JPH02218843A - Idling judging device for engine - Google Patents

Abstract

PURPOSE:To prevent wrong judgment at the time of discriminating a mechanically idle state from the output of an idle switch by comparing the throttle signal output value with its output minimum value so as to update the appropriate minimum value and further comparing the updated minimum value with the above mentioned output value so as to judge the idle state. CONSTITUTION:When a mechanically idle state is judged by a discriminating means 30 from the output of an idle switch 10, the output value from a throttle sensor 9 and the minimum value of the appropriate value memorized in a storage means 32 is compared at a minimum value detecting means 31. In case the output value is judged to be more on the closing side than the minimum value, a minimum value updating means 35 updates the output minimum value with the output value inputted. On the other hand, if the state of being on the opening side continues for a specified time, the minimum value is updated with the value obtained by adding the set value to the output minimum value. The set offset value is added to the output minimum value by a setting means 36 so as to set the idle state judging relative reference value, and this reference value and the above mentioned output value are compared at a judging means 37 so as to judge the idle state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine idle switch that determines the idle state from the output signal of a throttle sensor.

[Prior art and problems to be solved by the invention] Generally,
During idle operation, the idle speed control valve (ISCV) is controlled to adjust the bypass passage area, adjust the engine speed to the set idle speed, and fix the ignition timing to a preset ignition advance angle.

Conventionally, this idle determination is performed mechanically by an idle switch, and when the idle switch is turned on, it is uniquely determined that the throttle valve is fully closed, that is, the engine is in an idle state, and the engine is controlled to idle.

By the way, the idle switch mentioned above needs to be turned on reliably when the throttle is fully open, so it is actually set to turn on at the opening before the throttle valve is fully closed (mechanically determined as the throttle being fully open). has been done.

As a result, even if you press the accelerator pedal and open the throttle valve when starting, etc., the engine speed will reach its upper limit, but the idle control will not be released until the throttle valve reaches the specified opening, and the engine will not decelerate. If you release the accelerator pedal while driving, the idle switch will go to ONL and idle control will take place even though the throttle valve is open.

Conventionally, the idle switch did not turn off even though the throttle valve was slightly open (judging the throttle to be fully closed), or the idle switch turned on before the throttle valve was fully open (but during that time The rate of variation in the area of the throttle bore is small, and the range of variation in the amount of intake air is small, so there was no significant effect on the starting acceleration performance or deceleration running.

However, in modern engines that have enlarged throttle bore diameters in order to obtain high performance and high output, the amount of intake air fluctuates greatly even with the slightest change in throttle opening. If the idle control is not released even if the engine speed is increased, or if the idle switch turns ON before the throttle valve is fully closed during deceleration driving, the idle control will be performed based on the output signal of the idle switch. Since the engine is canceled or idle control is performed, the lack of output not only deteriorates starting acceleration performance and deceleration performance, but also prevents proper air-fuel ratio control, which causes problems such as deterioration of exhaust emissions and fuel efficiency. This will also have a large effect on idle controllability.

One way to deal with this is to set the idle switch near full throttle, but this idle switch. In order to ensure the 0N10FF of the chain, there is a limit to the close distance, and the setting is severe and non-prone, so it is difficult to realize.

On the other hand, for example, in Japanese Patent Publication No. 63-154'67,
In order to detect when the throttle valve closes to the minimum achievable opening, when the output signal of the throttle sensor becomes smaller than the memorized value, the memorized value is sequentially updated with the output value of the throttle sensor mentioned above, and at this time, , a technique has been disclosed that determines that the throttle is fully open (idle state) and performs idle control.

However, this prior art only updates the stored value with the throttle sensor output value when the throttle sensor output value becomes smaller than the stored value, and the stored value is only updated to the smaller side (throttle closing side). In addition, since the memorized value is directly used as the comparison reference value for idle judgment, and this comparison reference value for idle judgment is compared with the throttle sensor output value to determine whether the throttle is fully open, the drift of the output signal of the throttle sensor can be avoided. Due to the influence of
i) Small resolution) When the vehicle is lifted up, the throttle sensor output value becomes higher than the comparison reference value for idle judgment even though the throttle is fully open, and the software cannot detect the fully open throttle state, resulting in an erroneous judgment. There is a problem.

To deal with this, an idle switch and a throttle sensor are used together, and as shown in FIG. When the throttle is on the closing side, the minimum output value THV MIN is updated with this output value THV as the minimum value of the throttle signal output value TH■, and an offset value α is added to this minimum stored value THVHIN. Idle judgment comparison reference value THVTSW (=THVHI
N + α), and this comparison reference value for idle judgment T H
The so-called software determines whether the throttle is fully open by comparing VISW and the throttle signal output value THV.
A soft idle switch could be considered.

However, in order to increase the accuracy of detecting the fully open throttle state, that is, the idle state, with this type of so-called soft idle switch, it is necessary to reduce the offset value α. If the throttle sensor output changes when the throttle is fully open due to distortion of the throttle shaft connecting the potentiometer, deflection due to negative pressure when the throttle is fully open, or drift of the throttle sensor output value mentioned above due to temperature changes, etc., for example,
As shown after the elapsed time t1 to t2 or t3 in FIG. 7, the throttle signal output value TI-IV is higher than the idle judgment comparison reference value THV [SW] even though the throttle is actually fully open. (In terms of software, there is a problem that the fully open throttle state, that is, the idle state, is not detected.

Also, for example, as after the elapsed time t4 in FIG. 7, n
oise to throttle sensor output minimum value THV HIM
If the offset value α is small, T HV > T HV l514 will always hold, and there will be an inconvenience that the idle state will not be detected even though the throttle is fully open.

Therefore, in the earlier application filed by the same applicant (Patent Application No. 1-1999), the present applicant has submitted the following:
When the idle switch is ON and the soft idle is OFF (elapsed time t1), the minimum memory value T HV HIM is slightly increased toward the throttle opening side every predetermined time TIME.
The idle determination comparison reference value T HV ISW is increased, and the throttle signal output value T when the throttle is fully open is increased.
We proposed a technique to correct ISW. However, as mentioned above, in engines with relatively large throttle bore diameters,
A large amount of output can be obtained with a small change in throttle opening, so when driving at a constant speed on flat ground, etc.
If you continue to lightly press the accelerator pedal, the throttle valve will often be kept at a small opening.

