JP2000320347A - Throttle controller for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely eliminate deposits formed in a throttle valve edge part and on an intake passage inside wall in a throttle valve arrangement part by providing a throttle control means for reciprocating a throttle valve within a predetermined area including the front and rear parts of the position, in which the throttle valve is fully closed. SOLUTION: During the operation of a vehicle, a CPU 29 computes a target throttle opening of a throttle valve 7 on the basis of an output signal the like from an accelerator sensor 11, and drives and controls a direct-acting torque motor 8 for regulating the opening of the throttle valve 7. At starting times when an ignition switch 27 is switched from off to on by means of the CPU 29, throttle control is carried out for eliminating adhering objects such as deposits formed in the valve element 7a edge part in the throttle valve 7 and on the intake pipe 4 inside wall face. That is, the valve element 7a in the throttle valve 7 is reciprocated within a prescribed area including the front and back parts of the valve element 7a full opening position, so that the adhering objects can be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a technique for controlling a throttle valve provided in an intake passage of an internal combustion engine mounted on an automobile or the like.

[0002]

2. Description of the Related Art In an internal combustion engine mounted on an automobile, particularly an internal combustion engine fueling gasoline, a throttle valve provided in an intake passage and an accelerator pedal provided in a vehicle compartment are connected via a wire mechanism or a link mechanism. 2. Description of the Related Art There is known a technique of adjusting the intake air amount of an internal combustion engine by mechanically connecting and opening and closing a throttle valve in conjunction with an accelerator pedal.

In recent years, with the development of electronic control technology for internal combustion engines, there has been proposed a technology for electronically controlling a throttle valve so as to supply an optimal intake air amount to the internal combustion engine according to the state of the internal combustion engine and the vehicle. I have.

[0004] As such a technique, for example, a starter for an internal combustion engine described in Japanese Patent Application Laid-Open No. 60-11639 is known. This internal combustion engine starting device is provided with a signal generating device for reciprocating the throttle valve to a fully open position at a starting position of a start switch of the engine in an electronic control device for controlling a butterfly type throttle valve of a carburetor, and the throttle valve. And a relay switch for closing the drive circuit of the starting motor after the reciprocation of the motor.

In the starter for an internal combustion engine thus configured, when the start switch is operated to the start position at the start of the internal combustion engine, the throttle valve is once turned from the fully closed position to the fully open position, and the throttle valve is turned. By operating the starter motor when it is turned to the fully open position, a fuel-air mixture is supplied to the internal combustion engine without the driver having to operate the accelerator pedal when the engine is started, improving the startability of the internal combustion engine. They are trying to squeeze.

[0006]

In an internal combustion engine mounted on an automobile, an exhaust gas flowing through an exhaust passage is intended to reduce nitrogen oxides (NO _x ) contained in exhaust gas discharged from the internal combustion engine. An exhaust gas recirculation device (EGR device) that recirculates a part of the air to the intake passage is known.

In the above-described EGR device, the exhaust gas is usually recirculated to a surge tank provided immediately downstream of the throttle valve. Therefore, when the intake air pulsation occurs due to the return of the intake air, the EGR gas contains the exhaust gas. It is conceivable that the oil component or the like adhered to the throttle valve or the portion of the inner wall surface of the intake passage where the throttle valve is disposed.

If the deposits are formed by solidification of components adhering to the throttle valve and the inner wall of the intake passage, the cross-sectional area of the intake passage in the portion where the throttle valve is disposed changes, and the stability of the intake air amount is impaired. There is a risk of malfunction of the valve.

On the other hand, Japanese Unexamined Patent Publication No. Sho 60-1163 describes the above.
In the starter for an internal combustion engine described in Japanese Patent Application Laid-Open No. 9-205, only a butterfly type throttle valve (throttle valve) is reciprocated from a fully closed position to a fully open position, so that a deposit formed on an edge of the throttle valve, It becomes difficult to remove the deposit formed on the inner wall of the intake passage at the throttle valve arrangement portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and relates to a technique for controlling a throttle valve which can be opened and closed independently of an accelerator pedal. It is an object of the present invention to reliably remove deposits formed on the inner wall of the intake passage, to ensure the stability of the intake air amount, and to prevent malfunction of the throttle valve.

[0011]

The present invention employs the following means in order to solve the above-mentioned problems.
That is, the throttle control device for an internal combustion engine according to the present invention includes a throttle valve provided in an intake passage of the internal combustion engine and capable of opening and closing independently of an accelerator pedal, and before and after a position where the throttle valve is fully closed. Throttle control means for reciprocating the throttle valve in a predetermined range.

In the throttle control device for an internal combustion engine configured as described above, the throttle valve is located at a position further rotated in the closing direction than the fully closed position, while the conventional throttle valve operates starting from the fully closed position. Will operate from the starting point.

[0013] The throttle control means controls the throttle valve in a predetermined range including before and after the position where the throttle valve is fully closed, in other words, in a predetermined range including before and after the position where the edge of the throttle valve is closest to the inner wall of the intake passage. Is reciprocated.

