JPS58178845A - Method of controlling automatic stopping and starting of engine - Google Patents

Abstract

PURPOSE:To prevent failure of restarting an engine, by resetting the automatic engine stopping and starting function in case that the rate of slippage of an alternator has exceeded a set value required for keeping the battery charging state. CONSTITUTION:In case that an output 110 produced from a neutral point of an alternator 100, an ignition pulse signal 15 and the rate of slippage of the alternator 100 calculated on the basis of the pulley ratio pre-stored in a memory of a control circuit 1 have exceeded prescribed value, an alarm is given at a display means 80 in response to a control signal 90, and at the same time, the function for automatically stopping and starting an engine is cancelled automatically by a control circuit 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic engine stop/start control method for automatically stopping or restarting an engine.

Generally, while driving on the road, we encounter road congestion due to an accident with another vehicle or waiting at a traffic light, and are forced to stop for a long time (in this case, we stop the engine and restart the engine when the congestion clears). Perform operations.

This is to avoid wasteful fuel consumption due to long periods of idling.

On the other hand, if the engine is stopped when the vehicle is stopped at a traffic light at an intersection in the city, the engine must be restarted each time the vehicle starts, which is not only troublesome but also lacks the speed of starting.

However, stoppage time during city driving occupies a considerable proportion of the total operating time, and the amount of exhaust gas emitted and fuel consumed due to idling cannot be ignored.

Therefore, an automatic engine stop/start device automatically stops the engine under certain conditions, such as when the car stops at an intersection etc. while driving in the city, and automatically starts the engine when a normal start operation (depressing the clutch pedal) is performed. is being developed.

Conventional devices of this type do not take any measures to prevent the rotation of the engine crankshaft from being sufficiently transmitted to the alternator due to factors such as loosening of the fan belt, resulting in a decline in battery charging performance. It had not been taught. Therefore, if the function of automatically stopping or starting the engine is activated to repeatedly stop and start the engine under such conditions, there is a drawback that it becomes impossible to restart the engine.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic engine stop/start control method that prevents the engine from being unable to restart due to battery charging failure.

A feature of the present invention is that the detection outputs of each package sensor or circuit section that detect the operating state of each part of the vehicle are taken in, and the engine is automatically stopped or started under predetermined conditions based on these detection outputs. Then, the slip rate of the alternator is calculated from the frequency of the neutral point output of the alternator, the number of engine revolutions, and the googly ratio, and the slip rate is the set value necessary to maintain the alternator's battery charging state. The feature is that the configuration is configured to cancel the setting of a warning and/or a function to automatically stop or start the engine if the limit is exceeded.

Embodiments of the present invention will be specifically described below based on the drawings. FIG. 1 shows the overall configuration of an automatic engine stop/start device to which the present invention is applied. In the figure, 1 is a control circuit, and detection outputs from various sensors are input to the control circuit 1. Ru. Reference numeral 10 is a main switch for setting or canceling a function to automatically stop or start the engine (hereinafter referred to as E RS). is set. Further, after setting the EFLS, if the main switch 10 is pressed again, the EILS is canceled. The setting of EH8 is automatically canceled under other predetermined conditions, which will be described later.

Reference numeral 12 in the length is a vehicle speed sensor, which detects whether the vehicle is running or stopped, and the detection output of the sensor 12 is used to determine whether the engine should automatically stop. It will be done. Reference numeral 14 denotes an ignition circuit 1, and the ignition pulse signal 15 outputted from the ignition circuit 14 is processed by the control circuit 1 as an engine rotation speed signal. As will be described later, this engine rotational speed signal is used to determine conditions for setting EH8, automatic engine stop F, automatic engine start, and cancellation of EH and S settings. 16 is a clutch pedal,
18'A118B are a clutch upper switch and a clutch lower switch which are turned on and off by movement of the clutch pedal 16, respectively. Each of these switches detects the amount of depression of the clutch pedal 16.
The clutch upper switch 18A is turned on when the clutch pedal 16 is depressed by a certain percentage of the full stroke (for example, 30% or more), sends the signal No. 1g to the control circuit 1, and the control circuit 1 controls the engine so as not to stop.

