JPH0826787B2 - Output control device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an internal combustion engine
Said) for controlling the output.

[Conventional technology]

In recent years, the throttle bore diameter has been increased from the viewpoint of increasing the output of the engine and improving the acceleration response.

[Problems to be Solved by the Invention]

However, if the throttle bore diameter is increased in this way, as shown in FIG. 9, the lower the engine speed Ne, the sooner the throttle valve opening leaves the fully closed position, the more the air amount that is almost fully opened passes immediately. Therefore, when the engine speed Ne is low, it is particularly difficult to control the output of the engine, and there is a problem in that engine stall (engine stop) during clutch meet and vehicle jerkyness during running are likely to occur.

The present invention is intended to solve such a problem, and provides an output control device for an internal combustion engine, which is adapted to appropriately change the intake air amount due to the change in the opening of the throttle valve. To aim.

[Means for solving the problem]

Therefore, the output control device for an internal combustion engine according to the present invention is provided with a first throttle valve which is provided in an intake passage of the internal combustion engine and mechanically interlocks with an artificial operation member, and an upstream side or a downstream side of the first throttle valve. A second throttle valve provided in the intake passage, an actuator that drives the second throttle valve to open and close, and a second throttle valve that follows the opening and closing of the first throttle valve by the artificial operation member by controlling the actuator. When opening and closing the two throttle valves, the opening degree of the second throttle valve is made smaller than the opening degree of the first throttle valve in the throttle valve middle opening area, and the first throttle opening is made in the throttle valve fully opening area. The ratio of the opening degree of the second throttle valve to the opening degree of the valve is defined as the ratio of the opening degree of the second throttle valve to the opening degree of the first throttle valve in the opening degree region of the throttle valve. As larger than the ratio of the degree is characterized by being configured to include a control means for controlling the actuator.

[Work]

In the above-described output control device for an internal combustion engine of the present invention, the first throttle valve rotates in conjunction with the artificial operation member, but the second throttle valve controls the actuator by the control means, thereby reducing the throttle. The opening degree of the second throttle valve is adjusted to be smaller than the opening degree of the first throttle valve in the valve opening area, and the opening degree of the first throttle valve is adjusted to the opening degree in the throttle valve fully opening area. The ratio of the opening degree of the second throttle valve is adjusted to be larger than the ratio of the opening degree of the second throttle valve to the opening degree of the first throttle valve in the middle opening area of the throttle valve.

〔Example〕

An output control device for an internal combustion engine according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an engine system having the device, and FIG. 2 is an engine control system having the device. 3 is a block diagram showing the same, FIG. 3 (a) is a main block diagram for implementing the first control mode, and FIG. 3 (b) is a main block diagram for implementing the second control mode. FIG. 4 is a flow chart for explaining the first control mode, and FIG. 5 is a diagram showing the relationship between the main throttle opening and the engine speed for use in explaining the first control mode. FIG. 7 is a flow chart for explaining the second control mode, and FIGS. 7A and 7B show the relationship between the main throttle opening and the engine speed, which are used for explaining the second control mode. Shown in Figure 8 is May. The relationship between the throttle opening and the intake manifold pressure is a diagram for explaining how to change during the period from the hard mode to mild mode.

Now, the gasoline engine system with this device is
As shown in FIG. 1, the engine (internal combustion engine) E is configured as a V-type 6-cylinder engine in FIG.

An intake passage (supply system) 2 and an exhaust passage (exhaust system) are provided in the combustion chamber 1 of each cylinder of the engine E (the ignition portion of the spark plug is exposed in the combustion chamber 1 (not shown)). ) 3 are connected for communication, and the intake passage 2 and each combustion chamber 1 are controlled to communicate by an intake valve 4, and
The exhaust passage 3 and each combustion chamber 1 are controlled to communicate with each other by an exhaust valve 5.

In addition, the intake passage 2 has an air cleaner in order from the upstream side.
6, Output control sub-throttle valve (second throttle valve) 7
B, Main throttle valve for output control (first throttle valve)
7A and electromagnetic fuel injection valve (solenoid valve; injector) 8
The exhaust passage 3 is provided with a catalytic converter (three-way catalyst) and a muffler (silencer) for purifying exhaust gas, which are not shown in the order from the upstream side of the exhaust passage 3. Note that a surge tank 2a is provided in the intake passage 2.

Further, the solenoid valves 8 are provided in the intake manifold portion by the number of cylinders. Since the engine E of this embodiment is a V-type 6-cylinder engine, six electromagnetic valves 8 are provided. That is, so-called multi-point combustion injection (MP
It can be said that it is a type I engine.