Then, as shown in FIG. 9, when the accelerator pedal is lightly depressed (elapsed time t2), the rough l-idle is temporarily turned off, but after that, when the idle switch is ON and the throttle valve is slightly opened, Comparison reference value T HV ISW for idle judgment is throttle signal output value TH
Until it becomes larger than V (elapsed time t3), the minimum memory value T
HV MIN is updated by a slight increase every predetermined time TIME, and after that, despite steady driving with the throttle valve opened at a very small opening, the soft idle becomes ONS'.
In other words, the engine is erroneously determined to be in an idle state with the throttle valve fully open.

As a result, the air-fuel ratio vJlll performance and ignition timing controllability during steady driving deteriorate, resulting in problems such as a decrease in output and deterioration of fuel efficiency.

[Object of the Invention] The present invention was made in view of the above circumstances, and is capable of accurately detecting the idle state without misjudgment, and even if the idle state is mechanically detected by the idle switch during steady driving, the idle state is detected automatically. It is an object of the present invention to provide an engine idle switch that can obtain stable output performance without shifting to control, and can improve fuel efficiency.

[Means for Solving the Problems] An engine idle switch according to the present invention includes an idle switch state determining means for determining a mechanical idle state from an output signal of the idle switch, and an idle switch state determining means that determines whether the mechanical idle state is determined by the idle switch state determining means. If it is determined,
Minimum value detection means receives a throttle signal output value of a throttle sensor indicating the throttle opening and compares this throttle signal output value with a minimum output value of the throttle signal output values stored in the storage means; If it is determined that the throttle signal output value is closer to the closing side than the minimum output value, the minimum output value is updated with the throttle signal output value, while the idle switch state determining means determines that the state is a mechanical idle state; And if the throttle signal output value continues to be on the open side compared to the idle determination comparison reference value for a predetermined period of time, the minimum output value is updated with a value obtained by adding the set value to the minimum output value, and further,
Minimum value updating means for stopping updating of the minimum output value in a mechanical idle state and when the throttle signal output value is closer to the closing side than the idle determination comparison reference value and then shifts to the opening side; a comparison reference value setting means for setting a comparison reference value for idle judgment by adding a set offset value to the minimum output value stored in the storage means; and a comparison reference value for idle judgment set by the comparison reference value setting means and the above. An idle state determining means is provided for determining an idle state by comparing the output value with a throttle signal output value.

[Function] In the above configuration, first, the mechanical idle state is determined from the output signal of the idle release state, and when the mechanical idle state is determined, the throttle signal output value of the throttle sensor indicating the throttle opening is taken in, and this The throttle signal output value is compared with the minimum output value of the throttle signal output values stored in the storage means.

If it is determined that the throttle signal output value is closer to the closing side than the minimum output value, the minimum output value is updated with the throttle signal output value, while the mechanical idle state is determined, and the throttle If the signal output value remains on the open side than the comparison reference value for idle judgment for a predetermined period of time, the value is the sum of the above minimum output value and the set value.
Update the above output minimum value.

Further, in the mechanical idle state, when the throttle signal output value is closer to the closing side than the comparison reference value for idle determination and then shifts to the opening side, the update by adding the set value of the minimum output value is stopped.

Further, a comparison reference value for idle judgment is set by adding a set offset value to the minimum output value stored in the storage means,
This comparison reference value for idle determination is compared with the throttle signal output value to determine whether the current operating state is an idle state or an idle release state.

[Embodiments of the invention] Hereinafter, the present invention will be described in detail based on the drawings.

1 to 6 show an embodiment of the present invention, FIG. 1 is a functional block diagram of the idle determination means, FIG. 2 is a schematic diagram of the engine control system, and FIG. 3 is a throttle signal output value. FIG. 4 is a flowchart showing the procedure for determining the idle state; FIG. 5 is a time chart of the idle switch output, idle determination signal, and soft idle with respect to the throttle signal output value;
FIG. 6 is a time chart when the engine is started by depressing the accelerator pedal.

(Structure) Reference numeral 1 in the figure is an engine body, and the cylinder head 1a of this engine body 1 is formed with an intake boat 1C and an exhaust boat 1d that open into the combustion chamber 1b.
An intake pipe 2 is communicated with C, and an exhaust pipe 3 is communicated with the exhaust boat 1d. Furthermore, an air cleaner 4 is installed upstream of the intake pipe 2, and this intake pipe 2
A throttle valve 5 is interposed in the middle, and an air chamber 2a is formed immediately downstream of the throttle valve 5.

Further, an air bypass passage 6 is communicated with the intake pipe 2 across the throttle valve 5, and an idle speed control valve (J3) is connected to the air bypass passage 6.
ISCV) 7 is installed.

Further, an intake air amount sensor (a hot wire air flow meter in the figure) 8 is interposed in the intake pipe 2 immediately downstream of the air cleaner 4.

Furthermore, a throttle sensor 9 and an idle switch 10 are connected to the throttle shaft 5a of the throttle valve 5. In order to ensure reliable operation, the idle switch 10 is set to 0N10FF at an opening point θ0 where the throttle valve 5 is slightly open from fully open.

Further, an injector 11 is installed in the intake pipe 2 immediately upstream of the intake boat 1C.

Moreover, on the crankshaft 1e of the engine main body 1,
On its outer periphery, there are protrusions at each predetermined crank angle, or
A crank rotor 12 having a slit is pivotally mounted, and a crank angle sensor 13 consisting of an electromagnetic pickup or the like for detecting a crank angle is provided on the outer periphery of the crank rotor 12. Further, a cooling water temperature sensor 14 is provided facing the cooling water passage 1f of the engine main body 1.

Also, the exhaust pipe 3 has 02t? Lancer 5 is coming,
A catalytic converter 16 is installed downstream thereof.