Also, the clutch lower switch 18B is the clutch pedal 16
When the switch is fully depressed, the switch turns on and sends a signal (a signal that permits automatic engine start) to the control circuit Ml.

The engine 20 is also provided with a water temperature switch 22 that detects the engine cooling water temperature and an oil pressure switch 24 that detects the oil pressure of the engine oil, and these detection outputs are input to the control circuit 1. 26 is a charge rung switch for displaying the power generation state of the alternator, and the switch 26 is turned off when the alternator is generating power. 28 is a battery voltage input, and 30 is a magnet switch that controls the operation of the cooler compressor in the near conditioner, and is turned on when the cooler compressor is operated.

Further, 32 is a headlamp switch 34 that switches the headlamp on and off, and a wiper switch that switches the wiper between operating and non-operating states, and sends a signal from the LO terminal to the control circuit 1.These switches 30.32
．． Reference numeral 34 is for detecting whether or not an electrical load with large current consumption is in an operating state. Further, 36 is a turn signal switch of the vehicle, which outputs a right turn signal of the vehicle. 38 is a door switch that detects the opening/closing state of the driver's side door. Of these detection methods, the former is used to determine the automatic engine stop condition, and the latter is used to determine the EH8 setting condition and setting cancellation condition. . 50 is a slope switch that is turned ON when the gradient of the slope on which the vehicle is stopped is equal to or higher than a predetermined value; 52 is an idle switch that detects whether the engine is in an idling state (turned ON in an idling state); This is an after-default switch that detects whether or not the default switch is being used.

Further, 80 is a display device, and the display device 80 is a control circuit 1 which includes an alternator middle output point output 110 outputted from the alternator 100, an ignition/curse signal 15, and a control circuit 1.
O based on the boolean ratio stored in advance in the internal memory.
When the slip rate of the alternator pulley calculated by IL exceeds the set value () (value necessary to maintain the soteri photoelectric state), a warning and display are issued based on the control signal 90 output from the control circuit 1. .

Here, the slip rate of the alternator is 5117 7
If the rotation speed is NE1, the rotation speed of the alternator is NG, and the actual rotation speed of the alternator is N.
G', pulley ratio is k, slip ratio S and alternator 14KNG, Nj is the following formula % formula % (2) (3) Also, the ripple of alternator neutral point output 110 Here, the alternator is 3-phase. , whose output is assumed to be full-wave rectified.

Therefore, since P- is a constant, if the engine rotational speed N and ripple frequency f are known, the slip ratio S can be determined from equations (1), (2), and (4).

Incidentally, the set value SO to be compared with the slip ratio S calculated from the above equation is selected to be a value that is slightly more leeway than the limit value that can maintain the battery state of charge.

Also, the number of poles P for a 7°-reflection ratio is, for example, k = 1.7 to 2
．． 5, P-12.

Now, after the predetermined conditions are satisfied and E It S is set by the main switch 10, the engine 20 is automatically stopped F.
, automatic starting is performed as follows. That is, when the stop condition for the engine 20 is satisfied, the engine stop signal 44 is output from the GL circuit to the fuel cut relay 40, and as a result, the fuel cut relay 40 controls the fuel cut solenoid (not shown) of the fuel supply system in the engine 20. Then, a fuel cut signal 50 and an ignition cut signal 60 are output to the ignition circuit 14, and the engine is stopped. However, in order to achieve the engine automatic stop function, it may be configured to only cut the ignition without cutting the fuel, but in this case, the engine runs on, so the driving feeling It has the disadvantage that it worsens.

-10,000El (S is in the setting state and when the clutch pedal 16 is fully depressed while the engine is stopped, the clutch lower switch 18B is turned on, and when other conditions are satisfied (described later)) control Starter relay 41 from circuit 1
Engine start No. 14 46 is output, and as a result, the starter 42 is energized and the engine 20 is started.

In addition, after the engine is started, if the slip ratio of the alternator pulley S'b''-8≧SO, the control amount w51 sends an open side J signal 90 to the display device 80 to notify that the battery charging state is poor. At the same time as outputting, the EFtS setting is automatically canceled.

