JPS5818538A - Automatically starting and stopping method of automobile engine - Google Patents

Abstract

PURPOSE:To surely perform an automatic start of an engine, by automatically starting the engine with a starter while automatically flowing an electric conduction current in a starter circuit with the lapse of a prescribed time immediately after a cut of electric conduction to the starter circuit at failure of starting. CONSTITUTION:If a movable contact 13a of an ignition switch 13 is successively connected to fixed terminals 13b, 13c, an engine is started by a starter 11, and high voltage is generated by a regulator relay 15 under control of an alternator 14. If a start of the engine is detected, a starter relay 32 is deexcited to stop the starter 11, when the start is failed, the starter 11 is operated again with the lapse of a prescribed time. Then an automobile is driven, if stopped by waiting of a signal and/or a jam, a normally closed contact 34b of an ignition relay 34 is opened by a microcomputer 20 in accordance with outputs from a speed sensor 16, clutch switches 18a, 18b, etc., and the engine is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for automatically starting and stopping an automobile engine, and in particular, automatically starts the engine when the automobile starts, and after the automobile starts, the automobile is in a running state. The present invention relates to a method for automatically starting and stopping an automobile engine, which maintains the rotation of the engine based on the above and stops the engine when the automobile stops.

Conventionally, in this type of automatic start/stop method, when starting a car engine, the starter of the engine is automatically energized and driven in response to depression of the car's clutch pedal, and the engine starts its rotation. The speed increases as the rotational speed of the starter increases, and when the starting is completed, this is detected and the energization to the starter is cut off to stop the starter.

By the way, if the engine suddenly stops for some reason immediately after the engine has been started, the rotational speed of the engine will drop rapidly, but the rotational speed of the starter will only drop slowly. Therefore, if the starter is automatically reenergized and driven by depressing the clutch pedal in such a state, the rotational speed of the starter will be
Starting from the decreasing value, it begins to increase. For this reason, there is a significant difference in the surface rotational speeds of the starter and engine when the starter is reenergized, and as a result, the pinion provided on the output shaft of the starter meshes smoothly with the ring gear provided on the engine's 7-line wheel. However, there is a problem in that noise such as gear noise or damage such as abrasion may be caused to the connecting portion between the starter and the engine, such as a pinion or ring gear.

The present invention has been made in order to solve this problem, and its purpose is to provide a power supply to the starter circuit when the engine suddenly stops immediately after the power supply line to the starter circuit is disconnected when starting the engine of the automobile. An object of the present invention is to provide a method for automatically starting and stopping an automobile engine, in which a starter circuit is automatically energized under the operation of a starting operation mechanism of the automobile when a predetermined time has elapsed after the energization is cut off.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, numerals 11 and 12 respectively indicate a starter and an ignition circuit of an automobile engine (fueled by gasoline), and the starter 11 is an ignition switch. It is connected to the DC power supply 10 via 13. When the ignition switch 16 is operated to temporarily connect the movable contact 1 loa to the fixed terminal 13C, the starter 11 is supplied with power from the DC power source 10 and starts, putting the engine in a cranking state. The ignition circuit 12 is a control circuit 12a connected to a signal generator provided in the distributor of the engine.
and an ignition coil 12C connected to the control surface path 12a via a transistor 12b. Transistor 12b becomes conductive under the control of control circuit 12a in response to generation of a signal from the signal generator and becomes non-conductive in response to disappearance of the signal from the signal generator. The ignition coil 12C is enabled to receive power from the DC power source 10 and is energized in response to the conduction of the transistor 12b, and is cut off from the energized state in response to the non-conduction of the transistor 12b to generate a spark voltage and apply it to the distributor. .

The alternator 14 is connected between the DC power supply 10 and the regulator relay 15, and when driven by the engine, it generates an AC voltage at the neutral point N of its stator coil, exchanges it with DC voltage, and converts it into a DC voltage. power supply 10
supply to. The regulator relay 15 includes an electromagnetic coil 15a connected between the neutral point N of the stator coil of the alternator 14 and a ground terminal 15C, and a double-headed contact connected to a ground terminal 15C or a left-end terminal 15d connected to the DC power supply 10. 15b. However, electromagnetic coil 1
When 5a is in the demagnetized state, double-headed contact 15b is connected to ground terminal 15C and generates a low voltage L0 from the output terminal. When the electromagnetic coil 15a is excited by the alternating current voltage generated at the neutral point N of the stator coil, the double-headed contact 15b is connected to the fixed terminal 15d and the high voltage H5 is applied from the output terminal.
occurs.