(Circuit configuration of control unit) On the other hand, reference numeral 17 is a control unit consisting of a microcomputer, etc., and this control unit 1
7 CPLI (central sieve processing unit) 18, ROM 19
, RAM 20, input interface 21, and output interface 22 are connected to each other via a path line 23.

Further, the idle switch 10 and the crank angle sensor 13 are connected to the input interface 21, as well as the intake air amount sensor 8 and the throttle sensor 9.
, a cooling water temperature sensor 14, 02 and a sensor 15 are connected via an A/D converter 24.

Further, the injector 11 and the coil 7a of the 15CV7 are connected to the output interface 22 via a drive circuit 25, and a spark plug 26 is connected via a distributor 27 and an igniter 28.

The ROM 19 stores fixed data and control programs, and the RAM 20 stores data after processing signals input to the input interface 21 and data processed by the CPU 18. be done. Furthermore, in the CPU 18, the ROM
According to the control program stored in 19, the above RA
Air-fuel ratio control based on various data stored in M20,
Performs ignition timing control and rotation speed control during idling.

(Functional Configuration of Idle Determination Means) As shown in FIG. 1, the idle determination means 29 provided in the control unit 17 includes an idle switch state determination means 30. Minimum value detection means 31, minimum value storage means 32, minimum value increase update condition determination means 33, counter means 34, minimum value update means 35, comparison reference value setting means 36
, idle state determination means 37, idle data storage means 38, and idle switch data storage means 39.

The idle switch state determining means 30 determines whether the vehicle is in a mechanical idle state based on the output signal of the idle switch 10. That is, when the idle switch 10 is ON, it is determined that the vehicle is in a mechanical idle state, and when the idle switch 10 is OFF, it is determined that the vehicle is in an idle release state.

If it is determined to be a mechanical idle state (the idle switch 10 is in the ON state), a trigger signal is output to the minimum value detection means 31, and idle switch data Al5WD^■^ is stored in the idle switch data storage means 39.
is stored as Al5WD^TA-1.

Note that the idle switch 10 is 0FFL when the throttle opening θ is greater than or equal to the predetermined opening 00, and ONL when the predetermined opening θ is less than 00. During assembly, the reliability of the 0N10FF operation and the detection error are Considering, throttle valve 5
It is set so that it is 0N10FF in the slightly open position.

The minimum value detection means 31 detects the throttle signal output value (output voltage) THV of the throttle sensor 9 when the trigger signal is output from the idle switch state determination means 30.
This output value THV and the output minimum value T of the throttle signal output value THV stored in the minimum value storage means 32 constituted by a predetermined address area of the RAM 20 are read.
Compare with HV HIM.

The minimum value increase update condition determination means 33 reads the determination result of the idle switch state determination means 30, and also reads the idle data storage means 38, which is configured in an address area different from the minimum value storage means 32 of the RAM 20.
Idle data AID, which will be described later, is stored in
ATA and the idle switch data Al5WDAT stored in the idle data switch storage means 39 constituted by another address area of the RAM 20.
Read A.

Then, the idle switch 10 is ON, the idle data A I DATA is in the idle OFF state of A I DATA = 1, and the idle switch data A
If 5WDAT^ is after the fiddle switch 10 with Al5WOAT8=1 is turned on from OFF, it is determined that the minimum output value increase update condition is satisfied, and a trigger signal is output to the counter means 34.

In addition, other conditions, for example, after it is determined that the idle switch data A [5WDATA is idle ON with Al5WD^TA=0, it is determined that the minimum output value increase update condition is not satisfied.

The counter means 34 starts counting when a trigger signal is output from the minimum value increase update condition determining means 33,
If the minimum output value increase update condition is a predetermined time TIME (for example,
TIME=1 sec) If continued, the minimum value updating means 35
Outputs the trigger signal.

In the minimum value updating means 35, the minimum value detecting means 31,
The output value T I-(V of the throttle sensor 9 is less than the minimum output value T HV 818 (T HV < T HV HI
M), the minimum output value THV MIN stored in the minimum value storage means 32 is further ffrl by the throttle signal ratio THV detected by the minimum value detection means 31 (TI-IVNIN 4- THV).

Further, in the minimum value updating means 35, the counter means 3
When the trigger signal is input from 4, that is, the idle switch 10 is ON, the idle data A I DAT
A is AIDATA-1, and the idle switch data Al5WDATA is AIS W DATA-1, and the output minimum value update condition is a predetermined time TIMEI[! When the control is performed, the lower set value HVs (for example, 1 bit: 51 lv) is added to the minimum output value THVHIN stored in the minimum value storage means 32 each time, and the result is calculated as follows (7).
Output minimum i1T HVHIN further tRsuru (T HV
HINm-T 11VHIN +T HVs).

In the comparison reference value setting means 36, the minimum value storage means 32
The minimum output value T HMIN specified in
The idle data A I DATA stored in the idle data storage means 38 is read and AID^T8=
1 When idle is off, the above output minimum value T HV
Set the first offset value A (for example, 2 to 3 bits) to HIM.
: 10 to 15a+v) and set this as the idle judgment comparison reference value T I - I V ISW (T 1 1 5 I 4 ← THVHIN + Δ).

On the other hand, the idle data A I DATA is
When ATA-0 idle is ON, the output minimum value T)
-IV MIN is set to the above first offset value A and the second offset value.
offset value B (for example, 1 to 2 bits: 5 to 101
v) and use this as the comparison reference value for idle judgment T H
Set as V Is- (THVIS ← THV old N
+A+8).

The idle state determination means 37 uses the comparison reference value TI-IV for idle determination set by the comparison reference value setting means 36.
Read IsW and use this idle judgment comparison standard 1ifi
T HV ISW and the output value THV of the throttle sensor 9 mentioned above! : Compare it, THV≦V°LI V TS
In the case of W, the current operating state is assumed to be an idle state, and the idle data Al0ATi is stored in the idle data storage means 38.
A [Stores as DATA-〇 and outputs idle switch.

Further, if THV>THV[5W(7), the current operating state is determined to be the idle release state, and the idle data A I DATA is stored in the idle data storage means 38.
Store as DATA=1 and turn off idle
Output a signal.

