JP2833035B2 - Output control device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an internal combustion engine provided with a second traction control throttle valve in addition to a normal first throttle valve linked to an accelerator pedal in an engine intake passage. It relates to an output control device.

<Prior Art> A second throttle valve is connected in series with a first throttle valve interlocked with an accelerator pedal in order to prevent the wheels from slipping when the vehicle accelerates on an icy road or a snowy road and the vehicle is swung laterally. When the slip state is detected by detecting the slip state of the wheels, that is, when the slip state is detected by calculating the difference between the rotation speed of the driven wheel and the rotation speed of the driven wheel detected by the wheel rotation speed sensor, the traction control request signal is output. There has been proposed a device provided with a device (hereinafter, referred to as a traction control device) that is issued to control the second throttle valve to a closed side and thereby reduce the torque of the engine to reduce the driving force (hereinafter referred to as a traction control device). See JP-A-61-60331).

Here, the second throttle valve for traction control is
When the traction control request does not occur, it is always at the fully open position, and only when the traction control request occurs, is controlled to the closed position according to the request (slip ratio).

<Problems to be Solved by the Invention> Here, in the tandem throttle chamber used in the conventional output control device, the second throttle valve for traction control is rotated by a step motor attached to one end of a valve shaft. The opening TVO of the second throttle valve is detected by a potentiometer type throttle sensor attached to the other end.

Here, the present applicant stops the feedback control of the air-fuel ratio during the traction control operation so that the air-fuel ratio when the internal combustion engine is in a transient state is made appropriate, thereby preventing the deterioration of the combustion state during the traction control. (See Japanese Patent Application No. 63-25957), but the control is becoming complicated and detailed.

Therefore, when the second throttle valve, which is fully open when there is no traction control request, shifts to the closed side when a traction control request is generated, the actual movement amount for the request is measured by the throttle sensor. Therefore, it is necessary to input the absolute opening degree of the second throttle valve from the fully closed position to the control unit in order to perform accurate control. However, there is an assembly error between the second throttle valve and the tandem throttle chamber, Further, since there is a mounting error of the throttle sensor and the like, if the opening degree of the second throttle valve is calculated backward from the fully opened position, the detection accuracy may be reduced due to the various errors.

Therefore, when the second throttle valve is fully closed, it is conceivable to calibrate the throttle sensor by using the output of the throttle sensor at the fully closed position. However, since the intake air flow rate becomes zero, the driver needs to perform calibration. Even if the accelerator pedal is operated, the amount of intake air does not increase, and if the calibration is not performed in consideration of the timing, the driving performance may be uncomfortable.

Accordingly, an object of the present invention is to provide an output control device for an internal combustion engine that learns a fully closed position of a second throttle valve so that output control of the internal combustion engine is accurately performed without causing a feeling of incompatibility in driving performance. I do.

<Means for Solving the Problems> For this reason, as shown in FIG. 1, the present invention is provided under a predetermined operating condition of the vehicle separately from a normal first throttle valve which is interlocked with an accelerator pedal in an engine intake passage. The second control is performed in the fully closed direction in response to the output traction control request signal.
An output control device for an internal combustion engine having a throttle valve, comprising: an idle operating state detecting means for detecting an idle operating state of the internal combustion engine; and a neutral detecting means for detecting a neutral position of the transmission, and output from both of the detecting means. When the internal combustion engine is idling and the transmission is in the neutral position, the throttle sensor output at the second throttle valve fully closed position is read based on the signal to learn the fully closed position of the second throttle valve. The configuration is such that a position learning means is provided.

<Operation> With this configuration, when it is detected that the engine is in the idling state and the transmission is in the neutral position, the fully closed position of the second throttle valve is determined by the throttle sensor output of the second throttle valve fully closed position. At this time, the driver does not perform the accelerator operation and the output of the internal combustion engine is not involved in the running of the vehicle. Thus, the fully closed position of the second throttle valve is learned without affecting the running of the vehicle and without affecting the so-called idling operation of the driver.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings.

First, the system configuration of the output control device for an internal combustion engine will be described with reference to FIG.