The microcomputer 20 has a regulator relay 15
, speed sensor 16, set switch 17, first clutch switch 18a1, second clutch switch 18b and door switch 19. The speed sensor 16 is composed of a disc 16a made of a permanent magnet and a reed switch 16b arranged to form a magnetic relationship with each protrusion of the disc 16a. It is attached to a speedometer drive cable 16C connected to the output shaft of the power transmission device.

When the disk 16a rotates in conjunction with the drive cable 16C, the reed switch 16b sequentially detects each protrusion on the disk 16a and generates a series of speed pulses corresponding to the actual speed of the vehicle.

The set switch 17 is a normally open switch with a self-reset function, and is provided at a suitable location in the vehicle interior of the vehicle. Thus, the set switch 17 generates a set signal by temporarily closing it. The first and second clutch switches 18a and 18b are both provided on the clutch pedal of the vehicle, and the first clutch switch 18a is of a normally open type, so that when the clutch pedal is fully depressed, the first clutch switch 18a is of a normally open type. Generate a signal. The second clutch switch 18b is of a normally closed type, and generates a second clutch signal when the clutch pedal is depressed, and disappears when the clutch pedal is released. The door switch 19 is a normally closed type switch, which is installed on the door of the vehicle, generates a door signal when the door is opened, and extinguishes this door signal when the door is closed.

The microcomputer 20 is formed of an LSI, and becomes activated in response to a constant voltage (5V) generated from a constant voltage circuit 21 by power supply from the DC power supply 10 when the ignition switch 16 is closed. The microcomputer 20 includes a central processing unit (hereinafter referred to as CPU), an input/output device (hereinafter referred to as 110), a read-only memory (hereinafter referred to as ROM), a random access memory (hereinafter referred to as RAM), and A clock circuit is provided for these CPUs, /r3
M, RAM, and clock circuits are connected to each other via bus lines. ■10 is the low voltage from regulator relay 15. (or high voltage H1), each speed pulse from the speed sensor 16, the set signal from the set switch 17, the first and second clutch switch 18a
, 18b and a door signal from the door switch 19 and apply them to the RAM. The clock circuit is connected to a crystal oscillator 22 and cooperates with the crystal oscillator 22 to generate a series of clock signals. ROM K stores in advance a main control program and an interrupt control program necessary for the CPU to execute the flowcharts shown in FIGS. 2 and 6, respectively.

The cPU has an interrupt timer, which starts timing at the same time as the interrupt timer microcomputer is started, and when the clock value reaches 1m Set, it is reset and starts counting again. Thus, the CPU executes the main control program in response to a series of clock signals from the tarock circuit, and each time the interrupt timer reaches 1m set, the CPU stops executing the main control program and interrupts. The control program is executed, and by alternately executing both control programs, various calculation processes are performed as described below, and the drive signal (or drive stop signal) and drive signal necessary to drive (or stop) the starter 11 are generated. Ignition coil 1? generates the energization signal (or energization stop signal) necessary for energization (or de-energization) of the In this case, the execution of the main control program by the CPU is repeatedly completed within 10 m5 IC after its start.

In the microcomputer 20, a starter relay 32 and an ignition relay 64 each have a transistor 3.
1 and 36. transistor 31
On that basis, ■10 of microcomputer 20
It is connected to the fixed terminal 16b of the ignition switch 16 at its emitter, and conducts when it receives a drive signal from the CPU when the ignition switch 13 is closed, and when it receives a drive stop signal from the CPU. It becomes non-conductive. Transistor 66 is connected to ground at its emitter and to 110 at its base, and is connected to C
It becomes non-conductive upon receiving the energization signal from the PU, and becomes conductive upon receiving the energization stop signal from the CPU.

