JPH0216349A - Throttle valve opening detecting device of engine - Google Patents

Abstract

PURPOSE:To rapidly converge and stabilize a totally-enclosed learned value into a precise value by changing a learned value update request counter according to the difference between the detected value of a throttle valve and the totally-enclosed learned value, and updating the totally-enclosed learned value when the count value reaches a set value. CONSTITUTION:The throttle valve opening of an engine A is detected by a means 2. The minimum throttle opening during a sampling period which is less than a set throttle opening is detected by a means C. The minimum throttle opening is stored and updated as a throttle valve totally-enclosed value by a means D. In this device, the update of the throttle valve totally-enclosed learned value is requested by a counter E. The detected throttle valve opening in the sampling period is compared with the throttle valve totally-enclosed learned value till then by a means F. The count value of the counter E is increased/decreased according to whether the difference between them is a set value or more, or not, and also the totally-enclosed learned value is updated when the count value reaches the set value.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a throttle valve opening detection device for detecting a throttle valve opening of an engine.

(Prior art) To detect the throttle valve opening of the engine at −m,
As the basic value, it is necessary to accurately grasp the detected value when the throttle valve is fully closed.

Therefore, for example, in Japanese Patent Application Laid-Open No. 56-107926,
An invention has been proposed in which the minimum value of the output voltage of a throttle opening sensor that changes depending on the throttle valve opening (TVO) is learned and updated, and is stored, and this value is determined to be the value when the throttle valve is approximately fully closed.

(Problem to be solved by the invention) However, in actual engines, due to the effects of battery voltage fluctuations, spark noise, cranking rotation when using the starter motor, etc., the output voltage is lower than the actual output voltage when the throttle valve is fully closed. In some cases, the apparent minimum value is detected as the minimum value above, and if the minimum value above is stored as the value at full throttle and an automatic transmission is controlled based on it, the speed change will be This may cause inconveniences such as the point being shifted or the lockup not being released when necessary.

Additionally, as a device for setting the detected value when the throttle valve is fully closed, an idle switch that is turned ON when the throttle valve is fully closed is provided, and the value of the sensor output when this idle switch is activated is set as the value when the throttle valve is fully closed. has also been proposed, but such a structure first requires an idle switch and requires wiring for it, which has the drawback of increasing costs.

(Means for Solving the Problems) The present invention has been made for the purpose of solving the above problems, and includes a throttle valve opening detection means for detecting the throttle valve opening of an engine, and sampling means for detecting the minimum throttle opening during sampling 1g1 which is less than or equal to the set throttle opening based on the detected value of the valve opening detection means; In an engine throttle valve opening detection device comprising a fully closed value learning means for storing and updating the fully closed value of the throttle valve, a learning value update request counter that requests updating of the throttle valve fully closed learned value; , a throttle valve opening comparing means is provided for comparing the detected throttle valve opening of the sampling period sampled by the sampling means with the throttle valve fully closed learned value up to that point, and The count value of the learned value update request counter is incremented depending on whether the difference from the valve fully closed learned value is greater than or equal to the set value, and when the count value reaches a predetermined set count value, the throttle valve is The fully closed learning value is updated.

(Function) In the configuration of the throttle valve opening detection device for an engine according to the present invention, the throttle valve opening detected by the throttle valve opening detection means is sampled by the sampling means at every predetermined sampling period, and the sampling value is is stored and updated as the throttle fully closed learning value when a learning update request is made.

On the other hand, in that case, the throttle valve opening comparison means compares the minimum throttle valve opening within the sampling period sampled by the sampling means with the throttle valve fully closed learning value up to that point, and the difference between them is calculated as the set value. The count value of the learned value update request counter is increased or decreased depending on whether or not the learned value update request counter is greater than or equal to The new throttle valve fully closed learned value is recognized as a valid learned value and updated and stored only when the new throttle valve is fully closed.

(Effect of the invention) Therefore, according to the configuration of the throttle valve opening detection device of the present invention, in the case of erroneous learning in full throttle throttle learning, it is possible to converge to an accurate learning value as soon as possible, and the learning value Once the value becomes accurate, the learned value itself becomes stable, which in turn stabilizes the operating condition of the engine itself.

(Example) First, FIGS. 2 and 3 show the configuration and operation of an engine throttle valve opening detection device according to an embodiment of the present invention, and FIG. 2 shows the control of the device of the above embodiment. It is a flowchart which shows the throttle valve opening detection operation of the engine control unit in a system.

First, the outline of the throttle valve opening detection system of this embodiment will be explained with reference to FIG. 2, and then the control of the main parts will be explained.

In FIG. 2, reference numeral l is the engine body, and intake air is taken in from the outside via an air cleaner 30.
Thereafter, the air is supplied to each ring via an airflow meter 2 and a flow chamber 3.

