JP2002038975A - Controller for opening of throttle valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent uneven abrasion from being generated on a driving part of a throttle valve or a detecting part of a throttle sensor caused by vibration even in a case where vibration generated with the operation of an internal combustion engine is transmitted, in a controller for the opening of the throttle valve. SOLUTION: An electronic controller 50 sets the target opening of a throttle valve 20 on the basis of the engine operating state and controls drive of a throttle motor 40 so that the target opening may coincide with the actual opening detected by a throttle sensor 30. The electronic controller 50 controls drive of the throttle motor 40 under the condition that the target opening based on the engine operating state is not less than the specified opening so that the opening of the throttle valve 20 may be periodically fluctuated by taking the target opening as a reference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle valve opening control device for controlling the opening of an internal combustion engine by opening and closing the throttle valve by an actuator.

[0002]

2. Description of the Related Art This type of opening control device includes a throttle motor for opening and closing a throttle valve, a throttle sensor for detecting the opening of the throttle valve, and drive control of the throttle motor based on a detection signal from the throttle sensor. An electronic control unit. The throttle motor and the valve shaft of the throttle valve are usually connected via a plurality of gears. That is, a drive gear is provided on the rotation shaft of the throttle motor, and the drive gear is meshed with a driven gear provided on the valve shaft. The driving force of the throttle motor is transmitted to the valve shaft via these gears. The throttle valve is opened and closed based on the driving force of a throttle motor transmitted to the valve shaft.

As the throttle sensor, a well-known contact type sensor having a detection pattern formed of a resistor or the like and a contact sliding on the detection pattern as the valve shaft rotates is generally used. . In this throttle sensor, since the detection voltage changes according to the position of the contact on the detection pattern, the rotation phase of the valve shaft, that is, the opening of the throttle valve, is detected based on the detection voltage.

In the opening control device, the throttle motor is driven and controlled by the electronic control device so that the actual opening detected by the throttle sensor and the target opening set based on the engine operating state match. You.

[0005]

By the way, vibration accompanying the operation of the internal combustion engine is constantly transmitted to these throttle motors and throttle sensors. Therefore, if the target opening is kept constant for a long period of time, the following problems cannot be ignored.

That is, regarding the driving portion of the throttle valve, the collision of the meshing surfaces of the gears is repeated by vibration without changing the meshing portions of the driving gear and the driven gear. There is a possibility that local wear at the engagement portion may progress. Further, regarding the detection unit of the throttle sensor, since the contact vibrates on the detection pattern without changing the position of the contact, there is a possibility that local wear may progress in the detection pattern.

As described above, when uneven wear occurs in the drive section of the throttle valve and the detection section of the throttle sensor, the throttle valve cannot be opened and closed smoothly, or the detection accuracy when detecting the opening degree is reduced. As a result, the durability of the entire device is reduced.

The present invention has been made in view of such conventional circumstances, and has as its object the case where vibration generated during operation of an internal combustion engine is transmitted to a throttle valve opening control device. Another object of the present invention is to suppress the occurrence of uneven wear in the drive section of the throttle valve and the detection section of the throttle sensor due to the vibration.

[0009]

The means for achieving the above object and the effects thereof will be described below. (Claim 1) The invention according to claim 1 includes an actuator for opening and closing a throttle valve of an internal combustion engine, and a throttle sensor for detecting an opening of the throttle valve. In a throttle valve opening control device that drives and controls the actuator so as to match a target opening set based on the engine operating state, when the engine operating state is a specific operating state, the specific operating state And a drive control means for controlling the drive of the actuator so as to suppress the actual opening of the throttle from always becoming a constant opening.

According to the above configuration, even if the engine operating state is maintained at a specific operating state for a long period of time, it is avoided that the actual opening of the throttle valve is maintained at a constant opening. . Therefore, the frequency with which the actual opening of the throttle valve is kept constant for a long period of time is reduced, and uneven wear due to vibration during engine operation at a specific portion of the drive unit of the throttle valve or the detection unit of the throttle sensor is generated. Is suppressed.

The invention according to claim 2 includes an actuator for opening and closing the throttle valve of the internal combustion engine, and a throttle sensor for detecting the opening of the throttle valve. In a throttle valve opening control device that drives and controls the actuator such that the opening matches a target opening set based on the engine operating state, the actual opening of the throttle valve is based on the target opening. And a drive control means for controlling the drive of the actuator so as to change periodically.

According to the above configuration, since the opening of the throttle valve is periodically changed with reference to the target opening, even if the target opening based on the engine operating state is kept constant for a long period of time. Even if it does, the actual opening of the throttle valve will not be kept constant. Therefore, the occurrence of uneven wear due to vibration during engine operation at a specific portion of the drive section of the throttle valve or the detection section of the throttle sensor is suppressed.

According to a third aspect of the present invention, in the throttle valve opening control device according to the second aspect, the throttle valve is controlled based on the set target opening. The drive control means is configured to variably set at least one of a variation width and a cycle when the actual opening degree is varied in a cycle, and to perform drive control of the actuator.

Even if the fluctuation width of the periodic fluctuation and its period are the same, the effect of the execution of the periodic fluctuation on the engine operation such as the fluctuation of the engine output differs depending on the opening degree of the throttle valve. In this regard, in the above configuration, at least one of the fluctuation width of the periodic variation and the cycle thereof is variably set in accordance with the magnitude of the target opening when the actual opening degree varies, so that the uneven wear is suppressed and the engine This makes it possible to maintain stable operation.