In this case, when the throttle valve passes through the fully closed position during the reciprocating operation of the throttle valve,
Because the edge of the throttle valve and the inner wall of the intake passage are close to each other,
Deposits formed on the edge of the throttle valve and on the inner wall of the intake passage are scraped off.

The throttle control means may make the throttle valve reciprocate a predetermined number of times repeatedly in the predetermined range in order to surely scrape off the deposit formed on the edge of the throttle valve and the inner wall of the intake passage. .

The timing for causing the throttle valve to reciprocate within the predetermined range is such that the operation of the throttle valve does not affect the operating state of the internal combustion engine, such as when the internal combustion engine is started or when the operation of the internal combustion engine is stopped. Time is preferred.

When the internal combustion engine is in a non-idle operation state, the throttle control means operates the throttle valve in a range on the positive side from the fully closed position to adjust the intake air amount of the internal combustion engine. When the engine is in an idle operation state, the throttle valve may be operated in a range on the negative side from the fully closed position to adjust the intake air amount of the internal combustion engine.

Here, the range on the positive side from the fully closed position is
The range on the valve opening direction side from the fully closed position is referred to, and the range on the negative side from the fully closed position is the range on the valve closing direction side from the fully closed position.

With this configuration, when the operating state of the internal combustion engine shifts from the non-idle operating state to the idle operating state, and when shifting from the idle operating state to the non-idle operating range, the throttle valve is fully closed. In this case, the deposit formed on the edge of the throttle valve and on the inner wall of the intake passage is scraped off.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a specific embodiment of a throttle control device according to the present invention will be described with reference to the drawings.

First Embodiment First, a first embodiment of the throttle control device according to the present invention will be described.

FIG. 1 is a diagram showing a schematic configuration of an internal combustion engine to which the throttle control device according to the present invention is applied. The internal combustion engine 1 shown in FIG. 1 is a four-cycle water-cooled gasoline engine having four cylinders. A transmission (T / M) 200 is connected to the internal combustion engine 1 via a clutch mechanism (or a torque converter) 100.

The transmission (T / M) 200 is
It is connected to wheels as driving wheels via a propeller shaft, a differential gear, and the like (not shown). In the power transmission system configured as described above, when the clutch mechanism 100 is in the engaged state, the torque of the output shaft (crankshaft) (not shown) of the internal combustion engine 1 is transmitted via the clutch mechanism 100 to the transmission (T / M). ) 200, decelerated or increased in transmission (T / M) 200, and then transmitted (T / M) 2
From 00, the power is transmitted to wheels as driving wheels via a propeller shaft, a differential gear, and the like.

An intake branch pipe 2 is connected to the internal combustion engine 1.
Each branch pipe of the intake branch pipe 2 communicates with a combustion chamber (not shown) of each cylinder via an intake port. The intake branch pipe 2 is connected to a surge tank 3, and the surge tank 3 communicates with an air cleaner box 5 via an intake pipe 4.

An air flow meter 6 for outputting an electric signal corresponding to the mass of fresh air flowing in the intake pipe 4 is provided in the middle of the intake pipe 4. The intake pipe 4 downstream of the air flow meter 6 is provided with a throttle valve 7 for adjusting the flow rate of fresh air flowing in the intake pipe 4.

As shown in FIG. 2, the throttle valve 7 has a valve body 7a having an outer diameter substantially equal to the inner diameter of the intake pipe 4, and both ends thereof are rotatable on the wall surface of the intake pipe 4. It is configured by integrally fixing the supported shaft 7b.

One end of the shaft 7b (the end located on the lower side in FIG. 2) protrudes out of the intake pipe 4, and the rotary shaft 80 of the linear motion torque motor 8 fixed to the outer wall of the intake pipe 4. Is linked to

The other end of the shaft 7b is connected to the intake pipe 4
And a lever 7c is formed at a protruding end of the lever 7c so as to protrude in a direction orthogonal to the axial direction of the shaft 7b. A return spring 70 that biases the lever 7c in a direction in which the shaft 7b and the valve body 7a close is connected to the lever 7c.

The lever 7c is provided on the outer wall of the intake pipe 4.
A stopper 73 is provided so as to prohibit the rotation in the valve closing direction at a predetermined position. The predetermined position is, for example, as shown in FIG. 3, assuming that the opening degree of the position where the valve element 7 a fully closes the flow path in the intake pipe 4 is “0 °”, and that the opening degree from the fully closed position When it is assumed that the opening on the valve side is a positive value and the opening on the valve closing side from the fully closed position is a negative value, the valve body 7a
Is set to a position where the opening degree is “−10 °”.

The throttle valve 7 shown in FIGS.
Then, when the direct-acting torque motor 8 is in a non-energized state,
The lever 7c is brought into contact with the stopper 73 by receiving the urging force of the return spring 70, and accordingly, the valve body 7a is fixed at an opening of “−10 °”.

