JP5910414B2 - Brake control device for vehicle - Google Patents

Description

  The present invention relates to a vehicle brake that performs brake hold (hereinafter referred to as BH) control for maintaining the vehicle stopped by using both an electric parking brake (hereinafter referred to as EPB (Electric parking brake)) and a hydraulic brake. The present invention relates to a control device.

  Conventionally, in Patent Document 1, in a vehicle equipped with a hydraulic brake and an EPB, the brake force generated when the vehicle is stopped is held by the hydraulic pressure holding function of the hydraulic brake while executing the BH. Accordingly, a technique for switching to a braking force by EPB is disclosed. Specifically, the hydraulic pressure is maintained until a predetermined set time elapses by the hydraulic pressure holding function of the hydraulic brake, and the brake force is generated by switching to EPB after the set time elapses. Further, by detecting the surrounding environment of the vehicle by the surrounding environment detecting means and determining whether or not the place where the vehicle is currently stopped is “a situation in which a quick start is required”, the EPB can be controlled from the hydraulic brake. Whether or not to switch to. The “situation requiring quick start” here means that the stop position is “near an intersection”, “congestion area”, or “meeting point”. In other words, the hydraulic brake is switched to EPB.

JP 2008-132877 A

  However, it is not a good idea from the viewpoint of power consumption to simply switch to EPB after a set time has elapsed since the start of holding the hydraulic pressure by the hydraulic brake. That is, once the EPB is operated, a stable braking force can be maintained for a long time without power consumption thereafter, but power consumption during operation is relatively large. On the other hand, the hydraulic brake holds the hydraulic pressure generated when the vehicle is stopped by driving various solenoid valves provided in the brake hydraulic pressure circuit, and maintains the braking force. Although the power consumption is relatively small, the power is always consumed while the braking force is maintained.

  Therefore, in the situation where the vehicle starts immediately after the vehicle stops, the power consumption can be reduced by using only the hydraulic brake without switching from the hydraulic brake to the EPB. On the other hand, if the vehicle is stopped for a long time after stopping, the power consumption can be reduced by switching from the hydraulic brake to the EPB.

  However, the technique described in Patent Document 1 simply switches to EPB after a predetermined set time has elapsed since the start of hydraulic pressure retention by the hydraulic brake, or depending on the surrounding environment such as the vicinity of an intersection, a traffic jam area, or a merging point, Whether to switch from the hydraulic brake to the EPB uniformly is determined. For this reason, no consideration is given to whether the vehicle is going to start immediately after it stops or whether the vehicle will stop for a long time. Therefore, it is desirable to be able to switch from the hydraulic brake to the EPB depending on how long the vehicle stop state may continue.

  However, EPB is less responsive than hydraulic brake, and it takes time to release the brake force from the state where the brake force is generated by EPB. On the contrary, in the case of the hydraulic brake, the responsiveness is good, and the generation operation and the release operation of the braking force are instantaneously possible. For this reason, even if there is a possibility that the stop state of the vehicle may continue for a relatively long time, if there is an urgent situation in which the vehicle is to be quickly transferred from the stop state to the start state, the hydraulic brake is used instead of the EPB. It is preferable that the braking force is generated by the above.

  In view of the above points, the present invention can further reduce power consumption when generating a braking force for executing BH using both a hydraulic brake and an EPB in BH control. A first object is to provide a vehicle brake control device. It is a second object of the present invention to provide a vehicular brake control device that can release a braking force with better responsiveness in a situation that requires urgentness while reducing power consumption.

  In order to achieve the above object, according to the first aspect of the present invention, the information acquisition means (100) acquires the surrounding information of the vehicle and the brake force generation target setting means (110 to 150) acquires the information. As a target for generating a braking force when maintaining the stop state of the vehicle, the stop prediction time (T3) at which the vehicle is predicted to stop is calculated from the vehicle surrounding information acquired by the means (100). If the time (T3) is larger than a preset threshold, EPB (3) is set, and if it is smaller, the hydraulic brake (2) is set. Then, either one of the hydraulic brake (2) and EPB (3) is actuated by the brake force generation means (210-230) according to the setting content of the brake force generation target setting means (110-150). Thus, the braking force is generated and the vehicle is kept stopped.