According to a fourth aspect of the present invention, there is provided the throttle valve opening control device according to any one of the first to third aspects, wherein the following conditions (A) to (C) are satisfied: (A) the set target opening is kept constant for a predetermined period; (B) the set target opening is within a predetermined range; (C) the set target opening The drive control means is configured to execute the drive control of the actuator when at least one of the following conditions is satisfied: a variation amount of the engine output with respect to the unit variation amount is equal to or less than a predetermined value.

According to the above configuration, the above conditions (A) to (A)
When at least one or more of (C) is satisfied, the drive control of the actuator described above is executed. That is, only the condition (A) is satisfied, only the condition (B) is satisfied, only the condition (C) is satisfied, the condition (A) or (B) is satisfied, the condition (A) or (C) is satisfied, and the condition ( The drive control is performed with any of the fulfillment of B) or (C) and the fulfillment of the condition (A) or (B) or (C) as a necessary condition for the execution.

If the throttle valve is kept at a specific opening for a long period of time, the above-mentioned uneven wear is likely to occur. In this regard, if the drive control of the actuator is performed when the condition (A) is satisfied, the drive control can be performed in a situation where such uneven wear is likely to occur.

On the other hand, depending on the condition of use of the internal combustion engine, etc.,
The frequency of use of the throttle valve may be relatively high in a specific opening range, and the uneven wear may be concentrated on a portion corresponding to the specific opening range. In addition, the influence of the drive control of the actuator for suppressing uneven wear on the engine operation such as the fluctuation of the engine output also differs depending on the opening degree of the throttle valve. That point,
Assuming that the condition (B) is the execution condition, the drive control is executed when the target opening of the throttle valve is within the specific opening range as described above. For this reason, the drive control can be performed by selecting a specific opening range in which uneven wear easily occurs or a specific opening range in which the execution has a small effect on the operation of the internal combustion engine.

Further, if the drive control of the actuator is executed, the actual opening of the throttle valve fluctuates, which may cause a fluctuation in the engine output. In this regard, if the condition (C) is set as the execution condition, the drive control is executed when the change in the actual opening of the throttle valve has a relatively small effect on the operation of the internal combustion engine. For this reason, the drive control can be executed when fluctuations in the engine output can be suppressed and adverse effects on the operation of the internal combustion engine can be suppressed.

(Claim 5) According to a fifth aspect of the present invention, there is provided the throttle valve opening control device according to any one of the first to third aspects, wherein the following conditions (A) to (C) are satisfied: (A) the set target opening is kept constant for a predetermined period; (B) the set target opening is within a predetermined range; (C) the set target opening Wherein the drive control means is configured to execute drive control of the actuator when at least two logical ANDs of the engine output fluctuation amount with respect to the unit fluctuation amount of the engine output are equal to or less than a predetermined value are satisfied. It is.

According to the above configuration, the above conditions (A) to (A)
When at least two or more logical products of (C) are satisfied, the drive control of the actuator described above is executed. That is, the logical product of the conditions (A) and (B) is satisfied, the logical product of the conditions (A) and (C) is satisfied, and the condition (B) is satisfied.
AND of (C) and the above conditions (A) to
(C) The above drive control is performed with one of the conditions of all logical products being a necessary condition for execution.

Assuming that the condition (A) is satisfied as a necessary condition for the execution of the drive control, the drive is controlled only when the target opening is kept constant for a predetermined period and uneven wear is likely to occur. Control is executed. For this reason, it is possible to suitably suppress the occurrence of uneven wear while minimizing the influence on the internal combustion engine such as the fluctuation of the engine output.

If it is assumed that the condition (B) is satisfied, it is necessary to satisfy the requirement that uneven wear is likely to occur, or that the drive control has a small effect on the operation of the internal combustion engine. The above drive control is executed by selecting only the opening degree range. Thereby, uneven wear can be suppressed in a more suitable manner such as suppression of the influence on the operation of the internal combustion engine and improvement of the suppression efficiency.

If the condition (C) is fulfilled as a necessary condition for the execution, the fluctuation of the engine output according to the fluctuation of the actual opening of the throttle valve accompanying the execution of the drive control is relatively small. Only when is the above-described drive control executed. Thereby, the influence on the operation of the internal combustion engine can be more suitably suppressed while suppressing uneven wear.

According to a sixth aspect of the present invention, in the throttle valve opening control device according to the fourth or fifth aspect, the execution condition (B) is set as an execution condition of the drive control of the actuator. The drive control unit is configured to include the range of the opening in which the variation of the engine output with respect to the set unit variation of the target opening is equal to or less than a predetermined value, as the predetermined range.

In the above configuration, the drive control is executed by selecting a time when the fluctuation of the engine output caused by the fluctuation of the actual opening of the throttle valve accompanying the execution is in a relatively small range of the opening. Therefore, the occurrence of uneven wear can be suitably suppressed while minimizing the influence on the operation of the internal combustion engine.

According to a seventh aspect of the present invention, in the throttle valve opening control device according to the fourth or fifth aspect, the execution condition (B) is set as an execution condition of the drive control of the actuator. And the drive control means is configured to set the vicinity of the full opening of the throttle valve in the predetermined range.

In the above configuration, the drive control is executed in the vicinity of the full opening where the change in the intake air amount due to the change in the opening of the throttle valve is extremely small. For this reason, it is possible to suppress the fluctuation of the engine output due to the execution of the drive control and to appropriately suppress the uneven wear while suppressing the influence on the operation of the internal combustion engine.

(Claim 8) The invention according to claim 8 is provided with an actuator for opening and closing the throttle valve of the internal combustion engine, and a throttle sensor for detecting the opening of the throttle valve. In a throttle valve opening control device that drives and controls the actuator such that the opening matches a target opening set based on the engine operating state, the actual opening of the throttle valve corresponding to the fully open position of the throttle valve And a drive control means for performing drive control of the actuator so as to periodically change the degree.