By the way, the main throttle valve 7A is linked to an accelerator petal (artificial operation member) 100 in the passenger compartment via an accelerator cord 101, whereby the main throttle valve 7A is connected.
Is rotated according to the amount of depression of the accelerator petal 100.

Further, as described above, the sub-throttle valve 7B is arranged in tandem (or in series) with the main throttle valve 7A on the upstream side of the main throttle valve 7A, but the sub-throttle valve 7B is an electric motor as an actuator. It is adapted to be rotationally driven by a (motor) 70. A stepper motor, a DC motor, or the like is used as the motor 70.

And in this case, these two throttle valves 7A, 7B
Are arranged in tandem, the intake air amount is determined by whichever of the throttle valve openings is smaller.

Therefore, an amount of air corresponding to the smaller opening of the throttle valve 7A or 7B is sucked in through the air cleaner 6, and this air has a proper air-fuel ratio with the fuel from the solenoid valve 8 in the intake manifold portion. Mixed in the combustion chamber 1
After the ignition plug is ignited at an appropriate timing to be burned to generate engine torque, the mixture is discharged as exhaust gas into the exhaust passage 3,
The catalytic converter purifies the three harmful components of CO, HC, and NO _x in the exhaust gas, and then the muffler silences them and releases them to the atmosphere.

In addition, main throttle valve 7A, sub throttle valve 7B
Two bypass passages 2A and 2B that bypass these throttle valves 7A and 7B are provided in parallel with the portion where the idle speed control valve (ISC valve) 10 is provided. In addition, the fast idle air valve (FIA
Valve) 16 is provided.

Here, the idle speed control valve 10
A stepping motor (stepper motor) 10a, a valve body 10b that is driven to open and close by the stepper motor 10a, and a return spring 10c that urges the valve body 10b in a closing direction are configured.

The stepper motor 10a has four coil parts arranged in an annular shape, and has a rotor (rotating part) in a space surrounded by these coil parts. Unipolar, two-phase excitation type), when the pulse signals are received in a predetermined order of the coil portion, the coil portion is rotated right and left by a predetermined angle.

Further, the rotor of the stepper motor 10a is coaxially arranged with the rod 10d having the valve body 10b, and is screwed to these from the outside. Further, the rod 10d is provided with a rotation stop. As a result, when the stepper motor 10a is rotated, the rod 10d with the valve element 10d moves along the axial direction, and the valve opening degree changes. As a result, the idle speed can be controlled by changing the amount of intake air flowing through the intake passage 2 without depressing the accelerator pedal during idling.

The fast idle air valve 16 is of a wax type.
2B is opened, and as the engine temperature rises, it extends and closes bypass path 2B.

Further, a bypass passage 2C that bypasses the throttle valve 7B is provided in parallel with the portion where the sub throttle valve 7B is provided, and a bypass valve 71 is provided in this bypass passage 2C. Bypass valve 71 is diaphragm 71
The control passage 73 is connected to one of the two chambers 71b, 71c partitioned by a, and the control passage 73 is applied to the one chamber 71b through the control passage 72 so that the rod 71d is attached to the diaphragm 71a. It drives the valve body 71e connected via the opening and closing the bypass passage 2C,
Opening / closing control by the bypass valve 71 is performed by a solenoid valve 73 interposed in the control passage 72. In the control passage 72, an orifice 74a and a check valve 74b are provided in parallel with each other.

Therefore, even if the sub-throttle valve 7B is twisted into a fully closed state, a signal is sent to the solenoid valve 73 to open the bypass valve 71 so that the intake air flows through the bypass passage 2C to the main throttle valve 7A. Can be supplied to the side. The solenoid valve 73 is controlled to open the bypass valve 71 when the output of the sub-throttle sensor 14B (described later) does not change at all even though the sub-throttle valve control signal changes, for example. To be done.

Further, the engine E is subjected to various controls such as sub-throttle valve control, fuel supply control, ignition timing control, idle speed control, etc., but various sensors are provided for performing such control. .

First, on the intake passage 2 side, an air flow sensor 11 that detects the intake air amount from the Karman vortex information, an intake temperature sensor 12 that detects the intake air temperature, and an atmospheric pressure sensor (not shown) that detects the atmospheric pressure are provided. ing.

In addition, in the portion where the main throttle valve is provided in the intake passage 2, the main throttle valve
A potentiometer-type main throttle sensor 14A for detecting the opening of 7A and an idle switch 15 for detecting an idling state are provided.

Further, a potentiometer-type sub-throttle sensor 14B for detecting the opening degree of the sub-throttle valve 7B and a fully-open switch 24 for detecting the fully open state of the sub-throttle valve 7B are provided at the portion where the sub-throttle valve in the intake passage 2 is provided. There is.

