JP5939071B2 - Automatic braking device - Google Patents

Description

  The present invention relates to an automatic braking device that detects a front obstacle and automatically applies a braking force to a host vehicle.

  2. Description of the Related Art Conventionally, an automatic braking device that detects a front obstacle by outputting a millimeter wave, infrared wave, or other radar wave toward the front of the vehicle and automatically activates the braking device to apply a braking force to the vehicle is known. (For example, Patent Document 1). This type of automatic braking device includes a braking determination sensor including the radar wave transceiver, and the braking determination sensor detects an obstacle and satisfies predetermined braking requirements (distance to the obstacle, etc.). When it is determined that the brake device is being operated, a brake request signal is output to operate the brake device.

  Since the automatic braking device is a facility for avoiding a collision with a front obstacle, the automatic braking device is not normally operated while the vehicle is moving backward. Therefore, conventionally, a wheel speed sensor capable of detecting forward / backward is mounted on a vehicle, and a braking request signal is only generated when a forward obstacle is detected during forward movement of the vehicle based on an output signal from the wheel speed sensor. If a braking request signal is output from the braking determination sensor while the vehicle is moving backward, it is considered that the automatic braking device is abnormal (failure of the braking determination sensor, etc.), and a warning lamp is activated. A warning is issued.

JP-A-5-310119

  In recent years, a higher level of safety has been demanded of vehicles, and the automatic braking device capable of avoiding a collision with a front obstacle is a useful facility that contributes to the suppression of the occurrence of an accident. However, since the automatic braking device is a relatively expensive facility, the number of installed vehicles (grade) is often limited or it is often treated as an option.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an automatic braking device with a simpler configuration and at a lower cost.

  In order to solve the above-described problem, the applicant replaces the forward / reverse determination by the wheel speed sensor (the wheel speed sensor capable of detecting forward / reverse), and instead of determining the forward / reverse of the vehicle based on the position (shift position) of the shift lever. I thought about judging the retreat. According to this configuration, it is possible to operate the automatic braking device while detecting the forward / backward movement of the vehicle with a simple configuration without using a complicated and expensive wheel speed sensor. Therefore, it is possible to provide an automatic braking device at a lower cost than in the past.

  However, since the shift lever can be switched to the reverse position even when the vehicle is moving forward, there is one problem here. That is, as will be described in detail later in “Mode for Carrying Out the Invention”, the brake determination sensor during forward movement of the vehicle (a state in which the shift lever is positioned at the drive position), for example, when the vehicle is turned over near the parking lot wall. When the vehicle detects an obstacle (wall), a braking request signal is output from the braking determination sensor. Thereafter, when the shift lever is switched to the reverse position for turning the vehicle before the vehicle stops, the vehicle Although the vehicle is still moving forward, the shift lever is positioned at the reverse position, so that it is determined that the vehicle is moving backward on the automatic braking system (automatic braking device). That is, since the vehicle is actually moving forward, the system is functioning normally, but it is determined that the system is abnormal, and as a result, an unnecessary alarm is issued. Such an unnecessary alarm gives the driver anxiety about the automatic braking device and forces unnecessary maintenance. Therefore, it is essential to improve this point.

Such a problem is solved by the following present invention. That is, the present invention is an automatic braking device that detects a front obstacle and applies a braking force to the vehicle, a detection unit that detects a front obstacle, and a braking force application unit that applies a braking force to the vehicle. Determining whether or not braking is necessary when an obstacle is detected by the detecting means, and outputting a braking request signal when necessary, and applying braking force to the vehicle based on the input of the braking request signal. The braking control means for controlling the braking force applying means to apply, the shift position detecting means for detecting the position of the shift lever of the vehicle, and the shift position detecting means detecting that the shift lever is in the reverse position. and when the state in which the braking request signal from the braking determination means is output is generated, comprising abnormality detecting means for detecting the state as an abnormal, wherein the abnormality detecting means Trevor detects only before serial state when the braking request signal is output after being switched to the Reverse position as the abnormality, the braking request signal is output before the shift lever is switched to Reverse position If it has is to ignore without detecting the pre SL state as abnormal.

  In this automatic braking device, when the abnormality detection means outputs a braking request signal from the braking determination means in a state where the shift lever is in the reverse position based on the detection of the shift position by the shift position detection means, this state is set. Detect as an abnormal condition. That is, the abnormality detection means detects the abnormal state by determining whether the vehicle is moving forward or backward based on the detection of the shift position by the shift position detection means. According to such a configuration, it is possible to provide the automatic braking device with a simple configuration and at a low cost, as compared with the conventional device that determines whether the vehicle is moving forward or backward by the wheel speed sensor.