The setting frequency of the fully opened position of the throttle valve tends to be higher than other opening positions, and the engine vibration at the time of the setting is large. In the degree, the uneven wear is extremely likely to occur. In this regard, in the above configuration, the actual opening of the throttle valve corresponding to such a fully open position is periodically changed, so that the occurrence of the uneven wear can be suitably suppressed. Note that, as described above, near the full opening of the throttle valve, the change in the engine output due to the change in the actual opening degree is small, so that the execution of the drive control of the actuator has a small effect on the engine operation. Therefore, according to the above configuration, it is possible to preferably suppress the occurrence of the uneven wear while suppressing the influence on the engine operation.

According to a ninth aspect of the present invention, in the throttle valve opening control device according to the eighth aspect, the amount of fluctuation of the engine output with respect to the periodic change is set to a predetermined value or less. The drive control means is configured to execute drive control of the actuator.

In the above configuration, the actual opening degree corresponding to the fully open position is changed within a range in which the fluctuation amount of the engine output is equal to or less than a predetermined value. For this reason, it is possible to both suppress the uneven wear and maintain stable operation of the engine.

According to a tenth aspect of the present invention, there is provided the throttle valve opening control device according to the eighth or ninth aspect, wherein the electronic control device for controlling the internal combustion engine has a small calculation load. The drive control means is configured to perform the periodic change.

In the above configuration, when the calculation load of the electronic control unit for operating the engine is small, the processing for changing the actual opening corresponding to the fully open position of the throttle valve is performed. For this reason, an excessive increase in the calculation load of the electronic control unit during the execution of the processing can be suitably avoided. By the way, at the time of engine idle operation, the calculation load of the electronic control unit is relatively small, which is suitable for performing the above processing. Also, when the engine is started, the calculation load of the electronic control unit is relatively small, which is preferable for performing the above processing.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment in which the present invention is applied to a throttle valve opening control device provided in an in-cylinder fuel injection type internal combustion engine will be described below. This will be described with reference to FIGS.

FIG. 1 schematically shows the structure of the opening control device. As shown in FIG. 1, the opening control device includes a throttle motor 40 for opening and closing the throttle valve 20, a throttle sensor 30 for detecting the opening of the throttle valve 20, and the like, and an electronic control device for driving and controlling the throttle motor 40. 50 and the like.

The throttle valve 20 has a valve shaft 21 rotatably supported by the intake pipe 12 of the internal combustion engine 10.
And a disk-shaped valve body 22 fixed to the valve shaft 21.

The driven gear 4 is provided at the end of the valve shaft 21.
The driven gear 42 is meshed with a drive gear 41 provided on a rotation shaft of the throttle motor 40. The valve shaft 21 is connected to the throttle motor 4 transmitted through the drive gear 41 and the driven gear 42.
It rotates with a driving force of zero.

As shown in FIG. 2, when the valve body 22 rotates together with the valve shaft 21, the throttle valve 20 is fully closed (the actual opening degree θb is indicated by a solid line in FIG. 2). It is adjusted between the actual opening degree θb ≒ “0 °”) and the fully open state indicated by the two-dot chain line (actual opening degree θb 二 “90 °”). By adjusting the opening of the throttle valve 20 in this manner, the passage cross-sectional area of the intake pipe 12 is changed, and the amount of intake air is adjusted.

In the valve shaft 21, the valve body 2
The throttle sensor 30 is provided in a portion located between the second gear 2 and the driven gear 42. FIG. 3 schematically shows the configuration of the throttle sensor 30.

The throttle sensor 30 is a well-known contact sensor, and as shown in FIG.
, A housing 310 penetrating therethrough, four detection patterns 321 to 32 connected to the electronic control unit 50 via a plurality of terminals 341 to 344
4 and a pair of contacts 331, 33 attached to a rotor (not shown) that rotates with the valve shaft 21.
2 and the like.

Of the detection patterns 321 to 324, a pair of detection patterns 321 and 322 are for detecting that the throttle valve 20 is in a fully closed state, in other words, that the internal combustion engine 10 is in an idle state. It is.
Each of these detection patterns 321 and 322 is formed of a conductor such as gold, and has a first terminal 341,
Each is electrically connected to the second terminal 342.

Further, a pair of detection patterns 323, 32 other than the one for the full-close detection among the detection patterns 321 to 324 are provided.
Numeral 4 is for detecting the opening of the throttle valve 20, and these detection patterns 323 and 324 are formed so as to form an arc around the valve shaft 21. These detection patterns 323, 32
4, one of the detection patterns 323 is formed of a conductor such as gold similarly to the other detection patterns 321 and 322, and is electrically connected to the third terminal 343. On the other hand, the other detection pattern 324 is formed of a resistor such as carbon, and its ends are electrically connected to the first terminal 341 and the fourth terminal 344, respectively.

One of the contacts 331 out of the contacts 331 and 332 changes its position with the rotation of the valve shaft 21. When the throttle valve 20 shifts to the fully closed state, it is used for detecting the fully closed state. It contacts both the detection patterns 321 and 322. Therefore, the first terminal 341 and the second terminal 342 are brought into conduction through the contact 331. The electronic control unit 50 detects that the throttle valve 20 is in the fully closed state based on the fact that the terminals 341 and 342 are in the conductive state.

When the valve shaft 21 rotates, the other of the contacts 331 and 332 is
The slider slides on the detection patterns 323 and 324 while contacting both of the detection patterns 323 and 324 for detecting the opening degree.