In the engine 1, intake air is supplied to each cylinder through an intake passage 2 and a throttle chamber 3, and fuel is injected and supplied by a fuel injection valve 4. Then, the air-fuel mixture in the cylinder is ignited and exploded by the discharge action of a spark plug (not shown), and is discharged to the outside through an exhaust pipe.

Here, the flow of the intake air is controlled by the first throttle valve 11 in the throttle chamber 3 which is opened and closed in conjunction with the depression operation of the accelerator pedal 10. A second throttle valve 12 is disposed in the intake passage 2 upstream of the first throttle valve 11, and the opening of the second throttle valve 12 is controlled by a step motor 14 connected via a rod 13.
The second throttle valve 12 is normally in a fully open state, and when a current is supplied to the step motor 14 by a control signal from a traction control unit 43 described later, the step motor 14 rotates by a predetermined angle, and interlocks with the rotation. Second
Close the throttle valve 12.

Intake air flow rate Q is detected by the air flow meter 20, the opening degree TVO ₁ of the first throttle valve 11 is detected by the throttle opening sensor 21, further, the fully closed position of the first throttle valve 11 is detected by the idle switch 25 These detection signals are output to control units 41 and 43 described later.

Further, the opening degree TVO ₂ of the second throttle valve 12 is detected by the throttle opening sensor 22, the opening degree TVO ₂ signal is once output to the control unit 41 to be described later via the input to the motor control unit 15 buffers 15a Have been.

The control unit 41 further includes a crank angle signal (corresponding to the engine speed) from the crank angle sensor 23, a vehicle speed signal from the vehicle speed sensor 24, and a water temperature sensor 27.
And the water temperature signal from the The detection signal from the neutral switch 26 for detecting the neutral position of the transmission is also transmitted to the control unit 41.
Has been entered.

Also provided are wheel speed sensors 31 to 34 for detecting the rotational speeds of the front, rear, left and right wheels of the vehicle. These detection signals are input to the traction control unit 43, and the traction control unit 43 To detect the slip state. Further, an on / off detection signal from a brake switch 36 for detecting the depressed state of the brake pedal 35 is also input to the traction control unit 43, and the traction control is turned on / off manually by the traction switch 37 by the driver. select.

The control unit 41 receives the above-mentioned various sensor information and a traction control signal from a traction control unit 43 described later, and performs combustion control (air-fuel ratio control and ignition timing control) of the engine.

On the other hand, neutral switch 26, wheel speed sensors 31-3
4.The signals from the brake switch 36 and the traction switch 37 are input to the traction control unit 43. The traction control unit 43 reduces the output torque of the engine based on the sensor information and suppresses the traction of the drive wheels. Control and brake control to prevent slip by lowering the driving force to the wheels. The traction control unit 43 includes a microcomputer and the like,
While signals from 6,31 to 34,35,37, the actual opening signal of the throttle valve 12 from the motor control unit 15, the engine speed from the control unit 41, etc. are input, the traction control unit 43 a control signal for controlling the opening TVO ₂ of the second throttle valve 12 to the motor control unit 15, operation signals for notifying the operating state of the traction control to the control unit 41, a brake control signal to the brake hydraulic actuator 46 Are output respectively.

In the traction control unit 43,
The control of the second throttle valve 12 is performed in accordance with the routine shown in FIG. 3 while communicating with the control unit 41 through the input and output of each signal.

Next, control in the traction control unit 43 will be described with reference to FIGS. 3 and 4. FIG.

In step (denoted by S in the figure, the same applies hereinafter) 1, the learned flag F is determined. If the flag F is 1, the learning has already been performed, and this routine ends.

If the learned flag F is 0, the routine proceeds to step 2, where the idle switch 25 is turned on and off to set the first throttle valve.
It is determined whether or not 11 is the fully closed position.
Proceed to. That is, the idle switch 25 constitutes idle operation state detection means.