Next, E)1 of the engine automatic stop/start device shown in Fig. 1.
Each operation mode of engine stop and engine start after S setting, E-S setting will be explained based on FIGS. 2 to 4. Fig. 2 shows the operation mode of the E RS v foot, and as shown in the figure, the E RS can be set when the following six conditions are met. settings have been canceled.

(2) The main switch for setting E-S is in the ON state.

(3) When the engine is rotating (for example, the engine speed is 400 to 50 rpm or more).

(4) The alternator is generating power.

(5) The driver's side door is closed (detected by the door switch).

(6) The slip rate of the alternator must be less than the set value (S≦So).

Here, the cancellation of the E RS setting (1) may be performed manually by suppressing the main switch or automatically, and this will be described later.

Also, to detect whether the engine is rotating or not (3
) and the power generation state of the alternator in (4).This is to accurately detect whether the engine is in a rotating state.Furthermore, condition (6) is satisfied. If not, IH1 via inverter 110]
An abnormality is displayed on the display device 80 by the control signal 90 outputted from the controller INrl.

Next, FIG. 3 shows the operation mode of automatic engine stop by ER8. As shown in the figure, when the following conditions (1) to (13) are ANDed, the engine is automatically stopped.

(1) E It S is set.

(2) When the engine speed is at a specified speed (e.g. 85
0 rpm) or less.

(3) Clutch upper and lower switch 18A118
B are both in the OFF state, that is, the clutch pedal 16 is not depressed.

(4) Turn signal switch 36 is in OFF state fi
, that is, the right turn signal is not output.

(5) The headlamp switch 32 is in the OFF state.

(6) The wiper switch 34 is in the OFF state.

(7) The water temperature switch 22 is in the OFF state, that is, the engine cooling water temperature is within a specific temperature range (for example, 75°C to 105°C).

(8) The air conditioner magnet switch 30 is in the OFF state.

(9) A predetermined time (for example, 4 seconds) has elapsed after the engine was started by ER8K.

(10) The vehicle must be in a stopped state.

(11) The slog switch 50 is in the OFF state.

(12) The idle switch 52 is in the OFF state.

(13) The defogger switch 54 is in the OFF state.

(11) Of the above conditions, (2), which requires the engine speed to be 850 rpm or less, is intended to prevent automatic engine stop during racing. In addition, (4) was selected as the judgment condition because the driver sometimes needs to pay attention to checking for oncoming vehicles when the vehicle is on the right side, and it is not desirable to stop and reduce the engine in such conditions. There is.Furthermore, condition (5), (
6), (8), and (I3) are used to determine engine stoppage in order to prevent the battery from being over-discharged by stopping the engine with a high electrical load. (7) makes it difficult for the engine to start when the engine cooling water temperature is low or high, so the engine is not stopped in these temperature ranges.

Regarding condition (9), the automatic engine stop is E RS.
This is because it is performed only after the engine is started.

Furthermore, the condition (01 of 1 - the vehicle is in a stopped state) is determined based on the presence or absence of a change in the level of the detection output (pulse train signal) of the vehicle speed sensor 12.The reason for setting condition (3) is that the vehicle is in a stopped state. This is only possible when the engine (12) is started or when the gear is changed, and this device is configured to start the engine by depressing the clutch pedal.

Furthermore, the reason why both the clutch upper and lower switches 18A and 18B were set to be in the OFF state is that when the clutch upper switch 18A is in the OFF state, the clutch lower switch 18B should also be in the OFF state, so even if both switches are in the normal state, It is sufficient to check only the OFF state of the clutch upper switch 18A, but if the clutch lower switch 18B fails and remains in the ON state, the engine can be turned off automatically by turning the clutch upper switch 18A in the OFF state. Since the engine is stopped and the clutch lower switch 18B is in the ON state (failure), the engine is automatically started. And clutch upper switch 18A
Since the engine is in the OFF state, the engine is further automatically stopped 4, that is, the clutch upper switch 18A is OFF → the engine is automatically stopped - the clutch lower switch 18B is ON → the engine is automatically started - the clutch upper switch 18A is OFF
This is to prevent an abnormal phenomenon (hunting) from occurring in this loop.