Further, the idle data storage means 38 stores idle data AIO^TAtfiAIDATA-0 as idle data AIO^TAtfiAIDATA-0.
Idle switch data storage means 3
9, set the idle switch data Al5WD8TA to A
Store as ISWDATA=O.

(Operation) Next, the operation of the idle determination means 29 having the above configuration will be explained according to the flowcharts shown in FIGS. 3 and 4.

: At startup: First, a procedure for updating the minimum output value T HV MIH, which is a reference when setting the idle determination comparison reference value T I-I V ISW used in idle determination, will be described.

As shown in FIG. 3, when the ignition is turned on, the control unit 17 is powered on, and first, in step 5101, the minimum output value THVHIN of the throttle sensor 9 is stored in a predetermined address area of the RAM 20,
Then, the comparison reference value T HV rsW for idle judgment is initialized with the initial value T HV INI determined in advance through experiments etc. (THVHIN=THV[Sen=T
HVINr).

Note that this initial Jul value T HV rNI is obtained from experiments, etc., and for example, the throttle signal output value T of the throttle sensor 9 when the throttle is fully opened during assembly.
I-I V and idle switch 10 turn from ON to OFF
This is the average value of the throttle signal output value THV of the throttle sensor 9 when switching to THV.

That is, immediately after the control units j to 17 are powered on, the throttle valve 5 may not be fully open, and the throttle signal output value THV of the throttle sensor 9 when the thrower 1-1 is fully closed is unclear; The signal output ft1li T HV also changes as the throttle sensor 9 deteriorates over time. Therefore, the minimum output value THV141 is set immediately after the control unit 17 is powered on.
N1 and a comparison reference value for idle determination T)-IV which is set by a predetermined offset from this output minimum value THVHIN
By initializing IsW with the initial value THVINI, the initial setting value is made clear.

Then, after step 5102, the output minimum fl T
Update HvHIN.

In step 5102, it is determined whether the idle switch 10 is ON, and if the ON state and the idle state are mechanically detected, the process proceeds to step 5103, and the OFF state, that is, the idle release state is detected automatically. If it is detected mechanically, proceed to step 5104;
AI S WDA the idle switch data Al5WO^TA stored at a predetermined address in the RAM 20
After setting TA=1, jump to step 5114.

Note that the idle switch data Al5WD^TA is the throttle signal output value TH of the throttle sensor 9.
This is data representing the transition state of V, and Al5WDAT^=
If it is 1, it indicates that the throttle signal output (fi T HV) after the idle switch 10 is turned off, and in step 5107, which will be described later, △ISW[)AT^=
When set to 0, it indicates that the throttle signal output value THV is after it is determined that the idle is ON.

For example, if the engine is started with the accelerator pedal released, the idle switch 10 is in the ON state, so the process proceeds to step 5103.

On the other hand, when the accelerator pedal is depressed to start the engine, since the idle switch 10 is in the OFF state, the process proceeds to step $114 via step 3104, and the minimum output value T HV HIN is not updated.

When the idle switch 10 is determined to be ON in step 5102 and the process proceeds to step 5103, the idle data A I stored in an address area different from the address area in which the minimum output value Tl-IVHIN of the RAM 20 is stored is stored. At the same time as reading DATA, the throttle signal output value T I-I V of the throttle sensor 9 is read and the process advances to step 5105 .

The idle data AIDATA is data representing the idle state determination result in the idle state determining means 37, and is set in step 5207 or 5209 in the idle state determination procedure described later.
In the case of AT 8-0, the idle determination result by the idle state determining means 37 indicates the idle state (idle ON), and when AI DATA = 1, it indicates the idle release state (idle 0FF). .

In step 5105, the idle data AIDAT read in step 8103 is transferred to A I DATA=
It is determined whether the AIDATA is 0 or not, and if it is in the idle state where AIDATA=O, the process proceeds to step 5107;
In the case of the idle release state with DATA=-1, the process advances to step 5110.

Note that in the case of the first time, since the idle data AIDATA is not set, step 5105 is skipped and the process proceeds to step 5107. Also, as mentioned above, if the engine is started with the accelerator pedal released, and the routine is performed for the second time or later, the idle data A IDATA
Since the IDATA=O (idle ON) is set, the process advances from step 3105 to step 5101.

In step 3107, the idle switch data Al5WD8T stored at a predetermined address in the RAM 20 is
Set A to A I 5WDA:TA=O, and proceed to step 8108.

In step 8108, the minimum output value TI-IVHIN stored in the RAM 20 and the throttle signal output value T of the throttle sensor 9 read in the above step 5103 are used.
HV,! -e comparison, THV≧TI-IVHIN (7
), the process advances to step 5114 and THV<THVH
In the case of IN, the process advances to step 5109.

When the accelerator pedal is released and the engine is started, the throttle signal output value THV of the throttle sensor 9 read in step 5103 shows the minimum value because the throttle valve is fully open, and the output is the initial value set in step 5101. Minimum value THVHIM (-THVTN
Since THV<THVHIN, the process proceeds from step 3108 to step 3109, where the minimum output value THV stored in the RAM 20 is
Update HIN with the throttle signal output rIiT HV read in step 5103 above (THV) 1184-
TI@V), and in step 5114, the counter count (direct TCOU14T rough IJ /' L/T (TC
OUNT←φ), the process returns to step 5102 (elapsed time t11 in FIG. 5).

At this point, in the idle state determination procedure, as shown in FIG. and idle data △l DATA
is read and the process advances to step 5203.

In step 5203, the idle data AI[lAT
Determine whether ^ is AI DATA=i. When the routine is executed for the first time, the above idle data ΔI DAr
Since the settings for A have not been made yet, step 5202
From step 8206, the process proceeds to step 8206.

In step 3206, the throttle signal output value THV read in step 5201 is compared with the idle determination comparison reference value T HV rsW. When the engine is started without depressing the accelerator pedal, the throttle signal output value T I-I V is less than or equal to the initial minimum output value THVHIN (=THVHTN) (THV≦
THVISW), it is determined to be in an idle state (soft idle ON), and steps 8206 to 5
Step 207 sets the idle data AiΔTA to AID Haccho and stores it at a predetermined address in the RAM 20. Step 8208 then outputs the idle release state (elapsed time tO to t11 in FIG. 5).

