JPH10196430A - Controller of electronically controlled throttle valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase or decrease a flow rate of suction air precisely in accordance with load fluctuation and suppress the fluctuation in engine rotation with high precision so as to improve engine operation performance by controlling a degree of opening of an electronically controlled throttle valve to change a flow rate of suction air and correcting nonlinear relations between a degree of opening of the throttle valve and a flow rate of suction air. SOLUTION: It is judged whether load fluctuation occurs or not based on a change- over condition to ON signals of an air conditioner switch, a power steering switch, and an electric load switch. When it is judged that the load fluctuation occurs (S1), an amount of change Q2 of the flow rate of suction air necessary for suppressing rotation fluctuation is determined (S2). Current degree of opening of a throttle valve is detected based on a signal from a throttle sensor (S3). Current flow rate of suction air Q1 and the amount of change Q2 of the flow rate of suction air which is derived from the load fluctuation and is necessary for suppressing rotation fluctuation are summed to obtain a control target Q3 (=Q1 +Q2 ) (S5). A drive signal is sent to an actuator so that a target degree of opening of the throttle valve can be detected based on the control target Q3 to control a degree of opening of the throttle valve (S6).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronically controlled throttle valve interposed in an intake passage of an internal combustion engine (an actuator such as an electric motor so that the opening can be adjusted independently of a driver's accelerator operation). And a device for controlling a valve element that drives the valve element.

[0002]

2. Description of the Related Art In a conventional internal combustion engine provided with a throttle valve (intake throttle valve) of an electronic control type (hereinafter, also simply referred to as an electronic control type), for example, during normal idle operation, the engine speed is set at a target value. Feedback control of the opening degree TVO of the electronically controlled throttle valve so as to reach the engine speed {so-called idle speed control (ISC control)}
I am trying to do it.

[0003] During idle operation in which such feedback control (ISC control) is performed, for example, when an air conditioner, an electric load, or the like is turned on / off and a load fluctuation occurs, the load fluctuation is caused. In order to suppress the engine rotation fluctuation, the throttle valve opening TVO is steppedly increased or decreased by a fixed amount in order to increase or decrease the intake air flow rate by a fixed amount according to the magnitude of the load fluctuation.

[0004]

However, the relationship between the throttle valve opening TVO and the intake air flow rate Q is non-linear as shown by the solid line in FIG. Is different from the throttle valve opening TVO at the start of the step control, even if the throttle valve opening TVO is changed by a certain amount from the throttle valve opening TVO at the start of the step control, the intake air amount changed by this changes. If a constant throttle valve opening TVO corresponding to a constant intake air flow rate Q is increased or decreased stepwise as in the prior art, ON / OFF of an air conditioner, an electric load, etc.
There is a concern that the intake air flow rate cannot be accurately increased or decreased in accordance with the load fluctuations caused by the switching, thereby causing a decrease in engine speed or a so-called high idle, thereby reducing engine operability and the like.

[0005] That is, conventionally, in consideration of, for example, compatibility between quality assurance and cost reduction, etc., by detecting the intake air flow rate at points A and B in FIG. The quality of the manufacturing quality is inspected. In the actual opening control of the throttle valve, the linear characteristics (= ΔQ / ΔTV) obtained by learning the points A and B are used.
O). Therefore, the amount of change in the throttle valve opening TVO required to change the intake air flow rate by a constant amount has always been constant. However, in practice, as shown by the solid line in FIG.
Since the relationship between VO and the intake air flow rate Q is nonlinear, the throttle valve opening TVO at the start of the step control (before the change)
Is plotted on the abscissa, and the amount of change ΔQ in the intake air flow rate when the throttle valve opening TVO (α) is changed by a fixed amount is represented on the ordinate, as shown in FIG. When opening TVO is different, even by changing the predetermined amount the throttle valve opening TVO (alpha), the amount of intake air is changed by this is that the variations in the target change amount Q _i, the above-described i than This has led to fears of reducing the engine operability and the like.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and in an electronic control type throttle valve in which the opening degree is controlled to change the intake air flow rate, an electronic control type throttle valve is provided with a throttle valve opening degree and an intake air flow rate. An electronic control system that can correct the non-linear relationship, thereby increasing / decreasing the intake air flow rate accurately according to load fluctuations, and suppressing engine rotation fluctuations etc. with high accuracy and improving engine operability etc. An object of the present invention is to provide a control device for a throttle valve.

