JPH0768923B2 - Engine idle speed controller - Google Patents

Description

The present invention relates to a device for controlling an engine speed (engine speed) during idle operation of an engine.

Conventionally, in this type of engine idle speed control device, the engine speed feedback control is performed under relatively stable conditions during idle operation by detecting the engine speed, throttle valve opening, etc. While performing (idle speed control), it has been proposed that the position feedback control of the throttle valve can be performed under conditions where relatively quick control is desired during idle operation.

However, in such a conventional device, the output from the sensor for detecting the opening of the throttle valve (throttle opening sensor) cannot be calibrated when the components are replaced, and therefore, When the parts are replaced in this way, there is a problem in that the control accuracy deteriorates.

The present invention is intended to solve such a problem, and uses an actuator that regulates the throttle opening degree at the time of idling based on the position feedback of the throttle valve. Is detected, under relatively stable conditions during idle operation,
While performing feedback control of the engine speed, under conditions where relatively quick control during idle operation is desired, in the idle speed control device that can perform position feedback control of the throttle valve, components were replaced due to maintenance etc. In such a case, it is an object of the present invention to provide an engine idle speed control device capable of calibrating a reference position of an actuator that defines a throttle valve opening.

Therefore, the engine idle speed control device of the present invention includes an actuator that controls the opening of a throttle valve provided in the engine intake passage, a throttle opening sensor that detects the opening of the throttle valve, and an engine idle speed controller. An idle sensor for detecting that the engine is operating and a rotation speed sensor for detecting the engine speed are provided, and a signal from the rotation speed sensor is output under the set conditions when the idle operation state is detected by the idle sensor. While feedback control of the engine speed is performed by means of the above, each of the above-mentioned conditions is provided so as to perform position feedback control of the throttle valve by a signal from the throttle opening sensor under other set conditions at the time of detecting the idle operation state. Control based on the detection signal received from the sensor Signal to the actuator, and a position sensor for detecting whether or not the actuator is at the reference position corresponding to the reference opening of the throttle valve, and detecting that the engine is stopped. Engine detection means for detecting the position of the ignition key switch, and the ignition key switch detection means for detecting the position of the ignition key switch. It is characterized in that reference position setting means for setting the actuator to the reference position based on the output of the position sensor when held at the position is provided.

An engine idle speed control device as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram thereof, and FIG. 2 is a block diagram showing the control procedure thereof, FIGS. 6 (a), 6 (b) and FIG. 7 are graphs for explaining the operation, and FIGS. 8-14 are flow charts for explaining the operation.

As shown in FIG. 1, a throttle valve 2 is arranged in an intake passage 1 of an engine E, and a shaft 2 a of the throttle valve 2 is connected to a throttle lever 3 outside the intake passage 1.

A wire for rotating the throttle valve 2 in the clockwise direction (opening direction) in FIG. 1 via the throttle lever 3 when an accelerator pedal (not shown) is depressed at the end 3a of the throttle lever 3. (Not shown) is connected, and further, the throttle valve 2 is provided with a return spring (not shown) for urging the throttle valve 2 in the closing direction, which reduces the pulling force of the wire. The throttle valve 2 is designed to close.

By the way, an actuator 4 for controlling the opening of the throttle valve 2 at the time of engine idle operation is provided, and this actuator 4 is provided with a DC motor (hereinafter simply referred to as "motor") 5 having a worm 6a on its rotating shaft. The worm 6a with the motor 5 meshes with an annular worm wheel 6b.

The worm wheel 6b is integrally provided with a pipe shaft 6c having a female screw portion 6d. The rod 7 having a male screw portion 7a screwed to the female screw portion 6d of the pipe shaft 6c is provided with the worm wheel 6b and the pipe shaft 6c. It is attached through.

The tip of the rod 7 comes into contact with the end 3a of the throttle lever 3 via the idle switch 9 as an idle sensor when the engine E is in the idle operation state.

Here, the idle switch 9 is a switch that is turned on (closed) in the engine idle operation state and turned off (open) in other states.

The rod 7 is formed with an elongated hole 7b.
A pin (not shown) on the actuator body side is guided to 7b, whereby the rotation of the rod 7 is prevented.

As described above, since the tip end of the rod 7 is in contact with the engine E when the engine E is in the idle operation state, the pipe 5c is rotated via the worm gear by rotating the motor 5 in a certain direction, and the rod 7 is rotated. When the lever is projected (moved forward) from the actuator 4, the throttle valve 2 is opened, the motor 5 is rotated in the reverse direction, and the rod 7 is retracted (retracted) into the actuator 4. It can be controlled to close by action.

A throttle opening sensor 8 for detecting the opening of the throttle valve 2 (throttle opening) is provided. As the throttle opening sensor 8, a potentiometer or the like that generates a voltage proportional to the throttle opening is used. To be

Further, a water temperature sensor 11 that detects a cooling water temperature as a warm-up temperature of the engine E is provided, and a rotation speed sensor 12 that detects an engine rotation speed by an ignition pulse is provided.