Next, FIG. 4 shows an operation mode for automatically starting the engine using the ER8. As shown in the figure, the engine is automatically started when the following conditions (]) to (4) are satisfied: (1) ER5 is set.

(2) The engine rotation speed is set to the set rotation speed (for example, 50 rpm)
) or less.

(3) The alternator is in a state where the vehicle is stopped.

(4) The clutch lower switch is in the ON state, that is, the clutch pedal is fully depressed.

Among the above conditions, (2) and (3) are used to determine whether the engine is in a stopped state, but the reason why both the engine rotation speed signal and the alternator power generation status signal are used for this determination is because both of them are used. This is to enable reliable determination even when one of the signals is not input to the control circuit 1.

In addition, the automatic stop condition is such that the clutch upper switch and lower switches 18A and 18B are both in the OFF' state.
The reason why both B and B are not in the ON state is because the clutch upper switch 18A is in the OFF state.If the engine is automatically stopped once, the engine will not start (that is, the engine automatic start condition is not met). This is to prevent them from becoming unfulfilled.

- After setting E ft S, to cancel it, proceed as follows.

A) When manually canceling EKSO) v constant is canceled by pressing the main switch 10 once after the suppression operation.

B) When automatically released (1) When the ignition switch is manually operated and the engine is restarted.

(2) When the driver's side door is opened.

(3) When the battery voltage drops.

(4) 8 When starting, it takes more than a certain time ((15) for example, 2 seconds) for the engine N rotation speed to reach a certain rotation speed (for example, 550 rpm) or more.

(5) When the slip rate of the alternator exceeds the set value (S>So).

In the above cases, the ER8 setting is automatically canceled. Among the above conditions, (1) is because the driver may forget that the engine has automatically stopped due to ER8 and restart it with the key switch out of habit, and (2) is due to the fact that the ER8 This is to avoid confusion for people who are unfamiliar with it.

In addition, (3L (4) is ノ (E with the engine lid lowered). If the tS is activated, it will be difficult to restart.
Start with ER8 only that time, and ER8 at the same time as starting.
I am trying to cancel the setting. Furthermore, (5) takes into account the fact that the engine cannot be restarted due to a decrease in the photoelectric state of the battery.

As explained above, in the invention, the slip rate of the alternator pulley is calculated from the frequency of the neutral point output of the alternator, the engine speed, and the pulley ratio, and the slip rate is determined to be necessary to maintain the alternator battery in a full state. Since the configuration is configured such that (16) the warning and/or the function that automatically stops or starts the engine is canceled when the set value is exceeded, so according to the present invention, the engine cannot be restarted due to insufficient charging of the battery. This can be prevented.

[Brief explanation of drawings]

Fig. 8111 is a block diagram showing the overall configuration of an automatic engine stop/start device to which the present invention is applied, Figs. 2 to 4 show operation modes in control law [1], and Fig. 2
FIG. 3 is an explanatory diagram showing the operating mode at the time of setting, FIG. 3 is the operating mode when the engine is automatically stopped, and FIG. 4 is an explanatory diagram showing the operating mode when the engine is automatically started. 1...Control circuit, 10...Main switch, 12...
・Vehicle speed sensor, 14...Ignition circuit, 18A・18B・
...Clutch switch, 20...Engine, 26...
- Selector switch, 28...Battery voltage, 80 Kama indicator, 100...Alternator. Agent Tatsuyuki Ue (and 2 others)

Claims (1)

[Claims] (1) In a device that captures the detection output of each extraction sensor or circuit section that detects the operating state of each part of the vehicle, and automatically stops or starts the engine under predetermined conditions based on these detection outputs, the alternator The slip rate of the alternator is calculated from the neutral point output frequency, engine speed, and Guley ratio, and if the slip rate exceeds the set value necessary to maintain the alternator battery charging state, a warning is issued. /or A method for automatically stopping and starting an engine, which includes canceling the setting of a function that automatically stops or starts the engine.