  Thus, the surrounding information of the vehicle is acquired, the predicted stop time (T3) of the vehicle is calculated, and braking is performed using either the hydraulic brake (2) or the EPB (3) from the predicted stop time (T3). It is determined whether the power generation is smaller when the force is generated. Thereby, in the BH control, when the generation of the braking force for executing the BH is performed using both the hydraulic brake (2) and the EPB (3), the power consumption can be further reduced. .

  For example, as described in claim 2, the information acquisition means (100) acquires information related to traffic lights at intersections where the vehicle stops as surrounding information, and the brake force generation target setting means (110 to 150) acquires information. Based on the information on the traffic signal obtained by the means (100), the predicted stop time (T3) at which the vehicle is predicted to stop at the intersection is calculated by the red signal of the traffic signal. In addition, as described in claim 3, the information acquisition means (100) acquires information on a crossing breaker at which the vehicle stops as surrounding information, and the brake force generation target setting means (110-150) Based on the information on the circuit breaker acquired by the acquisition means (100), the estimated stop time (T3) at which the vehicle is predicted to stop at the level crossing is calculated according to the circuit breaker signal.

  As shown in these figures, when the vehicle stops due to a red signal from the traffic light or a shut-off signal from the circuit breaker, braking force is applied using either the hydraulic brake (2) or EPB (3) from the predicted stop time (T3). The effect according to claim 1 can be obtained by determining whether or not the power consumption is smaller when the power is generated.

  In the invention according to claim 4, the braking force generation target setting means (110 to 150) determines whether or not the vehicle is in a situation that requires urgency to quickly shift from the stop state to the start state. Even if the judgment means (120, 130) is included and the estimated stop time (T3) is larger than the threshold, the vehicle is stopped when the urgency judgment means (120, 130) determines that the situation requires urgency. The hydraulic brake (2) is set as a target for generating a braking force when maintaining the state.

  As described above, it is determined whether to use the hydraulic brake (2) or the EPB (3) depending on the presence or absence of urgency, not simply based on the estimated stop time (T3). For this reason, when urgency is required, the hydraulic brake (2) is set, and the braking force can be released with good responsiveness.

  For example, as in the invention described in claim 5, the information acquisition means (100) acquires information about the direction indicator, and the urgency determination means (120) acquires the information acquisition means (100). When a right turn instruction is issued based on information on the direction indicator, it is preferable to determine that the situation requires urgency and set the hydraulic brake (2). Further, as in the invention described in claim 6, the information acquisition means (100) acquires information on the rear vehicle, and the urgency determination means (130) acquires the information acquired by the information acquisition means (100). It is preferable that the hydraulic brake (2) is set by determining that the situation requires urgency when a high-speed vehicle is approaching from behind based on information on the vehicle.

  In the invention according to claim 7, the information acquisition means (100) acquires information related to the preceding vehicle, and the brake force generation target setting means (110 to 150) acquires the forward direction acquired by the information acquisition means (100). Based on the information regarding the vehicle and the surrounding information, the estimated stop time (T3) is corrected according to the number of vehicles ahead and the distance from the stop position of the earliest vehicle to the host vehicle.

  If the preceding vehicle is in a stopped state and the host vehicle is away from the stop position (that is, the stop line) of the earliest vehicle, after the traffic light changes from a red signal to a green signal, Even after being released, the vehicle cannot start for a while. In such a situation, the estimated stop time (T3) is corrected accordingly according to the number of vehicles ahead and the distance from the stop position of the earliest vehicle to the host vehicle. The estimated stop time T3 can be set.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

1 is a block diagram illustrating an entire system to which a vehicle brake control device according to a first embodiment of the present invention is applied. It is the flowchart which showed the detail of the brake force generation | occurrence | production target setting process in a BH control process. It is the flowchart which showed the detail of the brake force generation | occurrence | production control process in a BH control process.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 is a block diagram showing the entire system to which the vehicle brake control device according to the present embodiment is applied. Hereinafter, an outline of a system to which the vehicle brake control device is applied will be described with reference to FIG.