Furthermore, a vehicle speed sensor 13 for detecting the vehicle speed with a pulse signal having a frequency proportional thereto is provided, and as this vehicle speed sensor 13, a known reed switch is used.

Further, a cranking switch 14 as a cranking sensor for detecting an engine cranking state is provided. The cranking switch 14 is turned on (closed) when the starter motor is turned on, and turned off (open) otherwise. Is a switch.

Then, the control unit 15 as a control means for receiving the detection signals from the respective sensors 8, 9, 11 to 14 and outputting control signals based on these signals to the motor 5 of the actuator 4.
Is provided, but this control unit 15
Under the condition I (described later) set when the idle operation state is detected by the idle switch 9 (when the idle switch is turned on), feedback control of the engine speed (idle speed control) is performed by a signal from the rotation speed sensor 12. The position feedback control of the throttle valve 2 is performed by a signal from the throttle opening sensor 8 under another set condition II (described later) when the idle state is detected.

Here, the condition I means that at least the following items are satisfied, and the condition that the engine is relatively stable.

(1) A predetermined time has elapsed after the idle switch 9 changed from off to on.

(2) The vehicle speed is extremely low (for example, 2.5 kg / h or less).

(3) The deviation of the actual engine speed (actual speed) NR from the target speed NTW must be within a predetermined range.

(4) In a vehicle or the like having a cooler, a predetermined time has elapsed after the cooler relay or the like was switched according to the cooler load.

The condition II means a condition when the condition I is not satisfied, the engine is not relatively stable, and quick feedback control is desired.

Even if either of the above conditions I and II is satisfied, the control unit 15 does not output when it is impossible to control the throttle opening below the minimum opening or above the maximum throttle opening.

Further, the position (reference position) of the rod 7 of the actuator 4 corresponding to the reference opening of the throttle valve 2 (this opening is set as a small opening corresponding to, for example, an engine speed of about 600 rpm) is detected. A motor position switch 10 as a position sensor is provided.
That is, the motor position switch 10 is the rod 7
It is provided behind the rear end face, and is on (closed) near the state where the rod 7 is most retracted, and off (open) at other positions.
The ON / OFF signal is input to the control unit 15.

Further, as shown in FIG. 2, the control unit 15 receives an input from each of the sensors 8 to 14 and is in an engine stall mode [a mode in which the engine E is in a non-operating state (excluding a state of preparation for starting the engine)]. , Cranking mode (engine start mode) and running mode (operating modes other than the engine stall mode and cranking mode described above) are determined, and feedback control of engine speed (idle speed control) is performed or the position of the throttle valve 2 is determined. A control method for determining whether or not to perform feedback control is determined, and then the drive time of the motor 5 (including determination of the rotation direction) is calculated according to this determination result, and a control signal corresponding to this time is output to the motor 5. You can do it.

Hereinafter, the control by the control unit 15 will be described. First, the main flow for performing the main control is shown in FIG. 9, and this main flow is in principle executed in synchronization with the ignition pulse. This main flow is
When there is no ignition pulse, such as when the engine is not operating (when the engine is stalled), it is executed in synchronization with a pseudo pulse signal such as a clock having a predetermined cycle.

In addition to the main routine represented by this main flow, several routines are prepared. As this routine, a routine represented by a process flow at the time of engine stall (engine stall process flow) as shown in FIG. Engine stall, a routine fast idle represented by a processing flow at high speed idle as shown in FIG. 11 (high speed idle processing flow) and a processing flow of start at idle switch off as shown in FIG. 12 (idle switch off start processing flow ) There is a routine idle switch off start, etc., but any processing flow is executed in synchronization with a timer interrupt signal (50 ms timer interrupt signal) of a certain cycle (for example, 50 ms).

Further, these flows are time-divisionally executed, and the processing flows shown in FIGS. 10 to 12 are executed with priority over the main flow.

Now, in the main flow shown in FIG. 9, first, initialization is performed at A-0, and at A-1, the cooling water temperature TW,
Actual opening PR of throttle valve 2, actual rotational speed NR of engine E, actual vehicle speed VR, on / off information ISW from idle switch 9, on / off information MSW from motor position switch 10, on / off information CSW from cranking switch 14 Reading is done.

Then, in A-2, it is determined whether or not the actual engine speed NR <the set speed N3 (about several hundreds of revolutions),
If NR <N3, take YES route and at A-3,
It is determined whether the cranking switch 14 is on.

When the cranking switch 14 is on, the YES route is taken and the actual rotation speed NR <the set rotation speed N1 (10
(0 rotations or less) is determined. If NR <N1, it is determined that the engine is in the stalled mode (see A-6). vice versa
If NR <N1 is not satisfied, cranking mode (Refer to A-7)
Is determined.

On the other hand, when the cranking switch 14 is off, A-3
NO route is taken at and the actual speed NR <at A-5
It is determined whether or not the number of revolutions is N2 (100 revolutions or less and greater than N1). If NR <N2, YES in A-5.
Taking the route, it is determined that the engine is in the stalled mode in this case as well.

