JP7019252B2 - Vehicle control device - Google Patents

Description

The present invention has an idling stop control function that stops the engine when a predetermined engine stop condition is satisfied and restarts the engine when a predetermined engine restart condition is satisfied, and a constant speed while keeping the distance between the vehicle and the preceding vehicle constant. The present invention relates to a vehicle control device having a constant-speed traveling inter-vehicle distance control function for traveling and an electric parking brake control function for operating a parking brake when a predetermined parking condition is satisfied and releasing the parking brake when a predetermined start condition is satisfied.

Conventionally, in an idling stop vehicle, when the engine is started by operating the IG (ignition) switch, then idling stop control is executed until the engine is stopped by operating the IG switch off, and a predetermined engine stop condition is satisfied. Automatically stops the engine and automatically restarts the engine when a predetermined engine restart condition is satisfied.

In addition to such an idling stop control function, constant-speed traveling inter-vehicle distance control (hereinafter referred to as ACC (Adaptive Cruise Control)) that detects the inter-vehicle distance with the preceding vehicle and performs constant-speed traveling while keeping the inter-vehicle distance constant. A vehicle equipped with such a function has also been proposed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2004-152598 (paragraphs 0018-0054, etc.)

By the way, in addition to both the idling stop control and ACC (constant speed traveling vehicle-to-vehicle distance control) functions, in recent years, the parking brake is activated when a predetermined parking condition is satisfied, and the parking brake is applied when a predetermined parking release condition is satisfied. A vehicle equipped with an electric parking brake control function to release the vehicle has also been proposed. In such a vehicle, the idling stop control is controlled by an idling stop ECU (ECU: Electrical Control Unit) having a microcomputer configuration as an idling stop control unit. The ACC is controlled by an ECU with a microcomputer configuration as a constant-speed traveling vehicle-to-vehicle distance control unit, and the electric parking brake control is controlled by an electric parking brake ECU with a microcomputer configuration as an electric parking brake control unit. Information is exchanged with the ECU that controls the control of each unit by CAN (Controller Area Network) communication.

In this type of vehicle, if the preceding vehicle stops while the ACC is operating by the ECU that controls the ACC, the automatic brake is applied under the control of the ECU that controls the ACC, the own vehicle stops following the stop of the preceding vehicle, and the engine stops. When the conditions are met, the idling stop control by the idling stop ECU is activated and the engine is controlled to the stopped state, and the own vehicle stops even though the driver does not step on the brake pedal. It is determined that the parking condition is satisfied by the stop of the vehicle, the electric parking brake control is activated, the parking brake is automatically activated, and then the idling stop control by the idling stop ECU is activated.

However, since there is a so-called time lag of about several seconds between the stop of the own vehicle due to the operation of the ACC by the ECU that controls the ACC and the operation of the parking brake by the electric parking brake ECU, idling stop control is performed after the operation of the electric parking brake. Since the engine is operating for a few seconds until it operates, there is a problem that fuel consumption during that period is wasted.

According to the present invention, when the electric parking brake control and the idling stop control are activated after the own vehicle is stopped by the operation of the ACC, the idling stop control is started before the electric parking brake control is activated to consume fuel. The purpose is to suppress it.

In order to achieve the above object, the vehicle control device of the present invention performs idling stop control for stopping the engine when a predetermined engine stop condition is satisfied and restarting the engine when a predetermined engine restart condition is satisfied. The stop control unit, the constant-speed traveling vehicle-to-vehicle distance control unit that performs constant-speed traveling while keeping the inter-vehicle distance to the preceding vehicle constant, and the parking brake are activated when a predetermined parking condition is satisfied, and the predetermined parking release condition is satisfied. The idling stop control unit is provided with an electric parking brake control unit that releases the parking brake, and the own vehicle stops following the stop of the preceding vehicle under the control of the constant speed traveling vehicle-to-vehicle distance control unit. The vehicle control device that starts the idling stop control after the parking brake is activated by the electric parking brake control unit when the parking condition is satisfied includes an inter-vehicle distance detecting means for detecting the inter-vehicle distance with the preceding vehicle. The idling stop control unit is controlled by the constant-speed traveling vehicle-to-vehicle distance control unit, and when the own vehicle stops following the stop of the preceding vehicle, the inter-vehicle distance detected by the inter-vehicle distance detecting means is preset. When the distance is equal to or greater than a predetermined distance, the idling stop control is activated before the parking brake by the electric parking brake control unit is activated due to the establishment of the parking condition.

