JP2003314336A - Throttle control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrict the generation of shock vibration due to hunting in an internal combustion engine when preventing excessive revolution of the internal combustion engine during traveling of a vehicle. <P>SOLUTION: When engine speed NE of the internal combustion engine exceeds the predetermined engine speed NE and the excessive revolving condition thereof is determined (time t01-time t02), independently of accelerator opening Ap from an accelerator opening sensor for detecting accelerator pedal operation quantity by a driver, throttle opening TA of a throttle valve, as operating condition of the internal combustion engine, is controlled to a target throttle opening TGTA set in response to a real gear position detected by a gear position sensor of a transmission. Excessive revolution of the internal combustion engine during travelling of the vehicle is prevented thereby, and the generation of shock vibration due to hunting in the internal combustion engine and deterioration of fuel consumption is restricted. <P>COPYRIGHT: (C)2004,JPO

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 prevents excessive rotation of the internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, it has been known that an engine speed of an internal combustion engine is controlled by a fuel cut when the engine speed exceeds a predetermined engine speed to prevent an overspeed of the engine. Here, the main purpose of preventing the excessive rotation of the internal combustion engine is to prevent damage to engine parts, prevent overheating of the exhaust system, and reduce fuel consumption.

By the way, the rotational speed control by the fuel cut for preventing over-rotation at the time of high speed rotation of the internal combustion engine is
Generally, this is performed by stopping the fuel injection from the injector (fuel injection valve) when the engine speed exceeds a predetermined speed. In such rotation speed control by fuel cut at high speed rotation, since the internal combustion engine continues to rotate at high speed in a hunted state, shock vibration and deterioration of fuel consumption due to this hunting occur.

As a prior art document for dealing with this, the one disclosed in Japanese Utility Model Publication No. 6-6211 is known. In this system, in addition to the throttle valve that opens and closes in accordance with the accelerator pedal depression amount, a sub-throttle valve that is opened and closed by an actuator in response to a control signal from the electronic control unit is provided separately from the accelerator pedal depression amount. . Then, when the predetermined operating state is reached, the sub-throttle valve is gradually controlled to the close side, whereby overspeed of the internal combustion engine is prevented without performing rotation speed control by fuel cut to the internal combustion engine, It is said that shock vibration due to hunting is prevented.

[0005]

However, in the above-mentioned one, the internal combustion engine is in a no-load state (idle state) while the vehicle is stopped.
In the above, only the case where the engine rotation speed is equal to or higher than a predetermined value and the engine temperature is equal to or higher than a predetermined value in a racing state is considered. That is, when the rotation speed control by the fuel cut to the internal combustion engine is carried out at the high speed rotation while the vehicle is traveling, the hunting of the internal combustion engine similar to that described above is not taken into consideration when preventing the excessive rotation of the internal combustion engine during the traveling of the vehicle. There was a problem that shock vibration occurred due to.

Therefore, the present invention has been made to solve the above problems, and an internal combustion engine capable of suppressing shock vibration due to hunting of the internal combustion engine when the internal combustion engine is prevented from over-rotating while the vehicle is traveling. It is an object to provide a throttle control device.

[0007]

According to another aspect of the present invention, there is provided a throttle control device for an internal combustion engine, wherein the engine speed of the internal combustion engine detected by the throttle speed detecting means by the throttle control means is higher than a predetermined rotational speed and is excessively high. When it is determined that the state, regardless of the size of the accelerator opening according to the accelerator pedal depression amount detected by the accelerator opening detection means,
That is, the throttle opening of the throttle valve is controlled to a predetermined target throttle opening set according to the operating state of the internal combustion engine, regardless of the control amount for matching the throttle opening set by the control amount calculation means. To be done. This allows
Over-rotation of the internal combustion engine is prevented while the vehicle is traveling, and shock vibration and deterioration of fuel consumption due to hunting of the internal combustion engine at this time are suppressed.

In the throttle control means in the throttle control device for the internal combustion engine according to the second aspect, when the engine speed of the internal combustion engine becomes higher than the predetermined speed and it is determined that the engine is in the over-rotation state, regardless of the accelerator opening degree. Instead, the rotational speed control by fuel cut for the internal combustion engine is also used to control the throttle opening of the throttle valve to a predetermined target throttle opening set according to the operating state of the internal combustion engine. As a result, even when the engine rotation speed exceeds the predetermined rotation speed and overshoots significantly, the effect of smoothing the behavior until reaching the predetermined rotation speed can be obtained.