  As shown in FIG. 1, in the present embodiment, BH control is performed using a system including a brake ECU 1, a hydraulic brake 2, an EPB 3, a navigation ECU 4, an in-vehicle communication device 5, a meter ECU 6, and an in-vehicle camera 7. In the case of this embodiment, the brake ECU 1 of these constitutes a vehicle brake control device, and the brake ECU 1 executes BH control.

  The brake ECU 1 executes ABS control by calculating each wheel speed, calculating a vehicle speed (estimated vehicle body speed) based on a detection signal from a wheel speed sensor (not shown), and performing a brake operation state, an accelerator operation state, and a vehicle. The brake control is performed by executing the BH control based on the stop state or the like. For example, the brake ECU 1 controls the brake hydraulic pressure applied to a wheel cylinder (hereinafter referred to as W / C) provided in each wheel by controlling the hydraulic brake 2 during ABS control, and the wheel is locked. To avoid. Further, the brake ECU 1 determines whether it is preferable to generate the braking force using the hydraulic brake 2 or the EPB 3 during the BH control, and generates the braking force according to the stop state of the vehicle or the surrounding situation. Is set so that BH according to the surrounding situation can be performed while reducing power consumption.

  Further, the brake ECU 1 inputs various information from the navigation ECU 4 and the meter ECU 6, and executes BH control based on the information. Information input from the navigation ECU 4 includes information on traffic lights installed at intersections where the vehicle has stopped, information on distances from the traffic lights to the host vehicle, and information indicating the state of the front vehicle and the rear vehicle. Information input from the meter ECU 6 includes information on a direction indicator. Furthermore, the brake ECU 1 can also input information on traffic lights installed at intersections and information indicating the states of the front vehicle and the rear vehicle from the peripheral images taken by the in-vehicle camera 7.

  In the present embodiment, the ECU for controlling the hydraulic brake 2 and the EPB 3 is only the brake ECU 1, but these may be controlled by separate ECUs.

  The hydraulic brake 2 is a service brake that generates a braking force by generating a brake hydraulic pressure with respect to W / C of each wheel through a brake hydraulic pressure circuit. During normal braking, the hydraulic brake 2 generates brake hydraulic pressure in a master cylinder (hereinafter referred to as M / C) based on the operation of a brake operating member such as a brake pedal by a driver. Brake force is generated by telling

  Further, during the ABS control, the hydraulic brake 2 is driven based on a control signal from the brake ECU 1 by driving an actuator provided in the brake hydraulic circuit, specifically various electromagnetic valves and a pump driving motor. Thus, the brake fluid pressure applied to the W / C is controlled so that the wheels can be prevented from locking. When the brake force is generated by the hydraulic brake 2 during the BH control, various electromagnetic valves provided in the brake hydraulic circuit, specifically, each W, based on a control signal from the brake ECU 1 are used. By driving a control valve provided corresponding to / C, the brake fluid pressure applied to W / C is maintained. Thereby, based on the hydraulic pressure holding function of the hydraulic brake 2, the braking force generated when the vehicle is stopped can be held. Since various electromagnetic valves, pumps, pump driving motors, and the like provided in the hydraulic brake 2 are well known in the art, details thereof are omitted here.

  The EPB 3 drives the electric actuator based on the power supply and generates a parking brake force by bringing the friction material into contact with the friction material. EPB3 can hold | maintain a parking brake force, even if it stops the electric power supply to an electric actuator in that state, and stops an electric actuator. Further, when releasing the parking brake force, the EPB 3 drives the electric actuator in the release direction to separate the friction material from the friction target material and release the parking brake force.

  For example, the EPB 3 is configured to include an electric motor, a gear mechanism, a nut (propulsion shaft), a piston, and the like. In such a configuration, when the electric motor is rotated in the forward direction, the rotation is attenuated by the gear mechanism and converted into a straight movement of the nut screwed into the male screw groove of the rotation shaft of the gear mechanism. Then, by moving the piston along with the straight movement of the nut, a brake pad, which is a friction material attached to the tip of the piston, is pressed against a brake disk, which is a friction material, and parking brake force is generated. Even after the electric motor is stopped, the parking brake force is held based on the frictional force generated by the engagement between the nut and the male screw groove. Further, when the electric motor is rotated in the reverse direction, the nut is moved in the direction opposite to the piston, and accordingly, the piston and the brake pad are moved in the same direction. And the brake pad attached to the front-end | tip of a piston is spaced apart from a brake disc, and the generated parking brake force is cancelled | released.