Further, fuel is supplied from the fuel tank 12 to the engine side by the fuel pump 13 and injected by the fuel injector 5. The amount of air taken into the norinda during running is controlled by a throttle valve 6 provided in the throat throttle chamber 3. The throttle valve 6 is operated in conjunction with the accelerator pedal 31 via the engine control unit 9, for example, and in the idling state, the throttle valve 6 is set to the minimum opening state.
held.

The throttle valve 6 also has its opening degree (TV
A throttle opening sensor (throttle opening detecting means) 7 is provided to detect the throttle opening. This throttle opening sensor 7 is a fully closed value setting section (fully closed value setting means) of the throttle valve 6 in the engine control unit 9.
This full-open value setting section and the throttle opening sensor 7 constitute a comprehensive throttle valve opening detection device. The fully open value setting section updates and stores the minimum value of the sampling values detected by the throttle opening sensor 7 within a predetermined zumbling period, and sets that value as the value when the throttle valve 6 is fully open (fully closed value). On the other hand, the detected value (sampling value) of the throttle opening sensor 7 is compared with the previously stored value (learning value) by the throttle opening comparing means, and the count value of the learning value update request counter is determined according to the difference. is increased or decreased, and depending on the count value, a new throttle opening detection value (
A predetermined weighting is applied to the sampling value), and the result becomes a predetermined set count value, and only when the judgment evaluation is made that it is a valid learning value, the above detected value is used as a new learning value. (See Figures 1 and 3).

On the other hand, the symbol IO indicates an exhaust pipe equipped with a three-way catalytic converter 11. The exhaust pipe 10 is provided with a sensor 19 for detecting the oxygen concentration in the exhaust gas.

On the other hand, reference numeral 14 denotes an ignition plug provided in the cylinder head portion IA of the engine body 1, and a predetermined ignition voltage is applied to the I spark plug 14 via a distributor 17 and an igniter 18. It looks like this,
The application timing, that is, the ignition timing is determined by the above ECU9.
It is controlled by the ignition timing control signal 1gc supplied to the igniter 18. Furthermore, code 20
is a boost pressure sensor 20 which detects an engine boost pressure B corresponding to the engine load and inputs it to the upper ECU 9. Further, the reference numeral 16 indicates the engine cylinder blowing section I.
This is a water temperature thermistor installed in the water jacket part of B.

The ECU 9 is, for example, a microprocessor (CRU)
It consists of a memory (IROM and RAM) and an interface (Ilo) circuit. The interface circuit of this ECU 9 includes, for example, an engine starting signal (ECU trigger) from a starter switch (not shown), an engine speed detection signal NE from an engine speed sensor 15, and a water temperature thermistor 16.
Detection signal TV of cooling water 1A degrees in engine body 1 detected by 02 sensor (exhaust sensor) 19; oxygen concentration detection signal V detected by 02 sensor (exhaust sensor) 19. , various detection signals such as intake air ff1Q detected by an air flow meter are inputted. In principle, the ECU 9 determines that the actual air-fuel ratio A/F of the engine is the stoichiometric air-fuel ratio (14,7).
The above-mentioned 0.0. Based on the oxygen concentration detection signal Vo of the sensor 19, it is determined whether the oxygen concentration in the exhaust gas is excessive (excessive concentration) or lean (dilute), and the fuel from the fuel injector 5 is injected according to the determined value. It is configured to perform phytoback control of the supply amount with high precision. On the other hand, when the operating state of the bipedal engine is in a predetermined load range, the feedback control is exceptionally stopped and oven loop control is performed to a lean or ridged air-fuel ratio from the stoichiometric air-fuel ratio. There is.

Next, the throttle valve opening detection operation by the engine control unit (ECU) 9 will be described in detail with reference to the flowchart of FIG.

First, in step S, a basic timer Tn is set using the detection operation start signal as a trigger and uses the control period as a reference count value.
Increment the count value by l steps (n=n+1
)do. Next, the process proceeds to step S, where the detected opening TVO=θ(n) of the throttle opening sensor 7 shown in FIG. 2 is read.

After that, the process further proceeds to step S, and the amount by which the currently read value of the throttle opening θ(n) has changed from the previous value 0(nl) is determined by calculating the rate of change in the throttle opening 〇−θ( n) -0(n-,) is calculated.

Further, in step S4, the current throttle opening θ
It is determined whether or not (n) is smaller than the predetermined sampling judgment opening degree (initial value OO zero degree) A degree, which is the basic opening degree for taking in the learned value, and if YES, The process further proceeds to step Ss, where a predetermined sampling judgment opening change rate (absolute value) where the rate of change (absolute value) 80 of the throttle opening degree θn is the limit value for performing the learning control operation is performed.
Is it smaller than B? l+determine.

Then, if the throttle valve movement is stable (YES from the 91 constant result), the process proceeds to step S8 and a predetermined set time timer T ++ set value N (N=0.5 seconds ) is sequentially decremented (
N=N-1), and keep track of the elapsed time N.
do.