In addition, when it is determined that NR <N3 is not satisfied in A-2, or when it is determined that NR <N2 is not satisfied in A-5,
It is determined to be the traveling mode (see A-11).

That is, when the cranking switch 14 is turned on, NR <N1 (<
N2 <N3), or if the cranking switch 14 is off and NR <N2, it is determined as the engine stall mode, and if the cranking switch 14 is on and N1 ≦ NR <N3, the cranking mode is set. Is determined to be the traveling mode other than the above. As a result, the traveling mode includes not only normal traveling but also idle driving.

When it is determined that the engine is in the stalled mode in A-6, A-
In S8, the flag processing of S1 = 1 is performed. This process is a flag process related to the engine stall process flow shown in FIG. The stalling process flow will be described later.

If the cranking mode is determined in A-7, A
At -9, S1 = 0, S2 = 0 (this S2 is used for flag processing by setting S2 = 1 in the stalling processing flow)
Then, in A-10, the throttle valve target opening during cranking is calculated from the cranking map.
PTWC (this target opening changes depending on the cooling water temperature) is calculated by an interpolation method and input to the register PS.

The throttle opening (throttle valve target opening) -cooling water temperature characteristic during cranking obtained by the interpolation method is shown in FIG.

Further, when it is determined that the driving mode is A-11, in A-12, the throttle valve target opening during traveling is determined from the traveling map.
PTWD and engine target speed NTW are obtained by the interpolation method and input to registers PS and NS, and thereafter, in A-13, processing is performed to set S1 = 0 and S2 = 0 as in A-9. .

The throttle opening (throttle valve target opening) -cooling water temperature characteristic and the target rotation speed-cooling water temperature characteristic obtained by the interpolation method during traveling are shown in FIGS. 4 and 5, respectively.

In any case, the processing of A-9, A-10 and the processing of A-12, A-13 may be performed first.

After the processing of A-10 or A-13, it is determined in A-14 whether the engine cooling water temperature exceeds the set temperature for the first time. This set temperature is 0, 10, 20, ...
・ There are multiple types as shown in the table, and the set temperature is changed sequentially in relation to the actual temperature. For example, when the actual temperature is 8 ° C, the set temperature is 10 ° C, and when the actual temperature is higher than 10 ° C, the set temperature is changed to 20 ° C.

Such a determination is made in order to guarantee that the value of the register PS can be changed and accurate control can be continued even if the idle switch 9 is out of order. Details will be described later.

For this reason, if NO in A-14, the process S3 = 0 is performed in A-15 if YES, and if YES, the process S3 = 1 is performed in A-16.

After that, in A-17, it is judged whether or not the idle switch 9 is turned on. If it is turned on, in A-18, a flag process of S4 = 1 is performed, and then in A-19, the address PM of the RAM is PM. The actual opening RP is input to.

Then, in A-20, it is judged from the above conditions I and II whether or not the idle speed control is OK (possible), and if possible, in A-29, ΔN = NS in order to perform the engine speed feedback control. -NR is calculated, and if not possible, ΔP = PS-PR is calculated at A-21 to perform position feedback control.

Here, the target rotational speed NTW is entered in NS as described above, and the target opening PTWC or PTWD is entered in PS.

After the calculation of A-21 and A-29, A-22 and A-30
At, the drive time ΔD of the motor 5 is calculated from ΔP or ΔN, respectively.

Here, examples of the ΔP-ΔD characteristic and the ΔN-ΔD characteristic are as shown in FIGS. 6 (a) and 6 (b).

Furthermore, after the treatment of A-22 and A-30, A-23 and A-31
At, it is determined whether each ΔD can be set.

Here, in the case of position feedback control (A-2
In the case of 3), it is determined that it is possible if 100 ms has elapsed, for example, otherwise it is not possible. If yes, it is possible, otherwise it is impossible.

That is, the position feedback control can control every 100 ms intervals, and the engine speed feedback control can control every 700 ms intervals.

After that, at A-24, A-25, A-26, S2 = 1,
It is determined whether or not S5 = 1 and S6 = 1.
If NO, ΔD is set in the motor driving timer at A-27, and the motor is driven until the timer becomes 0 at A-28.

As a result, in both the engine speed feedback control and the position feedback control, the engine is controlled in a target state according to the cooling water temperature and the like. That is, the engine idle speed can be controlled to an optimum state.

If YES in any of A-24, A-25, and A-26, the motor drive control is not performed and the process returns.

By the way, when the idle switch 9 is off, A-17
At NO, the determination is made as to whether PS> PR at A-32. If the actual opening PR is the target opening PS
If it is smaller than (PTWC, PTWD), R at A-19
PR is input to the address PM of AM, and thereafter, the processing of A-20 to A31 is appropriately performed. As a result, even if the idle switch 9 is malfunctioning and is off, the actual opening can be controlled to the target opening even if the actual opening is smaller than the target opening, and engine stall or the like can be prevented. Never invite.

If the actual opening PR in A-32 is greater than or equal to the target opening PS, it is determined in A-33 whether S4 = 0.