According to the present invention, when the own vehicle stops following the stop of the preceding vehicle under the control of the constant speed traveling vehicle-to-vehicle distance control unit, the inter-vehicle distance detected by the inter-vehicle distance detecting means is equal to or more than a preset predetermined distance. In the case of, after the own vehicle has stopped following the stop of the preceding vehicle by the control of the constant speed traveling inter-vehicle distance control unit, and before the electric parking brake control by the electric parking brake control unit is activated due to the establishment of the parking condition. In addition, since the idling stop control is activated, even if there is a time delay of about several seconds between the time when the own vehicle is stopped due to the operation of the constant speed traveling vehicle distance control and the time when the electric parking brake control is activated, the constant speed traveling vehicle distance is activated. Since the engine is stopped by the idling stop control immediately after the own vehicle is stopped by the control of the distance control unit, wasteful fuel consumption as in the conventional case can be suppressed.

It is a block diagram of one Embodiment of the vehicle control device of this invention. It is a flowchart for operation explanation of FIG.

In order to explain the present invention in more detail, one embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

FIG. 1 shows a block configuration of a vehicle control device provided in an idling stop vehicle 1, and the idling stop vehicle 1 is a lead battery having a relatively small capacity of 12 V as a power source in order to reduce the weight and size. 2 is provided. The negative electrode terminal of the battery 2 is connected to the vehicle body of the idling stop vehicle 1.

In FIG. 1, 3 is an engine of an idling stop vehicle 1, 4 is a CVT on the transmission side of the engine 3, and a torque converter (including a lockup clutch mechanism) 5 is interposed with the engine 3.

Reference numeral 6 is a starter for starting the engine 3, and power is supplied from the battery 2 via the two relays 7a and 7b. Here, one relay 7a is on / off controlled by the engine ECU described later when the IG switch is turned on / off, and the other relay 7b is controlled on / off by the idling stop ECU described later when the engine is stopped and restarted in the idling stop control. Reference numeral 8 denotes a battery sensor provided close to the battery 2 between the positive electrode terminal of the battery 2 and the relays 7a and 7b, and detects the temperature and the current of the battery 2. Reference numeral 9 is an alternator in which the rotational force of the engine 3 is transmitted via the belt 10, and the battery 2 is charged by the power generation output during traveling or the like.

11 is an idling stop ECU corresponding to an idling stop control unit that controls idling stop control, 12 is an engine ECU that controls engine control, and 13 is an ABS ECU that controls brake ABS (antilocked braking system) that prevents skidding and spinning by automatic brake control. , 14 is a CVT ECU that controls CVT, 15 is a camera ECU that is provided at the front of the vehicle and controls a CCD camera (not shown) that shoots the preceding vehicle, and processes images taken by the camera. 16 is an electric parking brake (hereinafter referred to as electric parking brake). , EPB (Electric Parking Brake)) control, each ECU 11 to 15 is formed by a microcomputer or the like, and information is exchanged via a communication bus 17 such as a CAN or the like.

Here, the camera ECU 15 processes the captured image of the CCD camera to derive the inter-vehicle distance to the preceding vehicle, the relative speed of the preceding vehicle, and the acceleration. The function of the camera ECU 15 corresponds to the "inter-vehicle distance detection means" in the present invention. Then, when the execution of ACC is selected by the switch operation by the driver or the like, the engine output control by the engine ECU 12 and the automatic braking by the ABS ECU 13 are performed in order to perform constant speed running while keeping the distance between the vehicle and the preceding vehicle constant. Control is performed, and the engine ECU 12, ABS ECU 13, and camera ECU 15 constitute a constant-speed traveling vehicle-to-vehicle distance control unit of the present invention that executes ACC (constant-speed traveling vehicle-to-vehicle distance control). Reference numeral 19 is a wheel speed sensor that gives the ABSECU 13 detection information of the vehicle speed, and 20 is a hydraulic pressure sensor that gives the ABSECU 13 the detection information of the brake fluid pressure of the master cylinder of the brake mechanism.

