JP2020157960A - Emergency braking system, emergency braking method and emergency braking program - Google Patents

Abstract

To properly brake a vehicle in the event of an abnormity of a driver.SOLUTION: An emergency braking system 10 for a vehicle provided with a main brake 5 for applying braking force to wheels and an auxiliary brake 6 for assisting the main brake 5 includes a determination unit 7A and a braking unit 7B. The determination unit 7A determines whether braking of the vehicle is necessary or not at least one of passively or automatically when an abnormality occurs on a driver. The braking unit 7B prohibits an action of the auxiliary brake 6 and controls the main brake 5 to apply a prescribed braking force to the wheels when it is determined that braking is necessary by the determination unit 7A.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to systems, methods and programs that automatically brake the vehicle in the event of a driver malfunction.

Conventionally, when an abnormal situation such as fainting of a driver occurs, a system (Emergency Driving and Stop System) that automatically brakes (decelerates) the vehicle in response to a button operation or a switch operation and then stops the vehicle (EDSS; Emergency Driving and Stop System) has been used. Are known. For example, in Patent Document 1, when an abnormality of the driver is detected and a button installed in the vehicle is pressed by a passenger, it is determined that the vehicle needs to be stopped urgently, and an automatic brake is applied. The technology used is described.

Japanese Unexamined Patent Publication No. 2011-57134

As described above, when the vehicle is automatically braked when the driver is abnormal, a predetermined braking force is applied to the wheels by the main brake. From the viewpoint of safety, this braking force needs to be set in advance so that the deceleration of the vehicle does not exceed a predetermined value (for example, 0.25 G). However, the deceleration of the vehicle varies due to the action of the auxiliary brake even if the magnitude of the braking force applied to the wheels is constant. Specifically, in the state where the auxiliary brake is applied, the deceleration becomes larger than in the state where the auxiliary brake is not applied. For this reason, if the braking force applied to the wheels is set based on the state in which the auxiliary brake is operating, it is possible that appropriate deceleration cannot be obtained in situations where it is difficult for the vehicle to decelerate, such as when descending a slope. There is.

This disclosure was devised in view of the above-mentioned problems, and one of the purposes of the present disclosure is to brake the vehicle more appropriately in the event of a driver abnormality.

The present disclosure has been made to solve at least a part of the above-mentioned problems, and can be realized as the following aspects or application examples.
(1) The emergency braking system according to this application example is an emergency braking system for a vehicle provided with a main brake that applies a braking force to the wheels and an auxiliary brake that assists the main brake, and an abnormality has occurred in the driver. At that time, a determination unit that determines the necessity of braking the vehicle at least in both passive and automatic manners, and when the determination unit determines that the braking is necessary, the action of the auxiliary brake is prohibited and the operation of the auxiliary brake is prohibited. It is provided with a braking portion that controls the main brake and applies a predetermined braking force to the wheels. As a result, when an abnormality occurs in the driver and the vehicle needs to be braked, the action of the auxiliary brake is eliminated (disabled), and the vehicle is braked (decelerated) by the action of the main brake. Therefore, the variation in deceleration of the vehicle can be suppressed.

(2) The emergency braking system according to the present application example includes a control unit that controls the auxiliary brake in response to an operation by the driver, and the braking unit is when the determination unit determines that the braking is necessary. , The emergency stop signal may be transmitted to the control unit, and when the control unit receives the emergency stop signal, the auxiliary brake may be controlled to the non-operating state by ignoring the operation. In this case, the operation of the auxiliary brake is prohibited only by transmitting an emergency stop signal when the driver is abnormal, so that it is not necessary to change the mechanical structure.

(3) In the emergency braking system according to the present application example, the vehicle is provided with an engine as a drive source and a connection / disconnection mechanism for connecting / disconnecting power transmission from the engine to the wheels, and the auxiliary brake is provided. However, the absorbed horsepower of the engine may be increased according to the operation by the driver. Further, the emergency braking system according to the present application example includes a control device for controlling the disconnection mechanism, and the braking unit gives an emergency stop signal to the control device when the determination unit determines that the braking is necessary. When the control device receives the emergency stop signal, the control device may control the disconnection mechanism to cut off the transmission of the power. In this case, when the driver is abnormal, the transmission of power from the engine to the wheels is mechanically cut off, so that the absorbed horsepower (braking force) of the engine does not act on the wheels. Therefore, the variation in deceleration of the vehicle can be further suppressed.

(4) In the emergency braking system according to the present application example, the vehicle is provided with a transmission that includes the disconnection mechanism and is in a neutral state with the disconnection mechanism blocking the transmission of power. The control device has a shift control unit that controls the transmission in response to an operation on the gear shift selector by the driver, and the shift control unit operates the gear shift selector when the emergency stop signal is received. May be ignored and the transmission may be controlled to the neutral state. In this case, since the action of the auxiliary brake is prohibited by using the disconnection mechanism included in the existing transmission, the increase in the device cost can be suppressed.