The first terminal 341 and the fourth terminal 3
A predetermined reference voltage is applied between 44. Therefore, the contact 3 on each of the detection patterns 323 and 324 is provided between the first terminal 341 and the third terminal 343.
The divided voltage of the reference voltage is output in accordance with the position of 32, in other words, the rotation phase of the valve shaft 21. The electronic control unit 50 controls the first terminal 341 and the third terminal 34
The rotation phase of the valve shaft 21, that is, the opening of the throttle valve 20, is detected based on the magnitude of the partial pressure output between the three.

As shown in FIG. 1, the electronic control unit 50 detects the amount of depression of the accelerator pedal 14 (accelerator opening) as a sensor for detecting the operating state of the engine in addition to the throttle sensor 30. Sensor 31 for detecting the engine speed, and a speed sensor 32 for detecting the engine speed.

The electronic control unit 50 controls each of these sensors 3
The target opening θa of the throttle valve 20 is calculated based on the accelerator opening and the engine rotation speed detected by the throttle valves 1 and 32, and the opening (actual opening θb) of the throttle valve 20 matches the target opening θa. Throttle motor 4
0 is drive-controlled. The electronic control unit 50 has a memory (not shown) for storing a control program for executing such drive control, a calculation map for calculating the target opening θa based on the accelerator opening and the engine speed, and the like. Have.

In addition to the above control, the electronic control unit 50 also detects uneven wear in the drive section of the throttle motor 40, such as the meshing portions of the gears 41 and 42, and the detection patterns 323 and 323 for detecting the opening of the throttle sensor 30. In order to suppress uneven wear at 324, when a predetermined condition is satisfied, the throttle valve 20 is set on the basis of the target opening degree θa.
Is executed to forcibly change the opening degree of the cycle.

Hereinafter, control of the opening of the throttle valve 20 by the electronic control unit 50 will be described with reference to FIGS. FIG. 5 is a flowchart showing a specific processing procedure of the opening degree control. A series of processes shown in this flowchart is executed by the electronic control unit 50 as an interrupt process at predetermined intervals.

In this series of processing, first, the target opening θa of the throttle valve 20 set based on the engine operating state such as the accelerator opening and the engine speed is read (step 100). Next, the actual opening degree θb of the throttle valve 20 is read based on the detection signal of the throttle sensor 30 (step 110).

Next, the variation Δθa when the target opening θa is periodically varied is calculated (step 120).
As shown in FIG. 4, the variation Δθa is a predetermined value θ.
0 (for example, “0 °”) as the reference, and the maximum value Δθam
It is set as a value that fluctuates with a predetermined cycle T between ax and a predetermined value θ0. Here, the maximum value Δθama
x, that is, the variation width of the variation Δθa is set to, for example, “2 °”, and the cycle T is set to, for example, “2 seconds” which is sufficiently larger than the cycle of the vibration of the internal combustion engine 10. Further, as shown in FIG. 4, the variation Δθa is set such that its temporal change has a triangular waveform.

After the variation Δθa is calculated in this way, it is determined whether or not the target opening θa is near a predetermined reference opening θc (step 130). This determination is made based on, for example, whether the following conditional expression (1) is satisfied. θc−α ≦ θa ≦ θc + α (1) In the above conditional expression (1), the reference opening θc is equal to the magnitude of the target opening θa immediately before the conditional expression (1) is satisfied. “Α” is a constant, for example, “0.5 °”
Is set to

If it is determined that the conditional expression (1) is not satisfied (step 130: NO), the current target opening θa is set as a new reference opening θc (step 130). 170).

On the other hand, if it is determined in the previous step 130 that the above-mentioned conditional expression (1) is satisfied, a predetermined period elapses from the time when the next conditional expression (1) is satisfied. (Step 13).
5). If it is determined that the predetermined period has elapsed (step 135: YES), the current target opening θ
It is determined whether or not the fluctuation amount (engine fluctuation amount) ΔET of the engine output ET with respect to the unit fluctuation amount a is equal to or smaller than a predetermined value (step 140).

FIG. 6 is a graph showing the relationship between the target opening degree θa and the engine output fluctuation amount ΔET. As shown in the figure, the engine output fluctuation amount ΔET tends to decrease as the target opening degree θa increases and approaches the full opening. This is because, as the opening degree of the throttle valve 20 becomes relatively large, the change in the intake air amount accompanying the change in the opening degree becomes smaller, and the fluctuation amount of the engine output due to the change in the intake air amount becomes smaller. is there. Also, the opening of the throttle valve 20 becomes close to full open, and the valve body 2
2 is present in the projection area of the valve shaft 21 (the area sandwiched by the two-dot chain line in FIG. 2)
The change in the intake air amount due to the change in the opening degree is further reduced.

Based on these characteristics, the electronic control unit 50 determines that the engine output fluctuation amount ΔET is equal to or less than a predetermined value when the target opening θa is equal to or greater than the predetermined determination opening θe in the determination in step 140. I try to judge. Note that the determination opening degree θe is set to an opening degree (for example, “80 °”) at which the valve body 22 of the throttle valve 20 exists in the projection area of the valve shaft 21.

In step 140, when it is determined that the engine output fluctuation amount .DELTA.ET corresponding to the current target opening .theta.a is equal to or smaller than a predetermined value, that is, it is determined that the target opening .theta.a is equal to or larger than the above-described determination opening .theta.e. In this case, the target opening θa is reset based on the following equation (2) (step 150). Target opening θa ← [current target opening θa] + variation Δθa (2) After the target opening θa is reset in this way, the throttle valve 20 detected by the throttle sensor 30
The throttle motor 40 is controlled by the electronic control unit 50 so that the actual opening degree θb of the throttle valve coincides with the reset target opening degree θa.
Is driven (step 160). In this drive control, even if the reset target opening degree θa exceeds the full opening (90 °), the target opening degree θa
And the actual opening degree θb coincide with each other.
Is drive-controlled.