According to another aspect of the throttle control device for an internal combustion engine, the target throttle opening degree is set according to at least one of the gear position of the transmission and the load of the internal combustion engine. That is, when the engine speed of the internal combustion engine becomes higher than the predetermined speed and the engine is determined to be in the overspeed state, at least one of the gear position at that time as the operating state of the internal combustion engine and the load of the internal combustion engine is determined. The target throttle opening is set to the target throttle opening. As a result, over-rotation of the internal combustion engine while the vehicle is traveling is prevented, and shock vibration and deterioration of fuel consumption due to hunting of the internal combustion engine at this time are suppressed.

According to another aspect of the throttle control device for an internal combustion engine, the target throttle opening degree corresponds to at least one of atmospheric pressure, intake air temperature, cooling water temperature, oil temperature of lubricating oil of the internal combustion engine, and oil temperature of the transmission. Will be corrected. In other words, when the engine speed of the internal combustion engine becomes higher than the predetermined speed and it is determined that the engine is in the over-rotation state, the target throttle opening set according to the operating state of the internal combustion engine becomes temperature,
It is corrected according to at least one of the cooling water temperature, the oil temperature of the lubricating oil of the internal combustion engine, and the oil temperature of the transmission. As a result, over-rotation of the internal combustion engine while the vehicle is traveling is prevented, and shock vibration and deterioration of fuel consumption due to hunting of the internal combustion engine at this time are suppressed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on Examples.

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

In FIG. 1, an internal combustion engine 1 is constructed, for example, as a 4-cylinder 4-cycle spark ignition type, and its intake air serves as an actuator that constitutes an air cleaner 2, an intake passage 3, and a well-known electronic throttle mechanism from the upstream side. D
The injector (fuel injection valve) in the intake manifold 7 passes through the throttle valve 5, the surge tank 6 and the intake manifold 7 which are driven to open and close by the C motor 4.
It is mixed with the fuel injected from No. 8 and distributed and supplied to each cylinder as an air-fuel mixture having a predetermined air-fuel ratio. In addition, an igniter 10 directly connected to an ignition plug 9 provided in each cylinder of the internal combustion engine 1 includes an ECU (Electronic Control U) described later.
(nit: electronic control unit) 30 is input, and the air-fuel mixture in each cylinder is burned at a predetermined timing by spark ignition of the spark plug 9.

Then, the exhaust gas after combustion passes through the exhaust manifold 11 and the exhaust passage 12, and the exhaust passage 1
CO, HC, NOx, etc., which are harmful components, are purified by the three-way catalyst 13 provided in No. 2 and carrying a catalyst component such as platinum and rhodium and an additive such as cerium and lanthanum, and discharged into the atmosphere. Exhaust passage 12 provided with this three-way catalyst 13
An air-fuel ratio (A / F) sensor 14 is provided on the upstream side of
The air-fuel ratio sensor 14 detects a linear voltage signal VOX1 corresponding to the air-fuel ratio λ of the exhaust gas discharged from the internal combustion engine 1.

An intake air temperature sensor 21 is provided on the downstream side of the air cleaner 2. The intake air temperature sensor 21 detects the intake air temperature THA [° C.] passing through the air cleaner 2. Further, an air flow meter 22 is provided in the intake passage 3 on the downstream side of the air cleaner 2, and the intake air amount GN [g / re
v] is detected. The throttle valve 5 is provided with a throttle opening sensor 23. The throttle opening sensor 23 detects an analog signal corresponding to the throttle opening TA [°] and the throttle valve 5 is fully closed. It is detected by an ON / OFF signal from an idle switch (not shown).