  The navigation ECU 4 is used for performing road guidance and the like in the navigation system. In the present embodiment, the navigation ECU 4 is used for information acquisition using a communication function with the outside in the navigation system. Specifically, in this embodiment, the navigation ECU 4 acquires information on traffic lights installed at intersections where the vehicle has stopped, information on the positional relationship of the host vehicle, information indicating the state of the front vehicle and the rear vehicle, and the like. ing. Examples of the information related to the traffic light include information such as the duration of the red light of the traffic light, the elapsed time from when the traffic light became red, and the position of the traffic light. The information on the positional relationship of the host vehicle includes the position of the host vehicle on the map, and the distance from the traffic signal to the host vehicle based on the traffic signal position information and the host vehicle position information included in the traffic signal information. Information about can be obtained. Information indicating the state of the front vehicle and the rear vehicle includes information such as whether the front vehicle is in a stopped state or whether the rear vehicle is approaching the host vehicle at a high speed.

  The in-vehicle communication device 5 has a function of performing communication with the outside of the vehicle, and is built in the navigation system or separately provided in the vehicle. The above-described navigation ECU 4 obtains the various information through the in-vehicle communication device 5. The in-vehicle communication device 5 includes an antenna, and the above-described various information is acquired by communicating with the in-vehicle communication device 9 provided in the roadside device 8 and other vehicles through the antenna. In other words, by performing road-to-vehicle communication with the roadside device 8 provided on the road side, information related to the traffic signal possessed by the roadside device 8 is acquired, and the vehicle-mounted communication device 9 provided in another vehicle and vehicle-to-vehicle communication. The vehicle speeds of the vehicle ahead and the vehicle behind are acquired.

  The meter ECU 6 is a part that handles various signals to be displayed on the meter. Since the meter ECU 6 also handles information related to the operation status of the direction indicator, in the present embodiment, the brake ECU 1 obtains information related to the operation status of the direction indicator from the meter ECU 6.

  The in-vehicle camera 7 captures the vehicle periphery including the front and rear of the vehicle, and transmits the captured peripheral image to the brake ECU 1. Here, the in-vehicle camera 7 is used. However, any information can be used as long as it can acquire information about the front vehicle and the rear vehicle. For example, a laser radar used for ACC (active cruise control) control is used instead of the in-vehicle camera 7. It can also be used.

  BH control by the brake ECU 1 is executed using the system configured as described above. Details of the BH control will be described with reference to FIGS.

  FIG. 2 is a flowchart showing details of the brake force generation target setting process in the BH control process. FIG. 3 is a flowchart showing details of the brake force generation control process in the BH control process. Each of the processes shown in FIGS. 2 and 3 is executed independently as a BH control process, and is executed every predetermined control period.

  In the brake force generation target setting process shown in FIG. 2, in the BH control, whether the brake force generated to execute the BH and maintain the stop state of the vehicle is generated by either the hydraulic brake 2 or the EPB 3 And set the target to generate the braking force. In the braking force generation control process shown in FIG. 3, the setting contents in the braking force generation target setting process shown in FIG. 2 are read, and the braking force is generated for either the hydraulic brake 2 or the EPB 3 based on the setting contents. To perform the operation.

  First, when the brake force generation target setting process shown in FIG. 2 is executed, various information input processes are performed in step 100. In this process, the brake ECU 1 acquires the various information described above from the navigation ECU 4 and the meter ECU 6, and acquires information related to the traffic signal installed at the intersection using the peripheral image input from the in-vehicle camera 7.

  Thereafter, the process proceeds to step 110, and the power consumption is compared with the hydraulic brake 2 or the EPB 3 that requires less power consumption. The power consumption of the EPB 3 is lower than that of the hydraulic brake 2. Judge whether the situation is small and advantageous.