If the idle switch 9 has not been turned on even once due to a failure or the like, the process of A-18 (the process of setting S4 = 1) is not performed, so S4 = 0, and in this case, A-
34, the cooling water temperature (70
It is judged whether the temperature is lower than 110 ° C.), and if it is lower, the flag processing of S5 = 1 is performed in A-38. This process is a flag process related to the idle switch off-start process flow shown in FIG. The idle switch off-start processing flow will be described later.

If S4 = 1 or if S4 = 0 but the cooling water temperature is higher than the water temperature during normal traveling, it is determined in A-35 whether S3 = 1. If S3 = 1, that is, the set temperature is exceeded for the first time (see A-14 and A-16), a flag process of S6 = 1 is performed in A-36. This process is a flag process related to the high speed idle process flow shown in FIG. The high speed idle processing flow will be described later.

When S3 = 0, that is, when the set temperature is not exceeded for the first time (see A-14 and A-15), in A-37,
The process of setting ΔP = 0 is performed, whereby the motor 5 is not driven and the rod 7 holds the current position.

In this way, A-8 (processing for setting S1 = 1), A-36
(S6 = 1 process), A-37 (ΔP = 0 process) and A-38 (S5 = 1 process) are performed, and then the process is returned.

The main flow starts the process of A-1 for each ignition pulse (including a pseudo pulse signal; the same applies hereinafter), and, for one ignition pulse, from A-1 until the next ignition pulse is output. Appropriate processing up to A-38 is performed only once, and thereafter, it is in a waiting state at the return processing.

That is, when a certain ignition pulse is input, the process of the main flow is performed only once, and the process returns to the waiting state at the return process, and when the next ignition pulse is input, A
Start from -1 processing and wait at the return processing.
The same processing is repeated thereafter.

Therefore, even if a certain ignition pulse is input, it may not be possible to set ΔD, and in this case, the rod 7 is not driven. Therefore, the position of the rod 7 is actually changed every several ignition pulses. Next, the engine stall processing flow shown in FIG. 10 will be described.

This flow is after the engine key is turned on and if this key is held in the ignition position for a certain time T0 or more,
This is a flow in which the rod 7 is retracted so that it is located at the reference position. When the predetermined time T0 has not elapsed, the engine is considered to be in the engine starting preparation state, and the cranking control is performed.

First, in B-0, it is determined whether or not S1 = 1. However, if it is determined in A-6 of the main flow that the engine is in the stalled mode, in this case, in S-8, S1 = 1 is set. When this stalling process flow is started at this time, YES route is taken in B-0.

Then, in B-1, a count process of T = T + 1 is performed, and in B-2, it is determined whether T> T0. Normally, this T0 is set to a time sufficient to be judged as an engine stall.

If T> T0, it is determined in B-3 whether S7 = 1. Since S7 = 0 at first, the process of S2 = 1 is performed in B-4, and then it is determined in B-5 whether the motor position switch 10 is on.

Normally, the rod 7 is located in front of the motor position switch 10 and the motor position switch 10 is in the OFF state. Therefore, the NO route is taken at B-5, which causes the motor at pulse width L1 at B-7. 5 is driven to drive the rod 7 backward. The retreat width at this time is determined by the pulse width L1, but this width is set relatively large.

After the processing of B-7, it returns and enters the waiting state.
The next 50 ms timer interrupt signal causes B-0 processing to be performed again. When the motor position switch 10 is off in the stalled state, B-0, B-1, B-2, B-3, B-4, B-5, B-7
The rod 7 retreats with a predetermined width by repeating the above and returning several times every 50 ms. When the motor position switch 10 is turned on by the rod 7 moving backward in this way, the route is switched to the YES route at B-5, and the process of S7 = 1 is performed at B-6, and then B-8. At, it is determined whether the motor position switch 10 is off.

In this case, since the motor position switch 10 is on, the NO route is taken and the pulse width L2 (<
L1) drives the motor 5 to drive the rod 7 forward.

The advance width at this time is determined by the pulse width L2, but this width is set to be relatively small.

After the processing of B-9, the process returns and enters the waiting state, but the processing of B-0 is performed again by the next 50ms timer interrupt signal. In this case, since S7 = 1 in B-6, , B
At -3, the process jumps to B-8, and then the process of B-9 is performed.

In this way, when the motor position switch 10 is turned off by gradually moving the rod 7 forward every 50 ms, the YES route is taken in B-8, and the B-10, B-1
In 1 and B-12, the processing of S1 = 0, S2 = 0, and S7 = 0 is performed one after another.

At this time, the rod 7 first moves backward rapidly, then slowly advances slightly and then stops.

This stops the rod 7, but this position becomes the reference position of the actuator 4 corresponding to the reference opening of the throttle valve 2. Therefore, even if the constituent parts of the present device such as the throttle opening sensor 8 are replaced after that, the output from the throttle opening sensor 8 can be calibrated at the above-mentioned reference position, and the idle screw or the like can be calibrated. It is also possible to adjust the engine speed to a desired value, and control accuracy is not degraded.

