiment controls the control current DUTY to convert the opening of the throttle valve 5 to the target opening set based on various sensor signals. ECU to calculate quantity
A control amount calculating means achieved by the CPU 21 in 20;
The control amount DUTY calculated by the control amount calculating means is used to drive the torque motor 19 as an actuator by the control current DUTY, and the CPU 21 and the motor drive circuit 30 in the ECU 20 for controlling the opening degree of the throttle valve 5 are achieved. Throttle control means, a valve return spring 48 for returning the opening of the throttle valve 5 to a predetermined opening when the control by the throttle control means is stopped, and a throttle return means. When the control by the throttle control means is stopped after a failure occurs, the torque motor 19
Control stop means achieved by the CPU 21 in the ECU 20 which stops after the opening degree of the throttle valve 5 is reduced to the predetermined opening degree or less by the driving of.

That is, when the control of the electronic throttle system is stopped, if the valve return spring 48 for achieving the throttle return means has a failure, that is, if the damage has occurred, the throttle valve 5 is driven by the torque motor 19 before the stop. Is not more than a predetermined opening. For this reason, the engine speed does not become too high at the next start of the internal combustion engine, and since it does not take long time to bring the throttle valve 5 to the appropriate opening position, the valve return spring 48 in the electronic throttle system is damaged. Even if this occurs, the engine speed of the internal combustion engine is prevented from being carelessly increased, and a highly reliable system can be constructed.

In the throttle control device for an internal combustion engine according to the present embodiment, the control stop means achieved by the CPU 21 in the ECU 20 controls the opening of the throttle valve 5 to a predetermined intermediate position by driving the torque motor 19. It stops after the stop position. That is, when the control by the electronic throttle system is stopped, after the valve return spring 48 is damaged, no matter what the opening degree of the throttle valve 5 is at that time, the throttle valve 5 must be in the idling state as the predetermined intermediate position. It is forcibly returned to the intermediate stopper position set near the opening by driving the torque motor 19. As a result, when the internal combustion engine is started next time, the engine speed becomes close to the idling time, so that even if the valve return spring 48 in the electronic throttle system is damaged, a system that is not inconvenient can be constructed.

<Embodiment 2> FIG. 7 is a flowchart showing a processing procedure of a motor stop control in a CPU 21 in an ECU 20 used in a throttle control device for an internal combustion engine according to a second embodiment of the present invention. is there. This motor stop control routine is executed every predetermined time by the ECU.
20 is repeatedly executed by the CPU 21. Further, the configurations of the internal combustion engine to which the throttle control device for an internal combustion engine according to the present embodiment is applied and the peripheral devices thereof are the same as those in FIGS. 1 to 3 in the above-described first embodiment. Omitted. Further, FIG. 4 in the first embodiment described above.
The same applies to the failure detection routine of the throttle opening sensor 16 and the breakage detection routine of the valve return spring 48 in FIG.

In FIG. 7, first, it is determined in step S401 whether there is an OFF request to the torque motor 19. When the determination condition of step S401 is satisfied, that is, when the stop of the torque motor 19 is instructed for some reason, the process proceeds to step S402, and the flag XFAIL indicating whether the valve return spring 48 is normal or broken.
It is determined whether 4 is “1”. If the determination condition of step S402 is satisfied, that is, if XFAIL4 = 1 and the valve return spring 48 is broken, step S402
Move to 403. In step S403, the flag XF
It is determined whether there is a failure other than AIL4. Failures other than the breakage of the valve return spring 48 include XFAIL1 indicating the abnormal state of the characteristic of the throttle opening sensor 16, XFAIL2 indicating the disconnection state of the throttle opening sensor 16, and the throttle opening sensor 16 as described above.
XFAIL3 or the like indicating the short state of “1” is “1”.

If the condition of step S402 is satisfied, that is, if there is any abnormality in the throttle opening sensor 16 in addition to the breakage of the valve return spring 48, the process proceeds to step S404.
In step S404, a predetermined control current DUTY set in advance is output to the torque motor 19, and the throttle valve 5 is moved to a predetermined intermediate stopper position (throttle opening near the opening during idling at which limp-home traveling is possible). After the driving, the process proceeds to step S405, the torque motor 19 is turned off, and this routine ends. It is desirable that the control current DUTY in step S404 is equal to or less than the output for holding the intermediate stopper position.