The starter relay 32 has an electromagnetic filter 32a and a normally open contact 32.
The electromagnetic coil 32a is grounded at one end and connected to the flap of the transistor 61 at the other end, and is excited by receiving power from the DC power supply 10 while the transistor 61 is conducting. Demagnetized in response to non-conduction. Normally open contact 321 of starter relay 32
t- connected between the DC power supply 10 and the starter 11, and the electromagnetic coil 3? closes in response to excitation of the DC power supply 10
The starter 11 is started by allowing power to be supplied from the starter 11 to the starter 11. Further, the normally open contact 32b opens to cut off the power supply to the starter 11 and stop it in response to demagnetization of the electromagnetic coil 32a. The ignition relay 34 consists of an electromagnetic coil 34a and a normally closed contact 34h.
is connected between the fixed terminal 13b of the ignition switch 13 and the collector of the transistor 63.
It is placed in a demagnetized state when the transistor 6 is non-conducting, and is magnetized by receiving power from the DC power supply 10 in response to the conduction of the transistor 33. The normally closed contact 34b closes when the electromagnetic coil 34a is in a demagnetized state to allow power to be supplied from the DC power supply 10 to the ignition coil 12c, and opens in response to excitation of the electromagnetic filter 34a to close the ignition coil 1.
Cut off the power supply to 2C.

In this embodiment configured as described above, when the ignition switch 16 is operated to connect the movable contact 13a to the fixed terminal 11 while the vehicle is stopped, the constant voltage circuit 21 is connected to the DC power source. 10 generates a constant voltage, and in response to this, the microcomputer 20 becomes operational. At the same time, the OPH interrupt timer starts executing the controller control program at step 4o. Next, when the ignition switch 16 is operated to temporarily connect the movable contact 13a to the fixed terminal 16c, the starter 11 receives power from the DC power supply 10 and starts the engine in cooperation with the ignition circuit 12. . At this time, regulator relay 15 generates high voltage H7 under the control of alternator 140.

It is assumed that the reed switch 16b is closed due to a magnetic relationship with the disc 16a when the vehicle is stopped.

When the main control program proceeds to step 41 in this state, the cPU initializes the contents of the microcomputer 20, resets the flag F, and sets the flag F1 to the actual level (currently) of the speed pulse from the speed sensor 16. In this step, since the reed switch 16b is closed, the speed pulse to be generated from the reed switch 16b is assumed to be at a low level, that is, 0.)
The main control program advances to step 42, where it is determined whether flag F is in the reset state. in this case,
Flag F indicates that a set condition for setting the engine under automatic start/stop control is met, and this set condition means that regulator relay 15 is set to high voltage ■
1, the door signal from the door switch 19 has disappeared, and the set switch 17 is generating a set signal.

In this state, if the CPU stops executing the main control program in response to the clock value from the interrupt timer and starts executing the interrupt control program in step 60 (see FIG. 3), The speed pulse from the speed sensor 16 (currently a low level signal) is sent to the next step 61.
is stored in RAM. The interrupt control program proceeds to step 62, where the CPU determines whether the memory cell at step 61 is at a high level. Then, the CPU determines "NO" and advances the interrupt control program to step 63, where it is determined whether the flag F1 is set to a low level, that is, 0.

Then, the CPU selects "YE8 J" based on the set level of flag F1 in step 41 of the main control program.
In the next step 68, 11'' is added to the counted value C by the RAM counter, and this addition result is newly calculated as C.
The interrupt control program advances to step 69, and it is determined whether or not the count value C is north of 2 set.
. In this case, the RAM counter counts the time during which the level of the speed pulse stored in the RAM does not change in response to the clock signal from the clock circuit, and the addition value "1" by the RAMQ counter is calculated by the execution of the interrupt control program. It corresponds to the time required for (1 m set ). However, since the count value C has not yet reached 2 seconds or more, CP
In step 69, U determines l'''noJ, and in step 71, the execution of the interrupt control program is ended.

When the execution of the interrupt control program is finished and the main control program is executed, the CPU executes step 4.
2, based on the reset state of the flag F5 in step 41, it is determined that l'-vEsJ, and the main control program proceeds to step 43, where it is determined whether or not the set condition is satisfied. At present, at least the set switch 17
is not being operated, the CPU executes l in step 46.
'noJ', the main control program advances to step 50, and it is determined whether or not the starter 11 is being driven.

Then, since the CPTJ has not yet generated a drive signal, the determination is "NO", and the main control program is executed at step 42.
Return to Note that during the execution of the main control program described above, the CPU sets the time value of the interrupt timer to 1m set.
Each time, the execution of the main control program is stopped and the interrupt control program as described above is executed.