Moreover, the abnormality detecting means, said only when the shift lever is the braking request signal is output after being switched to the Reverse position to detect abnormal, the braking request before the shift lever is switched to the reverse position when the signal is output is ignored without detecting the pre SL state as abnormal. Therefore, the inconvenience as described above, that is, the brake request signal is output during the forward movement of the vehicle (the stage where the shift lever is in the drive position), and then the shift lever is switched to the reverse position before the vehicle stops, braking demand signal from the braking determination means despite being output normally, the automatic braking system it becomes possible to prevent that are abnormal.

Incidentally, in the automatic braking system, the abnormality detecting means, which said shift lever is detected on the SL state as abnormal when it is detected over a predetermined time by said shift position detecting means to be located to the reverse position It may be.

  According to this configuration, after the braking request signal is output from the braking determination unit, the shift lever is temporarily positioned at the reverse position while the driver stops the vehicle and switches the shift lever from the drive position to the parking position. It is possible to more reliably prevent the abnormal state from being detected due to this.

  As described above, according to the present invention, the automatic braking device can be provided with a simpler configuration and at a lower cost.

It is a block diagram which shows the automatic braking device of this invention. It is a flowchart which shows the control action of the system abnormality detection by a braking control unit. (A), (b) is a timing chart which shows the output signal of a shift position sensor and a braking determination unit. It is a schematic diagram explaining the problem of the vehicle turnback and system abnormality detection at the wall. It is a plane schematic diagram which shows the position of a shift indicator and a shift lever.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing an embodiment of an automatic braking device according to the present invention. This automatic braking device is for detecting a front obstacle and automatically applying a braking force to the host vehicle.

  As shown in the figure, the automatic braking device includes a braking determination unit 10, a braking control unit 12, a braking device 14, an alarm device 16, and various sensors. The various sensors detect a shift position sensor 20 that detects the shift position of the shift lever, a vehicle speed sensor 22 that detects the traveling speed of the host vehicle, a steering angle sensor 24 that detects the steering angle of the steering wheel, and a displacement amount of the accelerator pedal. An accelerator opening sensor 26 is included, and these sensors 20 to 26 are connected to the braking determination unit 10.

  The braking determination unit 10 detects an obstacle ahead of the vehicle and determines whether or not to apply a braking force to the host vehicle, and includes a braking determination unit 11a and an obstacle detection unit 11b.

  The obstacle detection unit 11b (corresponding to the detection means of the present invention) is not shown in detail, but a transmitter that transmits an infrared laser wave (detection wave) for obstacle detection toward the front of the vehicle, and the vehicle A receiver that receives a reflected wave of a detection wave reflected by an obstacle ahead, and a distance or relative distance between the vehicle and the obstacle by sequentially measuring the time from the detection wave transmission time to the reflected wave reception time. And a processing device that calculates a speed and outputs a detection signal to the braking determination unit 11a. In this example, the detection wave for detecting the obstacle is an infrared laser wave, but it may be a millimeter wave or an ultrasonic wave.

The braking determination unit 11a (corresponding to the braking determination unit of the present invention) determines whether or not to apply a braking force to the host vehicle based on the input of a detection signal from the obstacle detection unit 11b, that is, the obstacle detection unit 11b. It is determined whether or not the detection result (the distance between the host vehicle and the obstacle, the relative speed, etc.) satisfies a predetermined braking condition, and a braking request signal is output to the braking control unit 12 when it is determined that the detected condition is satisfied. To do. Note that a detection signal of the shift position sensor 20 (corresponding to the shift position detection means of the present invention) is input to the brake determination unit 11a, and the brake determination unit 11a has a vehicle shift position such as a drive position. The brake request signal is output only when the vehicle is in the forward position (“D”, “1”, “2”, etc.) and the braking condition is satisfied. Thereby, in this automatic braking device, automatic braking is performed only when the vehicle moves forward.

  Although not shown in detail, the shift position sensor 20 includes, for example, a slider that slides in response to shift position selection, a movable sensor that moves integrally with the slider, a housing that supports the slider, and the housing A shift sensor is detected based on a relative position between the movable sensor and the fixed sensor, and a detection signal is output to the brake determination unit 11a.

The brake control unit 12 (corresponding to the brake control means and the abnormality detection means of the present invention) controls the brake device 14, and controls the host vehicle according to the input of a brake request signal from the brake determination unit 11a. A control signal is output to the brake device 14 to give power. The brake device 14 receives the control signal and supplies the hydraulic pressure to the driving means such as a wheel cylinder to give a braking force to the vehicle.

The braking control unit 12 determines whether or not the input of the braking request signal from the braking determination unit 11a is normal, that is, whether or not the automatic braking system (automatic braking device) is normal, specifically the braking determination unit 11a and the like. If the automatic braking system is not normal (abnormal), a control signal is output to activate the alarm device 16 such as a warning light or a check light. To inform the driver.