By the way, in B-2 of FIG. 10, when T> T0 is not satisfied, that is, when the engine may be in the starting quasi-state, in the same manner as A-10, in B-13, the throttle valve during cranking from the cranking map is used. The target opening PTWC is obtained by the interpolation method and input to the register PS.

The throttle opening characteristic thus obtained by the interpolation method is as shown in FIG.

Then, at B-14, it is determined whether the idle switch 9 is on. Since it is normally on, the process of S4 = 1 is performed in B-15, and then in B-16,
Input the actual opening PR to the RAM address PM.

Further, in B-17, the calculation ΔP = PS-PR is performed. Here, PS contains the target opening PTWC.

After the calculation of B-17, the driving time ΔD of the motor 5 is calculated from ΔP at B-18.

Further, after the processing of B-18, it is determined in B-19 whether ΔD can be set, that is, whether 100 ms has elapsed, for example, and if it can be set, S5 = 1 in B-20.
If it is determined that S5 = 0, in B-21, ΔD
Is set in the motor driving timer, and then the motor is driven in B-22 until the timer becomes zero.

As a result, when the engine is started, the throttle opening can be set at a desired position by the position feedback control.

By the way, when the idle switch 9 is out of order, the NO route is taken at B-14, but then the B-
At 23, the target opening PS> the actual opening PR is compared,
If PS> PR, B-16 to B-
22 processes are performed. On the other hand, if PS> PR, then B-
At 24, it is determined whether or not S4 = 0. If the idle switch 9 has not been turned on even once, S4 = 0. Therefore, at B-25, is the cooling water temperature lower than the normal running water temperature? It is judged whether or not.

And if the cooling water temperature is lower than the normal running water temperature,
At B-27, a flag process (S5 = 1) for the idle switch off-start process flow is performed.

When it is determined in B-24 that S4 = 1 or when the cooling water temperature is equal to or higher than the water temperature during normal traveling, a process of setting ΔP = 0 in B-26 is performed, and in this case, the motor 5
Is not driven and the rod 7 holds the current position.

When the rod 7 is at the reference position, S1 = 0 is set at B-10, so after that, the NO route is taken at B-0 and the reset process is performed at T = 0 at B-28. Will be returned.

Here, a schematic flow of the engine stall processing flow shown in FIG. 10 is shown in FIG. In other words, if the key switch is on and the time when the key switch is not in the starter position (in the ignition position) continues for T0 seconds or more, the rod 7
Is driven backwards to the motor position switch position,
It is set to the reference position. On the other hand, even when the key switch is in the ignition position, the cranking control is performed when T0 has not elapsed after the key switch is turned on or when the key switch is in the starter position.

Next, the high speed idle processing flow shown in FIG. 11 will be described. This flow is performed even when the idle switch 9 remains off due to a contact failure, a disconnection, or other failure.
As shown in FIG. 7, each time the cooling water temperature reaches a discretely set temperature (for example, 0, 20, 30 ° C. in the above-mentioned example), although it is rough, the target opening depends on the cooling water temperature. Degree PTWC
Alternatively, the flow is such that the PTWD can be changed.

That is, it is first determined whether or not S6 = 1 at C-0, but if S3 = 1 at A-35 of the main flow, that is, if the cooling water temperature exceeds the set temperature for the first time, at A-36,
Since S6 = 1 is set, if the high speed idle processing flow is started at this time, the YES route is taken in C-0. On the contrary, if it is not the above situation, the NO route is taken, the process is returned immediately after that, and the system waits until the next 50ms timer interrupt signal is input.

If you take YES route in C-0, in C-1,
The calculation ΔP = PS-PM is performed. Here, PS is the target opening and PM is the previous target opening.

Then, in C-2, the motor drive time ΔD is calculated from ΔP, and in C-3, it is determined whether ΔD can be set, that is, whether 100 ms has elapsed. If possible, in C-4, the RAM address is set. PS is input to PM, ΔD is set in the motor driving timer at C-5, and then the motor 5 is driven at C-6 until the timer becomes 0.

After that, in C-7, return with S6 = 0,
It waits until the next 50ms timer interrupt signal is input.

That is, in the flow shown in FIG. 11, even if the idle switch 9 fails and remains off,
Although rough as indicated by a symbol a in the figure, C-1 to C-
By the processing of 6, the motor 5 can be driven to change the target opening degree of the rod 7 according to the cooling water temperature. As a result, even when the idle switch 9 which cannot control the idle speed is out of order, the engine can be started in the cold state, and the cooling water temperature rises.
High-speed idle control that does not cause engine stall is possible. Reference numeral b in FIG. 7 indicates a target opening characteristic corresponding to the characteristics shown in FIGS.

Next, the idle switch off-start processing flow shown in FIG. 12 will be described. This flow is such that when the idle switch has never been turned on once (possibly when the idle switch 9 has failed), the actual opening PR ≧ the target opening PS and the cooling water temperature is low. Even in such a case, the flow is such that the engine E can be surely started.