On the other hand, in the throttle valve 7, when a drive current is supplied to the direct drive torque motor 8, the rotating shaft 80 of the direct drive torque motor 8 rotates in the valve opening direction. The rotating torque of the rotating shaft 80 is
is transmitted to the valve body 7a via the valve b, and the valve body 7a rotates in the valve opening direction. Then, when the rotational torque of the rotary shaft 80 and the urging force of the return spring 70 are balanced, the rotation of the valve 7a stops. At this time, by controlling the magnitude of the drive current supplied to the direct-acting torque motor 8, the opening of the valve body 7a can be adjusted.

Returning to FIG. 1, the throttle valve 7 is provided with a throttle position sensor 9 for outputting an electric signal corresponding to the opening of the throttle valve 7. An accelerator lever (not shown) that rotates in conjunction with an accelerator pedal 10 installed in the vehicle cabin is attached to the throttle valve 7, and an electrical signal (an electric signal (in accordance with the amount of rotation of the accelerator lever) is provided to the accelerator lever. Accelerator pedal 1
An accelerator position sensor 11 that outputs an electric signal according to the depression amount of 0) is attached.

In the intake system configured as described above, fresh air flowing into the air cleaner box 5 is guided to the intake pipe 4 after dust and dirt in the fresh air are removed by an air cleaner provided in the air cleaner box 5. I will The flow rate of fresh air guided to the intake pipe 4 is adjusted by a throttle valve 7 provided in the middle of the intake pipe 4. The fresh air whose flow rate has been adjusted by the throttle valve 7 is supplied from the intake pipe 4 to the surge tank 3 and then from the surge tank 3 to the intake branch pipe 2.
Is distributed to each branch pipe. Fresh air distributed to each branch pipe of the intake branch pipe 2 is guided to the intake port of the internal combustion engine 1 through each branch pipe, and is supplied to the combustion chamber of each cylinder via the intake port.

Each of the branch pipes of the intake branch pipe 2 has a fuel injection valve 13a, 13
b, 13c and 13d (hereinafter collectively referred to as fuel injection valves 13) are attached. A fuel distribution pipe 14 is connected to these fuel injection valves 13.
Is connected to a fuel pump (not shown).

Each fuel injection valve 13 is provided with the fuel injection valve 13.
Drive circuits 15a, 15b, 15c, 15
d (hereinafter collectively referred to as the drive circuit 15). In the fuel injection system configured as described above, the fuel stored in a fuel tank (not shown) is sucked out by the fuel pump and discharged toward the fuel distribution pipe 14. The fuel that has reached the fuel distribution pipe 14 is distributed to each fuel injection valve 13 by the fuel distribution pipe 14. Each fuel injection valve 13 opens when a drive current is applied by the drive circuit 15,
The fuel distributed from the fuel distribution pipe 14 is injected toward an intake port of the internal combustion engine 1. The fuel injected into the intake port is supplied to the combustion chamber of each cylinder while being mixed with fresh air supplied from the intake branch pipe 2 to the intake port.

The internal combustion engine 1 is provided with spark plugs 12a, 12b, 12c, and 12d (hereinafter collectively referred to as spark plugs 12) so as to face combustion chambers of respective cylinders. Each ignition plug 12 generates a spark when a drive current is applied, and a drive current is applied at a predetermined timing in the second half of the compression stroke or the first half of the expansion stroke of each cylinder to ignite the air-fuel mixture in the combustion chamber. It has become.

On the other hand, an exhaust branch 16 is connected to the internal combustion engine 1, and each branch of the exhaust branch 16 communicates with a combustion chamber of each cylinder via an exhaust port (not shown). Exhaust branch pipe 16
Is connected to an exhaust pipe 17, and the exhaust pipe 17 is connected downstream to a muffler (not shown).

In the middle of the exhaust pipe 17, exhaust from the internal combustion engine 1 is performed.
CO, NO contained in emitted exhaust _XHazardous gas such as
An exhaust purification catalyst 18 for purifying exhaust gas components is provided.
The exhaust purification catalyst 18 includes a three-way catalyst, an oxidation catalyst,
Selective reduction type NO_XCatalyst or NO stored and reduced_XCatalyst, etc.
Can be exemplified.

The exhaust pipe 1 upstream of the exhaust purification catalyst 18
An air-fuel ratio sensor 19 that outputs an electric signal corresponding to the air-fuel ratio of the exhaust gas flowing through the exhaust pipe 17 is attached to 7.

In the exhaust system configured as above, the air-fuel mixture burned in the combustion chamber of the internal combustion engine 1 is exhausted and discharged from the combustion chamber to an exhaust port. The exhaust gas discharged to the exhaust port is guided from the exhaust port to the intake pipe 17 via each branch pipe of the exhaust branch pipe 16.

The exhaust gas guided to the exhaust pipe 17 is
The harmful gas components contained in the exhaust gas are purified by an exhaust purification catalyst 18 provided in the middle of the exhaust gas 7 and then released into the atmosphere via a muffler.