In step 3, it is determined whether the neutral switch 26 is on or off. When ON, the gear position of the transmission is in the neutral position, the output of the engine 1 is not transmitted to the drive wheels, and the engine brake and the like are not working. It is determined that the output is not involved, and the process proceeds to step 4. That is,
The neutral switch 26 constitutes a neutral detecting means.

In step 4, since the driver does not operate the accelerator 10 and the output of the internal combustion engine 1 is not involved in the running of the vehicle, even if the second throttle valve 12 is fully closed, the driving performance is uncomfortable. If it does not occur, a current is supplied to the step motor 14 by a control signal from the traction control unit 43 so as to fully close the second throttle valve 12, and the step motor 14 rotates by a predetermined angle.

In step 5, definitive when current second throttle valve 12 to the stepping motor 14 in order to fully closed is supplied in step 4, reads the detection output TVO ₂ of the throttle opening sensor 22.

That detection output TVO ₂ of the throttle opening sensor 22 read in step 5 is the actual opening degree output the throttle opening sensor 22 when the second throttle valve 12 becomes fully closed position is output.

In step 6, the learned flag F is set to F = 1, and the routine ends. The flag F is set to 0 by an initialization routine shown in FIG. 4, which is executed when the engine key switch (or start switch) is turned on.

That is, the traction control unit 43 constitutes a fully closed position learning means.

Thus, since the flag F which is cleared by the initialization routine when the engine key switch is turned on is used, the calibration of the throttle opening sensor 22 is performed every time the engine key switch is turned on so that the output control of the internal combustion engine is accurately performed. Will be performed only once.

Further, the calibration is performed by the idle switch 25 and the neutral switch 26 when the driver does not perform the accelerator operation and the output of the internal combustion engine is not involved in the running of the vehicle, so that the running of the vehicle is affected. And calibration is performed without affecting the so-called idling operation of the driver, and the fully closed position is learned.

Therefore, the second throttle valve is controlled so that the output control of the internal combustion engine is performed accurately without causing a feeling of strangeness in the driving performance.
Twelve fully closed positions are learned.

In the present embodiment, it is constituted idle operating condition detecting means by the idle switch 25, using only the throttle opening degree sensor 21 for detecting an opening TVO ₁ of the first throttle valve 11, by software to output May be used to detect the idling operation state.

<Effects of the Invention> As described above, according to the present invention, when the driver does not perform the accelerator operation and the output of the internal combustion engine is not involved in the running of the vehicle, the second throttle valve is fully opened. Since the output of the throttle sensor at the closed position is read and the fully closed position of the second throttle valve is learned, it does not affect the running of the vehicle and also has an effect on the so-called idling operation of the driver. Thus, learning is performed without giving any uncomfortable feeling in driving performance, and output control of the internal combustion engine can be accurately performed.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims of the present invention, FIG. 2 is a system configuration diagram of an embodiment according to the present invention, and FIGS. 3 and 4 are flowcharts showing a program for output control thereof. 1 ... engine, 11 ... first throttle valve, 12 ... second throttle valve, 21, 22 ... throttle opening sensor, 25 ... idle switch, 26 ... neutral switch, 41 ...
Control unit, 43 ... Traction control unit

Continuation of the front page (56) References JP-A-2-275033 (JP, A) JP-A-62-60936 (JP, A) JP-A-62-23549 (JP, A) JP-A-62-206240 (JP) , A) JP-A-2-233835 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F02D 29/00-29/06 F02D 41/00-41/40 F02D 43/00 -45/00

Claims (1)

(57) [Claims] 1. A second traction control request signal output under a predetermined operating condition of a vehicle is controlled in a fully closed direction separately from a normal first throttle valve linked to an accelerator pedal in an engine intake passage. An output control device for an internal combustion engine having a throttle valve, comprising: an idle operating state detecting means for detecting an idle operating state of the internal combustion engine; and a neutral detecting means for detecting a neutral position of the transmission, and output from both of the detecting means. When the internal combustion engine is idling and the transmission is in the neutral position, the throttle sensor output at the second throttle valve fully closed position is read based on the signal to learn the fully closed position of the second throttle valve. An output control device for an internal combustion engine, comprising a position learning means.