JP2858382B2 - Throttle opening detection device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting the opening of a throttle valve set in an intake passage of an internal combustion engine, and more particularly, to an idle of the internal combustion engine corresponding to the opening of the throttle valve. The present invention relates to a throttle opening detection device for an internal combustion engine, the state of which is determined.

[0002]

2. Description of the Related Art As means for detecting an idling operation state of an internal combustion engine, a normally closed state of a throttle valve is usually detected, and it is determined that the throttle valve is fully closed when idling. As means for detecting such a fully closed state of the throttle valve, for example, there are known devices disclosed in Japanese Patent Publication No. Sho 63-15467 and Japanese Patent Application Laid-Open No. Sho 63-208648.

That is, these throttle valve fully closed state detecting means are provided with a throttle opening sensor which is driven according to the movement of the throttle valve and generates a voltage signal corresponding to the opening of the throttle valve. The minimum value of the detection signal from the opening sensor is detected, and this detection value is stored and updated as a learning value. Then, the fully closed state of the throttle valve, that is, the idling operation state is determined based on the learned stored value.

In the apparatus disclosed in Japanese Patent Application Laid-Open No. 63-208648, a predetermined voltage is added to a learned value stored and updated, and the added value and a throttle opening are added. The idle state of the internal combustion engine is determined based on the comparison with the detection signal.

[0005] However, in such idle determination means,
For example, when the opening of the throttle valve is maintained from the open state in the vicinity of the memorized idle state determination voltage, the idle state is turned on and off due to a slight change in the opening degree sensor output and the power supply voltage of this sensor. Will be repeated. Also, when the throttle valve is closed suddenly, the bounce of this throttle valve repeatedly turns on and off the idle,
Accurate idle determination becomes difficult.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an opening sensor unit for judging an idling operation state of an internal combustion engine by detecting a fully closed state of a throttle valve. The throttle opening of the internal combustion engine, which is not affected by fluctuations in the output from the power supply and the power supply voltage, and enables accurate determination of the on / off state of the idle even when the throttle valve is suddenly closed. It is intended to provide a detection device.

[0007]

SUMMARY OF THE INVENTION A throttle opening detecting device for an internal combustion engine according to the present invention detects a rate of change in the opening of a throttle valve based on a detection signal from the throttle opening detecting means. Then, the rapid closing state of the throttle valve is detected based on the detected state. Further, the throttle valve is fully closed by comparing the opening signal with a predetermined set level. When the sudden close of the throttle valve is detected and the fully closed state is detected, the set level is changed to the throttle valve. To the open side.

[0008]

That is, in the throttle opening detecting device constructed as described above, in a normal operation state, the detection signal from the throttle opening detecting means is set to a predetermined set level.
In the following state, it is determined whether the throttle valve is fully closed, and whether the idle is on or off. When the opening of the throttle valve is rapidly closed, the predetermined set level is corrected to the opening side of the throttle valve. Therefore, the idling determination does not become unstable due to fluctuations in the sensor output or its power supply voltage, and especially when the throttle valve is rapidly closed, the idle determination value is corrected to the opening side of the throttle valve. Therefore, even in such a case, the determination of the idle state can be reliably performed.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration, in which a throttle valve 11 is set inside an intake passage 12 and is driven to rotate by a depression operation of an accelerator pedal (not shown), and passes through the intake passage 12 to an internal combustion engine (not shown). Controls the amount of intake air supplied.

The opening of the throttle valve 11 is detected by a throttle opening sensor 13. The throttle opening sensor 13 is composed of a variable resistor in which a contact 132, which rotates integrally with the throttle valve 11, makes sliding contact with a resistor 131 formed, for example, in an arc shape.
A voltage signal TV corresponding to the opening degree is output.

The throttle opening detection signal TV from the throttle opening sensor 13 is supplied to a fully closed output detection device 14 for the throttle valve 11. In the throttle fully closed output detection device 14, based on the throttle opening signal TV,
The output value from the opening sensor 13 when the throttle valve 11 is closed to the minimum throttle opening achievable in that state is detected and stored.

The stored output value of the opening sensor 13 corresponding to the fully-closed state of the throttle valve 11 and the opening detection signal TV from the throttle opening sensor 13 stored in the fully-closed output detecting device 14 are used to determine the idle state. Supply to device 15. The idle determination device 15 determines the idle state of the internal combustion engine based on the detection signal TV from the opening sensor 13 and the stored value of the fully closed output detection device 14.