Further, the oxygen concentration (O ₂ concentration) in the exhaust gas is detected at the upstream side portion of the catalytic converter on the exhaust passage 3 side.
An O ₂ sensor 17 (see FIG. 2) is provided.

Here, the O ₂ sensor 17 is an application of the principle of a solid electrolyte oxygen concentration battery, and its output voltage has a characteristic that it changes rapidly near the stoichiometric air-fuel ratio, and the voltage on the lean side of the theoretical air-fuel ratio is Low, the voltage on the rich side is higher than the stoichiometric air-fuel ratio. That is, these O ₂ sensors 17 are configured as so-called λ type O ₂ sensors.

As other sensors, as shown in FIGS. 1 and 2, a water temperature sensor 19 for detecting the engine cooling water temperature is provided, and a crank angle sensor 21 for detecting the crank angle is provided.
(The crank angle sensor 21 also serves as a rotation speed sensor for detecting the engine rotation speed) and a TDC sensor 22 for detecting the top dead center of the first cylinder (reference cylinder) are provided in the distributor.

In the passenger compartment (for example, a portion that can be easily operated from the driver's seat), the operation mode selector switch 25 or the operation mode switching switch 25 for switching the operation mode between the hard (HARD) mode and the mild (MILD) mode. There is provided an operation mode selection volume 25 'for multi-step or stepless selection from the hard mode to the mild mode. The meanings of the hard mode and the mild mode will be described later.

The detection signals from these sensors are input to the electronic control unit (ECU) 23 as shown in FIG. Here, EUC23, as shown in FIG. 1, fuel supply control (including idle control),
Engine control computer 23 for controlling ignition timing, etc.
A, each computer has a sub-throttle valve control computer 23B that controls the sub-throttle valve.
The A and 23B have a CPU as its main part. And
The signals from the above sensors are directly input to the input port of the CPU via an appropriate input interface.

Further, the CPU retains the stored contents while the battery is connected to the ROM via the bus line, the ROM for storing the program data and the fixed value data, the RAM which is updated and sequentially rewritten, and the battery. Data is exchanged with the backed-up battery backup RAM (BURAM).

Further, various control signals are output from the computers 23A and 23B to the corresponding control target parts via appropriate output interfaces. As shown in FIG. 2, the control target part is a solenoid valve for fuel injection.
8, stepper motor 10 for idle speed control
a, a power transistor 30 for controlling the ignition timing, a motor 70 for controlling the sub-throttle valve opening, a bypass valve controlling solenoid valve 73, and the like.

Next, a case of controlling the opening of the sub throttle valve 7B will be described.

In this case, the throttle valve opening control signal (sub throttle valve control signal) calculated by the ECU 23 is supplied to the motor 70 to control the opening of the sub throttle valve 7B. .

By the way, in the present embodiment, when the operation mode is set in advance, the throttle valve opening is controlled according to the set motor, but the control mode includes the hard mode and the mild mode. There is a first control mode in which the control is switched between two stages and a second control mode in which the control is switched between a non-step or a multi-step between the hard mode and the mild mode.

First, the first control mode in which the control is switched between the hard mode and the mild mode in two steps will be described.

A control block diagram for the first control mode is as shown in FIG. That is, in this case, the sub-throttle opening degree calculation means 110 is provided.

Here, the sub-throttle opening calculation means 110 receives signals from the operation mode changeover switch 25, the main throttle sensor 14A, the sub-throttle sensor 14B, and the engine speed sensor 21 to open the sub-throttle valve 7B (sub-throttle valve 7B). A signal (sub-throttle valve control signal) that has the calculated sub-throttle opening information.
Are supplied to the motor 70.

Further, the sub-throttle opening degree calculation means 110 will be described in detail. In the sub-throttle opening degree calculation means 110, when the mild mode is selected by the operation mode changeover switch 25, the accelerator pedal 100 is suddenly depressed (a sudden stroke). Acceleration operation) and the sub-throttle opening
When making 90 ° (fully open) and not performing rapid acceleration operation, the target sub-throttle opening θ _SB determined by the opening of the main throttle valve 7A (main throttle opening) and the engine speed is set. A map MP shown in FIG. 5 is used for calculating the target sub-throttle opening θ _SB .

In this map MP, when the main throttle opening is fully closed (5 °), the sub throttle opening (7
) Indicates the fully closed angle of the sub-throttle valve 7B, and the fully closed position of both the main throttle valve 7A and the sub-throttle valve 7B is restricted by a mechanical stopper.