  Here, which of the power consumptions of the hydraulic brake 2 and the EPB 3 is less used depends on how long the stop time of the vehicle is. That is, once the EPB 3 is operated, a stable braking force can be maintained for a long time without power consumption thereafter, but the power consumption during operation is relatively large. On the other hand, the hydraulic brake 2 maintains the braking force generated when the vehicle is stopped by driving various electromagnetic valves provided in the brake hydraulic circuit, but the power consumption during operation is compared. Although it is small, the electric power is always consumed while the braking force is maintained. For this reason, the EPB 3 is more advantageous when the vehicle is stopped for a predetermined time or more, and the hydraulic brake 2 is more advantageous when the time is less than the predetermined time.

  For this reason, in step 110, a predetermined time during which EPB3 is advantageous in that it consumes less power than hydraulic brake 2 is set as a threshold value, and when the vehicle stops due to a red light at an intersection, the estimated stop time By determining whether or not the threshold value is exceeded, it is determined whether or not EPB3 is more advantageous.

  The estimated stop time is calculated based on the information on the traffic signal acquired in step 100. Specifically, using the duration T2 of the red signal of the traffic light at the intersection and the elapsed time T1 after the red signal, the predicted stop time T3 is the time obtained by subtracting the elapsed time T1 from the duration T2. Accordingly, the predicted stop time T3 of the vehicle can be calculated. When the predicted stop time T3 is long, the EPB3 is advantageous because it consumes less power, and when it is short, the hydraulic brake 2 consumes less power. Can be determined as advantageous.

  Further, as described above, the estimated stop time may be set to a time obtained by simply subtracting the elapsed time T1 from the duration time T2, but it relates to information indicating the state of the preceding vehicle and the distance from the traffic light to the host vehicle. You may correct | amend based on information. That is, after the traffic signal changes from a red signal to a green signal when the preceding vehicle is in a stopped state and the host vehicle is away from the stop position (that is, the stop line) of the earliest vehicle among the preceding vehicles. However, the vehicle cannot start for a while. For this reason, in such a situation, the estimated stop time T3 may be the time obtained by adding the correction time to the time obtained by subtracting the elapsed time T1 from the duration T2. As a result, a more accurate estimated stop time T3 can be set. The correction time is set according to the number of front vehicles that are stopped and the distance from the traffic signal to the host vehicle, and may be a fixed time. The more the number of vehicles ahead, or the traffic signal to the host vehicle. The longer the distance is, the longer it may be.

  If the determination in step 110 is affirmative, the process proceeds to step 120 or 130 to determine whether or not the situation requires urgency. That is, EPB has poor responsiveness compared to hydraulic brake, and it takes time to release the braking force from the state where the braking force is generated by EPB. On the contrary, in the case of the hydraulic brake, the responsiveness is good, and the generation operation and the release operation of the braking force are instantaneously possible. For this reason, even if the estimated stop time T3 is relatively long and the EPB3 is advantageous in that it consumes less power, if the situation requires urgency, the brake force is not applied by the hydraulic brake 2 but by the EPB3. It is preferable to generate this.

  Therefore, as a situation requiring urgency, it is determined in step 120 whether there is a right turn instruction, and in step 130, it is determined whether a high-speed vehicle is approaching from behind. In the case of giving a right turn instruction, even if the vehicle is stopped at an intersection, there is a possibility of starting immediately. For example, even a red signal may start based on a right turn instruction display signal. In addition, when a high-speed vehicle is approaching from behind, it may be desired to start the vehicle to avoid it. Therefore, in these cases, the situation is urgent.

  In addition, the presence or absence of a right turn instruction can be determined based on the information related to the direction indicator acquired from the meter ECU 6. Moreover, about the high-speed vehicle from back, the information which shows the state of the back vehicle obtained through the vehicle-to-vehicle communication can be acquired from navigation ECU4, or it can determine based on the surrounding image from the vehicle-mounted camera 7. FIG.