The exhaust branch pipe 16 and the surge tank 3 are communicated with each other by an exhaust gas recirculation pipe (EGR pipe) 37, and a part of the exhaust gas flowing through the exhaust branch pipe 16 is returned to the surge tank 3. It is possible to do.

In the middle of the EGR pipe 37, an exhaust gas recirculation amount adjustment for adjusting the flow rate of the exhaust gas flowing in the EGR pipe 37, in other words, the flow rate of the exhaust gas recirculated from the exhaust branch pipe 16 to the surge tank 3. A valve (EGR valve) 38 is provided.

The internal combustion engine 1 has a crank position sensor 2 for outputting a pulse signal each time a crankshaft (not shown) rotates a predetermined angle (for example, 10 degrees).
0 and a water temperature sensor 21 that outputs an electric signal corresponding to the temperature of the cooling water flowing in the water jacket formed in the internal combustion engine 1.

The internal combustion engine 1 configured as described above has an electronic control unit (Electronic Control Unit) for engine control.
ol Unit (ECU) 22 is also provided. ECU 22
Input ports detect the positions of an air flow meter 6, a throttle position sensor 9, an accelerator position sensor 11, an air-fuel ratio sensor 19, a crank position sensor 20, a water temperature sensor 21, a starter switch 26, and a shift lever installed in the vehicle compartment. Shift position sensor 23, a brake switch 24 for detecting the operation / non-operation of the brake pedal 10 provided in the vehicle interior, and an ignition switch (IG.
SW) 27 and the like are connected via electric wiring, and output signals of the various sensors are input to the ECU 22.

The output port of the ECU 22 is connected to the direct-acting torque motor 8, the ignition plug 12, the drive circuit 15, the EGR valve 38, and the like via electric wiring. The ECU 22 uses the output signals of the various sensors described above as parameters. , The direct-acting torque motor 8, the ignition plug 12, the drive circuit 15, the EGR valve 38, and the like.

Here, as shown in FIG. 4, the ECU 22 connects the CPs connected to each other by a bidirectional bus 28.
U29, ROM30, RAM31, and backup RAM
32. The bidirectional bus 28 has A /
The first input interface circuit 33 is connected via the D converter 36, and the second input interface circuit 34 and the output interface circuit 35 are connected.

The first input interface circuit 33 is connected to the air flow meter 6, the throttle position sensor 9, the accelerator position sensor 11, the air-fuel ratio sensor 19, and the water temperature sensor 21 via electric wiring. First
The input interface circuit 33 inputs an output signal from each of the above-described sensors to the A / D converter 36.

The A / D converter 36 converts the output signals of the various sensors input by the first input interface circuit 33 from the analog signal format to the digital signal format, and then converts the output signals from the CPU 29 and the RAM 3 via the bidirectional bus 28.
Send to 1.

The second input interface circuit 34 includes the crank position sensor 20 and the shift position sensor 2
3, the brake switch 24, the vehicle speed sensor 25, the starter switch 26, and the ignition switch 27 are connected via electric wiring. The second input interface circuit 34 transmits the output signal of each sensor described above to the CPU 29 and the RAM 31 via the bidirectional bus 28.

The output interface circuit 35 is connected to the direct-acting torque motor 8, the ignition plug 12, the drive circuit 15, and the EGR valve 38 via electric wiring. The output interface circuit 35 transmits various control signals output from the CPU 29 to the direct-acting torque motor 8, the ignition plug 12, the drive circuit 15, and the EGR valve 38.

The ROM 30 stores a fuel injection amount control routine for determining a fuel injection amount to be injected from each fuel injection valve 13 and a fuel injection timing control routine for determining a timing at which fuel is injected from each fuel injection valve 13. And an ignition timing control routine for determining the ignition timing of each cylinder, a throttle opening control routine for determining the opening of the throttle valve 7, an EGR control routine for determining the opening of the EGR valve 38, and the like. An application program and various control maps are stored.

The control map stored in the ROM 30 includes, for example, a fuel injection amount control map showing the relationship between the operating state of the internal combustion engine 1 and the fuel injection amount, and the relationship between the operating state of the internal combustion engine 1 and the fuel injection timing. A fuel injection timing control map, an ignition timing control map indicating the relationship between the operating state of the internal combustion engine 1 and the ignition timing, and a relationship between the operating state of the internal combustion engine 1 and the target opening of the throttle valve 7 (target throttle opening). Throttle control map, operating state of the internal combustion engine 1 and EGR
9 is an EGR control map or the like showing a relationship with the opening of the valve 38.

The RAM 31 stores an output signal of each sensor and a CP.
The calculation result of U29 is stored. The calculation result of the CPU 29 is, for example, an engine speed calculated based on the output signal of the crank position sensor 20 and the like. Thus, the data stored in the RAM 31 is rewritten to the latest data every time the crank position sensor 20 outputs a pulse signal, for example.