On the other hand, after the processing of the previous step 170 is executed, or when it is determined in step 135 that the predetermined period has not elapsed (step 135: N
O), and when it is determined that the engine output fluctuation amount ΔET corresponding to the current target opening θa exceeds a predetermined value (step 140: NO), the target opening θa is reset (step 150). Step 16 is performed without performing
0 processing is performed. That is, in this case, the drive of the throttle motor 40 is controlled in accordance with the target opening degree θa based on the engine operating state read in the previous step 100.

After the drive of the throttle motor 40 is controlled in step 160 in this manner, this series of processing is temporarily terminated. FIG. 7 is a timing chart showing an example of a change mode of the target opening degree θa based on the above series of processing.

As shown in the figure, when the target opening θa is kept constant within the range not less than the judgment opening θe, when the conditional expression (1) is satisfied (at timing t).
After a lapse of a predetermined period from 1) (timing t2), thereafter, the target opening degree θa is reset based on the fluctuation amount Δθa. For this reason, the target opening degree θa based on the engine operating state, such as the accelerator opening degree and the engine rotation speed.
(See the two-dot chain line in the figure) is kept constant, the opening of the throttle valve 20 periodically fluctuates in accordance with the reset target opening θa.

Therefore, the respective meshing portions of the driving gear 41 and the driven gear 42 always change, and the positions of the contacts 332 on the respective detection patterns 323 and 324 always change. As a result, the internal combustion engine 1
Even when the vibration of 0 is transmitted, the local wear of these meshing portions and the respective detection patterns 323 and 324 is suppressed.

On the condition that the target opening θa is equal to or larger than the judgment opening θe and the engine output variation ΔET corresponding to the target opening θa is equal to or smaller than a predetermined value, the throttle valve 20
The opening of the throttle valve 20 changes within the range from the above-mentioned determination opening θe to the full opening, and the fluctuation of the engine output due to the periodic fluctuation is kept small. Will be able to Therefore, the fluctuation of the engine output due to the periodic fluctuation of the opening degree of the throttle valve 20 is suppressed, and the adverse effect on the operation of the internal combustion engine 10 is suppressed.

On the other hand, when the target opening degree θa set based on the engine operating state changes and the above-mentioned conditional expression (1) is not satisfied (timing t3 in FIG. 7), the target opening degree θa based on the variation Δθa is obtained. Will not be reset. Accordingly, thereafter, the drive of the throttle motor 40 is controlled so that the opening of the throttle valve 20 matches the target opening θa based on the engine operating state.

According to the above-described embodiment, the following effects can be obtained. (1) Even if the target opening degree θa based on the engine operating state, such as the accelerator opening degree and the engine rotation speed, is kept constant, the above-mentioned drive gear is controlled while suppressing the adverse effect on the operation of the internal combustion engine 10. 41 and the driven gear 42, and the respective detection patterns 323, 3 of the throttle sensor 30.
24, the occurrence of uneven wear can be suppressed.

(2) When the opening degree of the throttle valve 20 is changed periodically, the execution condition is that the target opening degree θa based on the engine operating state is kept constant for a predetermined period. Gear 41 and driven gear 4
The opening degree of the throttle valve 20 is periodically changed only in a situation where uneven wear is likely to occur in each meshing portion 2 and each detection pattern 323, 324 of the throttle sensor 30. , Internal combustion engine 10
The adverse effect on the operation of the vehicle can be suppressed as much as possible.

[Second Embodiment] Next, a second embodiment of the present invention will be described.
This embodiment will be described focusing on the differences from the first embodiment. Note that, in each of the following embodiments, a description of the same configuration and the like as in the above embodiment will be omitted.

Generally, in a cylinder fuel injection type internal combustion engine,
When the combustion mode is switched to lean combustion, the engine output is basically adjusted by the fuel injection amount,
The opening of the throttle valve is maintained at an opening near the full opening. Therefore, the driving gear 4 as described above is used.
Uneven wear at each meshing portion of the first and driven gears 42 and at each of the detection patterns 323 and 324 of the throttle sensor 30 is particularly likely to occur when the opening of the throttle valve 20 is held close to full open during lean burn.

Therefore, in this embodiment, when the target opening θa is an opening near the full opening, the opening of the throttle valve 20 is periodically changed near the full opening. Hereinafter, a specific processing procedure of the opening degree control in the present embodiment will be described with reference to a flowchart shown in FIG. A series of processes shown in this flowchart is executed by the electronic control unit 50 as an interrupt process at predetermined intervals. Note that among the steps shown in FIG. 8, steps denoted by the same reference numerals as those in the flowchart of FIG.

In this series of processing, step 100
After execution of the processes of to 120, it is determined whether or not the target opening θa based on the engine operating state is larger than the predetermined opening θ1 (step 132). The predetermined opening θ1 is for determining whether or not the target opening θa is an opening near the full opening, and is set to, for example, “88 °” which is slightly smaller than the full opening (“90 °”). Have been.

If it is determined that the target opening θa is larger than the predetermined opening θ1 (step 132: YES), the target opening θa is reset based on the following equation (3) (step 132). 155). Target opening degree θa ← predetermined opening degree θ1 + variation amount Δθa (3) After the target opening degree θa is thus reset, the throttle valve 20 detected by the throttle sensor 30
The throttle motor 40 is controlled by the electronic control unit 50 so that the actual opening degree θb of the throttle valve coincides with the reset target opening degree θa.
Is driven (step 160).