That is, in this flow, first at D-0, S5 =
It is determined whether or not it is 1, but under the above conditions (conditions that satisfy idle switch off, PR ≧ PS and low cooling water temperature, hereinafter referred to as idle switch off start condition), In A-38 of FIG. 9, the process of S5 = 1 is performed. Therefore, under the idle switch off-start condition, the YES route is taken at D-0, and conversely, when the idle switch off-start condition is not satisfied, Take the NO route and return to the next
It waits until the 50ms timer interrupt signal is input.

After taking the YES route at D-0, at S-1 at D-1
= 1 is determined. At first S8 = 0, so
At D-2, it is determined whether the motor position switch 10 is on.

Normally, the rod 7 is in front of the motor position switch 10 and is in the OFF state, so at D-3
It is determined whether S9 = 1. Since S9 = 0 at the beginning, at D-17, the motor 5 is driven with the pulse width L1 to drive the rod 7 backward.

The pulse width L1 is set relatively large as described above.

After the processing of D-17, the processing is returned, and when the next 50 ms timer interrupt signal is input, the processing of D-0 and D-1 is performed again, but at this time, the motor position switch 10 is still off. Then, the rod 7 is further retracted through D-3 and D-17 again. After that, do the same with the motor position switch.
Retract rod 7 until 10 turns on.

When the motor position switch 10 is turned on, D
At S-4, the process of S8 = 1 is performed, and at D-5, it is determined whether or not the motor position switch 10 is off. At this time, since the motor position switch 10 is on, at D-6, the pulse width is set. The motor 5 is driven by L2 (<L1) to drive the rod 7 forward. Here, since the pulse width L2 is set to be relatively small, the advance degree of the rod 7 is small. After this processing, it returns and when the next 50ms timer interrupt signal is input, D-
The following processing is performed with 0, D-1. In this case, S8 in D-4
Since = 1 is set, the process jumps to D-5 at D-1, and then the processes of D-5 and D-6 are performed.

In this manner, the motor position switch 10 is turned off as the rod 7 gradually advances. As a result, the rod 7 takes the reference position. When the motor position switch 10 is turned off in this way, the YES route is taken at D-5, and the processes S7 = 0, S9 = 1, S4 = 1 are performed at D-7, D-8, D-9, respectively. Also, D
At -10, the operation ΔP = PS-PO is performed. Here, PS is the target opening and PO is the reference opening at the reference position of the rod 7.

After that, at D-11, the value of PS is input to the RAM address PM, and at D-12, from ΔP to the motor drive time Δ.
After D is calculated, it is determined whether or not ΔD can be set at D-13, that is, whether 100 ms has elapsed, and if it is not possible, the process returns and waits. After returning in this way, S9 at D-8
Since the processing to set = 1 is made, the next 50ms timer interrupt signal is input, D-0, D-1, D-2, D-3, D-10, D-
Processing from 11, D-12, D-13 is performed. When 100 ms has elapsed and .DELTA.D can be set, .DELTA.D is set in the motor driving timer in D-14, and the motor 5 is driven in D-15 until the timer becomes zero. . As a result, even under the idle switch off-start condition, the rod 7 can be quickly returned to the reference position and then set to a predetermined target opening position by position feedback control, so that the engine E can be smoothly started and accurately controlled. And are secured.

In addition, after the processing of D-15, the processing of setting S5 = 0 is performed in D-16, which causes the flow to be changed to D-
Repeat 0 and return every 50 ms.

Therefore, the following engine operation becomes possible by the flow shown in FIG. 9, FIG. 11 and FIG. That is, the engine E can be started by the flow shown in FIG. 12 even when the idle switch 9 has failed or the like and is maintained in the off state. Since the process of setting S4 = 1 in D-9 is performed, the NO route is selected in A-33 of FIG.
If S3 = 1, that is, if the target temperature is exceeded for the first time and the target opening is desired to be reduced, the throttle opening is reduced by a predetermined amount by the processing shown in FIG.

At this time, the actual opening PR is usually less than or equal to the target opening PS due to overshooting (see symbol c in FIG. 7), but if PS> PR in this way, then in A-32 in FIG. Take the YES route, and after that, by the processing of A-19 to A-31,
The actual opening PR is adjusted so as to match the target opening PS (see symbol d in FIG. 7).

In this way, the present device can perform the engine speed feedback control or the position feedback control of the throttle valve 2, and also when the engine is not operating, the rod 7 is set to the reference position and the idle switch 9 is broken. It is possible to ensure a smooth start of the engine E and to perform high-speed idle control thereafter, but in addition, it has the following fail-safe function. That is, when the throttle opening sensor 8 is out of order (when the throttle opening sensor output is almost 0)
Even if the motor 5 is driven forward, the throttle opening sensor output is still 0, so the control may run away. Therefore, in such a case, the motor 5 is driven to retract the rod 7 to the motor position switch position (reference position), and thereafter the motor 5 is not driven at all so that the fail-safe function is exhibited.
The flow is as shown in FIG. 13. In this flow, first, at E-0, an input similar to that of A-1 in FIG. 9 is read.