[0007]

Therefore, in the electronic throttle control device according to the first aspect of the present invention, the present throttle valve opening is detected as shown in FIG. A throttle valve opening detecting means, an intake air flow detecting means for detecting a current intake air flow based on a current throttle valve opening in consideration of a non-linear relationship between the throttle valve opening and the intake air flow, and a load fluctuation. Intake air flow rate change amount setting means for setting a change amount of the intake air flow rate required in accordance with: current intake air flow rate detected by the intake air flow rate detecting means; and the intake air flow rate change amount setting means. The target intake air flow rate setting means for setting the target intake air flow rate based on the intake air flow rate change amount set by, and a nonlinear relationship between the throttle valve opening and the intake air flow rate are taken into consideration. Target throttle valve opening setting means for setting a target throttle valve opening based on the target intake air flow rate set by the target intake air flow setting means; and setting the target throttle valve opening when the load changes. Throttle valve control means for controlling the throttle valve via the actuator to the target throttle valve opening set by the means.

In the control apparatus for an electronically controlled throttle valve according to the second aspect of the present invention, as shown in FIG. 2, the required change amount of the intake air flow rate is set according to the load fluctuation. Intake air flow rate change amount setting means, and a throttle valve opening degree based on the intake air flow rate change amount set by the intake air flow rate change amount setting means according to a linear relationship between a predetermined throttle valve opening and intake air flow rate. Throttle valve opening change amount setting means for setting the change amount, throttle valve opening degree detecting means for detecting the current throttle valve opening degree,
The correction coefficient set based on the current throttle valve opening and the non-linear relationship between the throttle valve opening and the intake air flow rate allows the throttle valve opening change set by the throttle valve opening change setting means to be set. Correction means for correcting the amount, and throttle valve opening change control means for changing the current throttle valve opening via an actuator by an amount of change in the throttle valve opening corrected by the correction means when there is a load change. And was comprised.

According to the third aspect of the present invention, the correction coefficient is set based on a variation characteristic of a change amount of the intake air flow with respect to the throttle valve opening before the change when the throttle valve opening is changed by a predetermined amount. Configuration.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
Description will be given based on the attached drawings. In the first embodiment of the present invention, as shown in FIG. 3, air is supplied to the engine 1 from an air cleaner (not shown) through an intake duct 2, a throttle valve (intake throttle valve) 3, and an intake manifold 5. Inhaled. In the present embodiment, the opening of the throttle valve 3 for adjusting the output torque (engine intake air flow rate or intake resistance) of the engine 1 can be controlled independently of the driver's accelerator pedal operation. , A throttle actuator 4 (for example, an electric motor) is provided. The drive of the throttle actuator 4 is controlled by a signal from a control unit 50 described later. Also, the throttle valve 3
A throttle sensor 7 is provided as throttle valve opening detecting means for detecting the actual throttle valve opening TVO.

Each branch of the intake manifold 5 is provided with a fuel injection valve 6 for each cylinder. The fuel injection valve 6 is an electromagnetic fuel injection valve that is energized by a solenoid to open, and is de-energized to close the valve. The fuel injection valve 6 is energized by a drive pulse signal transmitted from a control unit 50 described later and opens. Then, a predetermined amount of fuel which is fed from a fuel pump (not shown) and adjusted to a predetermined pressure by a pressure regulator (not shown) is supplied to the engine 1 by a predetermined amount.

An ignition plug (not shown) is provided in each combustion chamber of the engine 1 so that the air-fuel mixture is ignited by spark ignition. The ignition plug is stored in advance in the ROM of the control unit 50 based on the fuel injection amount (fuel injection drive pulse width) and the engine speed N, for example.
It is ignited at the ignition timing set and stored in the memory.

By the way, the control unit 50
The microcomputer includes a microcomputer including a CPU, a ROM, a RAM, an A / D converter, an input / output interface, a timer, and the like. The control unit 50 receives input signals from various sensors. As the various sensors, for example, a crank angle sensor 8 is provided on the crankshaft or camshaft of the engine 1 and counts a crank unit angle signal output from the crank angle sensor 8 in synchronization with the engine rotation for a certain period of time. Alternatively, the engine rotation speed N is detected by measuring the cycle of the crank reference angle signal.

Further, a water temperature sensor 9 for detecting the engine temperature is provided facing the cooling jacket of the engine 1, and the engine water temperature T
w can be detected. An accelerator switch (not shown) is provided with an idle switch 10 for detecting a driver's fully closed accelerator pedal state (idle state), and an idle signal is input to the control unit 50.