Here, as can be seen from this map MP, at least the throttle valve mid-opening region (in this throttle valve mid-opening region, the main throttle valve 7A becomes the fully open position immediately after the main throttle valve 7A leaves the fully closed position). In the region just before), the sub throttle opening θ _SB is set to be smaller than the main throttle opening. And this degree becomes large, so that an engine speed is small.

In addition, the throttle valve fully open area (main throttle valve
7A fully open position), the ratio of the opening of the sub-throttle valve 7B to the opening of the main throttle valve 7A is calculated from the ratio of the opening of the sub-throttle valve 7B to the opening of the main throttle valve 7A in the middle opening area of the throttle valve. The opening degree of the sub-throttle valve 7B is set so as to increase.

Specifically, as shown in this map MP, for example, when the engine speed is 1 × 10 ³ rpm, the main throttle valve 7A at the throttle valve middle opening region, for example, when the main throttle opening is 45 ° The ratio of the opening of the sub-throttle valve 7B to the opening of the main throttle valve 7A is 20 ° / 45 °, while the ratio of the opening of the main throttle valve 7A to the opening of the main throttle valve 7A in the fully open region of the throttle valve (when the sub-throttle opening is 90 °). The opening ratio of the throttle valve 7B is 90 ° / 90 °,
This is set larger than in the case of the throttle valve middle opening area. The same applies to other engine speed states.

Therefore, the sub-throttle opening degree calculation means 110 follows the opening and closing of the main throttle valve 7A by the accelerator pedal 100, and the opening degree of the sub-throttle valve 7A in the middle opening area of the throttle valve is the opening degree of the main throttle valve 7A. In addition, the sub-throttle valve for the opening of the main throttle valve 7A
The ratio of the opening of 7B is set to the sub-throttle valve 7B with respect to the opening of the main throttle valve 7A in the opening area of the throttle valve.
A control means for controlling the motor 70 is configured so as to be larger than the ratio of the opening degree of.

Next, regarding the operation of the first control mode,
The description will be made mainly using the flowchart of FIG.

In this case, first, in step A1, various input information such as operation mode, main throttle opening, sub-throttle opening, intake air amount, engine speed, etc. is read, and step A2
At, the driving mode determines whether the mild is hard.

Here, when the operation mode is mild, the output of the engine E is controlled so that the sub-throttle opening is set smaller than the main throttle opening corresponding to the depression amount of the accelerator pedal 100 in the throttle valve middle opening region. Mode. Therefore, when this mild mode is selected, it is possible to adjust to the optimum intake air amount without finely adjusting the depression amount of the accelerator pedal 100, and it is possible to prevent engine stall or sudden blowing up, and eventually It is less likely to cause the vehicle to feel jerky during driving.

On the other hand, the operation mode being hard is a mode in which the intake air amount is changed in accordance with the throttle opening degree by following only the depression change amount of the accelerator pedal 100. Therefore, if you select this hard mode, the accelerator pedal 10
Acceleration that follows a 0 step can be realized. That is, a sporty acceleration or start (excellent acceleration response) can be expected.

By the way, if it is determined in step A2 that the operation mode is mild, it is determined in step A3 whether the depression operation of the accelerator pedal 100 is a rapid acceleration operation.
If not, take NO route and step A4
Then, the target sub-throttle opening θ _SB is calculated. The target sub-throttle opening θ _SB is calculated by the sub-throttle opening calculating means 110, and the map MP shown in FIG. 5 is used for the calculation of the sub-throttle opening θ _SB .

Then, thereafter, in step A5, the motor 70 is driven to open / close the sub-throttle valve 7B so that the target sub-throttle opening θ _SB obtained in step A4 is achieved.

If the accelerator pedal 100 is depressed suddenly, the YES route is taken in step A3 and step A
After setting the sub throttle opening θ _SB to 90 ° (corresponding to full open) in 6, the motor 70 is driven in step A5 to drive the sub throttle valve 7B to the fully open position.

As a result, when the mild motor is selected and the accelerator pedal 100 does not suddenly depress, the accelerator pedal 1
Since the sub-throttle valve operation can be performed by the motor 70 independently of the main throttle valve operation by 00 and without affecting the depression amount of the accelerator pedal 100, in the throttle valve middle opening area, the accelerator pedal 100 It is possible to adjust to the optimum intake air amount without finely adjusting the stepping amount of the vehicle, and as a result, it is possible to prevent engine stall and sudden blowing up, and it is hard to cause a jerky feeling when driving. It is a thing. In addition,
Such an effect is particularly remarkable in the low engine speed region.