The backup RAM 32 is a nonvolatile memory that retains data even after the engine stops. CPU 29
Operates according to application programs stored in the ROM 30, executes fuel injection control, ignition control, EGR control, and the like using output signals of various sensors as parameters, and executes throttle control, which is the gist of the present invention.

Hereinafter, the throttle control in this embodiment will be described. The CPU 29 basically calculates the target throttle opening of the throttle valve 7 based on the output signal of the accelerator position sensor 11 and the like, and adjusts the actual throttle opening so that the actual opening of the throttle valve 7 matches the target throttle opening. The dynamic torque motor 8 is controlled.

In the present embodiment, in addition to the normal throttle control described above, the CPU 29
The throttle control for removing deposits and the like formed on the portion where the valve body 7a is disposed at the edge of the valve body 7a and the inner wall surface of the intake pipe 4 is executed.

Here, the internal combustion engine 1 shown in this embodiment
In an internal combustion engine provided with an EGR mechanism that recirculates a part of the exhaust gas to the intake system as shown in FIG.
In some cases, deposits such as oil components contained in the gas adhere to the valve body 7 a of the throttle valve 7 and the inner wall surface of the intake pipe 4. In particular, the edge of the valve body 7a,
If a deposit is formed on the inner wall surface of the intake pipe 4 at the position where the valve element 7a is disposed, there is a possibility that operation failure of the valve element 7a and stability of the intake air amount may be impaired.

Therefore, in the present embodiment, the valve 7a of the throttle valve 7 is reciprocated within a predetermined range including before and after the fully closed position immediately before the start of the internal combustion engine 1, thereby obtaining the valve 7a.
At the edge of the inner wall surface and the inner wall surface of the intake pipe 4, the deposit on the portion where the valve element 7a is disposed is removed.

More specifically, the CPU 29 executes a startup throttle control routine as shown in FIG. 5 immediately before the start of the internal combustion engine 1 to remove deposits and other deposits.

In the starting throttle control routine shown in FIG. 5, the ignition switch (IG.SW) 27 is switched from off to on (input of an on signal from the ignition switch (IG.SW) 27).
This is a routine executed by using as a trigger.

In the starting throttle control routine, CP
U29 determines in S501 that the throttle valve 7 has "-1".
The energization of the drive current to the direct-acting torque motor 8 is started so that the valve opens from the opening of 0 ° to the opening of + 3 °.

At this time, the magnitude of the drive current applied to the direct-acting torque motor 8 is determined by the fact that the urging force of the return spring 70 and the torque of the direct-acting torque motor 8 are:
The size is set to be balanced at “+ 3 °”,
It is determined experimentally in advance.

At S502, the CPU 29 receives the output signal of the throttle position sensor 9 and determines whether or not the actual opening of the throttle valve 7 has reached an opening of "+ 3 °" or more.

If it is determined in step S502 that the actual opening of the throttle valve 7 has not reached the opening of "+ 3 °" or more, the CPU 29 determines that the actual opening of the throttle valve 7 has reached "+ 3 °" or more. The process of S502 is repeatedly executed until the value reaches.

If it is determined in step S502 that the actual opening of the throttle valve 7 has reached an opening of “+ 3 °” or more, the CPU 29 proceeds to step S503 to stop energizing the direct-acting torque motor 8. . In this case, since the torque of the direct-acting torque motor 8 becomes “zero”, the throttle valve 7 is closed from the opening of “+ 3 °” to the opening of “−10 °” by the urging force of the return spring 70. Is done.

In S504, the CPU 29 receives the output signal of the throttle position sensor 9 and determines whether or not the actual opening of the throttle valve 7 has returned to the opening of "-10 °".

If it is determined in S504 that the actual opening of the throttle valve 7 has not returned to the opening of “−10 °”, the CPU 29 determines that the actual opening of the throttle valve 7 is “−10 °”. The process of S504 is repeatedly executed until the opening degree returns to.

If it is determined in step S504 that the actual opening of the throttle valve 7 has returned to the opening of "-10 °", the CPU 29 proceeds to step S505, in which the CPU 31 stores the counter storage area set in the predetermined area of the RAM 31. Value: C is incremented by one. The counter storage area is an area that is incremented by "1" every time the throttle valve 7 makes one reciprocation in the range from the opening of "-10" to the opening of "+3".

In S506, the CPU 29 executes the processing in S50.
The value of the counter storage area updated in step 5: C is equal to or greater than "3", that is, the throttle valve 7 is set to "-10".
It is determined whether the opening / closing operation has been performed three times or more between the opening degree of “°” and the opening degree of “+ 3 °”.

If it is determined in step S506 that the value of the counter storage area: C is less than "3",
U29 executes the processes of S501 to S505 again. If it is determined in S506 that the value of the counter storage area: C is equal to or more than “3”, the CP
U29 proceeds to S507, and resets the value: C of the counter storage area to “0”.

In S508, the CPU 29 supplies drive power to a starter motor (not shown),
Is started, and the execution of this routine ends. As described above, the CPU 29 executes the start-time throttle control routine, so that the throttle valve 7 reciprocates in the range between the opening of “−10 °” and the opening of “+ 3 °” three times immediately before the start of the internal combustion engine 1. Will do.

