JPH0441944A - Output control device of internal combustion engine - Google Patents

Abstract

PURPOSE:To prevent occurrence of an unsettled air amount at the start of an engine by comparing a former full-open position learning value to a present full-open position learning value, and only when both values are agreed with each other by setting a full-close position learning value to be a present full- close position learning value. CONSTITUTION:A first throttle valve 4 interlocked with an accelerator pedal 3 and a second throttle valve 5 controlled by an actuator 6 at the time of traction controlling are arranged on an intake passage 2 of an engine 1. Throttle sensors 7A, 7B for detecting openings of the throttle valves 4, 5 and a traction control unit 13 for inputting output signals of wheel speed sensors 11a to 11d are provided. When an ignition switch is set ON, an output of the sensor 7B is detected under a full-open condition of the second throttle valve 5 for learning the full-open position, and a full-close position under a full-close condition of the second throttle valve 5 is learned. The former and present full-open position learning values are compared to each other around the learning time. Only when both values are agreed with each other, the former full-close position learning value is set to be a present full-close position learning value.

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to an output control device for an internal combustion engine.

<Conventional technology> Conventionally, in order to prevent the wheels from slipping and swinging laterally when the vehicle accelerates on roads with a low coefficient of friction such as icy roads or snow-covered roads, a system has been installed in the intake passage that is linked to the accelerator pedal. A second throttle valve is provided in series with the first throttle valve, and when a wheel slip condition is detected, the second throttle valve is throttled to reduce the driving force;
Some vehicles are equipped with a device for suppressing slippage, a so-called traction control device (see Japanese Patent Laid-Open No. 1-218932, etc.).

By the way, in such a traction control device, the second
The target opening degree of the throttle valve is calculated by converting the duty signal corresponding to the target opening degree into an angle when fully closed to fully open is 100%.

Therefore, in order to improve the accuracy of engine output control by always accurately driving and controlling the second throttle valve in response to the engine output reduction request signal of traction control, immediately after the ignition switch is turned on from OFF when starting the engine. To, the second
After detecting the throttle sensor output when the throttle valve is fully open and learning the fully open position, the second throttle valve is forced to fully open once, and the throttle sensor output when the second throttle valve is fully closed is detected. It is designed to detect and learn the fully closed position.

<Problems to be Solved by the Invention> However, the conventional second throttle valve fully open/fully closed learning control structure has the following problems.

In other words, if you turn on the ignition switch from OFF and at the same time turn on the starter switch to start the engine,
As mentioned above, in order to learn the fully closed position of the second throttle valve, the second throttle valve
Since the throttle valve is in a fully closed state, the amount of air drops instantaneously, making it impossible to obtain the amount of air necessary for the engine, resulting in poor startability. This is particularly noticeable when the engine temperature is low.

Therefore, in view of the above-mentioned conventional problems, the present invention makes it possible to grasp the fully closed position while omitting drive control for forcing the second throttle valve to the fully closed position under certain conditions. It is an object of the present invention to provide an output control device for an internal combustion engine, which is configured to prevent the air amount from being insufficient when starting the engine as much as possible, thereby improving startability.

<Means for Solving the Problems> For this reason, as shown in FIG. 1, the output control device for an internal combustion engine of the present invention has a normally closed first valve in the intake passage of the engine that is opened and closed in conjunction with the accelerator pedal. An output control device for an internal combustion engine comprising a throttle valve and a normally open second throttle valve that is closed to a predetermined opening degree in response to a valve closing request signal output from a control means, interposed in series. When the ignition switch is turned from OFF to ON, a fully open position learning means detects the output of the second throttle valve position detecting means when the second throttle valve is fully open and learns the fully open position; fully closed position learning means for learning the fully closed position by detecting the output of the second throttle valve position detecting means when the second throttle valve is fully closed by the controlling means; and a comparison means for comparing the fully open position learned value with the fully open position learned value of The configuration includes a setting means for setting as follows.

<Operation> In this configuration, the previous fully open position learned value and the current fully open position learned value are compared, and only when the two values are the same, the previous fully closed position learned value is replaced with the current fully closed position learned value. I am trying to set it as .

That is, the operating range between the fully open position and the fully closed position of the second throttle valve;
In other words, since the span is the same, if the fully open position is the same both last time and this time, the fully closed position is also the same both last time and this time.

Therefore, as a result of setting the previous fully closed position learning value as the current fully closed position learning value, the second throttle valve is forced to fully close for the second throttle valve fully closed learning control. The drive control to the position can be omitted.

As a result, if you turn the ignition switch from OFF to ON and simultaneously turn the starter switch ONL to start the engine, as described above, the second throttle valve will learn the fully closed position.
When the second throttle valve is avoided from being fully closed,
Air that is necessary for the engine can be prevented from decreasing the amount of air! Since it is possible to obtain the same amount, there is no problem with startability.

Therefore, from an overall perspective, compared to the conventional method in which the second throttle valve is forcibly driven to the fully closed position for the second throttle valve fully closed learning control even in the case of It is possible to improve starting performance.

<Example> Embodiments of the present invention will be described below based on the drawings.

In Fig. 2, an internal combustion engine (hereinafter referred to as engine) 1
The intake passage 2 is equipped with a first throttle valve 4 that is linked to an accelerator pedal 3, and a second throttle valve 5 that is throttle-controlled by an actuator such as an electromagnetic motor during traction control, which will be described later, on the downstream side. In the first throttle valve 4,
A first throttle sensor 7A serving as a first throttle valve position detecting means for detecting the opening degree of the throttle valve is connected thereto. Further, a second throttle sensor 7B is connected to the second throttle valve 5 as a second throttle valve position detection means for detecting the opening degree of the second throttle valve 5.