Here, as for the target opening θa reset on the basis of the arithmetic expression (3), the predetermined opening θ1 is set to “88 °”, and the maximum value Δθamax is set to “2 °”. Therefore, the period fluctuates in the range of “88 ° to 90 °”. For this reason, even if the target opening θa based on the engine operating state such as the accelerator opening and the engine rotation speed is kept constant, the opening of the throttle valve 20 is adjusted to the fluctuation of the reset target opening θa. And fluctuates periodically. Therefore, the respective meshing portions of the driving gear 41 and the driven gear 42 always change,
In addition, the position of the contact 332 on each of the detection patterns 323 and 324 constantly changes. As a result, even when the vibration of the internal combustion engine 10 is transmitted, the local wear of these meshing portions and the detection patterns 323 and 324 is suppressed.

Further, under the condition that the target opening degree θa is close to full opening, the opening degree of the throttle valve 20 is made to fluctuate periodically near full opening (“88 ° to 90 °”). Fluctuations in the engine output due to the periodic fluctuations can be kept small. Therefore, throttle valve 2
Fluctuations in the engine output due to the periodic fluctuation of the opening degree of 0 are suppressed, and adverse effects on the operation of the internal combustion engine 10 are suppressed.

On the other hand, if it is determined in step 132 that the target opening θa is equal to or smaller than the predetermined opening θ1 (step 132: NO), the target opening θa is reset (step 155). The processing of step 160 is performed without being performed. That is, in this case, the drive of the throttle motor 40 is controlled in accordance with the target opening degree θa based on the engine operating state read in the previous step 100.

After the drive of the throttle motor 40 is controlled in step 160 in this way, this series of processing is temporarily terminated. Also in the present embodiment described above, the same operation and effect as the above (1) shown in the first embodiment can be obtained.

The first and second embodiments of the present invention explained above
The embodiment can be implemented by changing its configuration as follows. In the first embodiment, (a) the engine output fluctuation amount ΔET corresponding to the target opening degree θa is equal to or less than a predetermined value, and
(B) The opening degree of the throttle valve 20 is made to periodically fluctuate on condition that the target opening degree θa is kept constant for a predetermined period. For example, whether the condition (b) is satisfied or not Regardless, the opening degree of the throttle valve 20 may be periodically changed whenever the above condition (a) is satisfied.

In the second embodiment, the opening degree of the throttle valve 20 is made to fluctuate periodically on condition that the target opening degree θa is close to the fully opened state. For example, the target opening degree θa The opening degree of the throttle valve 20 may be periodically changed on the condition that the opening degree is maintained at the opening degree near the full opening for a predetermined period.

In this case, for example, after a positive determination is made in step 132 shown in FIG. 8, it is determined whether or not a predetermined period has elapsed since the target opening θa exceeded the predetermined opening θ1. Only when it is determined that the predetermined period has elapsed, the target opening degree θa is reset in step 155.

In this way, the throttle valve 20 can be used only in a situation where uneven wear tends to occur in each meshing portion of the driving gear 41 and the driven gear 42 and in each of the detection patterns 323 and 324 of the throttle sensor 30. By periodically varying the opening, adverse effects on the operation of the internal combustion engine, such as variations in engine output, can be suppressed as much as possible.

As described above, as the target opening θa becomes smaller, the engine output variation ΔE corresponding to the target opening θa becomes smaller.
T increases (see FIG. 6). Therefore, in each of the above embodiments, the variation width of the variation amount Δθa is set to a constant value (“2 °”). However, the variation width is reduced, for example, the smaller the target opening θa, the smaller the variation width. May be variably set based on the target opening degree θa. In this way, it is possible to suppress the occurrence of uneven wear while further suitably suppressing the fluctuation of the engine output due to the periodic fluctuation of the opening of the throttle valve 20.
Similarly, the period T can be variably set based on the target opening degree θa.

In each of the above embodiments, the fluctuation amount of the engine output is estimated from the fluctuation of the engine rotation speed and the like, and the fluctuation width and cycle T of the fluctuation amount Δθa are appropriately changed according to the fluctuation amount of the engine output. It may be.

[Third Embodiment] Next, a third embodiment of the present invention will be described.
This embodiment will be described focusing on differences from the above embodiments.

The frequency of setting of the fully open position of the throttle valve tends to be higher than other open positions, and the engine vibration at the time of the setting is large. With the degree of opening, the uneven wear is extremely likely to occur. Thus, in the present embodiment, the occurrence of such uneven wear is suppressed by periodically changing the actual opening of the throttle valve corresponding to such a fully open position.

Hereinafter, a specific processing procedure of the opening control in the present embodiment will be described with reference to a flowchart shown in FIG. A series of processes shown in this flowchart is executed by the electronic control unit 50 as an interrupt process at predetermined intervals.

In this series of processing, first, it is determined whether or not the condition for changing the throttle fully open position WOT indicating the actual opening of the throttle valve 20 corresponding to the above fully open position is satisfied (S200). In the present embodiment, the electronic control device 50
It is determined that the change condition is satisfied when the calculation load is immediately after the start of the engine.

In the present embodiment, when the calculated value of the target opening degree θa calculated according to the engine operating state exceeds the throttle fully open position WOT, the same fully open position WOT is used.
Is used as the final target opening degree θa to drive the throttle motor 40. That is, the throttle fully open position WOT is used as an upper limit guard value of the target opening degree θa. Therefore, the value of the full open position WOT is a parameter that defines the actual opening of the throttle valve 20 corresponding to the full open position.