Then, at E-1, the throttle opening sensor output (actual opening) PR is compared with a small value Pmin close to 0,
If PR <Pmin, that is, if the throttle opening sensor output has failed and is almost 0, it is determined at E-2 whether S10 = 1. Initially, S10 = 0, so at E-3, the motor position switch 10
Is turned on.

Normally, the rod 7 is located in front of the motor position switch 10 and is in the OFF state. Therefore, at E-7, the motor 5 is driven with the pulse width L1 to drive the rod 7 backward.

The pulse width L1 is set relatively large as described above.

After the processing of E-7, the process is returned and the processing of E-0, E-1, E-2 is performed again by the input of the next ignition pulse signal, but at this time, the motor position switch 10 is still off. Then, the rod 7 is further retracted through E-3 and E-7 again. After that, do the same with the motor position switch 10
The rod 7 is retracted until is turned on.

Then, when the motor position switch 10 is turned on, E
At S-4, the process of S10 = 1 is performed, and at E-5, it is determined whether the motor position switch 10 is off. At this time, since the motor position switch 10 is on, at E-6, a pulse is generated. Width L2 (<L1)
Drive the motor 5 to drive the rod 7 forward.
Since the pulse width L2 is set relatively small here,
The degree of advancement of the rod 7 is small. After this processing, it is returned and E-0, E- is input again by the input of the next ignition pulse signal.
The subsequent processing is performed as 1, but in this case, S10 = 1 in E-4.
Therefore, at E-2, the process jumps to E-5, and thereafter E-5 and E-6 are processed.

In this manner, the motor position switch 10 is turned off as the rod 7 gradually advances. As a result, the rod 7 takes the reference position. In this way, when the motor position switch 10 is turned off and the rod 7 takes the reference position, the rod 7 is not driven at all thereafter.

If the throttle opening sensor 8 is normal, E
At -1, take the NO route, then E-7 '
Then, reset processing is performed to set S10 = 0, and position feedback control as described in detail above, that is, E-
Control is performed such that the processes shown in 8, E-9, E-10, and E-11 are sequentially performed, and this makes it possible to perform optimum idle speed control according to the engine operating state.

By the way, as an example of such a fail-safe function,
The one shown in FIG. 14 is also conceivable. Ie this first
In the flow shown in FIG. 14, if the throttle opening sensor 8 fails, the position feedback control is abandoned, but the engine speed feedback control is enabled. This flow will be briefly described. In this flow, first in F-0, FIG.
Read input that is almost the same as 1.

Then, in E-1, it is determined whether the cranking (starting) mode is the traveling mode (including the engine idle operation state). If it is the cranking mode, F-
After the process of 2, the judgment of the prospect control (F-6) or the position feedback control (F-7) is made at F-4.

If the vehicle is in the traveling mode, the processing of F-3 is performed, and then F
At -5, it is judged whether the expected control (F-8), the engine speed feedback control (F-9) or the position feedback control (F-7).

Here, the expected control means the following control. That is, under certain operating conditions of the engine, for example, the throttle valve 2
In the case where the valve closes suddenly, the rod 7 is moved forward to a predetermined position (the throttle opening corresponding to this position is called the dashpot opening) in order to gradually decrease the throttle valve opening. This is the control that is performed. By doing so, the throttle valve 2 can be gradually decreased from the dashpot opening to the desired opening as the throttle valve is rapidly closed.

When the control method is determined to be the prospective control or the position feedback control (F-6 to F-8), the throttle opening sensor output (actual opening) PR is a small value close to 0 at F-10. If it is compared with Pmin and if PR <Pmin, that is, if the throttle opening sensor output is out of order due to a failure, it is determined in F-11 whether S11 = 1. Since S11 = 0 at the beginning, it is determined at F-12 whether the motor position switch 10 is on.

Normally, the rod 7 is located in front of the motor position switch 10 and is in the OFF state. Therefore, in F-13, the motor 5 is driven with the pulse width L1 to drive the rod 7 backward.

The pulse width L1 is set relatively large as described above.

After the processing of F-13, the process is returned, and the appropriate processing of F-0 to F-11 is performed again by the input of the next ignition pulse signal, but at this time, the motor position switch 10
If is off, go through F-12 and F-13 again, then rod 7
Is further retracted. Thereafter, similarly, the rod 7 is retracted until the motor position switch 10 is turned on.

When the motor position switch 10 is turned on, F
At -14, the process of S11 = 1 is performed, and at F-15, it is determined whether or not the motor position switch 10 is off. At this time, since the motor position switch 10 is on, at F-16, the pulse width is The motor 5 is driven by L2 (<L1) to drive the rod 7 forward. Here, since the pulse width L2 is set to be relatively small, the advance degree of the rod 7 is small. After this processing, the flow is returned and the next ignition pulse signal is input, so that F-0 to F-
Appropriate processing following 11 is performed, but in this case F-14
Since S11 is set to 1, the process jumps to F-15 at F-11, and then the processes of F-15 and F-16 are performed.