When the throttle valve 7 reciprocates between the opening degree of “−10 °” and “+ 3 °”, the valve element 7a moves from the fully closed position to the fully closed position from the fully closed position (negative side) on the outward path. In addition to the operation toward the valve opening side (positive side), in the return path, the operation from the valve opening side (positive side) from the fully closed position to the valve closing side (negative side) from the fully closed position. That is, the throttle valve 7
Of the valve element 7a is in the fully closed position (opening “0”) by one reciprocating operation.
° ") twice.

Here, the clearance between the edge of the valve element 7a of the throttle valve 7 and the inner wall surface of the intake pipe 4 becomes substantially zero at the fully closed position, so that when the valve element 7a passes through the fully closed position. On the inner wall surface of the intake pipe 4, deposits such as a portion where the valve element 7 a is disposed and a deposit formed on an edge of the valve element 7 a are scraped off. In particular, in the present embodiment, the valve element 7a repeats the operation of passing the fully closed position three times from both the direction from the positive side to the negative side and the direction from the negative side to the positive side. At the edge of the valve and the inner wall surface of the intake pipe 4, the deposits on the portion where the valve element 7a is disposed are reliably removed.

On the other hand, according to the above-described start-time throttle control routine, the substantial start control of the internal combustion engine 1 is performed when the throttle valve 7 is moved between the opening degree of "-10 °" and the opening degree of "+ 3 °". Is repeated three times, but since the three reciprocating operations of the throttle valve 7 are completed in a very short time of about “60 msec”, the driver does not feel uncomfortable.

As described above, the throttle control means according to the present invention is realized by the CPU 29 executing the starting throttle control routine. Therefore, according to the throttle control device for an internal combustion engine according to the present embodiment, deposits such as deposits adhere to the edge of the valve element 7a of the throttle valve 7 and the portion where the valve element 7a is disposed on the inner wall surface of the intake pipe 4. However, when the start operation of the internal combustion engine 1 is performed, the deposit on the edge portion of the valve body 7a and on the inner wall surface of the intake pipe 4 at the position where the valve body 7a is disposed is surely scraped off. The malfunction of the throttle valve 7 and the stability of the intake air amount are not impaired.

Embodiment 2 Next, a second embodiment of the throttle control device according to the present invention will be described with reference to FIG. Here, a configuration different from the above-described embodiment will be described, and a description of a similar configuration will be omitted.

In the first embodiment, the internal combustion engine 1
Although the example in which the throttle valve 7 is controlled to remove deposits and the like immediately before the start of the engine has been described, in the present embodiment, the throttle valve 7 is removed to remove deposits and the like immediately after the internal combustion engine 1 stops operating. 7 will be described.

In this case, the CPU 29 executes an operation-stop-time throttle control routine as shown in FIG. FIG.
In the operation-stop-time throttle control routine shown in FIG. 5, the ignition switch (IG.SW) 27 is switched from on to off (ignition switch (IG.S.
W) that an OFF signal is input from 27) as a trigger.

In the stop-time throttle control routine,
In step S601, the CPU 29 controls the drive circuit 15 to stop the supply of the drive current to the fuel injection valve 13, and stops the supply of the drive current to the spark plug 12, thereby substantially stopping the operation of the internal combustion engine 1. Stop.

In step S602, the CPU 29 starts energization of the drive current to the direct-acting torque motor 8 so that the throttle valve 7 performs the opening operation from the opening of “−10 °” to the opening of “+ 3 °”.

In S603, the CPU 29 receives the output signal of the throttle position sensor 9 and determines whether or not the actual opening of the throttle valve 7 has reached an opening of "+ 3 °" or more.

If it is determined in step S603 that the actual opening of the throttle valve 7 has not reached an opening of "+ 3 °" or more, the CPU 29 determines that the actual opening of the throttle valve 7 has reached "+ 3 °" or more. The process of S603 is repeatedly executed until the number of times reaches.

If it is determined in step S603 that the actual opening of the throttle valve 7 has reached an opening of "+ 3 °" or more, the CPU 29 proceeds to step S604 to stop energizing the direct-acting torque motor 8. . In this case, since the torque of the direct-acting torque motor 8 becomes “zero”, the throttle valve 7 is closed from the opening of “+ 3 °” to the opening of “−10 °” by the urging force of the return spring 70. Is done.

In S605, the CPU 29 receives the output signal of the throttle position sensor 9 and determines whether or not the actual opening of the throttle valve 7 has returned to the opening of “−10 °”.

If it is determined in step S605 that the actual opening of the throttle valve 7 has not returned to the opening of “−10 °”, the CPU 29 determines that the actual opening of the throttle valve 7 is “−10 °”. The process of S605 is repeatedly executed until the opening degree returns to the predetermined value.