Further, the ratio of the opening degree of the sub-throttle valve 7B to the opening degree of the main throttle valve 7A is the ratio of the opening degree of the sub-throttle valve 7B to the opening degree of the main throttle valve 7A in the middle opening area of the throttle valve in the throttle valve fully open range. Since the opening of the sub-throttle valve 7B is set so as to be larger than that, the intake air characteristic should be close to a linear one according to the depression amount of the accelerator pedal 100, as shown in FIG. Can be done.

When the hard mode is selected with the operation mode selector switch 25, the HARD route is taken in step A2, and the sub throttle opening θ _SB is set to 90 ° (corresponding to full opening) in step A6, and then step A5 Then, the motor 70 is driven to drive the sub throttle valve 7B to the fully open position.

Thus, when the operation mode is hard, the intake air amount is controlled only by the main throttle valve 7A, so that the intake air amount changes in accordance with the depression change amount of the accelerator pedal 100. Therefore, if this hard mode is selected, it is possible to expect sporty acceleration or start-up following the depression of the accelerator pedal 100.

In this way, the opening / closing control of the main throttle valve 7A can be performed by the accelerator pedal 100 via the mechanical drive system using the accelerator line as usual, and the opening / closing control of the sub throttle valve 7B is also performed by using the motor 7. Therefore, the hardware portion of the present device can be constructed only by arranging the motor-driven sub-throttle valve 7B in tandem with respect to the mechanical system-driven main throttle valve 7A.

Further, the opening of the motor-driven sub-throttle valve 7B is set to be smaller than the main throttle opening at least in the opening area of the throttle valve, provided that the mild motor is selected. So
Even if the main throttle valve 7A leaves the fully closed position, the sub-throttle valve 7B can control the air volume so that a large amount of air does not flow. In the valve opening range, it is possible to adjust the optimum intake air amount without finely adjusting the depression amount of the accelerator pedal 100, and as a result, it is possible to prevent engine stall or sudden blowing up, As a result, it is difficult for the vehicle to feel jerky during driving. It should be noted that this effect is particularly remarkable in the low engine speed region.

Further, in the throttle valve middle opening area, the opening of the main throttle valve 7A is made smaller than the opening of the sub throttle valve 7B, and in the throttle valve fully open area, the sub throttle valve 7B with respect to the opening of the main throttle valve 7A. By setting the opening of the sub-throttle valve 7B such that the ratio of the opening of the sub-throttle valve 7B is larger than the ratio of the opening of the sub-throttle valve 7B to the opening of the main throttle valve 7A in the throttle valve middle opening area. In addition to suppressing the change in intake air amount when opening and closing the main throttle valve 7A with the accelerator pedal 100 near the fully closed throttle valve,
The suppression can be canceled near full opening, and as shown in FIG.
The intake air characteristic can be approximated to a linear one according to the depression amount of the accelerator pedal 100.

On the other hand, when the hard mode is selected, in the throttle valve mid-opening area, control is not performed such that the sub-throttle opening becomes smaller than the main throttle opening, and engine output control is performed only by the main throttle valve 7A. Since it is performed in, it becomes possible to drive with an emphasis on acceleration response.

Next, a second control mode for switching control between the hard mode and the mild mode steplessly or in multiple steps will be described.

A control block diagram for the second control mode is shown in FIG. 3 (b). That is, in this case, the sub-throttle opening calculation means 111 as the control means.
have.

Here, the sub-throttle opening degree calculation means 111 includes an operation mode selection volume 25 ', a main throttle sensor 14A,
The signal from the sub-throttle sensor 14B and the engine speed sensor 1 is received to calculate the sub-throttle opening. The signal having the calculated sub-throttle opening information (sub-throttle valve control signal) is sent to the motor 70. It is being supplied.

Further, the sub-throttle opening calculation means 111 will be described in detail. In the sub-throttle opening calculation means 111, the main throttle opening and the engine are _opened in accordance with the operation mode ratio V _MODE selected by the operation mode selection volume 25 ′. The target sub-throttle opening degree θ _SB determined by the number of revolutions is set, and the following equation is used when calculating the target sub-throttle opening degree θ _SB .

θ _SB = K · θ _SBMILD + (1-K) · θ _SBHARD · (1) where K = V _MODE / 5 (5 is the number of volts corresponding to the full range of the volume), and θ _SBMIND is The sub-throttle opening in mild _mode.The sub-throttle opening θ _{SBMILD in} this mild mode is a map MPI determined by the main throttle opening and the engine speed.
[See FIG. 7 (a)], θ _SBHARD is the sub-throttle opening in the hard mode, and the sub-throttle opening θ _{SBHARD in} this hard mode is the main throttle opening and the engine speed. Map MP2 determined by the number
This is stored in [See FIG. 7 (b)]. Here, in the map MP1, the main throttle opening is fully closed (5 °)
The sub-throttle opening (7 °) is the full closing angle of the sub-throttle valve 7B.