Further, the surge tank 6 has an intake pressure sensor 2
4 is provided, and the intake pressure PM is detected by the intake pressure sensor 24.
[KPa] is detected. A water temperature sensor 25 is provided in the cylinder block of the internal combustion engine 1, and the water temperature sensor 25 detects the cooling water temperature THW [° C] of the internal combustion engine 1. In addition, the crankshaft (not shown) of the internal combustion engine 1 is provided with a crank angle sensor 26, and the crank angle sensor 26 allows the engine rotation speed NE [r
pm] is detected. Further, the accelerator opening sensor 27 corresponds to the accelerator opening amount Ap [°] corresponding to the driver's accelerator pedal depression amount, and the vehicle speed sensor 28 corresponds to the vehicle speed SPD [km / km].
h], the gear position GP of a transmission (not shown) mounted on the vehicle is detected by the gear position sensor 29.

ECU 3 for controlling the operating state of internal combustion engine 1
Reference numeral 0 denotes a CPU 31 as a central processing unit that executes various known arithmetic processes, a ROM 32 that stores a control program and a control map, a RAM 33 that stores various data, and B /
It is configured as a logical operation circuit including a U (backup) RAM 34, an input / output circuit 35, a bus line 36 connecting them, and the like.

The air-fuel ratio of the air-fuel mixture based on the exhaust gas is determined by the voltage signal VOX1 from the air-fuel ratio sensor 14 input to the ECU 30 via the input / output circuit 35.
Further, the intake air temperature THW from the intake air temperature sensor 21 and the air flow meter 22 are input to the ECU 30 via the input / output circuit 35.
Intake air amount GN from the throttle opening sensor 23, throttle opening TA from the throttle opening sensor 23, intake pressure PM from the intake pressure sensor 24, cooling water temperature THW from the water temperature sensor 25, engine speed NE from the crank angle sensor 26, accelerator Accelerator opening Ap from the opening sensor 27, vehicle speed SPD from the vehicle speed sensor 28, gear position GP from the gear position sensor 29
Various sensor signals such as are input, and based on them, DC
Control amount DV for motor 4, fuel injection amount TAU for injector 8, ignition timing I for igniter 10
g and the like are calculated, and control signals are output to the DC motor 4, the injector 8, the igniter 10 and the like via the input / output circuit 35.

Next, E used in the throttle control device for the internal combustion engine according to an example of the embodiment of the present invention.
A description will be given with reference to FIG. 3 based on the flowchart of FIG. 2 showing the processing procedure of the target throttle opening calculation in the throttle control of the CPU 31 in the CU 30. Here, FIG.
2 is a time chart showing transition states of various sensor signals and various control amounts corresponding to the processing of FIG. It should be noted that this target throttle opening calculation routine is executed by the CPU 3 at predetermined time intervals.
1 is repeatedly executed.

In FIG. 2, in step S101, it is determined whether the engine rotation speed NE [rpm] of the internal combustion engine 1 is equal to or higher than a preset predetermined rotation speed NEth [rpm]. When the determination condition of step S101 is satisfied, that is, when the engine rotation speed NE at this time is higher than the predetermined rotation speed NEth (time t01 to time t02 shown in FIG. 3), step S101 is performed.
The routine proceeds to 102, where the target throttle opening degree TGTA [°] corresponding to the gear position GP is calculated by the table using the gear position GP as a parameter, and this routine ends.

Incidentally, as shown in FIG. 3, the predetermined rotational speed NEth is set so that the setting of the target throttle opening TGTA is not canceled by the behavior until the engine rotational speed NE reaches the predetermined rotational speed NEth. Hysteresis Δ
NEth is provided. On the other hand, the determination condition of step S101 is not satisfied, that is, the engine speed NE at this time is
Is lower than the predetermined rotation speed NEth (before time t01 or after time t02 shown in FIG. 3), this routine is ended without doing anything.

According to the above-described routine, from time t01 to time t02 shown in FIG. 3 in which the engine speed NE of the internal combustion engine 1 becomes equal to or higher than the predetermined speed NEth, the accelerator opening degree according to the accelerator pedal depression amount of the driver. The throttle opening TA is set to the target throttle opening TGTA according to the current gear position GP regardless of the magnitude of Ap. The timing for releasing the setting of the target throttle opening TGTA with respect to the throttle opening TA is such that the accelerator opening Ap corresponding to the accelerator pedal depression amount of the driver becomes smaller and the engine rotation speed NE becomes equal to or higher than the predetermined rotation speed NEth. When the accelerator opening is lower than the accelerator opening (time t01 shown in FIG. 3) (see FIG. 3).
Is time t02). As a result, it is possible to prevent the internal combustion engine 1 from excessively rotating while the vehicle is traveling, and it is possible to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

