JP2016032976A - Vehicular control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular control device which suppresses movement of a vehicle upon engine restart by an idling stop function, while suppressing shock upon stopping by an inter-vehicle distance control function.SOLUTION: In a vehicular control device which comprises inter-vehicle distance control means for controlling the inter-vehicle distance between an own vehicle and a preceding vehicle, engine stop and restart means for stopping the engine of the own vehicle when a specific stop condition is satisfied and restarting the engine when a specific restart condition is satisfied, and braking control means for increasing braking force until becoming more than driving force of the own vehicle upon the restart time when the inter-vehicle distance control means determines stop of the own vehicle, the braking control means increases changing amount per time of the braking force until the braking force becomes more than the driving force after stopping of the own vehicle.SELECTED DRAWING: Figure 6

Description

The present disclosure relates to a vehicle control device.

Conventionally, a technique is known in which an engine is stopped when a predetermined stop condition is satisfied, and the stopped engine is restarted when a predetermined start condition is satisfied. The combination of both is called the idling stop function, start and stop function, engine auto start start stop function, etc. (Hereafter referred to as “idling stop function”).

Also, while capturing the preceding vehicle, adjust the inter-vehicle distance between the preceding vehicle and the host vehicle to follow the preceding vehicle, and the vehicle speed set when the preceding vehicle is not captured. The technology to travel with is known. These technologies are called constant speed traveling / inter-vehicle distance control function, ACC function (Adaptive Cruise Control), etc. (hereinafter referred to as “inter-vehicle distance control function”). As one form of the inter-vehicle distance control function, there is known an all-vehicle speed inter-vehicle distance control function that stops the host vehicle when the preceding vehicle stops and starts the host vehicle when the preceding vehicle starts.

By installing the idling stop function and the full vehicle speed inter-vehicle distance control function in the vehicle, the idling stop function is activated and the engine can be stopped after the host vehicle is stopped by the full vehicle speed inter-vehicle distance control function. (For example, refer to Patent Document 1). In Patent Document 1, a cruise control system that generates a braking force for holding the host vehicle in a stopped state by the all-vehicle speed inter-vehicle distance control function and automatically stops the engine of the host vehicle when an engine automatic stop condition is satisfied. It is disclosed.

JP 2012-206593 A

  By the way, in the vehicle stopped by the full vehicle speed inter-vehicle distance control function, since the shift lever is set to the travel range, the engine speed is transmitted to the tire via the torque converter and the transmission. In such a case, immediately after the engine is restarted by the idling stop function, the engine speed increases so that the number of revolutions is higher than that in the idling state, so that a driving force larger than the braking force for stopping the vehicle may be generated. is there. That is, with the configuration described in Patent Document 1, the driving force may overcome the braking force, and the vehicle may move.

In this state, in order to suppress the movement of the vehicle, it is conceivable to increase the braking force when it is determined that the vehicle has stopped. However, if the amount of change in the braking force per unit time when increasing the braking force is large, the shock at the time of stopping increases, which is not preferable. For example, even if it is determined that the vehicle has stopped based on the wheel speed sensor or the vehicle speed sensor, the vehicle may be moving. On the other hand, if the amount of change of the braking force per unit time when increasing the braking force is small, it takes time to secure a sufficient braking force. For example, there is a possibility that sufficient braking force cannot be secured before the engine is restarted by the idling stop function. That is, it is not preferable because the vehicle may move when the engine is restarted.

Accordingly, the present disclosure aims to provide a vehicle control device that suppresses vehicle movement when the engine is restarted by an idling stop function while suppressing a shock when the host vehicle stops by the inter-vehicle distance control function. To do.

The present invention provides an inter-vehicle distance control means for controlling an inter-vehicle distance between the host vehicle and a preceding vehicle, and stops the engine of the host vehicle when a predetermined stop condition is satisfied, and the engine when a predetermined restart condition is satisfied. Engine stop restarting means for restarting and braking control means for increasing braking force until the driving force of the own vehicle at the time of restarting becomes greater when the inter-vehicle distance control means determines that the own vehicle is stopped. The braking control means increases the amount of change per unit time of the braking force until the braking force becomes larger than the driving force after the host vehicle stops. It is characterized by making it.

ADVANTAGE OF THE INVENTION According to this invention, the vehicle control apparatus which suppresses that a vehicle moves, when an idling stop function restarts an engine, suppressing the shock at the time of stopping by a distance control function between vehicles is obtained.