On the other hand, when the engine is started by depressing the accelerator pedal, the throttle signal output value THV is larger than the idle determination comparison standard mTHVIS14, which is set as the initial value (THV > T I-I V I needle). It is determined that the state is released (soft idle 0FF), and the process proceeds from step 3206 to step 5209, where the idle data A I DATA is set to A I DATA = 1 and stored at a predetermined address in the RAM 20, and then the process proceeds to step 5210, where the idle OFF signal is set. (6th
The elapsed time tO to t20 in the figure.

:During idling: Minimum output value T HV when the engine starts with the accelerator pedal released, the engine fully explodes, and shifts to idling operation (with the accelerator pedal released and the throttle fully open).
The HIM update procedure includes steps 5102 and 5103.5.
105 above) Execute the program you just created, and at this time,
Idle data A I read in step 5103
DATALtA IDATA=O(7-i'to/L1
0N), the process proceeds from step 5105 to step 5107, where the throttle signal output value THV read in step 5103 is compared with the minimum output value THVHIN stored in the RAM 20, and THV≧T.
HV) In the case of 41N, the output minimum value TI-IV old H
Proceeds to step 5114 without updating THV<
If THvHTN, proceed to step 5109, RO
Minimum output value T HV MIN stored in M20
The throttle output value T HV F read in step 5103 is updated, the process proceeds to step 5114, the counter value T C0UNT is cleared, and the process returns to step 5102 (elapsed time t11 to t12 in FIG. 5).

The idle state determination procedure at this time proceeds to step 5203 via steps 5201 and 5202 as described above, and the idle state determination procedure proceeds to step 5203 through steps 5201 and 5202.
/fiA ID ■＾ Since it is set to -0 (idle ON), steps 5203 to 52
Proceed to 05.

Step 5205'r is a comparison reference value T for idle determination.
HV 1814 is calculated from the following equation based on the minimum output value T HV HIN read in step 5202 above.

THV 18 size-TI-IVHIN +A10B
...(1) A; First offset value B: Second offset value Then, the process proceeds to step 8206, and the idle determination comparison reference value T I-I V Is calculated using the above equation (1)
- and the throttle signal output value T)-IV read in step 5201 above.

At this time, the throttle signal output value T)-IV is the minimum value of the throttle completely idle, and the first. Second offset value Δ
, B is added to set the comparison MQ value TH for idle determination.
Since VISW is below L7 (THV≦THVIsW), it is determined to be in an idle state, and the process proceeds from step 8206 to step 3207, where A is sent to idle data AIDAT.
After setting I DATA=Q, it is stored at a predetermined address in the RAM 200, and the process proceeds to step 3208, where the idle switch is output (elapsed time t11 to t1 in Fig. 5).
2).

Note that the first offset value A in the above equation (1), and
The second offset value B is determined in advance from experiments or the like and is stored in the ROM 19.

The above minimum output value T HV old N, the above offset value A,
Without adding B, the comparison standard value TH for idle judgment is used as is.
When used as VISW, throttle signal output value THV
If T HV HIM becomes 1 bit (minimum resolution) larger than the minimum output value T HV HIM due to drift, etc., it will be incorrectly determined that the idle is OFF even though the throttle valve is fully open, but the correction term in equation (1) above By adding A+8 to the minimum output value THV old H and offsetting the minimum output value THVHIN, the comparison reference value Tl-IV for idle judgment is obtained.
By using it as TS-, for example, when the throttle valve is fully closed, the throttle signal output ffl T H
Even if V becomes 1 bit (minimum resolution) larger than the minimum output value T HV HIM, the idle state is determined not to be incorrectly determined as idle OFF.

Also, according to experiments, the first offset value A is 2
~3 bit (10 to 15 mV), and the second offset value B is preferably 1 to 2 bi [(5 to 10 mV).

Also, press the accelerator pedal and press the idle switch 10.
If you start the engine with OFF, then release the accelerator pedal and shift to idling,
The opening degree of the throttle valve 5 decreases, the throttle signal output value THV shifts to the closing side, and the idle switch 10 shifts from OFF to ON.

The minimum output value update procedure at this time is the elapsed time t in FIG.
The idle switch 10 is still OFF between t20 and t21.
As mentioned above, the program goes to step 3.
Proceeding from step 102 to step 5104, the idle switch data AIS WDATA is set to Al5WD8T8=
After setting to 1, step 5114 is performed.
02, and the update of the minimum output value T)-I V HIN is stopped.

When the idle switch 10 is turned ON, the process proceeds from step 5102 to step 5103, where the throttle signal output value THV is read and the idle data A
Read I DATA from RAM20 Step 5ios
Proceed to. At this time, in the previous idle state determination procedure, the idle data A I DATA is
= 1 (idle 0FF), the process advances to step 5110.

Then, in step 5110, it is determined whether the idle switch data Al5WDATA is AISWDATA=Q. If you step on the accelerator pedal and start the engine from step 1 with the idle switch 10 in the OFF state, the idle switch data Al5WDAT8 was set to Al5WDAT^=1 in step 5104 of the previous routine, so the steps from step 3110 above are performed. Proceed to 5111 and check the count value of the counter TCOUNT
Rai>'y'J Ment Le(TCOUNT ←
TCOUNT+1).

Next, in step 5112, the count value T COUNT incremented in step 5111 is compared with the set time TIME (for example, 1 sec>), and TCOU
If NT<TIME, return to step 5102;
If TCOυNT≧TIME, the process advances to step 5113 and the minimum output value TI-IV stored in the RAM 20 is
Set value THVs (for example, l bit:
5 mv) to obtain this minimum output value T HV MI
Update N THVHIN 4-THVHIN +TH
Vs>, in step 5114 the counter counts (
Clear if T' C0UNT and step 510
2 (elapsed time t21-t22 in FIG. 6).

Then, the elapsed time t22 in FIG. 6, that is, the throttle signal output value THV is equal to the idle determination comparison reference value T H
When the value falls below V IsW, the idle data AID
■＾ is set to △108TA=O (idle ON>, so steps 5102 to 3103, 5
The process proceeds to step 3108 via 105.3107.