As described above, the throttle control device for the internal combustion engine according to the present embodiment has the crank angle sensor 26 as the rotational speed detecting means for detecting the engine rotational speed NE of the internal combustion engine 1.
And an accelerator opening sensor 27 as an accelerator opening detecting means for detecting an accelerator opening Ap corresponding to a depression amount of an accelerator pedal (not shown), and a throttle opening TA of a throttle valve 5 based on the accelerator opening Ap. The control amount calculation means achieved by the ECU 30 for calculating the control amount DV for matching the set throttle opening and the DC motor 4 as an actuator based on the control amount DV calculated by the control amount calculation means. A throttle control means that is driven by the ECU 30 for controlling the throttle opening TA of the throttle valve 5; the throttle control means is configured to operate the accelerator when the engine speed NE becomes equal to or higher than a predetermined speed NEth. Regardless of the size of the opening Ap, the throttle opening TA of the throttle valve 5 is set to the operating condition of the internal combustion engine 1. And controls the predetermined target throttle opening TGTA set according to. Further, the throttle control device for the internal combustion engine of the present embodiment sets the target throttle opening degree TGTA according to the gear position GP of the transmission (not shown).

That is, when the engine rotational speed NE of the internal combustion engine 1 becomes higher than the predetermined rotational speed NEth and it is determined that the engine is in the over-rotation state, the accelerator opening sensor 27 detects the accelerator pedal depression amount of the driver. The throttle opening T of the throttle valve 5 regardless of the opening Ap.
As the operating state of the internal combustion engine 1, A is controlled to the target throttle opening degree TGTA set according to the current gear position GP from the gear position sensor 29 of the transmission. This allows
It is possible to prevent over-rotation of the internal combustion engine 1 while the vehicle is traveling, and to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

Next, E used in the throttle control device for an internal combustion engine according to an example of the embodiment of the present invention.
Based on the flowchart of FIG. 4 showing the first modified example of the processing procedure of the target throttle opening degree calculation in the throttle control of the CPU 31 in the CU 30, it will be described with reference to the time chart of FIG. 3 described above. The target throttle opening calculation routine is repeatedly executed by the CPU 31 every predetermined time.

In FIG. 4, in step S201, it is determined whether the engine rotation speed NE [rpm] of the internal combustion engine 1 is equal to or higher than a preset predetermined rotation speed NEth [rpm]. When the determination condition of step S201 is satisfied, that is, when the engine rotation speed NE at this time is higher than the predetermined rotation speed NEth (time t01 to time t02 shown in FIG. 3), step S201 is performed.
202, and the intake air amount GN [g / r as a load]
ev] is used as a parameter to calculate the target throttle opening degree TGTA [°] corresponding to the intake air amount GN, and this routine is ended. In addition, step S in FIG.
In the table used in 202, the target throttle opening TGTA for the intermediate value of the intake air amount GN is calculated by interpolation calculation. On the other hand, when the determination condition of step S201 is not satisfied, that is, when the engine rotation speed NE at this time is as low as less than the predetermined rotation speed NEth (time t shown in FIG.
Before 01 or after time t02), this routine ends without doing anything.

According to the above-described routine, from time t01 to time t02 shown in FIG. 3 in which the engine speed NE of the internal combustion engine 1 becomes equal to or higher than the predetermined speed NEth, the accelerator opening degree according to the accelerator pedal depression amount of the driver. The throttle opening TA is set to the target throttle opening TGTA according to the current intake air amount GN regardless of the magnitude of Ap. This allows
It is possible to prevent over-rotation of the internal combustion engine 1 while the vehicle is traveling, and to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

As described above, the throttle control device for the internal combustion engine of the present modification sets the target throttle opening degree TGTA in accordance with the intake air amount GN as the load of the internal combustion engine 1. That is, when the engine rotation speed NE of the internal combustion engine 1 becomes higher than the predetermined rotation speed NEth and it is determined that the engine is in the over-rotation state, the target throttle set as the operating state of the internal combustion engine 1 according to the current intake air amount GN. The opening is controlled to TGTA. As a result, it is possible to prevent the internal combustion engine 1 from excessively rotating while the vehicle is traveling, and it is possible to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

Next, E used in the throttle control device for an internal combustion engine according to an example of the embodiment of the present invention.
Based on the flowchart of FIG. 5 showing a second modification of the processing procedure of the target throttle opening degree calculation in the throttle control of the CPU 31 in the CU 30, description will be given with reference to the above-mentioned time chart of FIG. The target throttle opening calculation routine is repeatedly executed by the CPU 31 every predetermined time.

