JP3521562B2 - Engine automatic stop / start device - Google Patents

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention
More particularly, the present invention relates to a device for automatically stopping and automatically starting an engine when a predetermined condition is satisfied in a vehicle such as an automobile.

[0001]

2. Description of the Related Art Generally, when a vehicle is driving in an urban area, it may stop at an intersection or a railroad crossing. If the engine is idled at this time, fuel is consumed and the fuel consumption rate decreases. .

Therefore, the engine is stopped when a certain condition such as the vehicle is stopped to cut off the fuel consumption during a temporary stop, and the engine is automatically restarted when a predetermined condition is satisfied thereafter. An automatic engine stopping / starting device has already been proposed.

FIG. 3 shows an example of the construction of such an engine automatic stop / start device. In the figure, reference numeral 1 denotes a vehicle speed sensor as means for detecting the vehicle speed from the rotation of a disc gear 1a attached to a wheel. Reference numeral 2 denotes an engine speed sensor as means for detecting the engine speed from the rotation of a disc gear 2a attached to the crankshaft of the engine, and 3 is clutch detection means for detecting whether or not the clutch pedal CP is depressed. Is a clutch switch, 4 is a neutral switch for detecting the neutral position of the gear by the shift lever SL, and 5 is an engine E.
A cooling water temperature sensor as a means for detecting the cooling water temperature of NG, and an air pressure sensor 6 as a means for detecting the air pressure of the air tank 10.

Reference numeral 7 is a controller, which is a sensor 1,
An input port 71 for receiving the output signals of 2, 5, and 6 and the output signals of the switches 3 and 4, and the input port 71
Of the central processing unit (hereinafter referred to as CPU) 72, which receives the output signal from the CPU 72 and is connected to the memory (RAM) 74 in accordance with a control program stored in the memory (ROM) to perform data processing. And an output port 75 for sending to the outside.

Further, 11 is an electromagnetic valve (hereinafter, simply M / V
The air from the air tank 10 is supplied to the air cylinder 12. Reference numeral 13 denotes an intake shutter for stopping the engine ENG by shutting off the intake air of the engine ENG by the air from the air cylinder 12. Reference numeral 14 is a starter motor for starting by the output signal of the output port 75.

The stop condition and the start condition in such an engine automatic stop / start device are schematically shown in FIG.

First, regarding the automatic engine stop condition, the following eight items are required as shown in FIG. The vehicle speed should be approximately 0km / h. The engine speed should be below 800 rpm, which is the actual idling speed (the speed without idling). The gear is in neutral. The clutch pedal is not depressed. The engine coolant temperature must be 40 ° C or higher. The air pressure should be 64kPa or more. A vehicle speed of 10 km / h or higher has been detected since the system was turned on. No failure was found by the failure diagnosis.

That is, when the vehicle is stopped, the engine EN
G is in idling rotation, the gear is in neutral, the clutch pedal is not depressed, the engine ENG is warm, and there is sufficient air pressure in the air tank 10 for the air cylinder 12 for automatic engine stop. The engine ENG is closed by closing the intake shutter 13 by the air cylinder 12 and closing the intake air of the engine ENG when the automatic engine stop condition is satisfied, that is, it is confirmed that the vehicle has run at least once and there is no failure. We aim to reduce exhaust gas and noise by automatically stopping the engine and eliminating unnecessary fuel consumption.

On the other hand, after the engine is automatically stopped as described above, the conditions for restarting the engine ENG are as follows: (1) The engine speed is 0 rpm. (2) Must be gear neutral. (3) The clutch is depressed. Three well-known items are required.

FIG. 5 shows a flow chart for the CPU 72 in the controller 7 to judge the automatic stop condition and the automatic start condition as described above and execute the processing, which will be described below with reference to FIG.

First, the CPU 72 determines the state of the electromagnetic valve 11 stored in the memory 74, that is, the electromagnetic valve 11 is ON.
It is determined whether (excitation state) or OFF (step S41).

As a result, the electromagnetic valve 11 is initially turned off.
Since it is in the state, the CPU 72 next also starts the starter 14
State, that is, whether the starter 14 is ON or OFF (step S42).

Here again, the starter 14 is initially OFF, so the routine proceeds to step S43, where the flag F1 is ON.
It is determined whether it is (set) or OFF (clear). Since the flag F1 is initially OFF, the process proceeds to steps S44 to S50.