On the other hand, when the determination condition of step S402 is not satisfied, that is, when XFAIL4 = 0 and the valve return spring 48 is normal, or when the determination condition of step S403 is not satisfied, that is, the valve return spring 48 is broken. If the throttle opening sensor 16 is normal, the throttle valve 5 is controlled to an appropriate opening position.
Step 404 is skipped, and the routine goes to step S405, where the torque motor 19 is turned off, and this routine ends. When the determination condition of step S401 is not satisfied, that is, when there is no OFF request to the torque motor 19, this routine ends without performing any operation.

As described above, in the throttle control device for an internal combustion engine according to the present embodiment, the control stop means achieved by the CPU 21 in the ECU 20 is not only capable of causing the failure of the valve return spring 48 as the throttle return means, that is, in addition to the damage. This is executed, for example, when a characteristic abnormality state, a disconnection state, or a short-circuit state of the throttle opening sensor 16 occurs as a further failure. That is, when the valve return spring 48 is damaged, the throttle opening sensor 16
If the above is also abnormal, the torque motor 19 is driven by the output of the predetermined control current DUTY, and the throttle valve 5 is stopped after the opening of the throttle valve 5 is reduced to the predetermined opening or less. As a result, when the valve return spring 48 is damaged in the electronic throttle system, a failure determination of the throttle opening sensor 16 and the like is added. System can be constructed.

In the above-described embodiment, the intermediate stopper position is set by contacting the intermediate lever 47 with the intermediate stopper 49. However, the present invention is not limited to this. However, the intermediate stopper position does not necessarily need to be set mechanically, and the intermediate stopper position may be set based on the throttle opening TA detected by the throttle opening sensor 16.

In the above embodiment, the torque motor 19 is used as the actuator. However, the present invention is not limited to this, and a DC motor or the like may be used. In particular, when the present invention is applied to a throttle control system using a torque motor, the effect that the accuracy and responsiveness to the throttle opening can be improved is remarkable.

[Brief description of the drawings]

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 a first example and a second example of an embodiment of the present invention is applied, and peripheral devices thereof.

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

FIG. 4 is a process of detecting a failure with respect to a throttle opening sensor in a CPU in an ECU used in a throttle control device for an internal combustion engine according to a first embodiment and a second embodiment of the present invention; It is a flowchart which shows a procedure.

FIG. 5 is a processing procedure for detecting breakage of a valve return spring in a CPU in an ECU used in a throttle control device for an internal combustion engine according to a first embodiment and a second embodiment of the present invention; It is a flowchart which shows.

FIG. 6 is a diagram showing E used in a throttle control device for an internal combustion engine according to a first embodiment of the present invention.
9 is a flowchart illustrating a processing procedure of motor stop control in a CPU in a CU.

FIG. 7 is a diagram showing E used in a throttle control device for an internal combustion engine according to a second embodiment of the present invention.
9 is a flowchart illustrating a processing procedure of motor stop control in a CPU in a CU.

[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) 30 motor drive circuit

Claims (3)

[Claims] 1. A control amount calculating means for calculating a control amount for making an opening of a throttle valve coincide with a target opening set based on various sensor signals, and the control amount calculated by the control amount calculating means. A throttle control unit that drives an actuator to control the opening of the throttle valve, and a throttle return unit that returns the opening of the throttle valve to a predetermined opening when control by the throttle control unit is stopped; When the control by the throttle control means is stopped after a failure has occurred in the throttle return means, control stop means for stopping the throttle valve after setting the opening of the throttle valve to the predetermined opening or less by driving the actuator. A throttle control device for an internal combustion engine, comprising: 2. The system according to claim 1, wherein the control stop means stops the throttle valve after driving the actuator to set the opening of the throttle valve at a predetermined intermediate position.
3. The throttle control device for an internal combustion engine according to claim 1. 3. The throttle for an internal combustion engine according to claim 1, wherein the control stop unit is executed when a further failure occurs in addition to the failure of the throttle return unit. Control device.