On the other hand, in step S4 above? If the determination is No at the -11 constant, the process first moves to step S7 on the other side, sets the stored value θM of the sampling opening degree to be memorized to the above-mentioned sampling judgment opening degree A, and then Proceeding to step S8, the initial jυ1 opening degree 0 (o) is changed and corrected to the above-mentioned current throttle opening degree 0 (n), and the timer T
The set value N of N is set to the initial value No, and the count value n of the n counter is reset to 0. Thereafter, the process proceeds to steps 318 to S and o, which will be described later.

By the way, when the decrement operation of the set time timer 'Ill, which is decremented in step SIl described above, is completed, the process proceeds to the next step S, and the decrement of the set value N of the counter TN is completed (N=O?). Determine the fact, and if NO, return to step S1, while if YES, proceed to step SI.
The process proceeds to step O, where the setting value of the set time timer TH is set to a predetermined initial setting value No, and then the process proceeds to step S.

In step S11, the average value θs for the sampling number No of the sampling opening degree θ within the set value period (from K-1 to NO) of the set time timer TN is = 1/N.
o・ΣOk is calculated, and the calculated value θS is used as a new sampling value (sampling opening degree) for the next step S tt
It is compared with the previous sampling opening degree storage value OM.

As a result, if YES (θS<0M), step S
At I3, the current sampling value O8 is stored and updated as a new stored value OM in place of the previously stored value θM, and furthermore, at step S14, the above-mentioned initial opening degree 0(0) is changed to θ(n
) and reset the value of the n counter to 0. on the other hand,
If NOCOs>0M) in step Sat above, it is recognized that normal learning cannot be performed, and step S
+a learning value update operation is jumped to step S14
Proceed to the operation.

Further, when proceeding from step S8 to step SI5, the sampling opening degree storage value OM up to that point is compared with the sampling judgment opening degree A described above. Then, if 0 or Δ is YES, further step S
Proceed to Ill, determine whether the difference (absolute value) between the full throttle opening/closing degree value OL and the above memorized value 77M is smaller than the predetermined tolerance value C (within the tolerance range), and select YES. If it is determined (within the allowable range), the process further proceeds to step SI7, where the count value of the learning value update request determination counter J is incremented by the corresponding one period. As a result, the determination value is added to the weighting of the learning value update request determination counter J.

On the other hand, if the determination in step S Ill is No, the process first proceeds to step S16, where the value of the learning value update request determination counter J is decremented by the corresponding one cycle to lighten the weighting evaluation, and the result is It is also determined whether the count value J has become 0 or not. If the result is YES (J-0), the value of the learned value θL of the throttle fully closed/open position is set to the memorized value (the latest memorized value) 0M, and the learned value update request determination counter J The count value of is reset to 1 (initial state @). On the other hand, if the answer is NO, the process returns to step S again.

As is clear from the above detection operation, according to the configuration of this embodiment, for example, when the change in opening of the throttle valve is stable for at least a predetermined set time N = 0.5 seconds or more, the previously learned value and the currently learned value are When the difference between the imported value and the imported value is within a predetermined tolerance, the imported value is determined to be valid, and the validity of the imported value is determined by the learned value update request determination counter ( The count value of the up/down counter) is increased or decreased according to the difference, and the count up value is set as the predetermined set value (4th
When the learned value updateable line SL) shown in the figure is reached or below, it is determined that the learning opening degree (fully closed value) is finally appropriate and is stored (see FIG. 4).

Therefore, it is possible to obtain the fully closed learning value of the throttle valve as accurately as possible in a relatively early stage and by an easy method, and stable engine control can be realized.

[Brief explanation of the drawing]

FIG. 1 is a complaint diagram of the engine throttle valve opening detection device of the present invention, FIG. 2 is a control system diagram of the device, and FIG. 3 is a flowchart of the throttle valve opening detection operation of the device. FIG. 4 is a time chart showing its action and effect. l... Engine body 2... Air flow meter 3... Throttle chamber 5... Fuel injector 6... Throttle valve 7... Throttle opening sensor 9...Engine control unit (ECU) lO...Exhaust pipe 11...Three-way catalytic converter 19...02 sensor

Claims (1)

[Claims] 1. a throttle valve opening detection means for detecting a throttle valve opening of an engine; and a sampling means for detecting a minimum throttle opening during a sampling period that is less than or equal to a set throttle opening based on a detected value of the throttle valve opening detection means. and a fully closed value learning means for storing and updating the minimum value of the throttle valve opening within the sampling period by the sampling means as a fully closed value of the throttle valve. a learned value update request counter that requests an update of the throttle valve fully closed learned value; and a comparison of the detected throttle valve opening degree of the sampling period sampled by the sampling means with the previously mentioned throttle valve fully closed learned value. and a throttle valve opening comparison means for adjusting the count value of the learning value update request counter depending on whether the difference between the detected throttle valve opening and the throttle valve fully closed learning value is greater than or equal to a set value. A throttle valve opening detection device for an engine, characterized in that the throttle valve fully closed learning value is updated when the count value reaches a predetermined set count value.