Then, in the control unit 50,
Based on input signals from various sensors, the throttle valve is controlled via the actuator 4 or the like during idle operation as described below. That is, first,
The vehicle speed from the throttle sensor 7, the idle switch 10, a vehicle speed sensor (not shown) or the like, or the engine speed N
When it is determined that the engine 1 is in the idling operation state based on the above, based on the output signal of the water temperature (Tw) sensor 9, referring to a water temperature map or the like stored in the control unit 50 in advance, Search for the target idle speed.

Next, an intake air flow rate Q (or an opening TVO of the throttle valve 3) necessary for operating the engine 1 at the target idle speed is searched with reference to a map or the like.
Then, a drive signal is sent to the actuator 4 so as to obtain the searched opening degree TVO, and the throttle valve 3
To control the opening. Further, the actual engine speed N is detected via the crank angle sensor 8 and the actual engine speed N is detected.
However, based on the deviation between the actual engine speed N and the target idle speed, the opening degree of the throttle valve 3 is controlled via the actuator 4 by, for example, proportional integral control so that the target idle speed becomes the target idle speed. Perform feedback control.

Thus, during the idling operation, the rotational speed of the engine 1 is accurately controlled to the target idle rotational speed. In the state where the target idle rotation speed is controlled as described above, the auxiliary equipment {air conditioner (A / C), power steering (P / S), alternator, etc.}
Will be described with reference to a flowchart shown in FIG. 4 when throttle operation is performed and load fluctuation (load increase side) occurs. The present invention (the invention according to claim 1)
The functions of the intake air flow rate detection means, intake air flow rate change amount setting means, target intake air flow rate setting means, target throttle valve opening degree setting means, throttle valve control means according to
The control unit 50 that executes the flow of FIGS. 4 and 7 described below is provided as software.

First, a step (shown as S in the figure).
In the following (1), the operation of the auxiliary equipment is performed based on the switching state of the air conditioner switch 11, the power steering switch 12, the electric load (hot wire defogger, headlight, electric fan, etc.) switch 13, etc. to the ON signal, and the like. It is determined whether or not a change in the required intake air flow rate (increase side) and, consequently, a load change (load increase side) occurs. If it is determined that a load change occurs, the process proceeds to step 2.

In step 2, it is necessary to suppress the rotation fluctuation based on the combination state of the input auxiliary equipment ON signals and the like (that is, based on the magnitude of the load fluctuation that will occur). determining the change amount Q ₂ of Do intake air flow rate. In other words, according to the operating state of the air conditioner, power steering, and electric load (hot wire defogger, headlight, electric fan, etc.), the required intake air flow rate for each preset load is searched, and these are summed up to obtain the required intake air flow. determining the variation Q ₂ of the air flow.

In the next step 3, the current actual slot is
Torque valve opening TVO₁Is the signal from the throttle sensor 7.
Detect based on Then, in step 4, the current
Actual (before change) throttle valve opening TVO ₁Based on
At this time, referring to the table of FIG.₁
Is detected. In step 5, the current value obtained in step 4
Intake air flow rate Q₁And the load fluctuation obtained in step 2
Change in intake air flow required to suppress rotational fluctuations caused by
Q_TwoAnd the control target Q_Three(= Q₁+ Q_Two)
Ask.

In step 6, the control target Q ₃ (= Q ₁ +
Based on Q ₂ ), the target throttle valve opening TVO ₂ is detected with reference to the table of FIG. And step 7
In, so that the target throttle valve opening TVO ₂ is obtained,
A drive signal is sent to the actuator 4 to control the opening of the throttle valve 3, and the flow ends.

In the state where the auxiliary equipment (air conditioner, power steering, alternator, etc.) is feedback-controlled to the target idle rotation speed while the auxiliary equipment (air conditioning, power steering, alternator, etc.) is not operated, When a load change (load reduction side) occurs, the following control is performed according to the flowchart of FIG. In other words, in step 10, based on the switching state of the air conditioner switch 11, the power steering switch 12, the electric load (hot wire defogger, headlight, electric fan, etc.) switch 13, etc., from the ON to OFF signal, the operation of the accessories is performed. It is determined whether or not a change (decrease) in the accompanying required intake air flow rate and, consequently, a load fluctuation (load reduction side) occurs. If it is determined that a load fluctuation occurs, the process proceeds to step 20.