If the change condition is satisfied (S20)
0: YES), the electronic control unit 50 proceeds to step 21
At 0, it is determined whether or not the value of the counter Cwhite exceeds a predetermined value.

If the target opening degree θa is equal to or greater than the full open position WOT during the execution of this processing, the value of the counter Cwot is incremented (S).
260, 270). When the fully open position WOT is updated (S220), the value Cwot is cleared. Therefore, the value of the counter Cwot is calculated based on the total amount of time during which the target opening degree θa is set to the full open position WOT after the previous update of the throttle full open position WOT, that is, the total use time of the throttle valve 20 at the current full open position WOT. Equivalent to.

The electronic control unit 50 operates the counter Cw
If the value of ot exceeds a predetermined value (S210: YE
S), the value of the fully open position WOT is updated (S2).
20-250). That is, in the present embodiment, the total use of the throttle valve 20 at the current fully open position WOT is performed in a situation where the calculation load of the electronic control device 50 is small, such as when the engine is started, at a low rotation speed, or during steady running. When the time exceeds the predetermined time, the fully open position WOT is updated. The updating process is performed as follows.

In the present embodiment, the value of the fully open position WOT is incremented by a predetermined value α each time it is updated (S220). However, the upper limit WO
Tmx is defined. When the value of the fully open position WOT exceeds the upper limit value WOTmx (S230: YES), the value of the fully open position WOT is set to the initial value WOTi (S240). Therefore, in the present embodiment, the value of the fully open position WOT largely depends on the usage time of the throttle valve 20 at the same value WOT, as shown in FIG.
In a manner as exemplified in FIG. As a result, the correspondence between the calculated value of the target opening θa calculated according to the engine operating state and the final value finally used for the throttle opening control is as shown in FIG. It changes according to the set value of the fully open position WOT.

By periodically updating the fully open position WOT as described above, the actual opening of the throttle valve 20 corresponding to the fully open position is prevented from being kept constant for a long period of time, and the uneven wear is prevented. Is suppressed.

In the present embodiment, the initial value WOTi and the upper limit value WOT that define the possible range of the fully open position WOT are described.
mx is set so that the fluctuation of the engine output due to the change of the fully open position WOT in this process is kept within a predetermined range in which the engine operation can be suitably maintained. For example, their values W
If both the Oti and WOTmx are set to the opening degree in the projection area of the valve shaft 21 by the valve body 22 as illustrated in FIG. 2, regardless of the change of the fully open position WOT,
The change in the amount of intake air when the full open position WOT is used is further reduced. As a result, it is possible to appropriately suppress a change in the engine maximum output due to the change in the fully open position WOT.

According to the above-described embodiment, the following effects can be obtained. (1) In the present embodiment, since the actual opening of the throttle valve 20 corresponding to the fully open position is periodically changed, even if the frequency at which the target opening θa is held at the fully open position is high, the throttle valve 20 is not changed. The frequency at which the actual opening is maintained at a constant opening can be kept relatively low. For this reason, the occurrence of uneven wear in each meshing portion of the drive gear 41 and the driven gear 42 and in each of the detection patterns 323 and 324 of the throttle sensor 30 can be effectively suppressed. Further, since only the fully open position where the change in engine output is relatively small due to the change in the opening degree of the throttle valve 20 is changed, the influence of such control for suppressing uneven wear on the engine operation can be minimized.

(2) In this embodiment, the electronic control unit 50
At the start of the engine with a small calculation load, the fully open position WOT
The processing related to the periodic change of is performed. For this reason, an excessive increase in the calculation load of the electronic control unit 50 during the execution of the processing can be suitably avoided.

(3) In the present embodiment, the current fully open position W
When the total use time of the throttle valve 20 in the OT exceeds a predetermined time, the value of the fully open position WOT is updated. For this reason, the actual opening of the throttle valve 20 corresponding to the fully open position can be changed at an appropriate time, and the occurrence of the uneven wear can be suppressed more appropriately.

(4) In the present embodiment, the range of the change of the actual opening corresponding to the fully open position is set so that the change amount of the engine output accompanying the change is within a predetermined value.
For this reason, a change in the engine maximum output due to a change in the actual opening corresponding to the full-open position is also suitably suppressed.

The above-described embodiment can be modified and implemented as follows. In the above embodiment, the throttle valve 20 at the time of (a) engine start and (b) the current fully open position WOT is used.
When the total use time exceeds a predetermined time, the fully open position W
Although the OT is changed, the fully open position WOT may be changed depending on whether only (a) or (b) is satisfied.

If the change of the fully open position WOT is performed not only when the engine is started but also when the calculation load of the electronic control device 50 is small, for example, during idling operation, the calculation by the electronic control device 50 at the time of the change is performed. The occurrence of uneven wear can be suppressed by suitably avoiding an excessive increase in load.

In the above embodiment, the time when the target opening degree θa of the throttle valve 20 is set at the full open position WOT is actually measured to determine the update timing of the full open position WOT. The renewal timing may be determined from the number of engine starts, the engine operation time, and the like.
Even in such a case, it is possible to roughly estimate the time during which the target opening degree θa is set at the fully open position WOT, and it is possible to update the fully open position WOT at an appropriate cycle.

In the above embodiment, the fully open position WOT is periodically updated in the mode illustrated in FIG. 10, but the update mode may be arbitrarily changed. In short, if the full opening position WOT is periodically updated so that the actual opening of the throttle valve 20 corresponding to the full opening position of the target opening θa is not kept constant, the occurrence of the uneven wear can be suppressed. it can.