If the CPU 29 determines in step S605 that the actual opening of the throttle valve 7 has returned to the opening of “−10 °”, the CPU 29 proceeds to step S606, in which the counter storage area set in the predetermined area of the RAM 31 is stored. Value: C is incremented by one.

In S607, the CPU 29 executes the processing in S60.
6, whether the value of the counter storage area updated in step C is equal to or more than "3", that is, whether the throttle valve 7 is "-10"
It is determined whether the opening / closing operation has been performed three times or more between the opening degree of “°” and the opening degree of “+ 3 °”.

If it is determined in step S607 that the value of the counter storage area: C is less than "3",
U29 executes the processing of S602 to S606 again. If it is determined in step S607 that the value of the counter storage area: C is equal to or more than “3”,
U29 proceeds to S608, and resets the value: C of the counter storage area to “0”.

At S609, the CPU 29
Is turned off from on, and the execution of this routine ends. As described above, the CPU 29 executes the stop-time throttle control routine so that the throttle valve 7 is set to “−10 °” immediately after the operation of the internal combustion engine 1 is stopped.
And the opening of “+ 3 °” reciprocates three times.

As a result, deposits adhering to the edge of the valve element 7a of the throttle valve 7 and the portion where the valve element 7a is disposed on the inner wall surface of the intake pipe 4 reciprocate the throttle valve 7 immediately after the operation of the internal combustion engine 1 stops. The operation is surely removed by the operation, the malfunction of the throttle valve 7 does not occur, and the stability of the intake air amount is secured.

Embodiment 3 Hereinafter, a third embodiment of the throttle control device according to the present invention will be described with reference to FIG. Here, a configuration different from that of the above-described first embodiment will be described, and a description of a similar configuration will be omitted.

In the first embodiment, the internal combustion engine 1
Although the example in which the deposits and the like are removed immediately before the start of the engine has been described, in the present embodiment, the example in which the deposits and the like are removed during the operation of the internal combustion engine 1 will be described.

In this case, the CPU 29 executes an operating throttle control routine as shown in FIG. The operating throttle control routine shown in FIG. 7 is a routine that is repeatedly executed at predetermined time intervals (for example, every time the crank position sensor 20 outputs a pulse signal) when the internal combustion engine 1 is in an operating state.

In the operation-time throttle control routine, CP
U29 determines in S701 whether or not the operation state of the internal combustion engine 1 is in the idle operation region. As a method of determining the idling operation region, the determination is made on the condition that the output signal (vehicle speed) of the vehicle speed sensor 25 is equal to or lower than a predetermined speed and the output signal (accelerator opening) of the accelerator position sensor 11 is “0”. The method can be illustrated.

If it is determined in step S701 that the operation state of the internal combustion engine 1 is in the non-idle operation range,
U29 proceeds to S702 and controls the throttle valve 7 in the range (0 ° to (+ 90 °)) on the positive side from the fully closed position.

For example, the CPU 29 calculates a target throttle opening using the output signal (accelerator opening) of the accelerator position sensor 11 as a basic parameter. CPU 29
Calculates the magnitude of the drive current to be applied to the direct drive torque motor 8 in driving the throttle valve 7 to the target throttle opening. The CPU 29 applies the calculated drive current to the linear motion torque motor 8.

CPU that has completed the processing of S702
In step 29, the execution of this routine is temporarily terminated, and this routine is executed again after a predetermined time has elapsed. that time,
If the operation state of the internal combustion engine 1 has shifted from the non-idle operation area to the idle operation area, the CPU 29 determines in S701 that the operation state of the internal combustion engine 1 is in the idle operation area, and proceeds to S703.

In S703, the CPU 29 sets the throttle valve 7 in a range on the positive side from the fully closed position (0 ° to (+ 90 °)).
From the fully closed position to a range on the negative side (0 ° to (−10 °)) from the fully closed position, and then executes idle speed control in the range on the negative side from the fully closed position.

For example, the CPU 29 calculates a target idle speed by using the output signal of the water temperature sensor 21 (engine cooling water temperature), the load of accessories such as an air conditioner compressor, and the like as parameters.

The CPU 29 calculates the actual engine speed based on the time interval at which the crank position sensor 20 outputs the pulse signal. The CPU 29 compares the target idle speed with the actual engine speed.

When the actual engine speed is lower than the target idle speed, the CPU 29 controls the direct-acting torque motor 8 to increase the intake air amount of the internal combustion engine 1 to increase the engine speed. When the engine speed is higher than the target idle speed, the direct-acting torque motor 8 is used to reduce the intake air amount of the internal combustion engine 1 to lower the engine speed.
Control.

Here, in the range on the negative side from the fully closed position, the substantial flow path in the intake pipe 4 becomes wider as the opening of the throttle valve 7 advances in the valve closing direction (the more it moves toward the negative side). Therefore, C
The PU 29 controls the direct-acting torque motor 8 to drive the throttle valve 7 in the valve closing direction when increasing the intake air amount of the internal combustion engine 1, and controls the throttle motor 7 when decreasing the intake air amount of the internal combustion engine 1 The linear motion torque motor 8 is controlled to drive the valve 7 in the valve opening direction.