In FIG. 5, in step S301, it is determined whether the engine rotation speed NE [rpm] of the internal combustion engine 1 is equal to or higher than a preset predetermined rotation speed NEth [rpm]. If the determination condition of step S301 is satisfied, that is, if the engine rotation speed NE at this time is higher than the predetermined rotation speed NEth (time t01 to time t02 shown in FIG. 3), step S301 is performed.
302, the target throttle opening degree TGTA [°] corresponding to the gear position GP and the intake air amount GN is calculated by a table having the gear position GP and the intake air amount GN [g / rev] as a parameter as parameters. This routine ends. In the table shown in step S302 of FIG. 5, the target throttle opening TGTA for the intermediate value of the intake air amount GN is calculated by interpolation calculation. on the other hand,
If the determination condition of step S301 is not satisfied, that is, if the engine rotation speed NE at this time is as low as less than the predetermined rotation speed NEth (before time t01 or after time t02 shown in FIG. 3), the operation is performed without doing anything. Exit the routine.

According to the above-mentioned routine, from time t01 to time t02 shown in FIG. 3 in which the engine speed NE of the internal combustion engine 1 becomes equal to or higher than the predetermined speed NEth, the accelerator opening degree according to the accelerator pedal depression amount of the driver. The throttle opening TA is set to the target throttle opening TGTA according to the current gear position GP and the current intake air amount GN regardless of the magnitude of Ap. Thereby, the internal combustion engine 1 while the vehicle is traveling
Can be prevented, and at the same time, shock vibration and deterioration of fuel consumption due to hunting of the internal combustion engine 1 at this time can be suppressed.

As described above, in the throttle control device for the internal combustion engine of the present modification, the target throttle opening TGTA is set according to the gear position GP of the transmission (not shown) and the intake air amount GN as the load of the internal combustion engine 1. It is something to set. That is, the engine rotation speed NE of the internal combustion engine 1 is equal to the predetermined rotation speed NE.
If the engine speed becomes higher than th and is determined to be an over-rotation state, the target throttle opening degree T set as the operating state of the internal combustion engine 1 according to the current gear position GP and the current intake air amount GN is set.
Controlled by GTA. As a result, it is possible to prevent the internal combustion engine 1 from excessively rotating while the vehicle is traveling, and it is possible to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

Next, E used in the throttle control device for an internal combustion engine according to an example of the embodiment of the present invention.
Based on the flowchart of FIG. 6 showing the third modification of the processing procedure of the target throttle opening degree calculation in the throttle control of the CPU 31 in the CU 30, description will be made with reference to the time chart of FIG. 3 described above. The target throttle opening calculation routine is repeatedly executed by the CPU 31 every predetermined time.

In FIG. 6, in step S401, it is determined whether the engine rotation speed NE [rpm] of the internal combustion engine 1 is equal to or higher than a preset predetermined rotation speed NEth [rpm]. When the determination condition of step S401 is satisfied, that is, when the engine rotation speed NE at this time is higher than the predetermined rotation speed NEth (time t01 to time t02 shown in FIG. 3), step S401 is performed.
The routine proceeds to 402, and the temporary target throttle opening degree TTGTA [°] corresponding to the gear position GP is calculated by the table using the gear position GP as a parameter. Next in step S40
3, the target throttle opening correction amount CT corresponding to the atmospheric pressure PA is obtained by a table using the atmospheric pressure PA [kPa] detected by an atmospheric pressure sensor (not shown) as a parameter.
GTA is calculated. In the table shown in step S403 of FIG. 6, the target throttle opening correction amount CTGTA for the intermediate value of the atmospheric pressure PA is calculated by interpolation calculation.