Fully-closed output detecting device 14 for throttle valve 11
The idling determination device 15 is composed of a microcomputer.
In each of the idle determination device 15 and the idle determination device 15, the processing of the flow as shown in FIGS. 2 and 3 is executed.

First, in the fully closed output detecting device 14, FIG.
In step 101, the output voltage values TV from the 64 throttle opening sensors 13 are read every 8 ms. Then, the arithmetic mean value “TVmean” of the read output voltage value TV is calculated. When the arithmetic mean value "TVmean" is calculated in this manner, in the next step 102, the currently recorded throttle opening sensor 13 when the throttle valve 11 is fully closed is recorded.
Is determined between the output voltage value TVMIN and the arithmetic mean value TVmean.

If it is determined in step 102 that the average value TVmean is larger than the recorded value TVMIN, the process is terminated. When it is determined that TVmean is smaller than TVMIN, the routine proceeds to step 103, where the value TVmean calculated this time is stored and updated as the output value TVMIN of the throttle opening sensor 13 when the throttle valve 11 is fully closed.

FIG. 3 shows the flow of processing of the idle determination device 15. First, in step 201, it is determined whether or not a timer described later is a value smaller than "1.0 second". When it is determined that the value of the timer exceeds "1.0 second", the process proceeds to step 202, and two idle determination voltages TVIDL1 and TVIDL2 are set according to the following equation. TVIDL1 = TVMIN + DLTA1 TVIDL2 = TVMIN + DLTA2 If it is determined in step 201 that the value of the timer has not reached "1.0 second", the process proceeds to step 203 and another two idle determination voltages are obtained according to the following equation. Set TVIDL1 and TVIDL2. TVIDL1 = TVMIN + DLTA1 + DLTA3 TVIDL2 = TVMIN + DLTA2 + DLTA3 Here, the added set values DLTA1 and DLTA2 are “DL
TA1> DLTA2 ", steps 202 and 203
In each, two idle determination voltages are set,
The idle determination voltage value obtained in step 203, which proceeds before the timer value exceeds one second, is set to a value "DLTA3" higher than the idle determination voltage value obtained in step 202.

When the idle determination voltage is set in this way, the routine proceeds to the next step 204, where it is determined whether or not the determination flag XIDL indicating the idle state of the internal combustion engine is "1" (idle state). And the idle determination voltage at which the output voltage TV from the throttle opening sensor 13 is set.
It is determined whether the state is larger than TVIDL1. If it is determined in step 204 that the flag XIDL is “1” and the output voltage TV of the sensor 13 is larger than the set value TVIDL1,
Proceed to step 205 to set the idle determination flag XIDL to "0"
To clear.

In step 204, an idle determination flag is set.
If the condition that XIDL is “1” and the condition that the output voltage TV of the sensor 13 is larger than the set value TVIDL1 are not satisfied at the same time, the process proceeds to step 206. In this step 206, it is determined whether or not the condition that the idle determination flag XIDL is “0” and the output voltage TV of the opening degree sensor 13 is smaller than the idle determination voltage TVIDL2 is satisfied, and these conditions are simultaneously satisfied. If it is determined not to do so, this process ends.

When it is determined that the condition shown in step 206 is satisfied, the routine proceeds to step 207, where the idle determination flag XIDL is set to "1", and the routine proceeds to step 208.
In this step 208, the change amount ΔTV (= TV) of the output voltage value TV from the throttle opening sensor 13 every 8 ms.
_i− TV _i−1 ) is determined to be greater than or equal to the set value “DLTV”. “DLTV” is negative and greater than “DLTV”
When judged to be good, it means that the amount of change is small
When this process is terminated and it is determined that the size is smaller,
Means that the amount of change is large, and proceeds to step 209 to reset the timer. This timer is configured to always count up. After the coefficient value reaches the upper limit, the timer is held in the upper limit count state.

That is, when the idle determination flag XIDL changes from “0” to “1” in step 207,
In step 208, the amount of change ΔTV in the opening of the throttle valve 11
If it is determined that is larger, the timer is reset in step 209, and then in step 201, step 203 is selected for one second, and the idle determination voltage TVIDL1 and
TVIDL2 is set higher than the normal value by "DLTA3".

The operation as shown in FIG. 4 is performed by such processing in the idle determination device 15. First, the flag XIDL for judging the idling state is set to the set value DLTA in the output voltage value TV of the throttle opening sensor 13 in the normal state.
Two idle judgment voltages TVID which added 1 and DLTA2
LT1 and TVIDLT2 and the current output voltage TV of SENASA 13
ON and OFF are controlled in accordance with the magnitude relation of.