  Then, if both steps 120 and 130 are negatively determined and the situation is not urgent, the process proceeds to step 140, and in EPB setting, that is, in BH control, BH is executed and the vehicle is kept stopped. In addition, a setting is made to generate a braking force in EPB3. Further, if the determination is affirmative in either step 120 or step 130 and the situation requires urgency, the process proceeds to step 150, and in the hydraulic brake setting, that is, in the BH control, BH is executed to stop the vehicle. Is set to generate a braking force by the hydraulic brake 2. In this way, the brake force generation target setting process shown in FIG. 2 is completed. Since this process is executed every predetermined control cycle, the EPB setting is first made in a situation that does not require urgency, and then a right turn instruction is issued or a high-speed vehicle approaches from the rear to increase urgency. When the situation changes, the EPB setting is switched to the hydraulic brake setting.

  On the other hand, when the brake force generation control process shown in FIG. 3 is executed, it is determined in step 200 whether or not the BH execution condition is satisfied. For BH, if the BH execution condition is that a BH operation switch (not shown) is pressed, the switch is turned on. If BH is executed regardless of the BH switch, for example, the brake pedal is depressed. In this case, the start condition is executed when the vehicle is stopped for a predetermined time. Further, BH is released with a release condition when, for example, the depression of the brake pedal is released and the accelerator pedal is depressed. For this reason, after satisfying the start condition, it is determined that the BH execution condition is satisfied until the release condition is satisfied.

  If the determination in step 200 is affirmative, the process proceeds to step 210 to determine whether or not the EPB is being set. This process is executed by reading the setting contents in the brake force generation target setting process described above, and determines whether the EPB is being set based on whether the EPB is set or the hydraulic brake is set. ing. If an affirmative determination is made here, the routine proceeds to step 220, where the EPB 3 is operated as a target for generating a braking force, and a braking force for maintaining the stop state of the vehicle is generated. Further, if a negative determination is made here, the routine proceeds to step 230, where various electromagnetic valves of the hydraulic brake 2 are operated as targets for generating the braking force, and the brake hydraulic pressure generated in the W / C is held when the vehicle is stopped. Thus, a braking force for maintaining the stopped state of the vehicle is generated.

  Further, when a negative determination is made in step 200 described above, the process proceeds to step 240 to release BH, that is, the operation of the hydraulic brake 2 is stopped and the braking force is released, or the electric actuator of the EPB 3 is released. To release the braking force. Thereby, for example, when the red signal changes to the green signal, the vehicle can be started smoothly. In particular, when urgency is required, since the hydraulic brake is set, it is possible to stop the operation of the hydraulic brake 2 and release the braking force with high responsiveness, and start the vehicle more smoothly. It becomes possible.

  As described above, the information on the traffic light is obtained, the predicted stop time T3 of the vehicle is calculated, and the braking force is generated using either the hydraulic brake 2 or the EPB 3 from the predicted stop time T3. It is determined whether the consumption is reduced. Thereby, in the BH control, when generating the brake force for executing the BH using both the hydraulic brake 2 and the EPB 3, it is possible to select the one that can further reduce the power consumption. Therefore, the power consumption can be further reduced.

  The predicted stop time T3 is not set to the red light duration T2, but is assumed to be the time at which the vehicle is actually stopped. Which of the hydraulic brake 2 and the EPB 3 is used depending on the presence or absence of urgency? It is set. For this reason, in the situation as described below, it is possible to accurately set which of the hydraulic brake 2 and the EPB 3 is used according to the situation.

  For example, (1) Immediately after the red signal has changed from a green signal to a red signal in a traffic light having a long red signal duration T2, or (2) it has passed for a while since the signal having a long red signal duration T2 has changed from a green signal to a red signal. If the red signal continues for a long time, EPB3 is used. Also, (3) EPB3 is used even when the signal duration of the red signal is short, even if the elapsed time after the change from the blue signal to the red signal is short and there is still some red signal time. On the other hand, (4) even if the red signal duration T2 is long, if the elapsed time after becoming a red signal is long and the time until the next blue signal changes is short, (5) stop at the red signal However, the hydraulic brake 2 is used when urgency is required, such as when turning right or when approaching a high-speed vehicle from behind. In this way, it is possible to accurately set whether to use the hydraulic brake 2 or the EPB 3 according to the situation, and when using the hydraulic brake 2 in response to an urgent need, while reducing power consumption. The braking force can be released with good performance.