During the elapsed time period t22 to t23, the throttle signal output value TLIV is still greater than or equal to the minimum output value THV old N stored in the RAM2α (THV≧TI−IVHIN), so the process proceeds from step 8108 to step 5114 and then to step 5102. Return to minimum output value T I-I V
MIN is not updated.

After the elapsed time t23 in FIG. 6, the throttle signal output value THV becomes less than the minimum output value THV HIN (TH
When V<THV)IIN>, step 3102゜51
Step 5 via 03.3105.3107.3108
The process proceeds to step 109, where the minimum output value THV HIM stored in the RAM 20 is updated with the throttle signal output value THV read in step 3103, and step 5114
After that, the process returns to step 5102.

On the other hand, in the idle state determination procedure, idle data A I DATA is
= 1, so steps 5201.52
02, the process proceeds from step 5203 to step 5204, and the process proceeds to step 5202-('The read output minimum value T
Based on HVHIN, comparison reference value T H for idle judgment
Calculate VTSW from the following formula.

THVISW=THVHIN+A...
・(2) A: First A fret value Then, in step 8206, the comparison standard for idle judgment (ilTHVIsW calculated by the above equation (2) and the throttle signal output value THV read in the above step 3201)
Compare with.

Elapsed time t22 in FIG. Until then, the throttle signal output value THV is the idle judgment comparison reference value THVISW,)
: Since the temperature is also large (THV>Tf-IVIs), it is determined that the idle state is released, and the process proceeds from step 8206 to step 5209, where the idle data Δ108TA is set to AID.
ATA=1 is set and stored in the RAM 20, and the process proceeds to step 3210, where an idle OFF signal is output.

Then, at the elapsed time t22 in FIG. 6, T HV≦T
)-I V ISW and is determined to be in an idle state,
The process proceeds from step 8206 to step 5201, where the idle data AI DATA is updated to AI DATA=O, and the process proceeds to step 3208, where the idle switch is output.

Furthermore, in the routine from next time onwards (between the elapsed time t22 and t12 in FIG. 6), since the idle data A I DATA was set to A I DATA=0 in the previous routine, steps 3203 to 520
5, the idle determination comparison reference value T HV IsW is set using the formula (1), and then the process proceeds to step 8208 via steps 3206 and 3207, where an idle ON signal is output.

By the way, the throttle signal output value THV decreases with the closing operation of the throttle valve 5, and TI-IV>THVI with respect to the idle determination comparison reference value THV TSII.
Immediately after transitioning from S support to THV≦T HV IS-,
When setting the idle judgment reference value T HV ISW,
The offset value relative to the minimum output value T HV MIN is increased by a second offset value of 8, which causes the throttle signal output value TI-IV to become THV>T.
Immediately after the transition to HVISW or '3THV<THVISW, the idle OFI'', ON determination hunting is prevented.

: At start acceleration: After the start acceleration, that is, after the elapsed time t12 at J3 in the time charts of FIGS. 5 and 6, changes occur in the same way regardless of the starting state of the engine, so the time chart of FIG. I will explain based on this.

When the accelerator pedal is depressed to start and accelerate the vehicle from an idle state, the throttle signal output value THV gradually increases as the throttle valve 5 closes.

In the minimum output value update procedure, the elapsed time t1 in FIG.
2~t? 3, the throttle signal output value THV is less than or equal to the idle judgment comparison reference value THV ISW (THV
≦T HV I needle), and the idle data A I DATA stored in the RAM 20 is AIDAT^=
Since it is set to O (idle ON), step 5
102, the process proceeds to step 5107 via steps 5103 and 5105, and the idle switch data AIS W
DATA is set to AISWDATA=Q and the process proceeds to step 5108.

At this time, since the throttle signal output value THV is gradually increasing, it is greater than or equal to the minimum output value THVHIN stored in the RAM 20 (THV≧THVH[N), so the process returns from step 8108 to step 5114 and then returns to step 3102. Update of the minimum output value is canceled.

During the elapsed time period t13 to t14 in FIG. 5, the throttle signal output is +111! THV is larger than the idle judgment comparison reference value THV ISW (THV>
T! -4VISW), phyto)Li theta AI
DATA is set to A I DATA = 1 (idle 0FF), and the idle switch data Al5WDATA is set to A I S WDATA = O in the last routine.
Therefore, the process proceeds from step 5105 to step 5110 to step 5114, where the counter count (direct time COUNT is cleared and step 510
Return to 2.

Also, during start acceleration, the opening degree of the throttle valve 5 is large, so that the set opening degree θ0 is reached and the idle switch 10 is turned OFF.
When it is turned FF, the fiddle switch data Δl5WDATA is set to Δl5WDATA=1 in step 5104, and then the process proceeds to step 5114, where the count value T C0UNT of the counter is cleared, and the process returns to step 5102. Therefore, even when the idle switch 10 is OFF after the elapsed time t14 in FIG.
IN update is canceled.

On the other hand, in the idle state determination procedure at the time of starting acceleration, during the elapsed time t12 to t13 in FIG.
Since A=0 is set, step 5201
, 3202, test steps 5203 to 520
5, based on the minimum output value THVHIN1.1m read out in step 5202, the idle determination comparison reference value THV IS is set using the equation (1) above, and the process proceeds to step 3206.

During the elapsed time period t12 to t13 in FIG.
THVTSW), it is determined to be in an idle state, and the process proceeds from step 5206 to step 3207, where the idle data AIDATA is set to AIDAT8-0 and is stored in the RAM.
20, and outputs an idle ON signal in step 3208.

Then, at the time of elapsed time t13 in FIG. 5, THV>
TI-IVISW, and it is determined that the idle state is released.
The process proceeds from step 8206 to step 5209, where the idle data Δl DATA is updated to A r DATA=1, and the process proceeds to step 5210, where the idle OFF signal is output.

Furthermore, in the next and subsequent routines until M[, THv≦THVISI11, the idle data A I DATA in the previous routine is changed to A I DATA =
Since it is set to 1, the process proceeds from step 5203 to step 5204, where the idle determination comparison reference value T HV ISW is set using the formula (2) above, and the process proceeds from step 5206 to step 5209.
Proceeding to 210, the idle OFF signal is output.