These steps S44 to S50
4 respectively correspond to the conditions 1 to 4 shown in FIG. 4A, and it is determined that the automatic stop condition STC is satisfied when the determination result in each step is "Y".

Although conditions are added in FIG. 5A, this step may of course be added in the flow chart of FIG.

When all the automatic stop conditions STC based on steps S44 to S50 are satisfied in this way, the CPU 72 causes the electromagnetic valve 1 to operate via the output port 75.
1 is turned on, and the engine is automatically stopped as described above (step S51).

If any of the conditions is not satisfied in steps S44 to S50 (judgment result "N"), this routine is exited without proceeding to step S51.

When the electromagnetic valve 11 is turned on in this way, in the next cycle of this flowchart, the routine proceeds from step S41 to step S52, where the engine speed N
It is determined whether _{E is} almost 0 rpm.

That is, when the electromagnetic valve 11 is turned on in step S51 and the engine speed of the engine ENG gradually decreases, the engine speed N _E has not reached 0 rpm yet, so the routine exits from step S52. After a lapse of a fixed time, the engine speed N _E becomes almost 0 rpm and the engine is stopped. Therefore, the CPU 72 turns off the electromagnetic valve 11 (step S53), turns on the flag F1 (step S54), and exits this routine.

Therefore, in the next cycle, the process proceeds to step S43 via steps S41 and S42,
Since the flag F1 is turned on here, step S
Proceeding to 55, it is determined whether or not the gear is in neutral, and further it is determined in step S56 whether or not the clutch is in the disengaged state.

That is, after the engine speed N _E becomes approximately 0 rpm in step S52, the state of the gear and the clutch is determined in steps S55 and S56 by the automatic start condition (1) to (1) shown in FIG. 4 (b). This corresponds to (3), and the automatic start condition SPC is satisfied only when the gear is in neutral in step S55 and the clutch is in the disengaged state in step S56. The starter motor 14 is turned on via 75 to start the engine and exit this routine.

Incidentally, step S55 or step S5
If the determination result in 6 is "N", step S
This routine will exit without going through 57.

Therefore, in the processing of the next cycle, after the step S41, the starter is turned on in the step S42, so the routine proceeds to the step S58, and the engine speed N _E becomes 400 rpm (idle speed). It is determined whether or not there is.

As a result, the engine speed N _E is 400 rpm.
When the engine speed N _E reaches 400 rpm, the CPU 72 turns off the starter 14 (step S59) when the engine speed N _E reaches 400 rpm. The flag F1 is turned off (step S6
0) exit this routine.

In steps S58 to S60, after the starter 14 is turned on, it is determined whether or not the engine ENG has completed the explosion, and when the complete explosion has occurred, the starter 14 is moved to the engine E.
This is a process for disconnecting from NG.

[0026]

As described above, in the conventional engine automatic stop / start device, after the automatic stop condition is satisfied, the electromagnetic valve is energized to start the stop operation, but before the engine is stopped. In some cases, the above stop condition may not be satisfied, and even in this case, the next start condition is not accepted until the engine is completely stopped.

Therefore, when the automatic stop operation is stopped halfway, for example, when the engine shifts to an operation of immediately starting (operation of stepping on the clutch to put the gear), the engine does not want to be stopped, but after stopping. Since it will be shifted to the starting condition, there is a time delay and it is not possible to react promptly to the driver's intention.

Similarly, when the starting condition is satisfied while the engine is automatically stopped and the starter is energized to automatically start the engine, the next stopping condition is not accepted until the engine is completely detonated. ing.

Therefore, when the automatic starting operation is stopped in the middle, for example, when the driver feels that the starting operation is started but the vehicle is still stopped and the driver releases the clutch and wants to return to the stopped state again, the engine is completely exploded. After that, the stop condition is entered again, and the electromagnetic valve is energized to stop the engine, which also causes a time delay.

Therefore, according to the present invention, an engine automatic stop / start device in which the controller automatically stops the engine when a predetermined stop condition is satisfied and the controller automatically starts the engine when another predetermined start condition is satisfied. The purpose is to enable quick recovery and backup when canceling the stop / start condition.