More specifically, the brake control unit 12 receives the detection signal of the shift position sensor 20, the vehicle shift position is in the reverse position ("R"), and the brake request signal is input. If so, the braking control unit 12 outputs a control signal to the alarm device 16 to activate the alarm device 16. In other words, as described above, the automatic braking device originally performs automatic braking only when the vehicle moves forward, so that the braking determination unit 11a determines that the vehicle shift position is in the reverse position ("R"). When the braking request signal is input, it is considered that the automatic braking system is abnormal. Therefore, in this case, the alarm device 16 is activated to notify the driver.

  Here, the abnormality detection control of the automatic braking system by the braking control unit 12 will be described in detail with reference to the flowchart of FIG.

  In step S1, the braking control unit 12 first determines whether or not a braking request signal has been input. If it is determined that the braking request signal is input (YES in step S1), the braking control unit 12 proceeds to step S3 and determines whether or not the vehicle is moving backward. Specifically, based on the detection signal from the shift position sensor 20, it is determined whether or not the shift lever is positioned at the reverse position.

  If it is determined that the vehicle is moving backward (the shift lever is located at the reverse position) (YES in step S3), the brake control unit 12 further determines the timing when the shift lever is switched to the reverse position and the braking determination. The timing of switching to the reverse position of the shift lever is compared with the input timing of the braking request signal from the section 11a, and it is determined whether or not the switching timing of the shift lever to the reverse position is before the input of the braking request signal.

  Here, if it is determined that the timing for switching the shift lever to the reverse position is before the input of the braking request signal (YES in step S5), the braking control unit 12 sets the current state of the automatic braking system. After determining that there is an abnormality and operating the alarm device 16 (step S7), this flowchart is terminated. On the other hand, if it is determined that the timing for switching the shift lever to the reverse position is later than the input of the braking request signal (NO in step S5), the automatic braking system is determined to be normal, and the alarm device 16 is activated. This flowchart is finished without being operated.

That is, when the shift position of the vehicle is located in the reverse position and the braking request signal is input, brake control unit 12, a braking request signal is output after the shift lever is switched to the Reverse position If only (see FIG. 3 (a)), to detect the state as abnormality of the automatic braking system actuates the alarm device 16, a braking request signal before the shift lever is switched to reverse position is outputted In the case (see FIG. 3B), the above state is ignored without being detected as an abnormality in the automatic braking system.

  It should be noted that the state where the vehicle shift position is at the reverse position and the braking request signal is input is not uniformly abnormal in the automatic braking system, and an exception (NO in step S5) is provided as described above. The reason is as follows.

  That is, in the braking control unit 12 that detects an abnormality of the automatic braking system based on the detection of the shift position by the shift position sensor 20, the state where the shift position is in the reverse position and the braking request signal is input is uniformly set. When the alarm device 16 is operated as an abnormal state of the automatic braking system, there are the following disadvantages. For example, when the vehicle is turned around near the wall of the parking lot, specifically, as shown in FIG. 4, the vehicle 32 is advanced toward the wall 30, and the vehicle 32 is stopped and moved backward at the wall. When the direction is switched, it is conceivable that the obstacle detection unit 11b detects the wall 30 while the vehicle 32 is moving forward, and a braking request is output from the braking determination unit 11a. In this case, if the shift lever is switched to the reverse position (symbol Q in the figure) after the braking request signal is output (symbol P in the figure) and before the vehicle 32 is stopped (symbol Q in the figure), the vehicle is still moving forward and the braking determination is made. Although the output of the braking request signal from the unit 11a is normal, the braking request signal is erroneously output on the automatic braking system (automatic braking device) because the shift lever is positioned at the reverse position. As a result, the alarm device 16 is activated. In such a case, the alarm device 16 is activated even though there is no abnormality in the automatic braking system, so that the driver feels uneasy and is forced to perform unnecessary maintenance. As another case, the obstacle detection unit 11b detects the wall 30 while the vehicle 32 is moving forward, and after the braking determination signal is output from the braking determination unit 11a, the driver stops the vehicle 32 near the wall. It is conceivable to get off and check the safety of the vehicle. In such a case, the process of switching the shift lever 34 from the drive position (“D”) to the parking position (“P”) as shown in FIG. 5 during the output of the brake request signal from the brake determination unit 11a. Thus, when the shift lever 34 is temporarily positioned at the reverse position, the shift lever 34 is positioned at the reverse position and the braking request signal is input. It is conceivable that the alarm device 16 operates even though there is no abnormality.