It is an example of the block diagram of the means and function of the control apparatus for vehicles. It is an example of the flowchart figure explaining the operation | movement procedure of idling stop control when the inter-vehicle distance control function is OFF and the driver is controlling the vehicle speed. It is an example of the block diagram of the distance control function between vehicles among the control apparatuses for vehicles. It is an example of the functional block diagram of the control apparatus for vehicles. It is an example of the map of target acceleration. It is an example of the relationship between the amount of change of the target deceleration, the braking force, the unit time of the braking force, and the elapsed time. It is an example of the flowchart figure explaining the operation | movement procedure of the control apparatus for vehicles.

FIG. 1 is an example of a block diagram of means and functions of the vehicle control device 1 according to the present embodiment. All of these means and functions are not necessarily used for the idling stop function, the stop maintenance function, and the inter-vehicle distance control function, and the arrangement place and shape are merely schematically shown. The ECU and the sensor are communicably connected via an in-vehicle network such as a CAN (Controller Area Network) or a dedicated line.

The battery 15 is a power storage device (secondary battery) that can be charged and discharged. The battery 15 is, for example, a lead storage battery, and supplies power to the electric oil pump 14, a brake hydraulic pump (not shown), the starter 13, and various ECUs (Electronic Control Units). Further, the battery 15 is charged by the electric power generated by the alternator 17. The SOC of the battery 15 is monitored by the battery sensor 16.

The engine 20 includes an electric oil pump 14, a starter 13, an air conditioner compressor 31, an alternator 17, a cam angle sensor 18, and a crank angle sensor 19. The starter 13 consumes the power of the battery 15 and starts the engine 20. When the engine speed is high, the starter 13 can start the engine 20 even while the engine is rotating by rotating the pinion gear and then pushing the pinion gear into mesh with the ring gear. A starter that does not have a function of rotating the pinion gear may be mounted.

The alternator 17 is a generator that generates electricity by rotating in conjunction with the rotation of the crankshaft. The crankshaft and the rotating shaft of the alternator 17 are wound around a belt, and the alternator 17 is rotated by the power of the engine 20. Electric power generated by the alternator 17 is charged in the battery 15.

The compressor 31 of the air conditioner is wound around a crankshaft and a belt, and the compressor 31 is rotated by the power of the engine 20.

The electric oil pump 14 is driven by a battery 15 and circulates engine oil when the engine is stopped to prevent the engine oil from being biased while the engine is stopped, or to cool the engine 20 when the engine is stopped.

The crank angle sensor 19 detects the crank angle, and the cam angle sensor 18 detects the cam angle. Knowing the crank angle and cam angle enables so-called cylinder discrimination. For example, in a four-cylinder engine, the timing at which each cylinder reaches compression top dead center is known, so that it is possible to determine the cylinder to be injected and burned when starting the engine. The crank angle sensor 19 is used for detecting the engine speed.

A hood lock SW 12 and a distance sensor 11 are mounted in front of the vehicle. The hood lock SW12 is a sensor that detects whether or not the engine hood is locked. When the hood is open, the idling stop function prohibits the engine from starting because the driver cannot confirm the front.

The distance sensor 11 is a sensor that detects a distance from an object, such as a millimeter wave radar, a laser radar, a stereo camera, or a TOF (Time of Flight) camera. In addition to distance, relative speed and direction can be obtained. The inter-vehicle distance control function maintains the distance according to the vehicle speed of the host vehicle and causes the host vehicle to follow the preceding vehicle.

The engine ECU 26 is an ECU that controls the engine 20 and is connected to the starter drive relay 21. When the engine ECU 26 energizes the starter drive relay 21, the starter 13 is activated and the engine 20 is started.

The brake ECU 24 controls a brake ACT, which will be described later, to increase, decrease, and hold the wheel cylinder pressure of each wheel. Using this function, the brake ECU 24 performs control for maintaining the stopped state. Also, VSC (Vehicle Stability Control) control, ABS control, TRC control, etc. can be performed. The VSC control controls the wheel cylinder pressure of each wheel so that the host vehicle does not have unstable vehicle behavior such as excessive understeer and oversteer. The brake ECU 24 and the brake ACT can be configured to brake each wheel by supplying the hydraulic pressure accumulated in the pressure accumulator or the like to the wheel cylinder according to the depression force of the driver's brake pedal.