Further, the EPCECU 16 activates the parking brake when a predetermined parking condition is satisfied, and releases the parking brake when a predetermined parking release condition is satisfied. For example, the own vehicle (idling stop vehicle) detected by the wheel speed sensor 19. If the vehicle speed of 1) is 0 km / h, the parking brake is activated assuming that the predetermined parking condition is satisfied, and the own vehicle (idling stop vehicle 1) detected by the wheel speed sensor 19 as the driver depresses the accelerator pedal. ) When the vehicle speed is no longer 0 km / h, the parking brake is released assuming that the predetermined parking release condition is satisfied. The parking condition and the parking cancellation condition are not limited to whether or not the vehicle speed is zero as described above.

Then, to explain the schematic control and operation of the idling stop vehicle 1, the driver turns on the ignition (IG) switch (not shown) to command the engine start, so that the signal of the IG switch is, for example, the communication bus 17. Is input to the idling stop ECU 11 and the engine ECU 12, and based on this input, the engine ECU 12 momentarily energizes and turns on the relay 7b, supplies power to the battery 2 to the starter 6, starts and stops the starter 6. Start the engine 3 (first start). Once the engine 3 is started and the battery 2 is fully charged by the generated power of the alternator 9, the idling stop ECU 11 executes the idling stop control until the engine 3 is stopped by turning off the IG switch. do.

The idling stop ECU 11 has information on the engine ECU 12 (engine information such as engine rotation speed and cooling water temperature), information on the battery 2 current, temperature, etc., detected vehicle speed of the ABS ECU 13, master cylinder pressure, etc. via the communication bus 17. Information, lock-up clutch information of the CVT ECU 14, information on switches in various parts of the vehicle such as a stop lamp switch and a courtesy switch (not shown) are input.

Then, based on this information, the idling stop ECU 11 during idling stop control detects that the driver depresses the brake pedal according to the red light of the traffic signal and the master cylinder pressure is equal to or higher than the predetermined depressing pressure. By confirming that the predetermined stop conditions for idling stop control (for example, the condition that the stop lamp is lit and the vehicle speed is lower than the specified vehicle speed) are satisfied, the vehicle speed drops below the specified vehicle speed even if the vehicle does not stop completely. Then, the engine ECU 12 is instructed to stop the engine, and the engine ECU 12 throttles the fuel throttle to automatically stop the engine 3.

Next, when the driver takes his / her foot off the brake pedal such as when the traffic signal changes to a green light and detects that the master cylinder pressure has dropped to a predetermined opening pressure, the idling stop vehicle 1 performs a predetermined restart of idling stop control. By confirming that the conditions (for example, the condition that the stop lamp is off and the door is closed) are satisfied, the engine ECU 12 momentarily energizes the relay 7b and turns it on based on the restart command from the idling stop ECU 11. , The power of the battery 2 is supplied to the starter 6 to start the starter 6, and the stopped engine 3 is automatically restarted.

After that, the automatic stop of the engine 3 based on the satisfaction of the predetermined stop condition during deceleration and the automatic restart of the engine 3 based on the satisfaction of the predetermined restart condition are alternately performed.

By the way, for example, when ACC execution is selected by a switch operation by a driver when traveling on a highway, images of a preceding vehicle during acceleration traveling, constant speed traveling, and deceleration traveling of the idling stop vehicle 1 are shown. The image is taken by the omitted CCD camera, the image taken by the camera is processed by the camera ECU 15, and the relative speed, acceleration, etc. of the preceding vehicle are derived from the inter-vehicle distance to the preceding vehicle, the time change of the inter-vehicle distance, etc. ACC (constant speed travel distance control) is performed so that the own vehicle travels at a constant speed while keeping the distance between the vehicle and the preceding vehicle constant by the engine control and the automatic brake control by the ABSECU 13. In addition, when the preceding vehicle stops due to traffic congestion on the road, the own vehicle (idling stop vehicle 1) also stops due to the automatic brake control in the ACC.