Therefore, in the brake control unit 12, the shift position of the vehicle is located in the reverse position, and even if the braking request signal is input, the braking request before the shift lever is switched to Reverse position If the signal is output, ignoring without detecting the above state as abnormality of the automatic braking system (NO in step S5 of FIG. 2), a braking request signal after the shift lever is switched to the reverse position Is output (when YES in step S5 of FIG. 2), the above state is detected as an abnormality in the automatic braking system, and the alarm device 16 is activated. According to such a configuration of the brake control unit 12, as shown in FIG. 4, after the brake request signal is output (reference symbol P in the figure), the shift lever is switched to the reverse position before the vehicle 32 stops. (Reference sign Q in the figure), the alarm device 16 is prevented from operating. Similarly, after the braking request signal is output from the braking determination unit 11a, the driver stops the vehicle 32 and switches the shift lever 34 from the drive position (“D”) to the parking position (“P”). The alarm device 16 is prevented from operating. Therefore, it is possible to avoid the inconvenience that the driver feels unnecessary anxiety and is forced to perform unnecessary maintenance.

  As described above, in the automatic braking device of the present invention, when the braking request signal is input from the braking determination unit 11a with the shift lever positioned at the reverse position based on the detection of the shift position by the shift position sensor 20. The braking control unit 12 is configured to detect this state as an abnormal state. In other words, the braking control unit 12 determines the forward / reverse of the vehicle based on the detection of the shift position by the shift position sensor 20, and detects the abnormal state. According to such a configuration, the automatic braking device has a simple configuration as compared with the conventional automatic control device of this type that uses a relatively complicated and expensive wheel speed sensor to determine whether the vehicle is moving forward or backward. And at a low cost.

Moreover, the brake control unit 12, the shift lever is detected the abnormal state only when a braking request signal is output from the brake judging unit 11a after being switched to the Reverse position is switched shift lever is in the reverse position If a braking request signal has been output from the braking determination unit 11a before, the abnormal state is ignored without being detected. Therefore, the disadvantage caused by applying the shift position sensor 20, that is, as described above, the alarm device 16 is activated by the shift lever switching timing although the automatic braking system is normally normal. Can be resolved.

  Therefore, according to the above-described automatic braking device, it is possible to provide the automatic braking device with a simpler configuration and at a lower cost while appropriately maintaining functions equivalent to those of this type of conventional automatic braking device.

  The automatic braking device described above is an exemplification of a preferred embodiment of the automatic braking device according to the present invention, and its specific configuration can be appropriately changed without departing from the gist of the present invention.

  For example, in the above embodiment, the brake control unit 12 controls the brake device 14 and is configured to detect the abnormal state based on an output signal from the shift position sensor 20. That is, the brake control unit 12 has a function as an abnormality detection unit in addition to a function as a brake control unit of the present invention. Of course, an output signal from the shift position sensor 20 is provided separately from the brake control unit 12. Independent abnormality detecting means for detecting the abnormal state based on the above may be provided.

  Although not mentioned in the above embodiment, the braking control unit 12 detects the abnormal state when the shift position sensor 20 detects that the shift lever is in the reverse position for a predetermined time or more. It may be configured. According to this configuration, as described above, in the process in which the driver stops the vehicle 32 and switches the shift lever 34 from the drive position to the parking position after the braking request signal is output from the braking determination unit 11a. It is possible to prevent the alarm device 16 from operating due to the fact that 34 is temporarily located at the reverse position.

DESCRIPTION OF SYMBOLS 10 Brake determination unit 11a Brake determination part 11b Obstacle detection part 12 Brake control unit 14 Brake device 16 Alarm device 30 Wall 32 Vehicle

Claims (2)

An automatic braking device that detects a front obstacle and applies a braking force to the vehicle,
Detection means for detecting obstacles ahead;
Braking force applying means for applying braking force to the vehicle;
Braking determination means for determining whether or not braking is required when an obstacle is detected by the detection means, and outputting a braking request signal when necessary;
Braking control means for controlling the braking force applying means to apply a braking force to the vehicle based on the input of the braking request signal;
Shift position detecting means for detecting the position of the shift lever of the vehicle;
When the state in which the shift lever is the braking request signal is output from the detected and the brake judging means by said shift position detecting means to be located in the reverse position is generated, detects this state as a abnormal An abnormality detecting means for
The abnormality detecting means, the shift lever is detected only before serial state when the braking request signal is output after being switched to the Reverse position as abnormal, before the shift lever is switched to Reverse position when said braking request signal is output is ignored without detecting the pre SL state as abnormal, that the automatic braking device according to claim. The automatic braking device according to claim 1,
The abnormality detection means, an automatic control device, wherein the shift lever is detected on the SL state as abnormal when it is detected over a predetermined time by said shift position detecting means that is located in the reverse position.

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