The sub-throttle opening degree calculation means 111 sets the sub-throttle opening degree to 90 ° (fully open) when the accelerator pedal 100 is suddenly depressed (a sudden acceleration operation is performed).

Here, as can be seen from these maps MP1 and MP2, the sub-throttle opening degrees θ _SBMILD and θ _SBHAD are set to be smaller than the main throttle opening degree at least in the throttle valve _mid- opening area. And this degree becomes large, so that an engine speed is small. Therefore, the target sub-throttle opening θ obtained by linearly interpolating these sub-throttle _openings θ _SBMILD , θ _{SBHARD according} to the mild and hard degree V _MODE using the equation (1)
_{SB is} also set to be smaller than the main throttle opening degree at least in the throttle valve opening degree region.

Therefore, this sub-throttle opening degree calculation means 111 also constitutes a control means for controlling the motor 70 so that the opening degree of the sub-throttle valve 7B is smaller than the opening degree of the main throttle valve 7A at least in the throttle valve middle opening area. To do.

Next, regarding the operation of the second control mode,
The description will be given mainly using the flowchart of FIG.

In this case, first, in step B1, various input information such as the main throttle opening, sub-throttle opening, intake air amount, engine speed, etc. is read, and in step B2, the operation set by the operation mode selection volume 25 'is read. Read the mode percentage V _MODE .

Then, in step B3, it is determined whether or not the depression operation of the accelerator pedal 100 is a rapid acceleration operation. If not, the NO route is taken and the target sub-throttle opening θ _SB is calculated in step B4. The sub-throttle opening degree θ _SB is calculated by the sub-throttle opening degree calculation means 110. When calculating the sub-throttle opening degree θ _SB , as described above, referring to FIGS. 7 (a) and 7 (b). The values obtained from the shown maps MP1 and MP2 are substituted into the equation (1).

Then, thereafter, in step B5, the motor 70 is driven to open / close the sub-throttle valve 7B so that the target sub-throttle opening θ _SB obtained in step B4 is achieved.

In this case, as can be seen from FIGS. 7 (a) and 7 (b), comparing the sub-throttle opening degrees for the mild mode and the hard mode, the set sub-throttle opening degree is set in the middle throttle opening area. Since the value of is smaller for the mild mode than for the hard mode, the relationship between the main throttle opening and the intake manifold pressure is as shown in FIG. Various characteristics can be adopted between the characteristics and the characteristics in the mild mode in which the rising is gentle. This means that the closer to the hard mode, the larger the amount of air that can be put in by opening the throttle opening a little from the fully closed position. Therefore, the closer to the hard mode, the more acceleration-oriented driving can be performed. . On the other hand, the closer to mild mode, the throttle opening is slightly opened from the fully closed position, which means that a large amount of air does not suddenly enter.Therefore, the closer to mild mode, the more depressing the accelerator pedal 100 is. It is possible to adjust the intake air amount to an optimum value even without adjusting to, and as a result, it is possible to prevent engine stall and sudden blow-up, and it is difficult to cause the vehicle to feel jerky during running.

Further, in the sub-throttle opening for the mild mode shown in FIG. 7A, the ratio of the opening of the sub-throttle valve 7B with respect to the opening of the main throttle valve 7A in the throttle valve fully open region is set as The opening of the sub-throttle valve 7B is set so as to be larger than the ratio of the opening of the sub-throttle valve 7B to the opening of the main throttle valve 7A.

Specifically, as shown in FIG. 7A, for example, when the engine speed is 1 × 10 ³ rpm, the main opening at the throttle valve middle opening area, for example, when the main throttle opening is 45 ° While the ratio of the opening of the sub-throttle valve 7B to the opening of the throttle valve 7A is 15 ° / 45 °, the fully open region of the throttle valve (main throttle opening is
The ratio of the opening of the sub-throttle valve 7B to the opening of the main throttle valve 7A (at 90 °) is 70 ° / 90 °, which is larger than that in the middle opening range of the throttle valve. The same applies to other engine speed states.

Therefore, as the mode is closer to the mild mode, as shown in FIG. 8, the intake air characteristic can be made closer to a linear one according to the depression amount of the accelerator pedal 100 even in the vicinity of the throttle valve fully open region.