[0031]

In order to achieve the above object, an automatic engine stop / start device according to the present invention is provided with the
The controller has determined that the stop condition or the start condition is met .
At the same time, a means to stop or start the engine is created.
When the engine detects that the stop condition or the start condition is not satisfied before the engine is stopped or started, the operation of means for stopping or starting the engine
The operation is stopped and the process is shifted to the determination of the start condition or the stop condition.

That is, in the present invention, when the automatic stop condition is satisfied, the engine is operated to be stopped, but it is monitored whether or not the above stop condition is released before the engine is stopped.

As a result, when the stop condition is not released, the engine is stopped as it is. However, when it is found that the stop condition is released, it is determined that the stop condition is not satisfied and the engine is stopped. Stop and shift to the determination of starting conditions.

If the starting condition at this time is satisfied, the engine is automatically started.

On the contrary, even when the engine is started after the automatic start condition is satisfied, it is monitored again whether or not the start condition is released. If not, the engine is automatically started as it is. When it is canceled, the engine start is stopped, the engine speed is monitored, and when the engine is in the stopped state, the automatic start condition determination is started.

In the above engine automatic stop / start device, the stop conditions are cooling water temperature detecting means, air pressure detecting means for the air cylinder for the intake shutter of the engine, vehicle speed detecting means, and engine speed detecting means. From the output signals of the clutch detecting means and the neutral detecting means, the vehicle is in a stopped state, the engine is substantially below the idle speed, the gear is in neutral, the clutch pedal is not depressed, the cooling water temperature is above a predetermined value, and the air pressure is It can be determined by the controller that the vehicle is satisfied when it is equal to or more than the predetermined value and one run can be confirmed from the vehicle speed.

Further, the starting condition can be judged by the controller from the output signals of the clutch detecting means and the neutral detecting means as being satisfied when the gear is in neutral and the clutch pedal is depressed.

[0038]

1 and 2 are flow charts of a control program executed in an engine automatic stop / start apparatus according to the present invention. As an apparatus, the engine shown in FIG. The automatic stop / start device can be applied as it is, and the flowchart of the program executed by the CPU 72 of the controller 7 in this device is shown.

The operation of the engine automatic stop / start system according to the present invention shown in FIG. 3 will be described below with reference to the flow charts of FIGS. 1 and 2.

First, the CPU 72 sets the flag F2, which will be described later, to O.
It is determined whether it is N or OFF (step S1),
Initially, the flag F2 is OFF, so the routine proceeds to step S2, where it is determined whether the electromagnetic valve (M / V) 11 is ON or OFF.

Also in this step S2, the electromagnetic valve 1
Since 1 is initially OFF, the process proceeds to step S3. Similarly, it is determined whether a flag F3 described later is ON or OFF. Since the flag F3 is initially OFF, the process proceeds to step S4 and the starter 14 is turned ON. Or OFF.

Since the starter 14 is initially OFF, the routine proceeds to step S5, where it is determined whether the flag F1 similar to the flag F1 shown in FIG. 5 is ON or OFF.

Since the flag F1 is also initially OFF, the automatic stop condition (STC) is determined in step S6.

The determination of this automatic stop condition is shown comprehensively, and the determination of these stop conditions corresponds to steps S44 to S50 shown in FIG. Needless to say, the condition shown in FIG. 4A may be included in this step S6 as in the conventional example of FIG.

Only when the automatic stop condition (STC) is completely satisfied in step S6, the electromagnetic valve 11 is turned on to execute the automatic stop operation of the engine ENG in step S7. However, even one of the automatic stop conditions is satisfied. If not, this routine is exited without executing step S7.

[0046] In this way, when the electromagnetic valve 11 the automatic stop condition is satisfied is turned ON in step S 7, in the processing of the next cycle, where operation proceeds from step S1 to the step S2, the solenoid valve 11 is Since it is ON, the process proceeds to step S8 shown in FIG.

This step S8 is also for determining the automatic stop condition (STC) corresponding to steps S44 to S50 shown in FIG. 5, like step S6 shown in FIG.
In particular, the automatic stop condition is monitored here.

That is, when the automatic stop condition continues to be completely satisfied, the routine proceeds to step S9, where it is judged whether or not the engine speed N _E has become substantially 0 rpm, and when it has not reached 0 rpm, step S1 → S2 → S8 → S9
The engine speed N
_{When E} becomes 0 rpm, the CPU 72 turns off the electromagnetic valve 11 (step S10) and turns on the flag F1 (step S11). Then exit this routine.