In step 20, based on the combination of the input ON → OFF signals of the auxiliary devices (that is, based on the magnitude of the load fluctuation that may occur), it is necessary to suppress the rotation fluctuation. Change Q of intake air flow rate
₂ Determine (ie, the amount of air to be reduced). That is, according to the switching state of the air conditioner, the power steering, and the electric load (hot wire defogger, headlight, electric fan, etc.) to the non-operation state, a preset required intake air flow rate for each load is searched, and these are summed. Then, the required change amount Q ₂ of the intake air flow rate (the amount of air to be reduced) is determined.

In the next step 30, the current actual slot is
The throttle valve opening TVO₁From the throttle sensor 7
Detect based on number. Then, in step 40, the current
Actual actual throttle valve opening TVO₁Based on FIG. 5,
Referring to the table, the current intake air flow rate Q₁Detect
You. In step 50, the current suction determined in step 40 is determined.
Incoming air flow Q₁From the load fluctuations found in step 20
Change in intake air flow required to suppress rotational fluctuations caused by
Q_Two(Air volume to be reduced)
Mark Q_Three(= Q₁−Q _Two).

In step 60, the final control target Q ₃ (=
Based on Q ₁ -Q ₂ ), the target throttle valve opening TVO ₂ is detected with reference to the table of FIG. Then, in step 70, as the target throttle valve opening TVO ₂ is obtained, the actuator 4 sends a driving signal, the throttle valve 3 and opening control, the flow ends.

As described above, according to this embodiment, when the load fluctuates during the idling operation, the current intake air flow rate is obtained from the current actual throttle valve opening, and the current intake air flow rate and The target throttle valve opening is obtained based on the sum of the intake air flow rate (including the increase side and the decrease side) corresponding to the load fluctuation (the target intake air flow rate), and the actual throttle valve opening degree is calculated based on the target throttle valve opening degree. By controlling the degree, the intake air flow rate is changed in accordance with the magnitude of the load fluctuation, so even if there is a non-linear relationship between the throttle valve opening and the intake air flow rate, The throttle valve opening can be controlled with high accuracy according to the intake air flow rate and the intake air flow rate can be controlled. Improve etc. It is possible.

Next, a second embodiment of the present invention will be described. The overall configuration of the second embodiment is the same as that of FIG. 3 described in the first embodiment, and a description thereof will be omitted.
The throttle valve opening control performed by the control unit 50 will be described with reference to the flowchart of FIG. The functions of the intake air flow rate change setting means, the throttle valve opening change amount setting means, the correction means, and the throttle valve opening change control means according to the present invention (the invention according to claim 2) will be described later. The control unit 50 that executes the flowchart of FIG. 8 is provided as software.

In step 100, while the target idle speed is controlled, the auxiliary equipment (air conditioner,
Switching of operation of power steering, alternator, etc. (OFF → O)
N, ON → OFF), and it is determined whether or not a load change (plus side or minus side) occurs. In step 200, the rotation fluctuation is suppressed based on the combined state of the OFF → ON and ON → OFF signals of the input auxiliary equipment (that is, based on the magnitude of the load fluctuation that may occur). The amount of change Q ₂ (the amount of air to be increased or decreased) of the intake air flow required for this purpose is determined. In other words, according to the operating states of the air conditioner, the power steering, and the electric loads (hot wire defogger, headlight, electric fan, etc.), the required required intake air flow rate for each load is set in advance,
Based on these, the required change amount Q ₂ of the intake air flow rate (the amount of air to be increased or decreased) is obtained.

In the next step 300, the throttle valve opening corresponding to the required change amount Q ₂ of the intake air flow rate is referred to by referring to the straight line shown by the broken line in FIG. 9 (the conventional linear characteristic obtained by learning points A and B). obtaining a variation TVO ₃ of TVO. In step 400, the actual current (the pre-change) the throttle valve opening TVO _1, detected on the basis of a signal from a throttle sensor 7.

[0030] Then, in step 500, obtains the correction coefficient K by referring to the broken lines in the table as shown in FIG. 10, based on the current actual throttle valve opening TVO _1, the throttle valve calculated in step 300 the variation TVO ₃ of opening TVO correcting _{(TVO 3 × K = TVO 3} '). As shown in FIG. 10, the correction coefficient K has a characteristic obtained by substantially reversing the variation curve of the actual intake air flow rate variation.