If the accelerator pedal 100 is a sudden acceleration operation, the YES route is taken in step B3 and the step B
In step 6, after setting the sub throttle opening θ _SB to 90 ° (corresponding to full open), in step B5, the motor 70 is driven to drive the sub throttle valve 7B to the fully open position.

As a result, by using this second control mode, in addition to the effect or advantage obtained in the first control mode described above, it is possible to select from a mild mode to a hard mode in multiple stages or in a non-stage manner. Therefore, the range of operation modes can be widened and various driving methods can be realized.

By the way, regarding fuel supply control (air-fuel ratio control),
A control signal for fuel injection is output from the ECU 23 to sequentially drive the six solenoid valves 8. For this purpose, fuel supply means for supplying fuel according to the operating state of the engine E is provided. However, this fuel supply means includes basic drive time determination means, air-fuel ratio correction coefficient setting means, O ₂ sensor feedback correction means, cooling water temperature correction means, intake air temperature correction means, acceleration increase correction means, dead time correction means. Have

Here, the basic driving time determining means, intended to determine the basic drive time T _B for the electromagnetic valve 8, the basic drive time determining means based on the intake air amount information from the air flow sensor 11 (engine load information) The basic driving time T _B is decided.

Further, the air-fuel ratio correction coefficient setting means is for setting the air-fuel ratio correction coefficient K _AF corresponding to the engine speed and the engine load (intake air quantity / engine speed information) from the map, O ₂ sensor feedback correction means Is for setting the air-fuel ratio correction coefficient K _FB used during O ₂ sensor feedback, and these air-fuel ratio correction coefficient setting means and O ₂ sensor feedback correction means are switched by interlocking switching means. It is supposed to be selected.

The air-fuel ratio correction coefficient K _FB set by the O ₂ sensor feedback correction means is represented by a proportional gain P and an integral gain I, and the integral gain I is ΔI at every crank pulse interruption (or at every constant time). It is updated by adding or subtracting.

Further, the cooling water temperature correction means sets the correction coefficient K _WT according to the engine cooling water temperature, the intake air temperature correction means sets the correction coefficient K _AT according to the intake air temperature, and the acceleration increase correction means increases the acceleration increase amount. The correction coefficient K _AC is set by the dead time correction means, and the dead time correction means sets the dead time (dead time) T _D for correcting the drive time according to the battery voltage.

Accordingly, at the time of O ₂ feedback correction, the drive time T _INJ of the solenoid valve 8 at the _{T B × K WT × K AT} × K FB + K AC + T D, while driving the electromagnetic valve 8 in the time T _INJ, Except for O ₂ feedback correction, drive time T _INJ of solenoid valve 8 is changed to T _B
The solenoid valve 8 is driven at this time T _INJ with × K _WT × K _AT × K _AF + K _AC + T _D.

Regarding the ignition timing control, the ECU 23 outputs an ignition timing control signal to turn on / off the power transistor 30 as a switching transistor. The power transistor 30 as a switching transistor is connected to an ignition coil (not shown), and the ignition coil is connected to an ignition plug for each cylinder through a distributor, so that the switching transistor (power transistor) is connected. When 30 is off, the spark plug distributed by the distributor is set to ignite.

Further, for idle speed control, the ECU 23 outputs an ISC control signal to rotate the stepper motor 10a.

Note that the operating mode is not set, and the sub-throttle valve
The opening of 7B may be controlled to be smaller than that of the main throttle valve 7A.

In this case, step A2 may be omitted in FIG.

Further, as the actuator used for the above sub-throttle valve control, a pressure responsive mechanism, a fluid pressure motor, a linear solenoid or the like can be used in addition to the electric motor.

Further, as the artificial operation member, in addition to the accelerator pedal 100 operated by the occupant with the foot, a member manually operated by the occupant may be used.

〔The invention's effect〕

As described above in detail, according to the output control device of the internal combustion engine of the present invention, the first throttle valve mechanically interlocked with the artificial operation member provided in the intake passage of the internal combustion engine, and the first throttle valve
A second throttle valve provided in the intake passage upstream or downstream of the throttle valve, an actuator that opens and closes the second throttle valve, and the first operation by the artificial operation member by controlling the actuator. When opening and closing the second throttle valve following the opening and closing of the throttle valve, the opening degree of the second throttle valve is made smaller than the opening degree of the first throttle valve in the throttle valve middle opening area, and In the throttle valve fully open region, the ratio of the opening amount of the second throttle valve to the opening amount of the first throttle valve is defined as the opening amount of the second throttle valve with respect to the opening amount of the first throttle in the middle opening region of the throttle valve. The control means for controlling the actuator is configured so as to be larger than the ratio of the first throttle valve. In the changes in the intake air amount when the opening and closing fully opened near suppresses the full closed neighborhood by releasing the inhibition, can be made closer to the linear ones.