Next, the process proceeds to step S404, and the temporary target throttle opening degree TTGT calculated in step S402.
A is multiplied by the target throttle opening correction amount CTGTA calculated in step S403 to obtain the target throttle opening TGT.
A [°] is calculated, and this routine ends. On the other hand, if the determination condition of step S401 is not satisfied, that is, if the engine rotation speed NE at this time is as low as less than the predetermined rotation speed NEth (before time t01 or after time t02 shown in FIG. 3), do nothing. Without this routine, it ends.

According to the above-mentioned routine, from time t01 to time t02 shown in FIG. 3 in which the engine speed NE of the internal combustion engine 1 becomes equal to or higher than the predetermined speed NEth, the accelerator opening degree according to the accelerator pedal depression amount of the driver. Regardless of the magnitude of Ap, the throttle opening TA is the current atmospheric pressure P relative to the provisional target throttle opening TTGTA corresponding to the current gear position GP.
The target throttle opening correction amount CGTTA corresponding to A is set to the target throttle opening TGTA. As a result, it is possible to prevent the internal combustion engine 1 from excessively rotating while the vehicle is traveling, and it is possible to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

As described above, the throttle control device for the internal combustion engine of this modification sets the temporary target throttle opening degree TTGTA in accordance with the gear position GP of the transmission (not shown) when setting the target throttle opening degree TGTA. Then, the temporary target throttle opening degree TTGTA is corrected by the target throttle opening degree correction amount CTGTA according to the atmospheric pressure PA. That is, the engine rotation speed NE of the internal combustion engine 1 is equal to the predetermined rotation speed NE.
When the engine speed becomes higher than th and is determined to be the over-rotation state, the temporary target throttle opening degree TTGTA set according to the current gear position GP as the operating state of the internal combustion engine 1 is the target according to the current atmospheric pressure PA. The target throttle opening correction amount CGTTA is corrected by the throttle opening correction amount CTGTA. Thereby, the internal combustion engine 1 while the vehicle is traveling
Can be prevented, and at the same time, shock vibration and deterioration of fuel consumption due to hunting of the internal combustion engine 1 at this time can be suppressed.

Next, in addition to the throttle control for preventing the excessive rotation of the internal combustion engine 1 according to the above-mentioned embodiment and the modification, the case where the rotational speed control by the fuel cut to the internal combustion engine 1 is executed together is executed. This will be described with reference to the time chart of.

From time t11 to time t16 shown in FIG. 7, the engine rotation speed NE of the internal combustion engine 1 becomes equal to or higher than the predetermined rotation speed NEth1. Therefore, the accelerator opening Ap corresponding to the accelerator pedal depression amount of the driver becomes large. Regardless of throttle opening T
A is set to the target throttle opening TGTA according to the current gear position GP, the current intake air amount GN, and the like. Therefore, the throttle control similar to that of the above-described embodiment and modification is executed.

Further, the engine rotation speed NE of the internal combustion engine 1 exceeds the predetermined rotation speed NEth1, and as shown after time t11 shown in FIG.
When th2 is exceeded, the fuel cut execution flag becomes "ON". When the fuel cut execution flag is set to “ON”, the well-known internal combustion engine 1 is subjected to the fuel cut rotation speed control. That is, from time t12 shown in FIG.
During the period from time t13 and time t14 to time t15, in addition to the setting of the target throttle opening TGTA of the throttle opening TA by the throttle control for the internal combustion engine 1, the rotational speed control by the fuel cut for the internal combustion engine 1 is also used. Fuel injection from the injector 8 to 1 is stopped.

The fuel cut execution flag is "OFF."
(OFF) ”is the timing when the engine speed NE falls below the hysteresis amount ΔNEth2 provided for the predetermined engine speed NEth2 (time t13 shown in FIG. 7).
Or time t15). As a result, it is possible to prevent the internal combustion engine 1 from excessively rotating while the vehicle is traveling, and it is possible to suppress shock vibration and deterioration of fuel efficiency due to hunting of the internal combustion engine 1 at this time.