  Further, since EPB3 is used when BH is executed for a long time, it is not necessary to drive the hydraulic brake 2 for a long time to perform BH, and there is a problem of pressure drop due to leakage of the solenoid valve or durability of the solenoid valve, etc. There is also an effect that it can be prevented from occurring.

(Second Embodiment)
A second embodiment of the present invention will be described. In the first embodiment, a traffic light is assumed as a vehicle stop target, and the predicted stop time T3 that is predicted to stop the vehicle is calculated using information related to the traffic light as vehicle peripheral information. The same thing can be applied to a crossing breaker.

  That is, when the vehicle is stopped by the cutoff signal of the crossing breaker, the time for which the vehicle stops changes according to the length of time until the cutoff signal stops. For this reason, in the various information input process of step 100 of FIG. 2 described above, information related to the cutoff signal is acquired as the vehicle peripheral information, and a predicted stop time T3 that is predicted to stop the vehicle is calculated based on this information.

  In the case of a crossing breaker, a time corresponding to a preset red light duration T2 is not assumed. For this reason, as information regarding the interruption signal, information such as the duration of the interruption signal or the position of the interruption device may be acquired from the interruption device or the roadside device 8, and the stop prediction time T3 may be directly calculated from the acquired information. . Even in this case, if the estimated stop time T3 is corrected based on the information indicating the state of the preceding vehicle and the distance from the stop position (that is, the stop line) of the earliest vehicle to the host vehicle, the situation is further improved. It is possible to set an appropriate stop prediction time T3 according to the above.

  Then, by performing the same processing as in the first embodiment in steps 110 and 130 to 150 in FIG. 2, the hydraulic brake 2 and the EPB 3 that are more advantageous from the viewpoint of power consumption are to be generated. Set. At this time, in the case of a crossing circuit breaker, there is no right turn instruction like a traffic light, so when setting the brake force generation target, a part other than the process of step 120 of steps 110 to 150 in FIG. 2 is executed. Will do.

  As described above, assuming a crossing breaker as a vehicle stop target, the predicted stop time T3 is calculated based on the breaker breaker signal to set which one of the hydraulic brake 2 and EPB3 is used. May be. Even if it does in this way, the effect similar to 1st Embodiment can be acquired.

(Other embodiments)
In the above embodiment, the case where various information acquired by the brake ECU 1 is obtained from the peripheral images of the navigation ECU 4, the meter ECU 6, or the in-vehicle camera 7 has been described only as an example, from other information acquisition means Various information may be acquired.

  For example, it is good also as a form which receives the information from the roadside machine 8 with the vehicle-mounted communication apparatus 5, and inputs it into brake ECU1 directly. Moreover, although the roadside unit 8 and the in-vehicle communication device 9 of another vehicle have been described as examples of information sources when acquiring various types of information from outside the vehicle, other information sources may be used. For example, information on traffic lights is stored in road information stored in the database of the navigation system, and the timing at which the green signal is changed to the red signal is measured using the peripheral image of the in-vehicle camera 7, and the red signal is obtained therefrom. By calculating the elapsed time T1 after that, the estimated stop time T3 can be obtained. Using the predicted stop time T3 obtained in this way, it may be determined which one of the hydraulic brake 2 and EPB3 is used.

  In addition, the relative distance and relative speed with respect to the vehicle ahead can be acquired using a laser radar or the like. For example, when the vehicle is stopped by a red light or a circuit breaker, if the relative distance from the preceding vehicle is long and the preceding vehicle has not yet stopped, There is a possibility of a quick relapse. In such a case, the hydraulic brake 2 may be set instead of the EPB 3. In general, the laser radar is used to detect the relationship with the vehicle ahead, but can also be used to detect the relationship with the vehicle behind. In that case, based on the relative distance and relative speed with the rear vehicle detected by the laser radar, it is determined whether or not the high-speed vehicle is approaching from behind, so that the rear vehicle cannot stop in front of the host vehicle. In the situation, the hydraulic brake 2 may be set by determining that the situation requires urgency.