The brake boost negative pressure sensor 23 is a sensor that detects a booster negative pressure formed by using the intake negative pressure of the engine 20. The negative pressure assists the driver's brake pedal force, and the driver can surely step on the brake pedal. The idling stop function prepares for the driver's operation of the brake pedal by starting the engine 20 when the booster negative pressure increases (close to atmospheric pressure) and reducing the booster negative pressure.

The acceleration sensor 22 is a sensor that detects acceleration in the front-rear or left-right direction, and is used to calculate an inclination angle (gradient) of the road surface on which the vehicle has stopped. The braking force for maintaining the state where the vehicle is stopped is corrected according to the gradient.

The air conditioner ECU 27 performs so-called air conditioning control for controlling the room temperature to the temperature set by the driver. When the idling stop function stops the engine, the compressor 31 of the air conditioner stops, so the air conditioner switches to the air blowing function. Note that the idling stop function does not stop the engine 20 while the air conditioner ECU 27 is in the air conditioning control in a state where the difference between the set temperature and the target temperature is large.

The eco-run ECU 28 is an ECU that controls an idling stop function. The eco-run ECU 28 has a function for boosting the battery voltage. When the engine 20 is started by the idling stop function, the eco-run ECU 28 decreases the battery voltage by driving the starter 13, and thus boosts the battery voltage to ensure the necessary voltage of other auxiliary machines (ECU, room lights, etc.). To do.

The eco-run cancel SW 29 is a switch for canceling the idling stop function. When the driver operates the eco-run cancel SW 29 to turn on, the idling stop function is turned off.

The DSS (driver support) _ECU 25 is an ECU that performs inter-vehicle distance control following the preceding vehicle. That is, when a preceding vehicle is detected, the vehicle travels so that the distance from the preceding vehicle becomes the target inter-vehicle distance corresponding to the vehicle speed. When the preceding vehicle is no longer detected, the vehicle travels at a constant speed at the vehicle speed set by the driver. Further, when the preceding vehicle stops, the vehicle stops while maintaining an appropriate inter-vehicle distance, and when the preceding vehicle resumes traveling, the follow-up traveling is started while maintaining the inter-vehicle distance according to the vehicle speed.

The meter panel 30 displays various operation statuses and alarm messages for the inter-vehicle distance control function, the stoppage maintaining function, and the idling stop function, and a warning lamp is lit. An alarm message or an alarm sound may be output not only from the meter panel 30 but also from a speaker.

FIG. 2A is an example of a flowchart showing a schematic operation procedure of the standstill maintenance function alone. In other words, this is an explanation of the operation when neither the inter-vehicle distance control function nor the idling stop function is in operation.

It is assumed that the engine 20 of the vehicle has already been started and the vehicle is running (S1). Next, the driver operates the brake pedal to stop the vehicle (S2).

Next, the brake ECU 24 determines whether or not there has been a stop maintaining function operating operation (S3). The stoppage maintenance function operation operation is, for example, an operation in which the driver depresses the brake pedal with a depression force equal to or greater than a threshold value. In addition, an operation of pressing a predetermined button may be used. The brake ECU 24 detects the value of the master cylinder pressure and the value of the brake pedal stroke, and determines whether or not the vehicle stop maintaining function is operated.

When the stop maintenance function operation operation is detected (Yes in S3), the stop maintenance function is operated (S4). That is, the brake ECU 24 maintains the wheel cylinder pressure using the wheel cylinder pressure obtained by the driver's depression of the brake pedal when the vehicle is stopped. Since the driver can take his foot off the brake pedal while the engine is operating, the degree of freedom of the driver's posture is improved when the vehicle is stopped for a short time.

 When the stop keeping function is activated, the brake ECU 24 determines whether or not the accelerator pedal is operated (ON) (S5). When the accelerator pedal is operated (Yes in S5), the brake ECU 24 releases the wheel cylinder pressure. Therefore, traveling can be resumed promptly.

FIG. 2B is an example of a flowchart showing a schematic operation procedure of the idling stop function alone. That is, it is an explanation of the operation in a state where neither the inter-vehicle distance control function nor the stop keeping function is in operation.