The throttle control means achieved by the ECU 30 of the throttle control device for such an internal combustion engine determines that the engine speed NE is higher than the predetermined speed NEth1 and higher than the predetermined speed NEth2 and is in the overspeed state. Then, regardless of the magnitude of the accelerator opening Ap, the throttle opening TA of the throttle valve 5 is set to a predetermined value that is set according to the operating state of the internal combustion engine 1 by using the rotational speed control by fuel cut for the internal combustion engine 1 together. The target throttle opening TGTA is controlled, and in addition to the operation and effect similar to those of the above-described embodiment and modification, the engine rotation speed NE exceeds the predetermined rotation speed NEth1 and greatly overshoots. Can be smoothed in a short time until reaching the predetermined rotation speed NEth1.

[Brief description of 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 an embodiment of the present invention is applied and peripheral equipment thereof.

FIG. 2 is an EC used in a throttle control device for an internal combustion engine according to an example of an embodiment of the present invention.
6 is a flowchart showing a processing procedure for calculating a target throttle opening degree in throttle control of a CPU in U.

FIG. 3 is a time chart showing transition states of various sensor signals and various control amounts corresponding to the processing of FIG.

FIG. 4 is a flowchart showing a first modification of the processing procedure for calculating the target throttle opening degree in FIG.

FIG. 5 is a flowchart showing a second modification of the processing procedure of the target throttle opening degree calculation of FIG.

FIG. 6 is a flowchart showing a third modification of the processing procedure for calculating the target throttle opening degree in FIG.

FIG. 7 is an EC used in a throttle control device for an internal combustion engine according to an example of an embodiment of the present invention.
6 is a time chart showing transition states of various sensor signals, various control amounts, etc. corresponding to a case where a rotational speed control by fuel cut for an internal combustion engine is executed in addition to throttle control in a CPU in U.

[Explanation of symbols]

1 Internal combustion engine 4 DC motor (actuator) 5 Throttle valve 26 Crank angle sensor (rotational speed detection means) 27 Accelerator opening sensor (accelerator opening detecting means) 29 Gear position sensor 30 ECU (electronic control unit)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F02D 41/04 F02D 41/04 310G F term (reference) 3G065 CA02 CA14 DA05 EA11 GA01 GA05 GA09 GA10 GA27 GA31 GA41 GA46 3G093 AA05 BA06 CA05 CA11 DA03 DA05 DA06 DA07 DA09 EA05 EA09 EC02 FB02 3G301 JA04 JA06 JA34 JA37 KA25 LA03 LB02 MA24 NA08 NC02 NE17 PA09Z PA10Z PD03A PE03Z PE08Z PF03Z PF08Z PF13Z

Claims (4)

[Claims] 1. A rotation speed detecting means for detecting an engine rotation speed of an internal combustion engine, an accelerator opening detecting means for detecting an accelerator opening according to a depression amount of an accelerator pedal, and a throttle opening of a throttle valve for the accelerator. A control amount calculating means for calculating a control amount for matching the throttle opening set on the basis of the opening, and an actuator driven based on the control amount calculated by the control amount calculating means for controlling the throttle valve of the throttle valve. Throttle control means for controlling the opening degree, wherein the throttle control means, when the engine rotation speed is equal to or higher than a predetermined rotation speed, regardless of the accelerator opening degree, opens the throttle valve. The engine speed is controlled to a predetermined target throttle opening degree set according to the operating state of the internal combustion engine. Throttle control apparatus for an internal combustion engine that. 2. The throttle control means, when the engine rotation speed becomes equal to or higher than a predetermined rotation speed, also uses rotation speed control by fuel cut for the internal combustion engine regardless of the magnitude of the accelerator opening. The throttle control device for an internal combustion engine according to claim 1, wherein the throttle opening of the throttle valve is controlled to a predetermined target throttle opening set according to an operating state of the internal combustion engine. 3. The target throttle opening is set according to at least one of a gear position of a transmission and a load of the internal combustion engine.
A throttle control device for an internal combustion engine according to claim 1. 4. The target throttle opening is corrected according to at least one of atmospheric pressure, intake air temperature, cooling water temperature, oil temperature of lubricating oil of the internal combustion engine, and oil temperature of the transmission. The throttle control device for an internal combustion engine according to any one of claims 1 to 3.