As a result, in the process of the next cycle, the process proceeds to steps S1 → S2 → S3 → S4 → S5. Since the flag F1 is ON in this step S5, the process proceeds to step S12 and the gear is in the neutral state. If the clutch is in the disengaged state, the process proceeds to step S13 to determine whether the clutch is in the disengaged state.

These steps S12 and S13 are shown in FIG.
The start condition SPC corresponding to steps S55 and S56 shown in FIG. 5 is determined, and the starter 14 is turned on only when the gear is in the neutral state and the clutch is in the disengaged state.
(Step S14), but otherwise, the routine of steps S1 to S5 → step S12 is repeated.

In this way, when the automatic stop condition is completely continued, the start condition is judged after waiting for the engine ENG to be completely stopped, and the starter 14 is started when the start condition is satisfied. Then, the engine ENG is automatically started.

On the other hand, in step S8 of FIG. 2, if at least one of the automatic stop conditions is not satisfied and is incomplete, the electromagnetic valve 11 is turned off in step S15, and further the flag F2 is set in step S16.
Turns ON and exits this routine.

Therefore, in the process of the next cycle, the process proceeds from step S1 in FIG. 1 to step S17 in FIG. 2, and in step S17 the engine speed N _E
Is 0 rpm, 0-400 rpm, 400 rpm
It is determined whether or not the above.

As a result of this determination, the engine speed N _E is 4
When it is found that the speed has returned to above 00 rpm, the flag F2 is turned off in step S18.

Therefore, in the processing of the next cycle, steps S1 to S6 are executed, and since the automatic stop condition is incomplete in step S6, such steps are repeated.

That is, since the engine speed is 400 rpm or more, it is not necessary to automatically stop the engine.

On the other hand, when it is determined that the engine speed N _E has become 0 rpm, the flag F2 is turned off in step S19 and the flag F1 is turned on in step S20, and this routine is exited.

As a result, in the processing of the next cycle,
Since steps S1 to S4 are executed and the flag F1 is turned on in step S5, the automatic start condition (SP) in steps S12 to S14 is set as described above.
C) will be executed.

That is, when the automatic stop condition becomes incomplete, the determination shifts to the start condition, so the starter 14 can be restarted without stopping the engine ENG.

When the engine speed N _E is 0 to 400 rpm in step S17, step S
By exiting this routine from step 17, step S1
→ The routine of S17 is repeated to wait for the engine speed N _E to gradually decrease. That is, the engine speed N _E becomes stable at either 400 rpm or 0 rpm.

Since the starter is turned on when the starting conditions in steps S12 to S14 are satisfied, after the steps S1 to S3 are executed in the process of the next cycle, the starter is turned on in step S4. Therefore, the process proceeds to step S21, it is determined whether the gear is in the neutral state, further it is determined in step S22 whether the clutch is in the disengaged state, and further it is determined whether the engine speed is approximately 0 rpm. .

That is, these steps S21 to S2
3 is performing the starting condition monitoring (SPM) process of monitoring whether or not this automatic starting condition is held even though the automatic starting condition is currently entered.

As a result, when the gear is in the neutral state, the clutch is in the disengaged state, and the starting condition is satisfied when the engine speed is approximately 0 rpm, the flag F is determined in step S24.
Turn off 1 and exit this routine.

While this starting condition is satisfied, the routine of steps S1 to S4.fwdarw.S21 to S24 is repeatedly executed.

However, if any of the determination results in the starting condition monitoring (SPM) processing in steps S21 to S23 is "N", the starter 14 is turned off in step S25 and the flag F3 is turned on in step S26. Exit this routine as.

As a result, in the process of the next cycle, the process proceeds to step S27 shown in FIG. 2 via steps S1 to S3.

This step S27 corresponds to step S17. When it is found that the engine speed N _E is 0 rpm, the flag F is set at step S28.
Turn off 3 and exit this routine.

Therefore, in the process of the next cycle, the process proceeds from step S3 to step S4, and further step S
In step S20, it is determined whether or not the flag F1 is ON. However, since the flag F1 is ON in step S20, the starting conditions (SP in steps S12 and S13) (SP
C) It will move to judgment.