Returning to FIG. 7, the CPU 29 that has completed the processing of S703 executes the processing of S701 and subsequent steps again. At this time, if it is determined in S701 that the operation state of the internal combustion engine 1 has shifted from the idle operation region to the non-idle operation region, the CPU 29 moves the throttle valve 7 from the region on the negative side of the fully closed position to the fully closed position in S702. It is driven to the positive side area, and then driven to the target throttle opening.

As described above, when the operation state of the internal combustion engine 1 shifts from the non-idle operation region to the idle operation region by the CPU 29 executing the operating throttle control routine, the valve 7a of the throttle valve 7 The valve is closed from the position on the positive side of the closed position to the position on the negative side of the fully closed position, and passes through the fully closed position from the positive side to the negative side.

When the operating state of the internal combustion engine 1 shifts from the idle state to the non-idle state, the valve body 7a of the throttle valve 7 moves from the position on the negative side of the fully closed position to the position on the positive side of the fully closed position. , And passes through the fully closed position from the negative side to the positive side.

As a result, the valve element 7a of the throttle valve 7 is
When the operating state of the internal combustion engine 1 changes between the idle operation region and the non-idle operation region, the internal combustion engine 1 reciprocates between a position on the negative side from the fully closed position and a position on the positive side from the fully closed position.

Therefore, the deposits adhering to the edge of the valve element 7a of the throttle valve 7 and the portion where the valve element 7a is disposed on the inner wall surface of the intake pipe 4 are surely removed by the reciprocating operation of the valve element 7a as described above. As a result, the throttle valve 7 does not malfunction, and the stability of the intake air amount is secured.

[0109]

In the throttle control device for an internal combustion engine according to the present invention, the throttle valve is moved in a predetermined range including before and after the fully closed position, in other words, before and after the position where the edge of the throttle valve is closest to the inner wall of the intake passage. The reciprocating operation is performed in a predetermined range including the range.

In this case, deposits such as deposits formed on the edges of the throttle valve and on the inner wall of the intake passage are scraped off when the throttle valve passes through the fully closed position. Therefore, according to the throttle control device of the present invention, the deposit attached to the throttle valve arrangement portion at the edge of the throttle valve and the inner wall of the intake passage is reliably scraped off, and the throttle valve malfunctions. As a result, the stability of the intake air amount is also ensured.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an internal combustion engine to which the present invention is applied.

FIG. 2 is a diagram showing a detailed configuration of a throttle valve.

FIG. 3 is a diagram illustrating the operation of a throttle valve.

FIG. 4 is a block diagram showing an internal configuration of an ECU.

FIG. 5 is a flowchart showing a throttle control routine at startup.

FIG. 6 is a flowchart showing a throttle control routine at the time of operation stop;

FIG. 7 is a flowchart showing a throttle control routine during operation.

[Description of Signs] 1 ... Internal combustion engine 2 ... Intake branch pipe 3 ... Surge tank 4 ... Intake pipe 7 ... Throttle valve 7a ... Valve body 7b ... Shaft 7c ... Lever 70 ··· Return spring 8 ··· Linear motion torque motor 9 ··· Throttle position sensor 10 ··· Accelerator pedal 11 ··· Accelerator position sensor 16 ··· Exhaust branch pipe 22 ··· ECU 29 ··· CPU 30 ··· ROM 37 ·・ EGR pipe 38 ・ ・ EGR valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 41/06 310 F02D 41/06 310 315 315 F Term (Reference) 3G065 CA36 DA05 EA01 EA03 EA06 GA05 GA09 GA10 GA11 GA29 GA31 GA41 GA46 HA21 HA22 JA04 JA09 JA11 KA02 3G301 HA01 HA06 JB02 KA01 KA07 KA28 LA03 LB02 LC03 PA01Z PE01Z PE08Z PF01Z PF03Z PF05Z PF08Z

Claims (4)

[Claims] 1. A throttle valve provided in an intake passage of an internal combustion engine and capable of opening and closing independently of an accelerator pedal, and reciprocating the throttle valve in a predetermined range including before and after a position where the throttle valve is fully closed. And a throttle control means for controlling the throttle of the internal combustion engine. 2. The throttle control of an internal combustion engine according to claim 1, wherein the throttle control means drives the throttle valve so that the throttle valve reciprocates in the predetermined range when the internal combustion engine is started. apparatus. 3. The throttle according to claim 1, wherein the throttle control means drives the throttle valve such that the throttle valve reciprocates within the predetermined range when the operation of the internal combustion engine is stopped. Control device. 4. When the internal combustion engine is in a non-idle operation state, the throttle control means drives the throttle valve to open and close in a range on the positive side from a fully closed position to adjust an intake air amount of the internal combustion engine. 2. The intake air amount of the internal combustion engine when the internal combustion engine is in an idling operation state, wherein the throttle valve is driven to open and close in a negative range from the fully closed position. Throttle control device for internal combustion engine.