Then, when the preceding vehicle is stopped and the own vehicle (idling stop vehicle 1) is also stopped by the automatic brake control while the ACC is operating, the vehicle speed of the own vehicle becomes 0 km / h and the parking condition in the EPB control is satisfied. , EPB ECU 16 starts executing EPB control, the electric parking brake is automatically activated, and when the own vehicle is completely stopped, the idling stop control is activated by the idling stop ECU 11 even if the driver does not depress the brake pedal. Then the engine 3 is stopped.

At this time, when the preceding vehicle is stopped and the own vehicle (idling stop vehicle 1) is stopped by the automatic brake control during the operation of the ACC, the inter-vehicle distance L with the preceding vehicle detected by the camera ECU 15 is predetermined. If the predetermined distance is Lt or more, as described above, even if the parking condition in the EPB control is satisfied at the vehicle speed of the own vehicle 0 km / h, the EPB control by the EPB ECU 16 does not start execution, and the idling stop control by the idling stop ECU 11 Is started to execute and the engine 3 is stopped, and then EPB control by the EPCECU 16 is started to be executed and the electric parking brake is activated.

In this way, by activating the idling stop control prior to the EPB control, the EPB is activated by stopping the own vehicle by the ACC, and then the idling stop control is activated after the stop of the own vehicle by the ACC. , The engine can be stopped immediately by idling stop control to suppress fuel consumption.

By the way, the above-mentioned predetermined distance Lt means that even if the own vehicle jumps out due to some factor between the time when the own vehicle (idling stop vehicle 1) reaches 0 km / h and the time when the idling stop control is activated. It is desirable to experimentally obtain and set a distance (0.5 m to 1 m) that does not cause a collision with the preceding vehicle.

In addition, when the own vehicle stops on a downhill, the amount of jumping out of the own vehicle may increase due to the sliding down due to the road slope, which may cause a collision with the preceding vehicle. , Even when the oil temperature of the transmission is low, the engine 3 may blow up and the amount of protrusion of the own vehicle may increase. Therefore, when the downward slope of the road on which the own vehicle stops is greater than the predetermined value. When the engine water temperature, engine oil temperature, and transmission oil temperature are lower than the temperature at which the engine is likely to blow up, the above-mentioned predetermined distance Lt should be switched to a value longer than usual (0.5 m to 1 m). It is desirable to control.

Next, the operation of the idling stop ECU 11 and the EPBE ECU 16 will be described with reference to the flowchart of FIG.

Now, it is determined whether or not the vehicle is stopped by the ACC, that is, whether or not the preceding vehicle is stopped and the own vehicle (idling stop vehicle 1) is stopped by the automatic brake control (step S1). If the determination result is NO, step S1 is repeated until the determination result becomes YES, and if the determination result is YES, the inter-vehicle distance L with the preceding vehicle detected by the camera ECU 15 is a predetermined distance Lt set in advance. It is determined whether or not it is the above (step S2).

If the determination result in step S2 is YES, the idling stop control by the idling stop ECU 11 is activated (step S3), then the EPB control by the EPB ECU 16 is activated (step S4), and the EPB (electric parking brake) is automatically activated. The operation is terminated. In this way, if the distance L from the preceding vehicle to the preceding vehicle is Lt or more after the own vehicle is stopped by ACC, the own vehicle is stopped by operating the idling stop control before the EPB control to stop the engine. Even if it jumps out, it is possible to prevent the vehicle from colliding with the preceding vehicle and to give priority to stopping the engine to reduce fuel consumption.