That is, when the automatic start condition is broken, the starter 14 is returned to OFF, but since the engine speed N _E is 0 rpm, the automatic stop condition is tried again.

In step S27, the engine speed N
_{When E} is 0 to 400 rpm, this routine is exited as in step S17 and steps S1 to S3 are repeated until the engine speed stabilizes, but it is found that the engine speed N _E is 400 rpm or more. Occasionally, the flag F1 is turned off in step S29, and the flag F3 is turned off in step S30 to exit this routine.

As a result, when the engine speed is 400 rpm or more, the process proceeds to steps S1 to S5, and further, at step S6, the automatic stop condition (STC) is determined.

That is, if the engine speed N _E is the idle speed when the automatic start condition is broken, the automatic stop condition is about to be set.

In the above embodiment, the automatic stop / start conditions as shown in FIGS. 1 and 2 are shown, but needless to say, the present invention can be applied to various automatic stop / start conditions.

[0074]

As described above, according to the engine automatic stop / start device of the present invention, the stop condition or the start condition is arranged after the stop condition or the start condition is arranged and before the engine is stopped or started. When it is detected that is not established, it is configured to shift to the judgment of the start condition or the stop condition without stopping or starting the engine.Therefore, when the automatic stop and the automatic start condition are canceled midway, recovery and backup are required. It is possible to do it quickly and not to burden the driver.

[Brief description of drawings]

FIG. 1 is a flowchart (No. 1) of automatic stop / start processing executed by a controller used in an engine automatic stop / start apparatus according to the present invention.

FIG. 2 is a flowchart (part 2) of the automatic stop / start processing executed by the controller used in the engine automatic stop / start apparatus according to the present invention.

[Fig. 3] Automatic engine stop common to the present invention and the conventional example
It is a figure showing an example of composition of a starting device.

FIG. 4 is a block diagram for schematically explaining stop conditions and start conditions of a conventional engine automatic stop / start device.

FIG. 5 is a flowchart showing an automatic stop process executed in a controller used in a conventional engine automatic stop / start device.

[Explanation of symbols]

1 vehicle speed sensor 2 Engine speed sensor 3 clutch switch 4 Neutral switch 5 Cooling water temperature sensor 6 Air pressure sensor 7 controller 10 air tanks 11 Electromagnetic valve (M / V) 12 Air cylinder 13 Intake shutter ENG engine 14 Starter motor In the drawings, the same reference numerals indicate the same or corresponding parts.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI F02N 15/00 F02N 15/00 E (56) References JP-A-6-257483 (JP, A) JP-A-58-23254 ( JP, A) JP 59-194050 (JP, A) JP 60-162023 (JP, A) JP 60-132040 (JP, A) Actually opened 59-142435 (JP, U) Actually opened Sho 63-67636 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02D 17/00 F02D 29/02 F02N 15/00

Claims (3)

(57) [Claims] 1. An automatic engine stop / start device for causing a controller to automatically stop an engine when a predetermined stop condition is satisfied and for causing the controller to automatically start the engine when another predetermined start condition is satisfied, The controller is means for stopping or starting the engine at the same time when the stop condition or the start condition is satisfied.
Actuating the means the stop condition or the starting condition for stopping or starting the engine when it is detected that not to be established until the engine is stopped or started respectively
The automatic engine stop / start device, characterized in that the operation of (1) is stopped and the process is shifted to the determination of the start condition or the stop condition. 2. The automatic engine stop / start device according to claim 1, wherein the stop conditions are cooling water temperature detection means, air pressure detection means for an air cylinder for an engine intake shutter, vehicle speed detection means, and engine rotation. From the output signals of the number detection means, the clutch detection means, and the neutral detection means, the vehicle is in a stopped state, the engine is substantially below the idling speed, the gear is in neutral, the clutch pedal is not depressed, and the cooling water temperature is above a predetermined value. The automatic engine stop / start device, wherein the controller determines that the air pressure is satisfied when the air pressure is equal to or higher than a predetermined value and one run can be confirmed from the vehicle speed. 3. The engine automatic stop / start system according to claim 1, wherein the starting condition is that the gear is in neutral from the output signals of the clutch detecting means and the neutral detecting means and the clutch pedal is depressed. An automatic engine stop / start device characterized in that it is determined by the controller that the above condition is satisfied.