The engine 20 of the vehicle is starting and the vehicle is running (S10). The driver operates the brake pedal to stop the vehicle (S20). Note that stopping the vehicle by the idling stop function generally means that the vehicle speed becomes zero, but there is an idling stop function that stops the engine 20 if the vehicle speed is equal to or higher than zero but below a predetermined value. In this embodiment, for explanation, it is determined that the vehicle has stopped when the vehicle speed becomes zero.

Subsequently, the eco-run ECU 28 determines whether or not to stop the engine 20 based on the engine stop condition (S30). The stop condition varies depending on the vehicle. For example, “the vehicle speed is zero and the brake pedal is depressed”. Other stop conditions include “the air conditioner ECU does not prohibit the engine stop, the SOC of the battery 15 is not lower than the threshold value, the electric load is not higher than the threshold value, the engine water temperature is not lower than the threshold value, and the accelerator pedal is depressed. "Not rare".

When the stop condition is not satisfied or the stop prohibition condition is satisfied (No in S30), the eco-run ECU does not request the engine ECU 26 to stop the engine, and the engine 20 is not stopped.

When the stop condition is satisfied (Yes in S30), the eco-run ECU requests the engine ECU 26 to stop the engine, and the engine ECU 26 stops the fuel injection and stops the engine 20.

When the engine 20 is stopped, the eco-run ECU 28 determines whether to restart the engine 20 based on the restart condition (S40). There are various restart conditions depending on the vehicle. For example, one or more of the following may be mentioned (each condition is an OR condition).
-The brake pedal was turned off from the ON-The accelerator pedal was turned on-The SOC of the battery 15 was below the threshold-The brake boost negative pressure was above the threshold

Note that there is a case where the hood lock SW12 is OFF as a start prohibition condition in which the engine 20 is not restarted even if these restart conditions are satisfied.

The eco-run ECU 28 determines to restart the engine 20 when the restart condition is satisfied and the start prohibition condition is not satisfied. When it is determined that the engine 20 is to be restarted, the eco-run ECU 28 requests the engine ECU 26 to restart, so the engine ECU 26 turns on the tandem starter drive relay 21 to restart the engine 20.

Thus, the engine 20 can be stopped only by the driver stopping the vehicle, fuel consumption in the idling state is reduced, and fuel consumption can be improved.

FIG. 3 is an example of a block diagram of the inter-vehicle distance control function in the vehicle control device 1. The inter-vehicle distance control function is performed by the DSS_ECU 25 cooperating with the distance sensor 11, the engine ECU 26, the brake ECU 24, and the like. Each ECU is an information processing apparatus equipped with a microcomputer, a power source, a wire harness interface, and the like. The microcomputer has a known configuration including a CPU, a ROM, a RAM, a nonvolatile memory, an I / O, a CAN communication device, and the like.

The distance sensor 11 outputs target information (relative distance, relative speed, and direction) of the object to the DSS_ECU 25 for each cycle time.

The DSS_ECU 25 calculates a target acceleration (required driving force) based on the target information and the current vehicle speed and acceleration of the host vehicle detected by the wheel speed sensor 36, and transmits the target acceleration to the engine ECU 26 and the brake ECU 24. The target acceleration is a positive value or a negative value. If the target acceleration is a positive value, the engine ECU 26 performs acceleration control. If the target acceleration is a negative value and requires braking, the brake ECU 24 controls the brake ACT (actuator) 37 to decelerate. To do.

A method for calculating the target acceleration is well known and will be omitted. For example, the target acceleration is determined in consideration of the difference between the target inter-vehicle distance determined according to the speed and the current inter-vehicle distance, and the relative speed.

The engine ECU 26 determines the throttle opening according to the target acceleration, and controls the throttle motor 34 while monitoring the throttle opening detected by the throttle position sensor 35. Further, the engine ECU 26 determines the necessity of changing the gear position based on the upshift line and the downshift line determined for the vehicle speed and the throttle opening, and instructs the transmission 33 for the gear position if necessary. The transmission 33 may be any mechanism such as AT (automatic transmission) or CVT (Continuously Variable Transmission).

The brake ECU 24 controls the wheel cylinder pressure by controlling the opening / closing and opening of the valve of the brake ACT 37 according to the target acceleration (negative value). Since the brake ACT 37 increases, maintains, and reduces the wheel cylinder pressure of each wheel by the hydraulic pressure generated by the pump in the working fluid, it becomes possible to control the deceleration of the vehicle.