It should be noted that the throttle signal output value THV increases as the throttle valve opening degree increases, and THV≦T+-+ v with respect to the idle judgment comparison reference value THV l514.
Immediately after the transition from THV to THV>THVISW, when the idle judgment comparison reference value THV [SW is set, the offset value for the minimum output value THV MIN is decreased by 8 minutes by the second offset value. However, as a result, the throttle signal output value THV becomes TH
V≦THVISll et al.T )-I V > T HV
Idle ON/OFF determination hunting immediately after transition to ISH is prevented.

On the other hand, during deceleration operation, when the accelerator pedal is released, the throttle signal output value T HV lfi R shifts toward the small value, and the idle switch 10 changes from OFF to OFF at the set opening θ0.
Become N.

In the procedure for updating the minimum output value at this time, step 510 is performed since the idle switch 10 has been turned ON.
2, proceeds to step 5103, reads the throttle signal output value THV, and reads the idle data AIDA.
The TA is read from a predetermined address in the RAM 20, and the process advances to step 5105.

At this time, since the idle data AI DATA was set to AID^8-1 (idle 0FF) in the previous idle state determination procedure, the process advances from step 5105 to step 5110. The idle switch data Al5WDAT^ at this time is A I in the previous routine.
5WDATA-1, so step 5
The process advances to step 111, and the count value T C0UNT of the counter is incremented.

Next, in step 5112, the count value T C0UNT incremented in step 5111 and the set time TIM are calculated.
If TCOUNT < T I M E, return to step 5102, TCOUNT ≧T
If rvc is set, the process goes to step 5113 and the RAM20
The minimum output value T HV stored in a predetermined address of
Add the setting value THVs to WIN to obtain the minimum output value THV
Update HIN L (THVHIN <-THVHIN
+THVS), and in step 5114 the counter is cleared (direct time tCoUN) and the process returns to step 5102 (elapsed time t15 to t17 in FIG. 5).

On the other hand, the idle state determination procedure at this time is that the idle data △l DATA was AID in the previous routine.
Since ATA-1 (phyto/L, 0FF) is set, the process proceeds from step 5203 to step 5204, and the idle determination comparison 1111fiTHV [S- is set using the formula (2) above, and the process proceeds to step 8206. .

During the elapsed time t15 to t17 in FIG. 5, the idle determination comparison ml value T set in step 5204
Since the throttle signal output value T)-IV is larger than HV ISW (THV>THVISW), it is determined that the idle state is released, and steps 8206 to 5 are performed.
Proceed to 209, set the idle data AIDATA stored in the RAM 20 to AIDATA=1,
In step 5210, an idle OFF signal is output.

At this time, as shown in the elapsed time t16 to t18 in FIG. 5, the throttle sensor 9 is activated! When the throttle is fully opened due to the effects of distortion of the throttle shaft 5a that connects the throttle shaft 5a, deflection of the throttle shaft due to negative pressure when the throttle is fully opened, or drift of the throttle signal output value THV of the throttle sensor 9 due to temperature changes, etc. The throttle sensor output value THV lifts in the throttle valve opening direction, and even though the throttle is actually fully open, the throttle signal output value THV is higher than the idle judgment comparison reference value THVIS-. , if the idle determination comparison reference value T HV ISW is kept constant, a fully open throttle state cannot be detected.

Therefore, in the present invention, the idle switch 10 is turned off.
When the mechanical idle state is detected by transitioning from ON to ON, if the 1 liter signal output value TH is higher than the idle judgment comparison reference value THVIS- (software idle release state; idle 0FF) goes through steps 5105, 3110 and 8111, 3112 of the minimum value updating procedure, and in step 5113, the minimum output value THV HIN stored in the RAM 20 is updated by adding the set value THVs every predetermined time TIME. Therefore, the idle judgment comparison reference value T is set by adding the set offset value A to the above minimum output value T HV HIM.
HV [S14 also sets the set value T every predetermined time TIME.
The throttle valve 5 is lifted up to the opening side by I-I V s, and at elapsed time t17 in FIG. As a result, even if the throttle signal output value THV when the throttle is fully open is lifted, the idle state with the throttle valve fully open can be detected by software through steps 8206 to 8208 of the idle state determination procedure.

The predetermined time TIME and the set value T HV s have been determined in advance through experiments and are stored in the ROM 19. Considering the influence of idle judgment when the throttle signal output value THV is normal, according to the experiment, T IME=1
sec, THVs -1 bit (5+av) is desirable.

Furthermore, in this embodiment, the idle determination comparison reference value T H
When setting V Is-, the minimum output value T HVHIM
The offset amount to be added to the throttle signal output value TH
V is the comparison reference value for idle judgment T I-I VISW
1. : On the other hand, in the case of T HV > T HV ISH, only the first offset value is set, and THVsTHV[S
In the case of W, a second offset value B is further added to obtain T.
HV>THVIS Bigger than the enemy's sword, T1-IV
＞THVISW and THVsT HV TS A hysteresis is formed during the mutual switching of the relationship, whereby T HV > T HV Is- and TI-IV≦TH
This prevents software idle ON/OFF determination hunting when mutually switching the relationship with the VIS.

As a result of the above, the idle determination can be made more accurately than when the output signal of the idle switch 10 is used as is, and the idle switch can be accurately obtained by almost following the full throttle.

:During steady driving: After accelerating from an idle state, when transitioning to steady driving with a slight throttle valve opening with the idle switch 10 turned ON by lightly pressing the accelerator pedal, the driver generally releases the accelerator pedal once and then presses the accelerator pedal again. Depress the accelerator pedal.

At this time, the procedure for updating the minimum output value THVHIH is that during the elapsed time t26 to t27 (accelerator pedal released state) in FIG. 5, the idle data AI DATA is set to AI DATA=Q because the idle is ON. , Step 51 via Steps 3102 and 8103
At 07, idle switch data Al5WDATA is Al
It is set to 5W AT^-〇.