[0031] Then, only the corrected change amount TVO ₃ of the obtained throttle valve opening TVO and 'in step 500, by varying the current throttle valve opening TVO ₁ (decrease or increase), and the flow ends . As described above, according to the present embodiment, the amount of change in the throttle valve opening corresponding to the intake air flow rate to be changed in accordance with the load variation is accurately determined by the fact that the actually changed intake air flow rate is accurately set to the target value (the load variation). (The intake air flow rate to be changed according to the current throttle valve opening), so that there is a non-linear relationship between the throttle valve opening and the intake air flow rate. However, with a relatively simple and inexpensive configuration, the throttle valve opening and the intake air flow rate can be controlled with high accuracy in response to load fluctuations. The rotation speed can be controlled and maintained at the target value, and the engine operability and the like can be improved.

[0032]

As described above, according to the present invention,

[Brief description of the drawings]

FIG. 1 is a block diagram of the invention according to claim 1;

FIG. 2 is a block diagram of the invention according to claim 2;

FIG. 3 is a system configuration diagram according to the first embodiment;

FIG. 4 is a flowchart illustrating throttle valve control according to the first embodiment;

[5] from the current actual (before the change) of the throttle valve opening TVO _1, for detecting the current intake air flow rate Q ₁ table

[6] from the control target _{Q 3 (= Q 1 + Q} 2), for detecting a target throttle valve opening TVO ₂ table

FIG. 7 is a flowchart for explaining throttle valve control according to the first embodiment (an example on the negative side of load fluctuation);

FIG. 8 is a flowchart illustrating throttle valve control according to a second embodiment.

FIG. 9 is a diagram showing a non-linear relationship between a throttle valve opening TVO and an intake air flow rate Q, and a linear characteristic obtained by learning points A and B;

FIG. 10 shows a variation characteristic of the variation ΔQ of the intake air flow rate with respect to the throttle valve opening at the start of the step control (before the change) when the throttle valve opening is changed by a certain amount;
The figure which shows the correction coefficient K.

[Explanation of symbols]

 Reference Signs List 1 engine 3 throttle valve (intake throttle valve) 4 actuator (electric motor etc.) 7 throttle sensor 8 crank angle sensor 9 water temperature sensor 10 idle switch 11 air conditioner switch 12 power steering switch 13 electric load switch 50 control unit

 ──────────────────────────────────────────────────の Continuing on the front page (72) Munehiro Kudo 1370 Onna, Atsugi-shi, Kanagawa Prefecture Inside Yunicia Gex Co., Ltd.

Claims (3)

[Claims] An electronically controlled throttle valve control device capable of adjusting an opening independently of a driver's accelerator operation, comprising: a throttle valve opening detecting means for detecting a current throttle valve opening; An intake air flow rate detecting means for detecting a current intake air flow rate based on a current throttle valve opening degree in consideration of a non-linear relationship between a valve opening degree and an intake air flow rate; and an intake air demand corresponding to a load change. Intake air flow rate change amount setting means for setting a flow rate change amount; a current intake air flow rate detected by the intake air flow rate detection means; and an intake air flow rate change amount set by the intake air flow rate change amount setting means. And a target intake air flow rate setting means for setting a target intake air flow rate based on the target intake air flow rate. Target throttle valve opening setting means for setting a target throttle valve opening based on the target intake air flow rate set by the stage; and a target set by the target throttle valve opening setting means when there is a load change. An electronically controlled throttle valve control device, comprising: throttle valve control means for controlling a throttle valve to a throttle valve opening via an actuator. 2. An electronically controlled throttle valve control device capable of adjusting an opening independently of an accelerator operation by a driver, wherein the control device sets a required amount of change in an intake air flow rate in response to a load change. Intake air flow rate change amount setting means, and a throttle valve opening degree based on the intake air flow rate change amount set by the intake air flow rate change amount setting means according to a linear relationship between a predetermined throttle valve opening and the intake air flow rate. Throttle valve opening change amount setting means for setting the change amount; throttle valve opening detecting means for detecting the current throttle valve opening degree; current throttle valve opening degree; non-linearity of throttle valve opening degree and intake air flow rate Correction means for correcting the throttle valve opening change amount set by the throttle valve opening change amount setting means with a correction coefficient set based on And a throttle valve opening change control unit that changes the current throttle valve opening via an actuator by an amount of change in the throttle valve opening corrected by the correction unit. Control device for electronically controlled throttle valve. 3. The method according to claim 2, wherein the correction coefficient is set based on a variation characteristic of a change amount of the intake air flow rate with respect to the throttle valve opening before the change when the throttle valve opening is changed by a predetermined amount. Item 3. An electronically controlled throttle valve control device according to item 2.