Further, by performing such control, particularly in an engine with a large throttle bore, the intake air amount becomes almost fully open as soon as the throttle valve opening leaves the fully closed position, and the engine output can be adjusted. It is possible to solve the problem that the conventional technique has, which is difficult.

That is, the opening / closing control of the first throttle valve can be performed by an artificial operation member via a mechanical drive system using an accelerator line as in the conventional case, and the opening / closing control of the second throttle valve can also be performed by using an actuator. Therefore, there is an advantage that the hardware part of this device can be constructed only by arranging the actuator-driven second throttle valve in tandem with respect to the mechanical system-driven first throttle valve. The opening is set to be smaller than the first throttle opening, so that even if the first throttle valve leaves the fully closed position, the second throttle valve prevents the large amount of air from flowing. Therefore, in the throttle valve middle opening area, even if the stepping amount of the artificial operation member is not finely adjusted,
There is an advantage that the intake air amount can be adjusted to an optimum amount, and as a result, engine stall and sudden blow-up can be prevented.

[Brief description of drawings]

1 to 8 show an output control device of an internal combustion engine as an embodiment of the present invention. FIG. 1 is an overall configuration diagram showing an engine system having the present device, and FIG. 2 has the present device. FIG. 3 (a) is a block diagram showing an engine control system, FIG. 3 (a) is a block diagram of a main part for implementing the first control mode, and FIG. 3 (b) is a block diagram for implementing the second control mode. 4 is a flow chart for explaining the first control mode, and FIG. 5 shows the relationship between the main throttle opening and the engine speed for use in explaining the first control mode. FIGS. 6 and 6 are flowcharts for explaining the second control mode, and FIGS. 7A and 7B are main throttle opening and engine speed for use in explaining the second control mode, respectively. Fig. 8 showing the relationship with
The figure illustrates how the relationship between the main throttle opening and the intake manifold pressure changes from the hard mode to the mild mode. FIG. 9 shows the throttle opening and intake manifold in an engine with a large throttle bore. It is a figure explaining the relationship with pressure. 1 ... Combustion chamber, 2 ... Intake passage, 2A-2C ... Bypass passage, 2a ... Surge tank, 3 ... Exhaust passage, 4 ... Intake valve, 5 ... Exhaust valve, 6 ... Air cleaner, 7A ...... Main throttle valve (first throttle valve), 7B ... Sub throttle valve (second throttle valve), 8 ... Electromagnetic valve, 10 ... IS
C valve, 10a ... Stepper motor, 10b ... Valve body, 10c ...
Return spring, 10d Rod, 11 Air flow sensor, 12 Intake air temperature sensor, 14A Main throttle sensor, 14B Sub throttle sensor, 15
Idle switch, 16 ... Fast idle valve, 17
…… O ₂ sensor, 19 …… Water temperature sensor, 21 …… Crank angle sensor (engine speed sensor), 22 …… TDC sensor, 23
...... Electronic control unit (ECU), 23A ...... Engine control computer, 23B ...... Sub throttle valve control computer, 25 ...... Operation mode selector switch, 25 '...... Operation mode selection volume, 30 ...... Ignition timing control Power transistor, 70 …… Motor (actuator), 71 ……
Bypass valve, 71a ... diaphragm, 71b, 71c ... chamber, 71d ... rod, 71e ... valve body, 72 ... control passage, 73 ... solenoid valve, 74a ... orifice, 74b ...
Check valve, 100 ... Accelerator pedal (artificial operation member), 101 ... Accelerator line, 110, 111 ... Target sub-throttle opening calculation means as control means, E ... Engine.

Claims (1)

[Claims] 1. A first throttle valve provided in an intake passage of an internal combustion engine and mechanically interlocked with an artificial operation member, and a second throttle valve provided in the intake passage upstream or downstream of the first throttle valve. A throttle valve; an actuator for driving the second throttle valve to open and close; and a second actuator for controlling the actuator to open and close the second throttle valve following the opening and closing of the first throttle valve by the artificial operation member. In the middle opening area of the throttle valve, the opening degree of the second throttle valve is made smaller than the opening degree of the first throttle valve, and in the fully open area of the throttle valve, the second opening degree with respect to the opening degree of the first throttle valve. The ratio of the opening degree of the throttle valve is made larger than the ratio of the opening degree of the second throttle valve to the opening degree of the first throttle valve in the throttle valve middle opening area. In, characterized in that it is configured to include a controller for controlling the actuator, the output control device for an internal combustion engine.