While each of these control programs is being executed, the door switch 19 responds to the closing of the door of the vehicle by extinguishing the door signal, and the set switch 17 generates a set signal by its temporary operation. When the main control program reaches step 43, the CPU generates the high voltage H7 from the regulator relay 15 and the set signal from the set switch 17, and generates the door switch 19.
Based on the disappearance of the door signal from [YE8 J,
The main control program is further advanced to set a flag F in step 44, and in the next step 45 it is determined whether or not the engine is stopped. Then, based on the high voltage H from the CPU regulator relay 15, the
Then, in step 55, it is determined whether the engine stop condition is satisfied. In this case, the second clutch switch 18
The second clutch signal from b has disappeared and RA
This is established due to the simultaneous establishment of two requirements that the counted value C by the counter of M is 2 Se (the time required for the vehicle to stop once after the operation of the brake pedal).

However, assuming that the count value C from the RAM counter is not greater than 2 sets at this stage,
The CPU makes a 1NO determination in step 55 and returns the main control program to step 42.

As described above, when the main control program returns to step 42, the CPU determines "No" based on the result of setting flag F in step 44, and sets the cancellation condition for canceling the engine from under automatic start/stop control. The main control program advances to step 54 in which it is determined whether or not this is true. In this case, the cancellation condition is satisfied when the requirement that a door signal is generated from the door switch 19 or a set signal is generated from the set switch 17 while the flag F is set is satisfied. Therefore, since the door signal from the door switch 19 has disappeared and the set signal has not been generated from the set switch 17, C
! The PU makes a 1NO determination in step 54 and returns the main control program to step 42 through steps 45 and 55.

In such a state, when the vehicle starts by operating its starting operation mechanism, the traveling speed of the vehicle is detected as a speed pulse by the speed sensor 16 and sent to the microcomputer 20. At this stage, CPU
stops the execution of the main control program in response to the time value from the interrupt timer and starts execution of the interrupt control program in step 60 (see FIG. 3), the 7 degree pulse from the speed sensor 16 is stored in RAM K in the next step 61. Therefore, the interrupt control program executes step 62.
If the speed pulse is passed, the CPU determines whether or not the speed pulse stored in step 61 is at a high level.

If the speed pulse stored in step 61 is at level 71, the CPU advances the interrupt control program to step 64 and determines whether the flag F is at level 71 or not. Therefore, based on the level of 7 lag Fl in step 41 of the main control program, the CPU
NO", the interrupt control program proceeds to step 66, and the flag F knee 1 is set. When the interrupt control program proceeds to step 67, the CPU resets the count value C of the counter provided in the RAM, and the interrupt control program ends at step 71. After the execution of the interrupt control program is finished, the main control program proceeds to step 55;
CPIJ determines "NO" in relation to the reset result in step 67 of the interrupt control program, and returns the main control program to step 42.

Thereafter, when the execution of the main control program is shifted to the execution of the interrupt control program in the same way as in the case described above, the speed pulse from the speed sensor 16 is stored in the RAM in step 61.
is memorized. - However, if the speed pulse stored in this RAM is at a low level, that is, 0, the CPU makes a 1'lJ distinction with "NO" in step 62, and advances the interrupt control program to step 66, setting the methi flag p+=Q. Determine whether it exists or not. Then, the CPU determines l'noJ based on the set result F knee 1 in step 66,
In step 65, F = 0 is set, and in step 67, the count value C of the RAM counter is reset, and the execution of the interrupt control program is ended. Then, when the main control program reaches step 55, the CPU determines "NO" in the same way as in the case described above, and returns the main control program to step 42.

In such a driving state of the vehicle, if the brake pedal is operated to temporarily stop the vehicle at an intersection, etc., the interrupt control program that passes through steps 65 (or 66) and 67 and steps 42, 54, and 45 are executed. and 5
While the qPU repeats each execution of the main control program through step 5, the vehicle is decelerated and stopped in a state where the second clutch signal is generated from the second clutch switch 186 by depressing the clutch pedal, and the second clutch signal is generated from the speed sensor 16. The second clutch signal then disappears upon release of the clutch pedal.

Therefore, the CPU executes step 68 of the interrupt control program.
The addition operation in step 69 and 'NoJ
After repeating the determination as ``NO'' in step 55 of the main control program, when the addition result in step 68 reaches 2 sets or more, the CP
In step 69, U determines [YE8J, and in step 7
At 0, the count value C by the RAM counter is set to 2 set. Then, the main control program executes step 55.
, the CPU determines "YB2 J" based on the disappearance of the second clutch signal from the second clutch switch 18b and the set result in step 70, and advances the main control program to step 56 to generate an energization stop signal. .

Then, the transistor 33 becomes conductive in response to the energization stop signal from the CPU, and the ignition relay 64 is energized by the electromagnetic coil 34a, causing the normally closed contact 34b to stop energizing the open key ignition coil 12c. As a result, the engine stops and regulator relay 15 becomes low voltage. When the main control program that generates ``YB2
Then, the main control program proceeds to step 46 where it is determined whether the starter 11 is stopped. Then, since no drive signal has been generated yet, the CPU determines "YB2 J", and in the next step 47 determines whether or not the engine starting conditions are met.In this case, the engine starting conditions are , regulator relay 1
5 is low voltage. This is achieved by simultaneously satisfying two conditions: that the clutch signal is generated by the first clutch switch 18a, and that the first clutch switch 18a generates the first clutch signal. However, C.P.
Based on the disappearance of the first clutch signal, U determines "NO" in step 47, and returns the main control program to step 42 through step 50.

When the vehicle and engine are temporarily stopped, the clutch pedal is operated to send the first clutch signal to the first clutch switch 18 in order to start the vehicle again.
When generated from a, the main control program executes step 47.
When proceeding to step 41, the CPU determines "YB2 J", and in the next step 48, determines the drive delay time D=Q of the starter 11. The main control program proceeds to step 49a and generates a drive signal.Then, the transistor 31 becomes conductive in response to the drive signal from the OPU, and the starter relay 62 connects the electromagnetic coil 3.
2a closes the normally open contact 32b, and the starter 11
The energization drives the engine to start the engine. At this time, regulator relay 15 generates high voltage H5 under the control of alternator 14 due to engine startup.

When the main control program proceeds to step 50, the CPU
However, based on the drive signal (stored in the input port of Ilo) generated in step 49a, it is determined as "YE8 J," and in the next step 51, it is determined whether or not the stop condition for the starter 11 is satisfied. In this case,
The condition for stopping the starter 11 is established by satisfying the requirement that the regulator relay 15 generates the high voltage 11i. Then, the CPU determines "YB2 J" based on the high voltage H1 from the regulator relay 15 in step 51, advances the main control program to step 52, sets the drive delay time 'D to O, 5SIC, and then A drive stop signal is generated in step 56. As a result, the transistor 31 becomes non-conductive and the normally open contact 52b of the starter relay 62 is opened to cut off the current to the starter 11. Time D = 3
．． 5 sets means the time required for the starter 11 to stop after being de-energized. -By the way, immediately after cutting off the electricity to the starter 11 as described above,
If the engine suddenly stops for some reason, the driver depresses the accelerator pedal to activate the first clutch switch 1.
A first clutch signal is generated from 8a. At this time, the voltage of the regulator relay 15 becomes low due to the sudden drop in engine speed. , and, on the other hand, the rotational speed of starter 1-1 is in a state of gradual decline. When the main control program proceeds to step 47, the CPU determines "YB2 J" and executes the next step 4, as in the case described above.
8, based on the set result in step 52, "NO" is selected.
'', the main control program proceeds to step 49b, 10m5et is subtracted from the result set in step 52, and this subtraction result is newly set as the drive delay time. Thereafter, the main control program passes through step 50 and returns to step 42. Therefore, when the result of this subtraction becomes zero while repeating the determination as "NO" in step 48 and the subtraction in step 49b,
' The CPU determines J YB2 J in step 48, and generates a drive signal in step 49a.

Then, the starter 11 is driven under the control of the transistor 61 and the starter relay 32 in response to a drive signal from the OPU to start the engine.

As can be understood from the above explanation, if the engine suddenly stops immediately after power is cut off to the starter 11 when the engine starts, the driver depresses the clutch pedal to switch the first clutch signal from the first clutch switch 18a. Even if the starter 11 is de-energized, the energization to the starter 11 remains cut off until the drive delay time D −= Q, 5 set elapses after the energization to the starter 11 is cut off, and the drive delay time D=0 When .5set has elapsed, that is, when the rotational speed of the starter 11 becomes approximately zero, the starter 11 is driven by the reenergization and restarts the engine. In other words, drive delay time p = Q, 5
When the difference in rotational speed between the engine and the starter 11 is almost eliminated as a result of the set process, the starter 11 is driven by reenergization, so the pinion provided on the output shaft of the starter 11 is connected to the pinion provided on the flywheel of the engine. The engine meshes smoothly with the ring gear, and as a result, the engine is rotated at its rotational speed while preventing noise such as gear noise and damage such as wear at the connecting portion between the starter 11 and the engine, such as the pinion or ring gear. It rises as the rotational speed of the starter 11 increases and completes its starting. Thereafter, the starter 11 stops in the same manner as in the case described above, and the vehicle starts when the start operation mechanism is operated.

Additionally, when the door of the vehicle is opened while the vehicle and engine are temporarily stopped, the door switch 19
generates a door signal. However, when the main control program proceeds to step 54 in this state, C! P.U.
is determined to be YESj based on the generation of the door signal, and the main control program proceeds to step 57 to reset the flag F. The I, apu generates a drive stop signal in step 58, and generates an energization signal in step 59.

As a result, transistor 61 becomes non-conductive in response to the drive stop signal, maintains the normally open contact 52b of starter relay 32 in an open state, and disables automatic drive of starter 11, and transistor 63 responds to the energization signal. The normally closed contact 34b of the ignition relay 64 is kept closed, and the ignition coil 12C is enabled to be energized. In addition, in a state where the automatic engine start/stop control is canceled in this way, the engine will not start unless the ignition switch 16 is operated.

In the above embodiment, the set value of the drive delay time in step 52 was set to 0.5 seconds, but the present invention is not limited to this, and the drive delay time may be set to 1 set, for example.

Further, in the above embodiment, in determining whether the engine starting condition is met in step 47, the generation of the low voltage Lo from the regulator relay 15 and the generation of the first clutch signal from the first clutch switch 18a are required. I explained the example, but instead of this, Ignition Coil 1? This may be implemented as the determination requirements for the generation of a spark voltage from the first clutch switch 18a, the generation of the first clutch signal from the first clutch switch 18a, and the establishment of the same conditions for the engine.

Further, in the above embodiment, an example in which the present invention is applied to an automobile gasoline engine has been described, but the present invention is not limited to this, and the present invention can also be applied to an automobile diesel engine. In this case, instead of the ignition circuit 12, a fuel injection amount control circuit for controlling the amount of fuel injected into the diesel engine is adopted, and the power of this fuel injection amount control circuit is applied to the normally closed contact 3 of the ignition relay 34.
Fuel injection may be stopped when 4b opens.

Further, in the above embodiment, an example was explained in which the engine is automatically stopped when the vehicle is stopped, but instead of this, for example, a one-touch manual operation switch may be adopted to detect this when the vehicle is stopped. At the same time, the engine may be stopped by manually operating the one-touch manual operation switch.

As explained in detail above, in the method for automatically starting and stopping an automatic military engine according to the present invention, as shown in the above embodiment, the engine starts immediately after the power is cut off to the starter circuit when starting the vehicle. In the event of a sudden stop, the starter circuit is automatically energized under the operation of the starting operation mechanism of the vehicle when a predetermined period of time has elapsed immediately after the energization to the starter circuit has been cut off. The above features make it possible to prevent the problems described at the beginning of this specification from occurring.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIGS. 2 and 6 are flow charts showing the operation of the microcomputer shown in FIG. 1, respectively. Explanation of symbols 11...Starter, 12...Ignition circuit speed sensor, 17...Set switch, 18a...
- First clutch switch, 18b... Second clutch switch, 20... Microcomputer, 31.
33...Transistor, 62...Starter relay, 64...Ignition relay. Applicant Nippondenso Co., Ltd. (and 1 other person) Agent Teru Tani, head patent attorney -

Claims (1)

[Claims] Automatically energizes a starter circuit provided in the engine of the automobile in response to the operation of a starting operation mechanism when starting the automobile, and also energizes an ignition circuit or a fuel injection amount control circuit provided in the engine. cut off,
If the engine stops immediately after the starter circuit is cut off, the starter circuit is automatically reenergized under the operation of the start operation mechanism when a predetermined period of time has elapsed after the starter circuit was cut off. restarting the engine, detecting that the vehicle is in a running state after the vehicle has started, and maintaining energization to the ignition circuit or the fuel injection amount control circuit based on this detection result;
and a method for automatically starting and stopping an automobile engine, wherein when the automobile stops, power to the ignition circuit or the fuel injection amount control circuit is cut off to stop the engine.