In this case, two idle determination voltages TVIDL1
The hysteresis is set for the operation of the idle determination flag XIDL as shown in FIG. 4 by TVIDL2 and TVIDL2. Due to such hysteresis, even when the output voltage TV of the sensor 13 is maintained in the vicinity of the idle determination voltage, the idle state does not repeatedly turn on and off unnecessarily.

If the idle determination flag XIDL changes from "0" to "1" within one second after the idle determination and the throttle valve 11 is rapidly closed, step 203 is selected in step 201. The predetermined value DLTA3 is added to each of the idle determination voltages TVIDL1 and TVIDL2 so far, and a new idle determination voltage TVID
IDL1 and TVIDL2 are set. Therefore, when such a throttle valve 11 is rapidly closed,
The bounce of 11 prevents the idle state from repeatedly turning on and off.

FIG. 5 shows another embodiment of the idle judging device 15. In this embodiment, a step 210 is added after the step 207 to the processing flow shown in FIG. . In this step 210, the idle determination flag
XIDL is than the idle determination changes to "1" from "0" throttle opening TV _i-5 for a predetermined time before, determines predetermined opening TV ₂₀ (= ₂₀ °) or more in a state of being set.

That is, in the embodiment shown in FIG. 3, when the throttle valve 11 is suddenly closed, the idle determination voltage DLTA3
In the second embodiment, a new condition for further increasing the idle determination voltage is added.

The bounce of the throttle valve 11 occurs when the throttle valve 11 is suddenly closed from a state in which the throttle valve 11 is opened to a certain extent. Therefore, by adding the condition of step 210, the bounce of the throttle valve 11 can be more reliably performed. The state can be determined. Therefore, it is possible to set a more appropriate idle determination voltage.

FIG. 6 shows a comparison between the operation of the apparatus shown in the embodiment and the operation of the conventional apparatus, in which the throttle valve 11 is rapidly closed and the output voltage from the throttle opening sensor 13 is output.
When the TV suddenly drops, the output voltage TV vibrates greatly near the fully closed output. Therefore, in the related art, the idle determination flag XIDL repeatedly changes on and off in response to the vibration of the voltage TV as shown in FIG.

On the other hand, in the embodiment, the idle determination voltages TVIDL1 and TVIDL are set within a predetermined time (one second) after the idle determination flag XIDL is set to "1".
L2 is increased by DLTA3. Therefore, even if the output voltage TV from the throttle opening sensor 13 oscillates,
The state becomes equal to or lower than the idle determination voltage TVIDL1 to which TA3 has been added, and the idle determination flag XIDL is stably set to the ON state as shown in (b).

[0029]

As described above, according to the throttle opening detecting device for an internal combustion engine according to the present invention, when detecting the idling state of the internal combustion engine, the throttle opening is normally compared with a predetermined set level. The idle state can be determined without being affected by the fluctuation of the detection signal from the sensor, and when the throttle valve is rapidly closed, the set level is corrected to the open side of the throttle valve. Therefore, the fully closed state of the throttle valve, that is, the idle state of the internal combustion engine can be accurately determined.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a throttle opening detection device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a flow of an operation of the fully-closed output detection device according to the embodiment.

FIG. 3 is a flowchart illustrating the flow of the operation of the idle determination device of the embodiment.

FIG. 4 is a diagram illustrating an idle determination state of the embodiment.

FIG. 5 is a flowchart illustrating another embodiment of the idle determination device.

FIG. 6 is a diagram for explaining an operation state of the embodiment of the present invention and a conventional example in comparison.

[Explanation of symbols]

11 ... Throttle valve, 12 ... Intake passage, 13 ... Throttle opening sensor, 14 ... Fully closed output detection device, 15 ... Idle judgment device.

Claims (1)

(57) [Claims] A throttle opening detecting means for detecting an opening signal corresponding to an opening of a throttle valve; a change rate detecting means for detecting a change rate of the opening signal; Comparing the change rate with a predetermined set value to detect a sudden closing state of the throttle valve; comparing the detected opening signal with a set level; Discriminating means for discriminating that the throttle valve is fully closed in a state below the set level, and correcting the set level to the throttle valve open side in a state in which the sudden closing of the throttle valve is detected by the sudden closing detecting means. throttle opening detecting device for an internal combustion engine, characterized by comprising a correction unit, the for.