  In the above embodiment, the brake hydraulic pressure generated by the W / C when the vehicle is stopped is held to generate the braking force for executing the BH by the hydraulic brake 2. The brake force may be generated by driving various electromagnetic valves and a pump driving motor provided in the pressure brake 2 to automatically increase the W / C pressure.

  The steps shown in each figure correspond to means for executing various processes. Specifically, the part of the brake ECU 1 that executes the process of step 100 is the information acquisition means, the part that executes the processes of steps 110 to 150 is the brake force generation target setting means, and the part that executes the processes of steps 120 and 130 Is the urgency determining means, and the portion for executing the processing of steps 210 to 230 corresponds to the braking force generating means.

  DESCRIPTION OF SYMBOLS 1 ... Brake ECU, 2 ... Hydraulic brake, 3 ... EPB, 4 ... Navigation ECU, 5 ... In-vehicle communication device, 6 ... Meter ECU, 7 ... In-vehicle camera, 8 ... Roadside device, 9 ... In-vehicle communication device

Claims (7)

The hydraulic brake (2) and the electric parking brake (3) are controlled, and when the vehicle stops and satisfies a predetermined condition, the hydraulic brake (2) or the electric parking brake (3) is used to brake A brake control device for a vehicle that generates a force and executes a brake hold control for maintaining the stop state of the vehicle,
Information acquisition means (100) for acquiring surrounding information of the vehicle;
If the estimated stop time (T3) where the vehicle is predicted to stop is calculated from the surrounding information acquired by the information acquisition means (100) and the predicted stop predicted time (T3) is greater than a preset threshold value. Brake force generation target setting means (110 to 150) that sets the electric parking brake (3) as a target for generating a braking force when the vehicle is kept stopped, and sets the hydraulic brake (2) if it is small. )When,
A brake force is generated by operating either the hydraulic brake (2) or the electric parking brake (3) according to the setting contents of the brake force generation target setting means (110 to 150), and the vehicle And a brake force generating means (210-230) for maintaining the stopped state of the vehicle. The information acquisition means (100) acquires information on traffic lights at intersections where vehicles stop as the surrounding information,
The braking force generation target setting means (110 to 150) is configured to predict the stop time (predicted to stop the vehicle at the intersection by a red signal of the traffic light from the information on the traffic light acquired by the information acquisition means (100). The vehicle brake control device according to claim 1, wherein T3) is calculated. The information acquisition means (100) acquires information on a crossing breaker at which a vehicle stops as the surrounding information,
The brake force generation target setting means (110, 130 to 150) is predicted to stop the vehicle at the level crossing by a shutoff signal of the breaker based on information about the breaker acquired by the information acquisition means (100). The vehicle brake control device according to claim 1, wherein a predicted stop time (T3) is calculated.   The brake force generation target setting means (110 to 150) includes urgency determination means (120, 130) for determining whether or not the vehicle is in a situation that requires urgency to quickly shift from a stopped state to a start state. Even when the estimated stop time (T3) is greater than the threshold, when the emergency determination means (120, 130) determines that the situation requires urgency, the vehicle is kept in a stopped state. The vehicular brake control device according to any one of claims 1 to 3, wherein the hydraulic brake (2) is set as a target for generating the braking force. The information acquisition means (100) acquires information on a direction indicator,
The urgency determining means (120) is characterized in that when the right turn instruction is issued based on the information related to the direction indicator acquired by the information acquisition means (100), it is determined that the situation requires the urgency. The vehicle brake control device according to claim 4. The information acquisition means (100) acquires information about the rear vehicle,
The urgency determining means (130) determines that the urgency is required when a high-speed vehicle is approaching from behind based on the information on the rear vehicle acquired by the information acquisition means (100). The vehicle brake control device according to claim 4 or 5. The information acquisition means (100) acquires information about the preceding vehicle,
The brake force generation target setting means (110 to 150) is configured to determine the number of the preceding vehicles and the stop position of the earliest vehicle based on the information about the preceding vehicle acquired by the information acquiring means (100) and the surrounding information. The vehicle brake control device according to any one of claims 1 to 6, wherein the estimated stop time (T3) is corrected according to a distance from the vehicle to the host vehicle.

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