Then, in order to shift to constant speed driving, when the accelerator pedal is lightly depressed and the throttle valve is held at a slight opening with the idle switch ON, first, at the elapsed time t28 in FIG.
V>THVIS-, and in step 5209 of the idle state determination procedure, the idle data A I DATA
is set to AI DATA = 1 (idle release state: idle 0FF).

Then, in the output minimum value update procedure, the idle data △I DATA is set to AID^■^=1 in the previous routine.
is set, the process proceeds from step 5105 to step 5110 via steps 5102 and 5103. Since the idle switch data Al5WD^TA was set to AISWD8 to O in the previous routine, the process jumps from step 5110 to step 5114 and proceeds to step 5102 without updating the minimum output value THV MIN. return.

Therefore, after the idle state B (soft idle ON) is determined, until the throttle signal output THV becomes less than the output minimum (iflTH・VHIN) again, or
When the idle switch 10 shifts from OFF to ON
I 5WDATA = 1-) and idle OFF
The above-mentioned minimum output value T HV MIH is not updated until the state of (A IDATA=1) is reached.

As a result, even when the accelerator pedal is lightly pressed and the idle switch 10 is turned on, the throttle valve remains in a very small state and the idle judgment comparison reference value T I-I V ISW is maintained at a constant speed on a flat ground. is prevented from shifting to the throttle opening side, and the idle release state is accurately determined. Therefore, there is no possibility of erroneous transition to idle control during steady running, and ignition timing control and air-fuel ratio controllability are improved, resulting in excellent running safety.

By the way, when the idle switch 10b<ON, the idle switch data Al5WD8TA is in the state of Al5WDAT8-1, and the elapsed time t15 to t1 in FIG.
Generally speaking, such a state is considered to be deceleration driving with the aggle pedal released, ie, a fully open throttle state. Therefore, from step 8111 onwards, the minimum output value T HV HIN is updated every predetermined time TIME, and the idle determination comparison reference value T HV l514 is slightly increased, thereby making the idle determination more appropriate.

Therefore, it is possible to prevent misjudgment caused by distortion of the throttle shaft 5a when the throttle valve is fully opened, deflection of the throttle shaft due to negative pressure, drift of the throttle signal output (ifiTHV, etc.), and to prevent the throttle valve from slightly opening when the accelerator pedal is lightly depressed and the idle switch is turned on. It is possible to prevent erroneous idle judgment during steady driving when the engine is held at a constant state.

On the other hand, the control unit 17 performs air-fuel ratio control, ignition timing control, and engine speed control during idling according to the output signal of the idling determining means 29, depending on the idling state and idle release state.

In addition, if the idle switch 10 has never turned ON after the control unit 17 has been energized,
If the output values of the thrower 1 to the throttle sensor 9 are inaccurate, or if self-diagnosis is in progress, the idle state or idle release state is determined according to the output signal of the idle switch 10.

Furthermore, in this embodiment, a case has been described in which a type of throttle sensor is used in which the output value decreases as the throttle valve opening decreases; however, the present invention is not limited to this, and the output value increases as the throttle valve opening decreases. A type of throttle sensor may be used; in this case, the directions of the inequality signs in steps 310g and 5206 in the flowchart are reversed, and the maximum output value is used instead of the minimum output value.

Furthermore, in this embodiment, an idle switch is used that is turned on when the throttle valve is opened to 0FFL, and when the throttle valve is opened from θ0. ONL on the throttle valve opening side, 6 throttle valve closing side from θ0'
An idle switch that turns C'' OFF may also be used, in which case the determination in step 5102 is reversed.

[Effects of the Invention] As explained above, according to the present invention, the idle state can be accurately detected without misjudgment, and the idle state can be mechanically detected by the idle switch during steady driving.
There is no shift to idle control, stable output performance can be obtained, and excellent effects such as improved fuel efficiency are achieved.

[Brief explanation of the drawing]

1 to 6 show one embodiment of the present invention, FIG. 1 is a functional block diagram of the idle determination means, FIG. 2 is a schematic diagram of the engine control system, and FIG. 3 is the minimum throttle signal output value. FIG. 4 is a flowchart showing the procedure for updating the value, FIG. 4 is a flowchart showing the procedure for determining the idle state, FIGS. 5 and 6 are time charts of the throttle signal output value, idle switch output, and idle determination signal. Figure 6 is a time chart of the idle switch output, idle discrimination signal, and soft idle in relation to the throttle signal output value. 9 to 9 are time charts of conventional minimum memory values for throttle signal output, comparison reference values for idle determination, and soft idle. 9... Throttle sensor, 10... Idle switch, 20... Storage means (RAM), 30... Idle switch state determination means, 31... Minimum value detection means,
35... Minimum value updating means, 36... Comparison standard value setting means, 37... Idle state determining means, A, B...
Offset value, THV... Throttle signal output value, T
HV HIM...Minimum output value, THV Is-...
- Comparison reference value for idle judgment, THVs...set value, TIME...predetermined time. Figure 4

Claims (1)

[Scope of Claims] Idle switch state determining means for determining a mechanical idle state from an output signal of an idle switch; and a throttle sensor that indicates a throttle opening when the idle switch state determining means determines a mechanical idle state. minimum value detection means that receives a throttle signal output value and compares this throttle signal output value with a minimum output value of throttle signal output values stored in a storage means; If it is determined that the output is closer to the closing side than the minimum value, the minimum output value is updated with the throttle signal output value, and the idle switch state determining means determines that the idle switch state is in the mechanical idle state, and the throttle signal output value is the idle state. If the state in which the comparison reference value for judgment is on the open side continues for a predetermined period of time, the minimum output value is updated with the value obtained by adding the set value to the minimum output value, and in addition, when the state is in a mechanical idle state and the throttle signal is minimum value updating means that stops updating the minimum output value when the output value is closer to the closing side than the comparison reference value for idle judgment and then shifts to the opening side; A comparison reference value setting means for setting a comparison reference value for idling judgment by adding the set offset value, and a comparison reference value for idling judgment set by the comparison reference value setting means and the above throttle signal output value are compared to determine idling. 1. An engine idle determination device comprising an idle state determination means for determining a state.