On the other hand, if the inter-vehicle distance L with the preceding vehicle is shorter than the predetermined distance Lt in the determination in step S2 and the determination result is NO, the idling stop ECU 11 determines after the EPB control by the EPB ECU 16 is activated (step S5). The idling stop control is activated (step S6), and then the operation ends. In this case, the idling stop control does not operate and the engine remains operating during the delay time of about several seconds from the stop of the own vehicle by ACC to the application of EPB by EPB control, so fuel consumption during that period is wasted. However, by operating the EPB control first, it is possible to prevent a rear-end collision with the preceding vehicle.

Therefore, according to the present embodiment, when the own vehicle (idling stop vehicle 1) stops following the stop of the preceding vehicle by ACC, the inter-vehicle distance L detected by the camera ECU 15 is equal to or larger than a preset predetermined distance Lt. In this case, after the own vehicle is stopped following the stop of the preceding vehicle by the ACC, the idling stop control is activated before the EPB control is activated by the EPCECU 16, so that the own vehicle is stopped by the operation of the ACC. Even if there is a time delay of about a few seconds before the EPB control is activated, the engine is stopped by the idling stop control immediately after the own vehicle is stopped by the ACC, so wasteful fuel consumption as in the past is suppressed. be able to.

Further, when the own vehicle stops following the stop of the preceding vehicle by the ACC and the inter-vehicle distance L detected by the camera ECU 15 is shorter than the preset predetermined distance Lt, the EPB control by the EPBE ECU 16 is activated. Since the idling stop control by the idling stop ECU 11 is operated, it is possible to prevent a rear-end collision with the preceding vehicle by operating the EPB control first.

The present invention is not limited to the above-described embodiment, and various modifications can be made other than those described above as long as the present invention is not deviated from the gist thereof.

For example, as described above, when the downhill slope of the road on which the own vehicle stops is greater than a predetermined value, or when the engine water temperature, engine oil temperature, and transmission oil temperature are higher than the temperatures at which the engine is likely to blow up. When it is low, the predetermined distance Lt described above may be switched to a value longer than usual (0.5 m to 1 m). By doing so, even if there is a risk that the amount of jumping out of the own vehicle will be large, by activating the idling stop control before EPB, even if the own vehicle should jump out, it will collide with the preceding vehicle. It is possible to suppress fuel consumption by giving priority to engine stop while preventing the above.

The present invention can be applied to a vehicle control device having an idling stop function, an ACC (constant speed traveling vehicle-to-vehicle distance control) function, and an EPB (electric parking brake) control function.

1 Idling stop vehicle 3 Engine 11 Idling stop ECU (idling stop control unit)
12 Engine ECU (Constant speed traveling vehicle-to-vehicle distance control unit)
13 ABSECU (Constant-speed traveling vehicle-to-vehicle distance control unit)
15 Camera ECU (inter-vehicle distance detection means, constant-speed traveling inter-vehicle distance control unit)
16 EPBECU

Claims (1)

When the predetermined engine stop condition is satisfied, the engine is stopped, and when the predetermined engine restart condition is satisfied, the engine is restarted. It is equipped with a constant-speed traveling inter-vehicle distance control unit that performs high-speed travel, and an electric parking brake control unit that operates a parking brake when a predetermined parking condition is satisfied and releases the parking brake when a predetermined parking release condition is satisfied.
The idling stop control unit is controlled by the constant-speed traveling vehicle-to-vehicle distance control unit to stop the own vehicle following the stop of the preceding vehicle, and when the parking condition is satisfied, the parking brake by the electric parking brake control unit is used. In the vehicle control device that starts the idling stop control after the engine is activated.
Equipped with an inter-vehicle distance detection means that detects the inter-vehicle distance with the preceding vehicle,
The idling stop control unit is
When the own vehicle stops following the stop of the preceding vehicle by the control of the constant speed traveling vehicle-to-vehicle distance control unit, when the inter-vehicle distance detected by the inter-vehicle distance detecting means is equal to or more than a preset predetermined distance. A vehicle control device, characterized in that the idling stop control is activated before the parking brake by the electric parking brake control unit is activated due to the establishment of the parking condition.

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