Further, when the inter-vehicle distance control function is operating and the brake ECU 24 stops the vehicle, that is, when the value of the wheel speed sensor 36 becomes 0, considering the possibility that the vehicle has not stopped, The inter-vehicle distance control function requests a target acceleration (negative value) and pressurizes the wheel cylinder pressure. This braking is referred to as “braking for stopping and holding”. When the vehicle is stopped by the inter-vehicle distance control function, it is assumed that the driver does not operate the brake pedal. Therefore, the stop maintaining function is activated after a predetermined time, not by depressing the brake pedal.

FIG. 4 shows an example of a functional block diagram of the vehicle control device 1. These functions are realized by the CPU of each ECU executing a program stored in the ROM and cooperating with various hardware.

As described so far, the vehicle control apparatus 1 of the present embodiment includes the ACC control unit 41 that controls the inter-vehicle distance control function, the BH control unit 42 that controls the vehicle stop maintaining function, and the S & S control unit 43 that controls the idling stop function. And a brake control unit 44 for controlling the brake ACT.

The ACC control unit 41 notifies the BH control unit 42 and the S & S control unit whether or not it is operating (ON / OFF). When the ACC control unit 41 determines that the vehicle has stopped, that is, when the value of the wheel speed sensor 36 becomes 0, the ACC control unit 41 performs “braking for holding stopped” to the braking control unit 44. Request the target acceleration (negative value). The braking control unit 44 pressurizes the wheel cylinder according to the requested target acceleration (negative value). Further, when the value of the wheel speed sensor 36 becomes 0, the ACC control unit 41 notifies the BH control unit 42 to that effect. Further, the ACC control unit 41 detects the start of the preceding vehicle and notifies the S & S control unit 43 of the start request.

When the BH control unit 42 obtains the stop notification, the BH control unit 42 requests the braking control unit 44 to maintain braking after a predetermined time (t [s]). Further, the BH control unit 42 notifies the ACC control unit 41 whether or not the vehicle stop keeping function is operating (ON / OFF).

The ACC control unit 41 instructs the braking control unit 44 to “brake for holding the stop” until the value of the wheel speed sensor becomes 0 and until the BH control unit 42 acquires the operation (ON) of the stop maintaining function. ”Is requested for the target acceleration (negative value). The target acceleration (negative value) for performing “braking to hold the vehicle stopped” is the amount by which the vehicle does not move when the engine 20 is restarted by the idling stop control until the BH control unit 42 is activated. Required to be able to secure.

When the engine 20 is restarted by the idling stop function, the wheel cylinder pressure for the amount of pressure that does not move the vehicle is, for example, (wheel cylinder pressure for the pressure increase) [MPa] = (P [N] / caliper piston area [mm ^ 2] / BEF [dimensionless]) / caliper braking effective radius [mm] * tire dynamic load radius [mm]) (* P [N] = torque converter capacity factor * torque converter torque ratio * 1 ^st gear ratio * Differential ratio / Tire radius * (Blow-up MAX speed ^ 2-Idle revision MIN ^ 2))

In addition, you may calculate dynamically the wheel cylinder pressure for the pressurization which does not move a vehicle. For example, the blow-up rotation speed is monitored, and the average of the past multiple blow-up rotation speeds is calculated. Further, the engine speed immediately before the engine is stopped is detected as the idle speed. Then, the wheel cylinder pressure for the pressurization is dynamically calculated based on the above formula.

Further, the target acceleration (negative value) for performing “braking for holding the vehicle stopped” is requested to the braking control unit 44 based on a map as shown in FIG. The target acceleration -α1 at t1 [s] immediately after the wheel speed sensor value becomes 0 is smaller in the negative direction than the subsequent target acceleration, and the target acceleration from t1 [s] to t2 [s] ( The amount of change in the target acceleration (negative value) from t2 [s] to t3 [s] is larger in the negative direction than the negative value), and the target acceleration (negative value) from t2 [s] to t3 [s] ), The amount of change in the target acceleration (negative value) from t3 [s] to t4 [s] is larger in the negative direction. That is, the target acceleration (negative value) for performing “braking for holding the vehicle stopped” is the amount of change per unit time of the target acceleration (negative value) after the value of the wheel speed sensor 36 becomes zero. The braking control unit 44 is requested to gradually increase in the minus direction. As a result, the amount of change in braking force per unit time immediately after the value of the wheel speed sensor becomes zero is smaller than the amount of change in braking force per unit time thereafter, and the value of the wheel speed sensor is 0. Then, the amount of change per unit time of the braking force increases.

Further, when the BH control unit 42 is activated at t4, the target acceleration −α4 at the time t4 [s] is maintained as the target acceleration. -α4 is a value that ensures a braking force equal to or greater than the braking force at which the host vehicle does not start when the engine is restarted by the idling stop control.

A transition diagram of the target acceleration is shown in FIG. By requesting the target acceleration as shown in FIG. 6 (a), the braking force changes as shown in FIG. 6 (b). That is, after the value of the wheel speed sensor 36 becomes 0, the braking force is increased until the braking force becomes larger than the driving force when the engine is restarted by the idling stop control. In addition, after the BH control unit 42 is activated, the braking force when the BH control unit 42 is activated from the non-actuated state is maintained.

FIG. 6C is a transition diagram of the change amount of the braking force per unit time. After the value of the wheel speed sensor 36 becomes 0, the amount of change per unit time of the braking force is increased. Further, after the BH is turned on, the change amount of the braking force per unit time is set to zero. In FIG. 6C, the amount of change in the braking force per unit time is increased at a constant increase rate from when the wheel speed sensor value becomes 0 until the BH control unit 42 operates. The increase rate may be changed from when the value of the wheel speed sensor becomes 0 until the BH control unit 42 operates.

In “Prior Art 1” and “Prior Art 2”, the amount of change in braking force per unit time is constant after the value of the wheel speed sensor becomes zero. In “Prior Art 1”, the amount of change in braking force per unit time is smaller than that in “Prior Art 2”. Therefore, the rise of the braking force is slow, and it takes time until the braking force becomes equal to or greater than the driving force at the time of engine restart. Therefore, at t4 [s], the braking force is not greater than the driving force at the time of engine restart ((b) in FIG. 6). In addition, “conventional technology 2” has a larger change amount per unit time of braking force than “conventional technology 1”. Therefore, at the time T [s] (when the vehicle is actually completely stopped), the braking force becomes larger than that of the “prior art 1” ((b) in FIG. 6). Therefore, after the value of the wheel speed sensor becomes 0, the shock when the vehicle actually stops completely increases.

On the other hand, in this embodiment, the amount of change per unit time of the braking force is increased after the value of the wheel speed sensor becomes zero. That is, the amount of change per unit time of the braking force immediately after the wheel speed sensor value becomes 0 is set small, and gradually the unit of braking force until the braking force exceeds the driving force at the time of restarting the engine. Increase the amount of change per hour. Therefore, the amount of change per unit time of the braking force immediately after the value of the wheel speed sensor becomes zero is smaller than the amount of change of the braking force per unit time thereafter. Therefore, when the value of the wheel speed sensor becomes 0 and it is determined that the vehicle has stopped, even if the vehicle has not stopped completely and the vehicle has moved slightly, The braking force is smaller than that of “Prior Art 2”. Thereby, the shock at the time of a vehicle stopping completely by the ACC control part 41 can be suppressed.

Further, by increasing the amount of change in the braking force per unit time, the braking force increases earlier compared to the case where the amount of change in the braking force per unit time is not increased. Therefore, the braking control unit 44 pressurizes the wheel cylinder earlier than the “prior art 1” until the braking force is equal to or higher than the driving force when the engine 20 is restarted by the idling stop function, and the braking force is increased. It is possible to prevent the vehicle from moving when the engine 20 is restarted by the idling stop function.

In addition, the BH control unit 42 and the S & S control unit 43 operate simultaneously with the ACC control unit 41, so that their operations are changed. First, the operation of the stop maintenance function is performed after a predetermined time (t [s]) has elapsed from the operation of the driver stepping on the brake pedal with a depressing force equal to or greater than the threshold value, from the notification that the vehicle has stopped from the ACC control unit 41. Switch to doing. Thereby, stop maintenance control can be performed even when the inter-vehicle distance control function is activated. Further, the BH control unit 42 notifies the S & S control unit of ON (operation) / OFF (release) of the vehicle stop keeping function.

Further, the S & S control unit 43 notifies the ACC control unit 41 of engine ON / OFF. Further, the S & S control unit 43 operates simultaneously with the ACC control unit 41, whereby the engine stop condition and the restart condition change. First, the stop condition is changed to “the vehicle speed is zero and the stop maintaining function is activated” instead of “the vehicle speed is zero and the brake pedal is depressed”. Thus, it is possible to reliably prevent the vehicle from moving when the engine 20 is restarted by the idling stop control. When the inter-vehicle distance control function is canceled by depressing the brake pedal, the inter-vehicle distance control function is canceled by depressing the brake pedal. Further, it is assumed that the brake pedal is not depressed when the inter-vehicle distance control function is activated. For this reason, when the inter-vehicle distance control function is operating, the S & S control unit 43 does not set “the brake pedal is depressed” as the engine stop condition. Further, the operation for maintaining the stop function is switched from the operation of depressing the brake pedal to the notification of “braking for confirmation of stop”. For this reason, when the inter-vehicle distance control function is activated, it is reasonable to set the engine stop condition as “the stop maintenance function has been activated”.

Further, when the inter-vehicle distance control function is activated, the host vehicle also starts following the start of the preceding vehicle, so the S & S control unit 43 needs to start the engine 20 even if the driver does not operate the accelerator pedal. . For this reason, the restart condition is changed as follows.
-The preceding vehicle has started-The accelerator pedal has been turned ON-The SOC of the battery 15 has fallen below the threshold-The brake boost negative pressure has risen above the threshold-The ACC control unit has been activated by the start operation of the ACC “The ACCC control unit is activated by the start operation of ACC” means that the ACC control unit is activated by the driver operating an ACC switch (not shown), for example.

FIG. 7 is an example of a diagram illustrating an operation procedure of the vehicle control device 1 of the present embodiment.

In this embodiment, since it is assumed that the inter-vehicle distance control function is in operation, the flowchart of FIG. 7 starts from a state in which the inter-vehicle distance control function is in operation.

When the value of the wheel speed sensor 36 is 0 during the operation of the inter-vehicle distance control function and it is determined that the vehicle has stopped (Yes in S110), the ACC control unit 41 determines whether the BH is ON (activated) / OFF (not activated). Is acquired and BH is OFF (inactive) (No in S120), a target acceleration (negative value) for performing “braking for holding the vehicle stopped” is calculated by, for example, FIG. 3A (S150). ). The calculated target acceleration is requested to the braking control unit 44 (S130). However, even if the value of the wheel speed sensor is 0, the vehicle may not actually stop completely and may be moving.

When the value of the wheel speed sensor is not 0 during the operation of the inter-vehicle distance control function (No in S110), the ACC control unit 41 calculates the target acceleration for performing the normal inter-vehicle distance control, assuming that the vehicle is traveling. (S140).

Further, when BH is ON (operation) (Yes in S120), a request is made to the braking control unit 44 without calculating the current target acceleration again (S130). By this operation, when the BH is ON (actuated), the braking control unit 44 maintains the braking force at a constant value, and prevents unnecessary operating noise and brake ACT without pressing the wheel cylinder more than necessary. Can be prevented.

As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited to such an Example at all, In the range which does not deviate from the summary of this invention, various deformation | transformation and substitution Can be added. For example, the engine start condition / engine stop condition of the S & S control unit or the stop maintaining function operation operation of the BH control unit 42 can be set as appropriate, and are not limited to those described in the present embodiment.

In this embodiment, the braking force is controlled by hydraulic pressure. However, in a vehicle in which the braking force is controlled by an electric motor, the pressure reduction control of this embodiment is executed by the electric motor. Further, when a part of the braking force is supplied by the electric motor, the pressurization control of this embodiment may be realized by either hydraulic pressure or electric brake.

1 Vehicle Control Device 11 Distance Sensor 20 Engine 24 Brake ECU
25 DSS_ECU
26 Engine ECU
41 ACC control unit 42 BH control unit 43 S & S control unit

Claims (1)

Inter-vehicle distance control means for controlling the inter-vehicle distance between the host vehicle and the preceding vehicle;
Engine stop / restart means for stopping the engine of the host vehicle when a predetermined stop condition is satisfied, and restarting the engine when a predetermined restart condition is satisfied;
In the vehicular control device, the inter-vehicle distance control means includes a braking control means for increasing the braking force until the driving force of the own vehicle becomes larger than the driving force of the own vehicle at the time of restart when the stop of the own vehicle is determined.
The braking control means increases the amount of change per unit time of the braking force until the braking force becomes larger than the driving force after the host vehicle stops.

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