In this manner, the motor position switch 10 is turned off as the rod 7 gradually advances. As a result, the rod 7 takes the reference position. In this way, when the motor position switch 10 is turned off and the rod 7 takes the reference position, the rod 7 is not driven at all thereafter.

If the throttle opening sensor 8 is normal, F
At -10, take the NO route, then at F-17
By performing the reset process to set S11 = 0, the control described in detail above, that is, the process of sequentially performing the processes shown in F-18 and F-19, is performed. This enables optimum idle speed control.

In addition, the control method is rotation speed feedback control (F-9).
If it is determined that, regardless of the output state of the slot opening sensor 8, the processing of F-18 and F-19 is performed thereafter.
That is, the idle speed control is carried out.

As described above, in the flow shown in FIG. 14, even if the throttle opening sensor 8 fails, the engine speed feedback control is guaranteed.

In addition, in FIG. 13 and FIG. 14, after the start,
Initialization processing is performed with S10 = 0 and S11 = 0. And
When the engine key is on, the flow processing is repeatedly started from the processing of E-0 and F-0 each time the ignition pulse signal is input.

Further, the present apparatus can be applied to an engine having a carburetor type fuel supply system and an engine having an injector type fuel supply system.

As described in detail above, according to the engine idle speed control device of the present invention, the following effects and advantages are obtained.

(1) When checking whether or not the engine is properly installed after replacing the components of the idle speed control device for maintenance or the like, normal engine starting operation is not performed, that is, the engine is stopped. For a certain period of time and being held in the ignition position for a certain period of time (the normal engine start operation is that the ignition key is once in the ignition position, but the engine will start immediately after entering the start position). By setting to the reference position, the reference position of the actuator that regulates the opening of the throttle valve can be obtained without starting the engine. Can be adjusted to, or the output from the throttle opening sensor can be calibrated. Come, there is an advantage that can easily improve the control accuracy.

(2) Since the above-described calibration operation can be performed when the engine is not operating, it is possible to avoid any adverse effects caused by calibrating the engine while the engine is operating, such as a sharp decrease in engine speed and an engine stop. be able to.

(3) Generally, the actuator is driven so as to match the engine required characteristics during and after the engine start preparation, and thus a special input signal is required to obtain the reference position. , The control unit can be simplified because no special input signal is required.

(4) By setting the actuator to the reference position as in (1) above, for example, the reference position of the actuator is compared with the throttle sensor output at that time, and the throttle sensor output is initially corrected or readjusted. By setting the actuator to the reference position and then disabling the actuator and starting the engine, the initial adjustment of the engine speed with the throttle opening in the fixed position without being affected by the actuator (that is, Adjustment with the idle adjustment screw) can be performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an engine idle speed control device as an embodiment of the present invention. FIG.
The figure is a block diagram showing the control procedure, FIGS. 3 to 5, and FIG.
7A and 7B and FIG. 7 are graphs for explaining the operation, and FIGS. 8 to 14 are flow charts for explaining the operation. 1 ... Engine intake passage, 2 ... Throttle valve, 2a ...
Shaft, 3 ... Throttle lever, 3a ... Throttle lever end, 4 ... Actuator, 5 ... Motor, 6a ... Worm, 6b ... Worm wheel, 6c ... Pipe shaft, 6d
...... Female thread, 7 …… Rod, 7a …… Male thread, 7b ……
Slotted hole, 8 ... Throttle opening sensor, 9 ... Idle switch (idle sensor), 10 ... Motor position switch (position sensor), 11 ... Water temperature sensor, 12 ...
… Rotation speed sensor, 13 …… Vehicle speed sensor, 14 …… Cranking switch (cranking sensor), 15 …… Control unit as control means, E …… Engine.

Continuation of front page (56) Reference JP-A-54-132019 (JP, A) JP-A-56-107926 (JP, A) JP-A-53-105639 (JP, A)

Claims (1)

[Claims] 1. An actuator for controlling the opening of a throttle valve provided in an engine intake passage, a throttle opening sensor for detecting the opening of the throttle valve, and an idle for detecting that the engine is in an idle state. A sensor and a rotation speed sensor for detecting the engine rotation speed are provided, and feedback control of the engine rotation speed is performed by a signal from the rotation speed sensor under a set condition when the idle operation state is detected by the idle sensor. On the other hand, under other set conditions at the time of detecting the idle operation state, in order to perform the position feedback control of the throttle valve by the signal from the throttle opening sensor, the detection signals from the respective sensors are received and detected. Controller that outputs a control signal based on the signal to the actuator A position sensor for detecting whether or not the actuator is at a reference position corresponding to the reference opening of the throttle valve, an engine stop detecting means for detecting that the engine is stopped, and an ignition key. The ignition key switch detection means for detecting the switch position is provided, and when the engine stop is detected by the engine stop detection means and the output of the ignition key switch detection means is held at the ignition position for a predetermined time or more, the position is set. An engine idle speed control device comprising: a reference position setting means for setting the actuator to a reference position based on an output of a sensor.