Wheel speed sensors lla to lid are provided to detect the speeds of the front and rear left and right wheels of the vehicle, and each wheel speed sensor l
The traction control unit 13 is equipped with means for calculating a slip rate from variations in each wheel speed based on detection signals from la to lid. When the slip rate is equal to or higher than a predetermined value, the control unit 13 determines that slip has occurred and drives the actuator 6 to perform throttle control (traction control) on the second throttle valve 5 to control the amount of intake air. By automatically reducing engine output and suppressing slippage, the system automatically reduces engine output and stabilizes driving performance.

Here, the traction control unit 13 includes means for controlling the second throttle valve 5 to a fully closed position apart from normal control, and means for controlling the ignition switch 12 from OFF to OFF.
Fully open position learning means that detects the output of the second throttle sensor 7B when the second throttle valve 5 is fully open and learns the fully open position at N time, and a second throttle sensor when the second throttle valve 5 is fully closed. A fully closed position learning means for detecting the output of and learning the fully closed position is provided as software. The traction control unit 13 also includes a comparison means for comparing the previous and current fully open position learned values after learning the fully open position;
A setting means for setting the previous fully closed position learning value as the current fully closed position learning value only when the previous fully open position learning value and the current fully open position learning value are the same based on the comparison result by the comparison means; It is equipped.

Next, the operation of this configuration will be explained based on the flowchart of FIG. 3.

That is, when the ignition switch 12 is turned from OFF to ON, the fully open angle of the second throttle valve 5 at the fully open position is calculated from the output value from the second throttle sensor 7B in step E. In step 2, this fully open angle value is set and stored as the second throttle valve fully open position learning value. In step 3, the previous full-open position learning value and the current full-open position learning value are compared, and if the two values are different, the process proceeds to step 4; if they are the same, the process proceeds to step 5.

In step 4, the second throttle valve 5 is operated to the fully closed position, and in step 6, the fully closed angle of the second throttle valve 5 is calculated from the output value from the second throttle sensor 7B. In step 7, this fully closed angle value is set and stored as the second throttle valve fully closed position learning value.

In step 8, the second throttle valve 5 is returned to the normal control state.

On the other hand, in step 5, the previous fully closed position learned value is set and stored as the current fully closed position learned value.

As is clear from the above explanation, the previous fully open position learned value and the current fully open position learned value are compared, and only when the two values are the same, the previous fully closed position learned value is changed to the current fully closed position. I am trying to set it as a learning value.

In other words, the operating range, or span, between the fully open position and the fully closed position of the second throttle valve 5 is the same, so if the fully open position is the same between the last time and this time, the fully closed position is also the same between the last time and this time. That is why.

Therefore, as a result of setting the previous fully closed position learned value as the current fully closed position learned value, the second throttle valve 5 of the second throttle valve fully closed learning control shown in step 4 is Forced drive control to the fully closed position can be omitted.

As a result, the ignition switch 12 is turned from OFF to OFF.
When the starter switch is turned on at the same time as the N position and the starter switch is turned on to start the engine, the fully closed position of the second throttle valve 5 is learned as described above. This prevents the air volume from decreasing and provides the necessary amount of air for the engine, so there are no problems with starting performance.

Therefore, from an overall perspective, this is better than the conventional method in which the second throttle valve 5 is forcibly driven to the fully closed position for the second throttle valve fully closed learning control in any case. It becomes possible to improve starting performance.

It should be noted that the configuration of the above embodiment does not indicate any structural limitations of the present invention, and the point is that not only the traction control system but also the normally closed first valve, which is opened and closed in conjunction with the accelerator pedal, is installed in the intake passage of the engine. Applicable to other output control devices that are equipped with a throttle valve and a normally open second throttle valve that is closed to a predetermined opening degree in response to a valve closing request signal output from the control means, interposed in series. can do.

<Effects of the Invention> As explained above, according to the output control device for an internal combustion engine of the present invention, the first throttle valve and the second throttle valve are interposed in series in the intake passage of the engine, and the ignition switch OF
When the second throttle valve is turned on from F, the fully open position and fully closed position of the second throttle valve are learned. After learning the fully open position, the previous and current fully open position learned values are compared, and the previous and current fully open position learned values are determined. Since the configuration is such that the previous fully closed position learned value is set as the current fully closed position learned value only at the same time, from an overall perspective, it is possible to set the previous fully closed position learned value as the current fully closed position learned value in any case. This is highly useful as it can improve startability compared to the conventional system in which the drive control forcibly moves the second throttle valve to the fully closed position.

[Brief explanation of drawings]

FIG. 1 is a diagram corresponding to claims of an output control device for an internal combustion engine according to the present invention, FIG. 2 is a system diagram showing one embodiment of the same device, and FIG. 3 is a flowchart explaining the operation of the same embodiment.

Claims (1)

[Claims] A normally closed first throttle valve that opens and closes in conjunction with an accelerator pedal in the intake passage of the engine, and a normally open second throttle valve that closes to a predetermined opening degree in response to a valve closing request signal output from a control means. In an output control device for an internal combustion engine, which is equipped with an ignition switch installed in series,
When the second throttle valve is fully open, there is a fully open position learning means for learning the fully open position by detecting the output of the second throttle valve position detecting means when the second throttle valve is fully open; Fully closed position learning means is provided to learn the fully closed position by detecting the output of the second throttle valve position detection means when the throttle valve is fully closed, and after learning the fully open position, the fully open position learning value of the previous time and this time is determined. and a setting means for setting the previous fully closed position learned value as the current fully closed position learned value only when the previous fully open position learned value and the current fully open position learned value are the same based on the comparison result by the comparing means. An output control device for an internal combustion engine, comprising: