JPH11270378A - Restarting control device for engine for vehicle and automatic stopping and restarting control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more smoothly control automatic stopping and restarting of an engine through more natural operation of an occupant. SOLUTION: A vehicle 1 is respectively arranged with a shift selector 32 furnished with a shift position sensor 33, a service brake mechanism 36 furnished with a car speed sensor 34, a brake pedal 40, a master cylinder 41 and a parking brake 37 furnished with a parking brake sensor 9. A service brake hydraulic pressure sensor 42 to detect hydraulic pressure in the master cylinder 41 is arranged in the neighborhood of the master cylinder 41. Additionally, an electric control device (ECU) 50 is arranged on the vehicle 1, and the ECU 50 controls to restart an engine 11 in accordance with a change of hydraulic pressure in the master cylinder 41 after automatically stopping the engine 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle engine restart control device and an automatic stop / restart control device.
More specifically, the present invention relates to a device that automatically stops an engine when a vehicle is stopped and automatically restarts the engine when the vehicle starts to improve fuel efficiency and reduce exhaust gas.

[0002]

2. Description of the Related Art In recent years, in vehicles such as automobiles, reduction of carbon dioxide, improvement of fuel efficiency and reduction of exhaust gas have been demanded due to resource problems and environmental pollution problems due to exhaust gas.

[0003] In response to such demands, there has been proposed a device that automatically stops the engine when the vehicle stops and automatically restarts the engine when the vehicle starts moving. As this type of apparatus, for example, Japanese Patent Application Laid-Open No. 58-383
An automatic stop and start device for an engine described in Japanese Patent Publication No. 46-46 is known. In the device described in the publication, when the vehicle is stopped,
The engine is automatically stopped when the parking brake is actuated by an occupant. And a manual transmission type vehicle (MT vehicle)
In the case of, the engine is restarted when the clutch pedal is depressed, and in the case of an automatic transmission type vehicle (AT vehicle), when the shift position is in the neutral position or the parking position and the accelerator pedal is depressed Controlling to restart the engine.

[0004]

However, in the above-mentioned conventional apparatus, the engine cannot be automatically stopped unless the occupant activates the parking brake, so that the operation is complicated for the occupant. In addition, especially in an AT car, the engine is not restarted unless the shift position is set to a predetermined position and the accelerator pedal is depressed, so that the operation at restart is more complicated. Furthermore, since a slight time difference (time lag) occurs between when the accelerator pedal is depressed and the engine is actually restarted and the vehicle starts, even if the occupant depresses the accelerator pedal to start the vehicle, the vehicle smoothly runs. It has also led to significant deterioration in drivability, such as the inability to obtain a good start.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle engine capable of smoothly controlling the automatic stop and restart of the engine through a more natural operation of an occupant. To provide a restart control device and an automatic stop / restart control device.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, a vehicle engine for controlling restart of a vehicle engine that has been stopped when the vehicle is stopped. The gist of the invention is that the restart control device further comprises control means for restarting the engine based on a change in hydraulic pressure of a service brake mechanism of the stopped vehicle.

According to such a configuration, the engine is restarted more smoothly through a more natural operation of the occupant. In addition, the engine is restarted by the fluid pressure fluctuation of the service brake mechanism, so that when the occupant depresses the accelerator pedal to start the vehicle, the engine is reliably restarted, preventing deterioration of drivability. Is done.

According to a second aspect of the present invention, in the vehicle engine restart control apparatus according to the first aspect, the control means is configured to perform the control based on a fluctuation of a hydraulic pressure of the service brake mechanism at a predetermined level or more. The gist is to restart the engine.

According to such a configuration, the engine does not restart even if a slight change occurs in the hydraulic pressure of the service brake mechanism. Therefore, unnecessary restart of the engine unintended by the occupant is preferably suppressed. .

According to a third aspect of the present invention, in the vehicle engine restart control apparatus according to the first aspect, the control means determines that the hydraulic pressure of the service brake mechanism falls below a predetermined level. The gist is to restart the engine.

According to such a configuration, the engine is restarted when the hydraulic pressure of the service brake mechanism falls below a predetermined level. That is, the occupant can restart the engine by intentionally reducing the hydraulic pressure to a predetermined level or less,
The restart of the engine against the occupant's will is suitably suppressed.

According to a fourth aspect of the present invention, in the vehicle engine automatic stop / restart control device for controlling the automatic stop and restart of the vehicle engine when the vehicle stops, the control is performed in response to the depression operation of the brake pedal. Automatic stop control means for automatically stopping the engine based on the fluctuating hydraulic pressure of the service brake mechanism exceeding a preset first reference hydraulic pressure while the vehicle is stopped, and after stopping the engine, The gist of the invention is to include a restart control means for restarting the engine based on the hydraulic pressure falling below a second reference hydraulic pressure set in advance.

According to such a configuration, the engine is automatically stopped and restarted more smoothly through a more natural operation of the occupant. In addition, the engine is restarted by the fluid pressure fluctuation of the service brake mechanism, so that when the occupant depresses the accelerator pedal to start the vehicle, the engine is reliably restarted, preventing deterioration of drivability. Is done.

According to a fifth aspect of the present invention, in the vehicle engine automatic stop / restart control apparatus according to the fourth aspect, the second reference hydraulic pressure is lower than the first reference hydraulic pressure by a predetermined pressure. The gist is that the hydraulic pressure is set.

According to such a configuration, the engine does not restart even if a slight change occurs in the hydraulic pressure of the service brake mechanism. Therefore, unnecessary restart of the engine that is not intended by the occupant is appropriately suppressed.

According to a sixth aspect of the present invention, in the vehicle engine automatic stop / restart control device according to the fourth or fifth aspect, the automatic stop control means is configured to control the service during the stop of the vehicle. The gist is that the engine is automatically stopped when the hydraulic pressure of the brake mechanism exceeds the first reference hydraulic pressure and the state is maintained for a predetermined time.

According to such a configuration, unnecessary frequent automatic stop and restart control of the engine such as an automatic stop of the engine when the vehicle is stopped for a short time can be suitably suppressed.

According to the seventh aspect of the present invention, the fourth to sixth aspects are provided.
In the automatic stop / restart control device for a vehicle engine according to any one of the above, the restart control means may be configured such that the hydraulic pressure of the service brake mechanism falls below the second reference hydraulic pressure and the creep phenomenon occurs. The gist of the invention is that the engine is restarted when it is in a range exceeding a third reference hydraulic pressure which is at least necessary to keep the vehicle stopped.

According to such a configuration, when the occupant restarts the engine, it is possible to preferably suppress the vehicle from starting to move due to the creep phenomenon. According to an eighth aspect of the present invention, in the vehicle engine automatic stop / restart control apparatus according to the seventh aspect, the restart control means is configured to control a hydraulic pressure of the service brake mechanism to be equal to the second reference hydraulic pressure. And the engine is restarted when maintained for a predetermined time in a range below the third reference hydraulic pressure.

According to this configuration, even if the occupant unexpectedly loosens the pedaling force on the brake pedal and the hydraulic pressure of the service brake mechanism falls momentarily below the second reference hydraulic pressure, the engine is restarted by this. There is no. For this reason, restart of the engine unintended by the occupant is suitably suppressed.

According to the ninth aspect of the present invention, the fourth to eighth aspects are provided.
The automatic stop / restart control device for a vehicle engine according to any one of the preceding claims, wherein a switching operation of at least one of a parking brake and a shift selector is an automatic stop / restart condition, and the automatic stop / restart control of the engine is performed. Control means for performing, and after the engine is automatically stopped by the automatic stop control means, the parking brake,
When the automatic stop condition is satisfied based on at least one switching operation of the shift selector, the prohibition means prohibits the restart control of the engine by the restart control means.

According to such a configuration, even if the engine is automatically stopped due to fluctuations in the hydraulic pressure of the service brake mechanism, if the automatic stop condition is satisfied by subsequently performing a switching operation of the parking brake or the shift selector,
The engine does not restart even if the brake pedal pressure is reduced. For this reason, when the occupant unconsciously loosens the pedaling force on the brake pedal for some reason, restarting the engine against the occupant's will is suitably avoided.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. The vehicle 1 is an automatic transmission type vehicle (AT vehicle). As shown in FIG. 1, the vehicle 1 has an engine 11 mounted thereon. The engine 11 includes a cylinder block 12 and a cylinder head 13. A piston 14 is provided in the cylinder block 12 so as to be able to reciprocate.
4 is a crankshaft 1 via a connecting rod.
5 is connected. A starter 16 that drives the crankshaft 15 when the engine 11 is started is provided at the shaft end of the crankshaft 15. A combustion chamber 17 is provided between the top of the piston 14 and the cylinder head 13. The cylinder block 12 has a water temperature sensor 18 for detecting the temperature (cooling water temperature) THW of the cooling water flowing through the cooling water passage, and a rotation speed sensor 19 for detecting the rotation speed of the engine 11 from the rotation of the crankshaft 15. Is provided.

The cylinder head 13 is provided with an intake port 20 and an exhaust port 21 which communicate with the combustion chamber 17. The intake port 20 and the exhaust port 21 are provided with an intake valve 22 and an exhaust valve 23, respectively. An intake manifold 24 is connected to the intake port 20, and the inside of the intake manifold 24 is an intake passage 24a. Further, a surge tank 25 is provided in the intake manifold 24, and the intake manifold 2 is provided.
A fuel injection valve 26 for supplying fuel to the intake port 20 is provided at an end of the cylinder 4 on the cylinder head 13 side.

A throttle valve 27 is provided in the intake passage 24a. The opening of the throttle valve 27 is adjusted by operating an accelerator pedal (not shown) of the vehicle.
The amount of air sucked into the combustion chamber 17 is adjusted by adjusting the opening of the throttle valve 27. A throttle sensor 28 is provided near the throttle valve 27.

Then, the combustion chamber 1 is connected via the intake passage 24a.
When air is sucked into the fuel injection valve 7, the fuel injection valve 26 injects fuel toward the intake passage 24a to form an air-fuel mixture according to the amount of the sucked air. The air-fuel mixture is drawn into the combustion chamber 17 through the intake port 20 and the intake valve 22.

The cylinder head 13 is provided with a spark plug 29 for igniting the air-fuel mixture that has been drawn.
The ignition coil 29 is electrically connected to an ignition coil 30 and an igniter 31. The igniter 31 is an electronic control unit (hereinafter simply referred to as “ECU”) 5
Current is supplied to and cut off from the primary coil of the ignition coil 30 based on the ignition signal output from the ignition coil 0. The ignition coil 30 is driven by a high voltage induced on the secondary coil when the primary current is cut off. 29 causes a spark discharge. That is, the spark plug 2
9 ignites according to an ignition signal output from the ECU 50 to the igniter 31.

On the other hand, the vehicle 1 is provided with a shift selector 32 for switching a shift position of an automatic transmission mechanism (not shown). A shift position sensor 33 for detecting which range the shift position is in is located near the shift selector 32. The vehicle 1 includes a vehicle 1
A vehicle speed sensor 34 for detecting the speed of the vehicle 1, a battery 35 for supplying electricity to various electric components in the vehicle 1, a service brake mechanism 36 mainly used for decelerating and stopping the traveling vehicle 1, and mainly Parking brakes 37 used when parking are provided. In the vicinity of the parking brake 37, a parking brake sensor 39 for detecting an operation state of the parking brake is provided. The service brake mechanism 36 includes a brake pedal 40 and a master cylinder 41. When the brake pedal 40 is depressed by an occupant, the depression force is converted into a hydraulic pressure in the master cylinder 41, and a braking force according to the hydraulic pressure is generated. It is given to each wheel (not shown) of the vehicle 1. Therefore, the more the occupant depresses the brake pedal 40, the higher the hydraulic pressure in the master cylinder 41 and the greater the braking force. In the vicinity of the master cylinder 41, when the brake pedal 40 is depressed, a service brake hydraulic pressure sensor 42 that detects a hydraulic pressure corresponding to the depression force is disposed.

In the vehicle 1, the water temperature sensor 18, the rotation speed sensor 19, the throttle sensor 28, the shift position sensor 33, the vehicle speed sensor 34, the parking brake sensor 39, and the service brake fluid pressure sensor 4
The starter 16 and the fuel injection valve 26 are electrically connected to the ECU 50 together with the igniter 31. The output voltage of the battery 35 is also monitored by the ECU 50.

Next, the configuration of the ECU 50 will be described with reference to FIG. The ECU 50 stores the ROM (Re
The ROM 51 stores predetermined data, control algorithms, and the like. Also, the ECU 50 executes a calculation process based on various data recorded in the ROM 51 and a control algorithm.
U52 and a RAM (Random) for temporarily storing the calculation results of the CPU 52, data input from each sensor, and the like.
Access Memory) 53. Further, the ECU 5
0 has a backup RAM 54 for storing data to be stored when the engine 11 is stopped.

Then, the CPU 52, the ROM 51, and the RAM
53 and a backup RAM 54 are connected to each other via a bus 55, and the input interface 5
6 and the output interface 57. The input interface 56 monitors the output voltage as described above in addition to the water temperature sensor 18, the rotation speed sensor 19, the throttle sensor 28, the shift position sensor 33, the vehicle speed sensor 34, the parking brake sensor 39, and the service brake fluid pressure sensor 42. Battery 35 is connected. Further, the starter 16, the fuel injection valve 26, and the igniter 31 are connected to the output interface 57. The operation of the starter 16, the fuel injection valve 26, and the igniter 31 is controlled by output signals output based on various control algorithms executed by the CPU 52.

In the present embodiment configured as above, the ECU 50 automatically stops the engine 11 when the vehicle 1 is temporarily stopped due to, for example, waiting for a traffic light, and the vehicle 1 is again stopped. Control for restarting the engine 11 when starting is performed (control for automatically stopping and restarting the engine 11). In the present embodiment, the automatic stop and restart of the engine 11 are controlled in the following manner.

(A) The operation of setting the parking brake 37 to the operating state, or changing the shift position of the shift selector 32 to the drive range ("D", "2", "1", "R").
When the occupant performs an operation of switching from the non-drive range (“N”, “P” range) to the non-drive range (“N”, “P” range), and the predetermined time T1 elapses in that state, the engine 11
To stop automatically. After that, parking brake 3
Operation to release the operating state of the shifter 7 or the shift selector 3
The engine 11 is automatically restarted when an occupant performs an operation of switching the shift position of No. 2 from the non-drive range to the drive range. That is, a control mode in which the engine 11 is automatically stopped and restarted by a switching operation of the parking brake 37 or the shift selector 32.

(B) When the brake pedal 40 of the service brake mechanism 36 is depressed, the depressing force causes the hydraulic pressure PBRK in the master cylinder 41 to exceed a preset first reference hydraulic pressure P1. When the set predetermined time T2 has elapsed, the engine 11 is automatically stopped. Thereafter, the depression force on the brake pedal 40 is reduced, and the hydraulic pressure PBRK decreases between the preset second reference hydraulic pressure P2 and the third reference hydraulic pressure P3. When the time T3 has elapsed, the engine 11 is automatically restarted. That is, a control mode in which the engine 11 is automatically stopped and restarted by the fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36.

(C) The engine 11 is automatically stopped according to the mode (b). Then, the parking brake 37
Operation of the shift selector 32 or the shift selector 32
When the operation of switching the shift position from the driving range to the non-driving range is performed by the occupant, the restart of the engine 11 in the mode (b) is prohibited, and when the operation state of the parking brake 37 is released, Alternatively, the engine 11 is automatically restarted only when the shift position of the shift selector 32 is switched from the non-drive range to the drive range. That is, a control mode in which the engine 11 is automatically stopped by the fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36 and the engine 11 is restarted by the switching operation of the parking brake 37 or the shift selector 32.

Next, the processing operation for automatically stopping and restarting the engine 11 in the control modes (a) to (c) will be described with reference to the flowcharts shown in FIGS. This routine is executed by the RO of the ECU 50.
Based on the control algorithm recorded in M51, CP
It is repeatedly executed, for example, every predetermined time under the control of U52.

First, in step S1, the CPU 52 determines whether or not the vehicle speed SPD is "0" based on the output signal from the vehicle speed sensor 34. Where vehicle speed SPD
If is not "0", it is determined that the vehicle 1 has not stopped, and the process proceeds to step S2. Then, an automatic stop flag XSTOP described later is reset to "0" in step S2, and the count values of the time counters C1, C2, and C3 described later are reset to "0" in subsequent step S3. After completing the processing of steps S2 and S3, the CPU 52 temporarily ends the processing of this routine.

On the other hand, in step S1, the vehicle speed SP
If D is "0", it is determined that the vehicle 1 is stopped, and the process proceeds to step S4. In step S4, the CPU 5
2 is an operation for activating the parking brake 37 or switching the shift selector 32 from the drive range to the non-drive range based on output signals from the parking brake sensor 39 and the shift position sensor 33. Then, it is determined whether or not an “automatic stop condition”, which is conditioned on what has been done, is satisfied. When the “automatic stop condition” is satisfied, the process proceeds to step S5a, and the automatic stop flag XSTOP is set to “1”.
After that, the process proceeds to step S6, where the “automatic stop condition” is set.
Does not hold, the process proceeds to step S5b, sets the automatic stop flag XSTOP to "0", and then directly proceeds to step S6. The automatic stop flag XS
TOP is a flag indicating whether or not the “automatic stop condition” is satisfied.

In step S6, the CPU 52 cancels the operation of the parking brake 37 or shifts the shift selector 32 from the non-drive range to the drive range based on the output signals from the parking brake sensor 39 and the shift position sensor 33. It is determined whether or not a “restart condition” is satisfied, which is based on the condition that the operation for switching to (1) has been performed by the occupant. When the “restart condition” is not satisfied, the process proceeds to step S7.

In step S7, it is determined whether the automatic stop flag XSTOP is "1". If the automatic stop flag XSTOP is "1", it is determined that the "automatic stop condition" is satisfied, and step S is executed.
Move to 8. Then, after adding “1” to the count value of the time counter C1 in step S8, the process proceeds to the subsequent step S9.

In step S9, the time counter C
A predetermined count value CJ1 in which a count value of 1 is set in advance
Is determined. And the time counter C1
If the count value does not exceed the predetermined count value CJ1, the process proceeds to step S10, and if not, the process in this routine is temporarily terminated. That is, the time required for the count value of the time counter C1 to exceed the predetermined count value CJ1 is equal to the time (a).
Corresponds to the predetermined time T1 in the control mode of FIG.

In step S10, an engine automatic stop command is output for other processes such as the ignition timing control process and the fuel injection amount control process performed by the ECU 50, and the engine is automatically stopped. When the processing in step S10 is completed, the processing in this routine is temporarily ended.

On the other hand, when the "restart condition" is satisfied in step S6, the process proceeds to step S11.
The CPU 52 determines in step S11 that the starter 1
6. An engine restart command is output for other processes such as the ignition timing control process and the fuel injection amount control process executed by the CPU 52, and the process in this routine is temporarily terminated. The starter 16, the ignition timing control process, the fuel injection amount control process, and the like restart the engine 11 in response to the engine restart command.

If the automatic stop flag XSTOP is not "1" in the above step S7,
That is, when the “automatic stop condition” is not satisfied, the process proceeds to step S12 (FIG. 4). In other words, after the vehicle 1 has stopped, the process proceeds to step S12 only when the operation of putting the parking brake 37 into the operating state or the operation of switching the shift selector 32 from the drive range to the non-drive range is not performed. .

Then, in step S12, the CPU 5
2 is a hydraulic pressure P in the master cylinder 41 based on an output signal from the service brake hydraulic pressure sensor 42.
It is determined whether BRK exceeds a first reference hydraulic pressure P1 set in advance. That is, here, it is determined whether or not the condition for the automatic stop of the engine 11 in the control mode (b) or (c) is satisfied. And
When the hydraulic pressure PBRK exceeds the first reference hydraulic pressure P1, the process proceeds to step S13, and after adding "1" to the count value of the time counter C2 in step S13, the process proceeds to the subsequent step S14.

In step S14, the CPU 52 determines whether or not the count value of the time counter C2 exceeds a predetermined count value CJ2. If the count value of the time counter C2 exceeds the predetermined count value CJ2, the process proceeds to step S15, where the predetermined count value CJ
If it does not exceed J2, the processing in this routine is temporarily ended. That is, the time required until the count value of the time counter C2 exceeds the predetermined count value CJ2 is the predetermined time T2 in the control mode of (b) or (c).
Is equivalent to

In step S15, as in step S10, the CPU 52 outputs an engine automatic stop command to other processes such as the ignition timing control process and the fuel injection amount control process performed by the CPU 52 to automatically start the engine. Stop. When the processing in step S15 is completed, the processing in this routine is temporarily terminated.

On the other hand, if the hydraulic pressure PBRK of the service brake hydraulic pressure sensor 42 does not exceed the first reference hydraulic pressure P1 in step S12, the process proceeds to step S16. Then, in step S16, the CPU 52 determines that the hydraulic pressure PBRK falls below the second reference hydraulic pressure P2 and
It is determined whether or not the reference hydraulic pressure P3 is exceeded. That is, here, the engine 11 in the control mode (b) is used.
It is determined whether or not the conditions for restarting are satisfied. If the hydraulic pressure PBRK does not satisfy this condition, the processing in this routine is temporarily terminated, and the hydraulic pressure PBRK is terminated.
If this condition is satisfied, the flow shifts to step S17.
In step S17, the CPU 52 sets the time counter C
After adding “1” to the count value of No. 3, the subsequent step S1
Move to 8. Note that the second reference hydraulic pressure P2 is set to a hydraulic pressure that is lower than the first reference hydraulic pressure P1 by a predetermined pressure.
Further, the third reference hydraulic pressure P3 is such that when the engine 11 is started, the vehicle 1 has a creep phenomenon specific to an AT vehicle (the shift position is in the drive range (“D”, “2”, “1”, “R” range)). At some point, even if an idling state occurs and the vehicle moves, the hydraulic pressure is set to a minimum necessary to maintain the vehicle 1 in a stopped state against the creep phenomenon.

Then, in step S18, the CPU 5
No. 2 determines whether or not the count value of the time counter C3 exceeds a preset count value CJ3. As a result, if the count value of the time counter C3 has exceeded the predetermined count value CJ3, the process proceeds to step S19, and if not, the process in this routine is once ended. That is, the time required for the count value of the time counter C3 to exceed the predetermined count value CJ3 corresponds to the predetermined time T3 in the control mode (b).

In step S19, as in step S11, the starter 16, the ignition timing control process, the fuel injection amount control process, and other processes are performed only when the engine 11 is currently stopped automatically. An engine restart command is output to restart the engine 11, and the processing in this routine is temporarily terminated.

Next, the control modes (a) to (c) are as follows.
The following is a general description with reference to FIGS. 5 and 6 in consideration of the control routine described above. (A) Parking brake 37 or shift selector 3
A mode in which the engine 11 is automatically stopped and restarted by the switching operation of 2.

In this control mode, as shown in FIG. 5, when the occupant temporarily stops the vehicle 1 at the time of driving the vehicle 1 due to, for example, waiting for a signal (a1), the parking brake 37 is operated. Is performed, or the operation of switching the shift selector 32 from the drive range to the non-drive range is performed, the "automatic stop condition" is satisfied in the process of step S4, and the automatic stop flag XSTOP is set to "1" by the process of step S5. (A2). When the time (predetermined time T1) elapses until the count value of the time counter C1 becomes greater than the count value CJ1, the engine 11 is automatically stopped by the process of step S10 (a3). Thereafter, when an operation of releasing the parking brake 37 from the operating state or an operation of switching the shift selector 32 from the non-drive range to the drive range is performed as a start preparation operation for starting the vehicle 1 again, the above-described processing is performed in step S6. The "restart condition" is satisfied (a4), and the engine 11 is automatically restarted by the process of step S11 (a
5).

Therefore, according to such a control mode,
The engine 11 can be automatically stopped and restarted by a passenger's intentional operation. Therefore, in particular, the vehicle 1
This is effective when the vehicle is stopped for a long time.

(B) A control mode in which the engine 11 is automatically stopped and restarted by the fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36. In this control mode, as shown in FIG. 5, after the vehicle 1 stops (b1), the switching operation of the parking brake 37 or the shift selector 32 is not performed. Therefore, the "automatic stop condition" is not satisfied in the process of step S4, the automatic stop flag XSTOP remains "0", and the process proceeds to step S12 in the process of step S7. If the occupant depresses the brake pedal 40 when the vehicle 1 stops, and if the hydraulic pressure PBRK in the master cylinder 41 exceeds the first reference hydraulic pressure P1 at the time of the processing of step S12 (b2), step S13 is performed. , S14 are performed.
In this state, if the time (predetermined time T2) elapses until the count value of the time counter C2 exceeds the count value CJ2, the process of step S15 is performed and the engine 11 automatically stops ( b3).
Thereafter, as a start preparation operation for starting the vehicle 1 again, the occupant relaxes the depression force on the brake pedal 40, and when the hydraulic pressure PBRK falls below the first reference hydraulic pressure P1, the process of step S16 is performed. The hydraulic pressure PBRK in the master cylinder 41 is equal to the second reference hydraulic pressure P2 and the third hydraulic pressure PBRK.
When the difference between the reference hydraulic pressure P3 and the reference hydraulic pressure P3 is reached, the processing of steps S17 and S18 is performed (b4). In this state, when a time (predetermined time T3) elapses until the count value of the time counter C3 exceeds the count value CJ3, the process of step S19 is performed, and the engine 11 restarts automatically. (B5).

In this control mode, for example, when the hydraulic pressure PBRK in the master cylinder 41 changes as shown in FIG. 6, the vehicle 1 stops and at time t1, the hydraulic pressure PBRK is reduced to the first reference hydraulic pressure. Exceeds P1. This state is at time t1
, The engine 11 is automatically stopped at the same time t2. The hydraulic pressure PBRK falls below the second reference hydraulic pressure P2 at time t3 when time T3 has elapsed from time t2. Since this state is maintained from time t3 until time t4 after the elapse of the predetermined time T3, the engine 11 restarts at the time t4.

Therefore, according to such a control mode,
The engine 11 is automatically stopped and restarted by the minimum necessary operation performed by the occupant to stop the vehicle 1. Therefore, the occupant does not need to perform a complicated operation such as a switching operation of the parking brake 37 and the shift selector 32 in order to control the automatic stop and restart of the engine 11. Moreover, in this case, the hydraulic pressure PB in the master cylinder 41
When RK falls below the second hydraulic pressure P2, the engine 1
Since the engine 1 is restarted, the engine 11 has already been restarted when the passenger depresses the accelerator pedal to start the vehicle 1. Therefore, the drivability of the vehicle 1 does not deteriorate.

Since the occupant's depression force on the brake pedal 40 varies to some extent, the hydraulic pressure PBRK in the master cylinder 41 also varies as shown in FIG. However, in this control mode of the present embodiment, the hydraulic pressure PBRK falls below a second reference hydraulic pressure P2 which is set lower than the first reference hydraulic pressure P1 which is a condition for automatically stopping the engine 11 by a predetermined pressure. Sometimes, the engine 11 is controlled to restart. Therefore, even if the hydraulic pressure PBRK slightly varies due to the variation in the pedaling force applied to the brake pedal 40, the engine 11 is not restarted. Therefore, restart of the engine 11 unintended by the occupant is appropriately suppressed.

Further, in this control mode, the hydraulic pressure PBRK in the master cylinder 41 is higher than the third reference hydraulic pressure P3, which is the minimum required to hold the vehicle 1 in a stopped state against the creep phenomenon. , The engine 11 is controlled to restart. For this reason, the engine 11
When the vehicle is restarted, the vehicle 1 is prevented from moving due to the creep phenomenon.

(C) A control mode in which the engine 11 is automatically stopped by the fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36, and the engine 11 is restarted by the switching operation of the parking brake 37 or the shift selector 32.

In this control mode, the process of step S15 is performed and the engine 11 is automatically stopped (c1 to c3), similarly to the above (b). After that, when the operation of putting the parking brake 37 into the operating state or the operation of switching the shift selector 32 from the driving range to the non-driving range is performed, the above-described “automatic stop condition” is performed in the process of step S4.
Holds (c4), and the automatic stop flag XSTOP becomes "1" in step S5. For this reason, it is prohibited to move from step S7 to step S12. Therefore, the occupant relaxes the depression force on the brake pedal 40, and the hydraulic pressure PBR in the master cylinder 41 is reduced.
Even if the predetermined time period T3 has elapsed since K is between the second reference hydraulic pressure P2 and the third reference hydraulic pressure P3, the engine 1
1 does not automatically restart. Then, when the operation of releasing the parking brake 37 from the operating state or the operation of switching the shift selector 32 from the non-drive range to the drive range is performed, the "restart condition" is satisfied in the process of step S6 (c5). Then, the engine 11 is automatically restarted by the processing in step S11 (c6).

Therefore, according to such a control mode,
For example, after the occupant automatically stops the engine 11 by depressing the brake pedal 40, and then wants to release the depression of the brake pedal 40 for some reason, the switching operation of the parking brake 37 or the shift selector 32 is performed to perform the switching operation. If the “automatic stop condition” is satisfied, the engine 11 does not restart even if the depression on the pedal 40 is released. For this reason,
The restart of the engine 11 against the occupant's will is preferably avoided.

As described in detail above, according to the present embodiment, the following effects can be obtained. (1) Automatic stop and restart control of the engine 11 can be smoothly performed in response to a more natural operation of the occupant.

(2) Normally, the vehicle 1 in which the occupant is stopped
The operation procedure for starting is to release the depression on the brake pedal 40 and then depress the accelerator pedal.
In the above embodiment, the engine 11 is restarted by the fluctuation of the hydraulic pressure in the master cylinder 41. Therefore, when the occupant depresses the accelerator pedal to start the vehicle 1, the engine 11 has already been restarted. Therefore, the vehicle 1 can be started smoothly, and the drivability of the vehicle 1 can be prevented from deteriorating. In addition, there is a time lag from when the engine 11 restart signal is output until the engine 11 is actually restarted.
BRK is equal to the second reference hydraulic pressure P2 and the third reference hydraulic pressure P3.
Restarting the engine 11 when the vehicle 1 is in between, the engine 11 can be reliably restarted at an earlier timing when the vehicle 1 starts moving, and the drivability is surely deteriorated. Can be prevented.

(3) The second reference hydraulic pressure P2 is equal to the first reference hydraulic pressure P
Since the hydraulic pressure is set to a predetermined pressure lower than 1, the engine 11 does not restart even if the hydraulic pressure PBRK in the master cylinder 41 fluctuates to some extent due to a variation in the pedaling force applied to the brake pedal 40. Therefore, unnecessary restart of the engine 11 that is not intended by the occupant can be suppressed.

(4) After the vehicle 1 stops, the above-mentioned (a) to (a)
Even if the conditions for the automatic stop of the engine 11 in the control mode (c) are satisfied, the engine 11 does not stop automatically unless the conditions are satisfied for a predetermined time. For this reason, unnecessary automatic stop and restart control of the engine 11 such as the automatic stop of the engine 11 when the vehicle 1 stops for a short time can be suitably suppressed.

(5) The engine 1 in the control mode of the above (b)
When the vehicle 1 is restarted, it is possible to preferably suppress the vehicle 1 from starting to move due to the creep phenomenon. (6) The occupant instantaneously relaxes the pedaling force on the brake pedal 40, and the hydraulic pressure PBRK in the master cylinder 41 is reduced to the second
Even if it falls below the reference hydraulic pressure P2, the engine 11
Will not be restarted. For this reason, restart of the engine unintended by the occupant can be suitably suppressed.

(7) Automatic stop and restart control of the engine 11 by switching operation of the parking brake 37 or the shift selector 32, and automatic stop and restart of the engine 11 by fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36 By using the control together, the above three control modes (a) to (c) can be realized. Therefore, the occupant can selectively automatically stop and restart the engine 11 in accordance with the driving situation, thereby improving the controllability.

(8) Even if the brake pedal 40 described above is used
Even if the engine 11 is automatically stopped by depressing the brake pedal, if the "automatic stop condition" is satisfied by subsequently performing the switching operation of the parking brake 37 or the shift selector 32, the engine 11 can be stopped even when the brake pedal 40 is released. Will not restart. Therefore, when the occupant unconsciously loosens the pedaling force on the brake pedal 40 for some reason, it is possible to preferably prevent the engine 11 from restarting against the occupant's will.

The embodiment of the present invention may be modified as follows. -When the engine 11 is in the automatic stop state,
Based on an output signal from the throttle sensor 28, the engine 11 may be restarted when the throttle valve 27 is opened, that is, when the accelerator pedal is depressed by an occupant. In this case, especially in the control mode (a) or (c), the engine 11 can be restarted before the occupant switches the parking brake 37 or the shift selector 32.

In addition to the above, during the automatic stop of the engine 11, the restart control of the engine 11 is performed even when the voltage of the battery 35 falls below a predetermined voltage. By doing so, it is possible to avoid such a disadvantage that the voltage drops to a voltage at which the starter 16 cannot be driven. Incidentally, these two conditions are added to the above embodiment, and 1) the parking brake 37 is released from the operating state.

2) The operation of switching the shift selector 32 from the non-drive range to the drive range is performed. 3) The hydraulic pressure PBRK in the master cylinder 41 is between the second reference hydraulic pressure P2 and the third reference hydraulic pressure P3.

4) The accelerator pedal is depressed. 5) The voltage of the battery 35 decreases. Is a condition for restarting.

The automatic stop and restart control of the engine 11 by the switching operation of the parking brake 37 or the shift selector 32 described above is abolished, and the control is performed only by the fluid pressure fluctuation in the master cylinder 41 of the service brake mechanism 36. It may be.

In the control modes (a) and (c), only one of the switching operations of the parking brake 37 and the shift selector 32 may be controlled.

Based on the output signal from the water temperature sensor 18, when the water temperature is lower than the predetermined temperature, the automatic stop and restart control of the engine 11 may not be performed. With such control, it is possible to avoid such a disadvantage that the engine 11 is stopped during the warm-up operation of the engine 11.

When the engine speed does not satisfy the predetermined speed based on the output signal from the speed sensor 19, the automatic stop and restart control of the engine 11 may not be performed. By doing so, it is possible to prevent the ECU 50 from outputting the restart signal again and driving the starter 16 after the engine 11 is restarted.

In the above embodiment, the automatic stop and restart control of the engine 11 is performed by using an AT vehicle as the vehicle 1, but this may be applied to a manual transmission vehicle. However, in this case, the control by the switching operation of the shift selector 32 described above is abolished.

The occupant may arbitrarily set the values of the predetermined count values CJ1, CJ2, and CJ3 in the control routine. With this configuration, for example, the predetermined count value CJ1 or the count value CJ2 is set to “1”.
, The occupant can automatically stop the engine 11 immediately after the vehicle 1 stops.
Further, for example, if the predetermined count value CJ3 is set to “1”, the time for maintaining the hydraulic pressure PBRK between the second reference hydraulic pressure P2 and the third reference hydraulic pressure P3 can be reduced. That is, even if the occupant releases the depression force on the brake pedal 40 at a stretch, the hydraulic pressure PBRK passes between the second reference hydraulic pressure P2 and the third reference hydraulic pressure P3.
Is restarted. Therefore, it is possible to prevent deterioration of drivability for an occupant who feels it difficult to maintain the hydraulic pressure PBRK between the second reference hydraulic pressure P2 and the third reference hydraulic pressure P3 for a predetermined time.

In the above embodiment, the above (a) to (a)
The control of the automatic stop and restart of the engine 11 is performed in the control mode of (c). In addition to this, the control is performed in the control modes shown as (d1) to (d5) in FIG. You may. That is, as shown in (d1) to (d3), after the engine 11 is automatically stopped in the control mode of (a) (corresponding to (a1) to (a3)), as shown in (d4) and (d5) In the control mode shown in FIG.
Is restarted (corresponding to (b4) and (b5)). By doing so, the occupant can more selectively automatically stop and restart the engine 11 according to the driving situation, and the controllability can be further improved.

When the engine 11 is automatically stopped in any manner, the engine 11 is restarted by the fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36 described above. By doing so, the engine 11 can be restarted by a more natural operation of the occupant, particularly at the time of restart control, and deterioration of drivability can be prevented.

In the above embodiment, when the automatic stop and restart of the engine 11 are controlled by the fluctuation of the hydraulic pressure in the master cylinder 41 of the service brake mechanism 36, the control is based on the first to third reference hydraulic pressures P1 to P3. Although the same control is performed, the engine 11 may be restarted at a preset predetermined level of fluid pressure fluctuation (fluid pressure drop) after the engine 11 is automatically stopped. That is, the engine 11 is restarted by a relative hydraulic pressure fluctuation from the hydraulic pressure PBRK in the master cylinder 41 when the engine 11 is automatically stopped. Even in this case, the engine 11 does not restart even if the hydraulic pressure PBRK slightly changes, so that unnecessary restart of the engine 11 that is not intended by the occupant is appropriately suppressed.

A switch for switching the above-described automatic stop and restart control of the engine 11 between active and inactive may be provided in the driver's seat or the like of the vehicle 1. With this configuration, when the occupant does not need the control, the switch can be switched so as not to perform the control,
The necessity of such automatic stop and restart control of the engine 11 can be determined by the occupant's intention.

In the above embodiment, the automatic stop and restart of the gasoline engine as the engine 11 are assumed to be controlled, but this may be applied to a diesel engine.

While the embodiments have been described above, technical ideas other than the claims that can be grasped from the embodiments will be described below together with their effects. (1) In the vehicle engine automatic stop / restart control device according to any one of claims 4 to 9, when a battery mounted on the vehicle needs to be charged, and when the engine is cold. An automatic stop / restart control device for a vehicle engine, further comprising an automatic stop / restart prohibition unit for prohibiting the automatic stop / restart control of the engine when at least one of the conditions is satisfied.

In this way, it is possible to avoid the inconvenience that the engine is automatically stopped but cannot be restarted, or that the engine is stopped during warm-up operation.

(2) The automatic stop / restart control system for a vehicle engine according to any one of claims 4 to 9 or (1), wherein the automatic stop / restart control for the engine is provided in the cabin of the vehicle. An automatic stop / restart control device for a vehicle engine further comprising switch means for switching between active and inactive.

Thus, when the occupant does not need the control, the control can be prevented from being performed through the switching operation of the switch means.

[0088]

According to the first aspect of the present invention, the engine can be restarted more smoothly through a more natural operation of the occupant. In addition, by restarting the engine due to fluctuations in the hydraulic pressure of the service brake mechanism,
When the occupant depresses the accelerator pedal to start the vehicle, the engine is reliably restarted, so that deterioration of drivability can be prevented.

According to the second aspect of the present invention, the engine does not restart even if a slight change occurs in the hydraulic pressure of the service brake mechanism, and unnecessary restart of the engine unintended by the occupant is preferable. Can be suppressed.

According to the third aspect of the invention, the occupant can restart the engine by intentionally lowering the hydraulic pressure of the service brake mechanism to a predetermined level or less. The restart of the engine against the will can be suitably suppressed.

According to the fourth aspect of the present invention, the engine can be restarted more smoothly through a more natural operation of the occupant. In addition, since the engine is restarted by the fluctuation of the hydraulic pressure of the service brake mechanism, when the occupant depresses the accelerator pedal to start the vehicle, the engine is reliably restarted, preventing deterioration of drivability. can do.

According to the fifth aspect of the present invention, the engine does not restart even if the hydraulic pressure of the service brake mechanism fluctuates to some extent. Therefore, unnecessary restart of the engine that is not intended by the occupant can be suppressed.

According to the invention described in claim 6, unnecessary automatic stop and restart control of the engine such as automatic stop of the engine when the vehicle is stopped for a short time can be suitably suppressed.

According to the invention described in claim 7, when the occupant restarts the engine, it is possible to preferably suppress the vehicle from starting to move due to the creep phenomenon. According to the invention described in claim 8, even if the occupant instantaneously relaxes the depression force on the brake pedal and the hydraulic pressure of the service brake mechanism falls below the second reference hydraulic pressure, the engine is restarted by this. There is no. For this reason, restart of the engine unintended by the occupant can be suitably suppressed.

According to the ninth aspect of the present invention, even if the engine is automatically stopped due to a change in the hydraulic pressure of the service brake mechanism, the switching operation of the parking brake or the shift selector is then performed to satisfy the automatic stop condition. Thus, the engine does not restart even if the pedaling force on the brake pedal is reduced. For this reason, when the occupant unconsciously loosens the depression force on the brake pedal for some reason, it is possible to preferably prevent the engine from restarting against the occupant's will.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view and a block diagram showing a basic configuration of an embodiment of the present invention.

FIG. 2 is an exemplary block diagram showing the electrical configuration of the embodiment.

FIG. 3 is a flowchart showing an automatic stop and restart control procedure of the embodiment.

FIG. 4 is a flowchart showing an automatic stop and restart control procedure of the embodiment.

FIG. 5 is an exemplary flowchart generally showing an automatic stop and restart control mode of the embodiment;

FIG. 6 is a time chart showing an example of an automatic stop and restart control mode of the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vehicle (AT vehicle), 11 ... Engine, 16 ... Starter, 18 ... Water temperature sensor, 19 ... Rotation speed sensor, 26 ... Fuel injection valve, 31 ... Igniter, 32 ... Shift selector,
33: shift position sensor, 34: vehicle speed sensor, 3
5 ... battery, 36 ... service brake mechanism, 37 ... parking brake, 39 ... parking brake sensor,
40: brake pedal, 41: master cylinder, 50
... Electronic control unit (ECU).

Claims (9)

[Claims] 1. A vehicle engine restart control device for controlling a restart of a vehicle engine that has been stopped due to a stop of the vehicle, based on a change in hydraulic pressure of a service brake mechanism of the stopped vehicle. And a control unit for restarting the engine by means of a vehicle. 2. A restart control apparatus for a vehicle engine according to claim 1, wherein said control means restarts said engine based on a fluctuation of a hydraulic pressure of said service brake mechanism at a predetermined level or more. A restart control device for a vehicle engine. 3. A restart control apparatus for a vehicle engine according to claim 1, wherein said control means restarts said engine based on a hydraulic pressure of said service brake mechanism falling below a predetermined level. A restart control device for a vehicle engine, characterized in that: 4. A vehicle engine automatic stop / restart control device for controlling automatic stop / restart of a vehicle engine when the vehicle stops, comprising: a service brake mechanism fluid that varies according to a depression operation of a brake pedal. Automatic stop control means for automatically stopping the engine based on a pressure exceeding a first reference hydraulic pressure set in advance while the vehicle is stopped; and setting the hydraulic pressure in advance after stopping the engine. Automatic restart / restart control device for a vehicle engine, comprising: restart control means for restarting the engine based on falling below a second reference hydraulic pressure. 5. The automatic stop / restart control system for a vehicle engine according to claim 4, wherein the second reference hydraulic pressure is set to a predetermined lower pressure than the first reference hydraulic pressure. Automatic stop / restart control device for vehicle engine. 6. The automatic stop / restart control device for a vehicle engine according to claim 4, wherein the automatic stop control means controls the hydraulic pressure of the service brake mechanism during the stoppage of the vehicle. An automatic stop / restart control device for a vehicle engine, wherein the engine is automatically stopped when the first reference hydraulic pressure is exceeded and the state is maintained for a predetermined time. 7. The automatic stop / restart control device for a vehicle engine according to claim 4, wherein said restart control means controls the hydraulic pressure of said service brake mechanism to be higher than said second pressure. The engine is restarted when the engine pressure falls below a reference hydraulic pressure and exceeds a third reference hydraulic pressure that is at least a minimum required to hold the vehicle stopped against the creep phenomenon. Automatic stop / restart control device for vehicle engine. 8. The automatic stop / restart control device for a vehicle engine according to claim 7, wherein said restart control means comprises:
A vehicle for restarting the engine when the hydraulic pressure of the service brake mechanism is maintained for a predetermined time in a range below the second reference hydraulic pressure and exceeding the third reference hydraulic pressure. Automatic stop / restart control device for the engine. 9. The automatic stop / restart control device for a vehicle engine according to claim 4, wherein at least one of a parking brake and a shift selector is automatically stopped and restarted. Control means for performing automatic stop and restart control of the engine, and after the engine is automatically stopped by the automatic stop control means, the automatic stop condition is determined based on a switching operation of at least one of the parking brake and a shift selector. Prohibiting means for prohibiting the restart control of the engine by the restart control means when the condition is satisfied, further comprising: a vehicle engine automatic stop and restart control device.