In each of the embodiments described above, the throttle valve 2 provided in the in-cylinder fuel injection type internal combustion engine is used.
Although the opening degree control device of 0 has been illustrated, the present invention can also be applied to a device for controlling the opening degree of a throttle valve provided in, for example, an intake port injection type internal combustion engine.

The above embodiments and their modifications include the following technical ideas. (A) The throttle valve opening control device according to any one of claims 8 to 10, wherein the drive control means performs the periodic change when the internal combustion engine is started.

(B) The throttle valve opening control device according to any one of claims 8 to 10, wherein the drive control means performs the periodic change during idle operation of the internal combustion engine.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a throttle valve opening control device.

FIG. 2 is a sectional view showing a sectional structure of an intake pipe and a throttle valve.

FIG. 3 is a schematic configuration diagram of a throttle sensor.

FIG. 4 is a timing chart showing a change in a throttle valve opening variation amount.

FIG. 5 is a flowchart showing a procedure for controlling the opening of a throttle valve according to the first embodiment;

FIG. 6 is a graph showing a relationship between a target opening of a throttle valve and an engine output fluctuation amount.

FIG. 7 is a timing chart showing a change in the target opening of the throttle valve.

FIG. 8 is a flowchart showing a throttle valve opening control procedure according to the second embodiment;

FIG. 9 is a flowchart illustrating a change control procedure of a fully open position according to the third embodiment.

FIG. 10 is a time chart showing a transition of a throttle fully open position.

FIG. 11 is a graph showing the correspondence between the calculated value of the target value of the throttle valve and the final value.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 12 ... Intake pipe, 20 ... Throttle valve, 21 ... Valve shaft, 22 ... Valve body, 30 ...
Throttle sensor, 31 Accelerator sensor, 32 Rotation speed sensor, 40 Throttle motor, 41 Drive gear, 42 Driven gear, 50 Electronic control unit, 310 Housing, 341-344 Terminal, 321-324 Detection Pattern, 331, 332...

Continued on the front page (72) Inventor Naoto Kushi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd. F-term (reference) 3G065 CA27 DA05 DA06 DA15 EA08 FA02 FA08 GA10 GA41 GA46 HA06 HA12 HA21 HA22 JA04 JA09 JA11 KA02 KA35 3G301 JA16 KA09 LA03 LB01 LC03 NA06 NA08 NB03 NB12 NB15 NC02 ND02 NE03 NE08 NE23 PA11A PA11Z PE01Z PF03Z

Claims (10)

[Claims] 1. An actuator for opening and closing a throttle valve of an internal combustion engine, and a throttle sensor for detecting an opening of the throttle valve, wherein the detected opening of the throttle valve is set based on an engine operating state. In the throttle valve opening control device that drives and controls the actuator so as to match the target opening, when the engine operation state is a specific operation state, the actual opening degree of the throttle in the specific operation state is always An opening control device for a throttle valve, comprising: a drive control unit that drives and controls the actuator so as to suppress the opening from being constant. 2. An actuator for opening and closing a throttle valve of an internal combustion engine, and a throttle sensor for detecting an opening of the throttle valve, wherein the detected opening of the throttle valve is set based on an engine operating state. An opening control device for a throttle valve that drives and controls the actuator so as to coincide with a target opening, wherein when the engine operation state is a specific operation state, the actual opening degree of the throttle valve is based on the target opening degree. And a drive control means for controlling the drive of the actuator so as to vary periodically. 3. The drive control means variably sets at least one of a fluctuation width and a period when the actual opening degree of the throttle valve is periodically fluctuated, based on the magnitude of the set target opening degree. 3. The throttle valve opening control device according to claim 2, wherein the drive control of the actuator is performed. 4. The driving control means according to claim 1, wherein:
(C), that is, (A) the set target opening is kept constant for a predetermined period, (B) the set target opening is within a predetermined range, (C) the The drive control of the actuator is performed when at least one of the following conditions is satisfied: a variation amount of the engine output with respect to a unit variation amount of the set target opening is equal to or less than a predetermined value. 3. The throttle valve opening control device according to claim 1. 5. The driving control means according to claim 1, wherein:
(C), that is, (A) the set target opening is kept constant for a predetermined period, (B) the set target opening is within a predetermined range, (C) the The drive control of the actuator is performed when at least two logical ANDs of a variation amount of the engine output with respect to a unit variation amount of the set target opening degree being equal to or less than a predetermined value are satisfied. The throttle valve opening control device according to any one of the above. 6. The drive control means includes the condition (B) as an execution condition of drive control of the actuator, and a variation of an engine output with respect to a unit variation of the set target opening is equal to or less than a predetermined value. The throttle valve opening control device according to claim 4 or 5, wherein a range of the opening degree is set to the predetermined range. 7. The drive control device according to claim 4, wherein the drive control means includes the condition (B) as an execution condition of the drive control of the actuator, and sets the predetermined range near the fully open state of the throttle valve. Throttle valve opening control device. 8. An actuator for opening and closing a throttle valve of an internal combustion engine, and a throttle sensor for detecting an opening of the throttle valve, wherein the detected opening of the throttle valve is set based on an engine operating state. An opening control device for a throttle valve that drives and controls the actuator so as to coincide with a target opening, wherein the actual opening of the throttle valve corresponding to a fully open position of the throttle valve is periodically changed. An opening control device for a throttle valve, comprising a drive control means for performing drive control. 9. The throttle valve opening control as set forth in claim 8, wherein said drive control means executes drive control of said actuator so that an amount of change in engine output with respect to said periodic change is equal to or less than a predetermined value. apparatus. 10. The throttle valve opening control according to claim 8, wherein said drive control means performs said periodic change when a calculation load of an electronic control device for controlling said internal combustion engine is small. apparatus.