(5) The emergency braking method according to this application example is an emergency braking method for a vehicle provided with a main brake that applies a braking force to the wheels and an auxiliary brake that assists the main brake, and an abnormality has occurred in the driver. At the time, the determination step of determining the necessity of braking of the vehicle at least one of passive and automatic, and when the determination step determines that the braking is necessary, the action of the auxiliary brake is prohibited, and the above-mentioned It includes a braking step of controlling the main brake to apply the predetermined braking force to the wheels. As a result, when an abnormality occurs in the driver and the vehicle needs to be braked, the action of the auxiliary brake is eliminated (disabled), and the vehicle is braked (decelerated) by the action of the main brake. Therefore, the variation in deceleration of the vehicle can be suppressed.

(6) In the emergency braking method according to the present application example, the braking step includes a transmission step of transmitting an emergency stop signal to a control unit that controls the auxiliary brake in response to an operation by the driver, and the emergency braking. The method may include a control step of ignoring the operation and controlling the auxiliary brake to a non-operating state after performing the transmission step. In this case, the operation of the auxiliary brake is prohibited only by transmitting an emergency stop signal when the driver is abnormal, so that it is not necessary to change the mechanical structure.

(7) In the emergency braking method according to the present application example, the vehicle is provided with an engine as a drive source and a connection / disconnection mechanism for connecting / disconnecting power transmission from the engine to the wheels, and the auxiliary brake is provided. However, the absorption horsepower of the engine is increased in response to the operation by the driver, and the braking step includes a transmission step of transmitting an emergency stop signal to a control device that controls the disconnection mechanism. Good. Further, the emergency braking method according to the present application example may include a control step of controlling the disconnection mechanism to cut off the transmission of the power after the execution of the transmission step. In this case, when the driver is abnormal, the transmission of power from the engine to the wheels is mechanically cut off, so that the absorbed horsepower (braking force) of the engine does not act on the wheels. Therefore, the variation in deceleration of the vehicle can be further suppressed.

(8) In the emergency braking method according to the present application example, the vehicle is provided with a transmission that includes the disconnection mechanism and is in a neutral state with the disconnection mechanism blocking the transmission of power. In the control step, the transmission may be controlled to the neutral state by ignoring the operation of the driver on the gear shift selector. In this case, since the action of the auxiliary brake is prohibited by using the disconnection mechanism included in the existing transmission, the increase in the device cost can be suppressed.

(9) The emergency braking program related to this application example is an emergency braking program for a vehicle provided with a main brake that applies a braking force to the wheels and an auxiliary brake that assists the main brake, and an abnormality has occurred in the driver. At the time, the determination step of determining the necessity of braking of the vehicle at least one of passive and automatic, and when the determination step determines that the braking is necessary, the action of the auxiliary brake is prohibited, and the above-mentioned A braking step of controlling the main brake to apply the predetermined braking force to the wheels is performed by the computer. As a result, when an abnormality occurs in the driver and the vehicle needs to be braked, the action of the auxiliary brake is eliminated (disabled), and the vehicle is braked (decelerated) by the action of the main brake. Therefore, the variation in deceleration of the vehicle can be suppressed.

According to the present disclosure, the vehicle can be braked more appropriately when the driver is abnormal.

It is the schematic which shows the structure of the vehicle to which the emergency braking system as an embodiment is applied. It is a block diagram which shows the structure of the emergency braking system as 1st Embodiment. It is a schematic diagram which shows the structure of the main brake mounted on the vehicle of FIG. It is a flowchart which illustrates the procedure of the process performed in the emergency ECU of the emergency braking system of FIG. It is a flowchart which illustrates the procedure of the process performed in the engine ECU of the emergency braking system of FIG. It is a block diagram which shows the structure of the emergency braking system as a 2nd Embodiment. It is a flowchart which illustrates the procedure of the process performed in the emergency ECU of the emergency braking system of FIG. It is a flowchart which illustrates the procedure of the process performed in the transmission ECU of the emergency braking system of FIG.

An emergency braking system, an emergency braking method, and an emergency braking program (hereinafter, simply referred to as "braking system", "braking method", and "braking program") as embodiments will be described with reference to the drawings. The embodiments shown below are merely examples, and there is no intention of excluding the application of various modifications and techniques not specified in the following embodiments. Each configuration of the following embodiments can be variously modified and implemented without departing from the gist thereof. In addition, it can be selected as needed, or can be combined as appropriate.

[1. First Embodiment]
[1-1. overall structure]
The braking system, braking method, and braking program according to the first embodiment automatically brake (decelerate) the vehicle 1 regardless of the manual driving operation by the driver when an abnormality occurs in the driver of the vehicle 1 shown in FIG. ) And then stopped. Here, a case where the vehicle 1 is a route bus capable of transporting a plurality of passengers will be illustrated.

The vehicle 1 is provided with an engine 2 as a drive source and a transmission 3 for changing the rotation output from the engine 2 to a rotation according to a predetermined gear ratio. The engine 2 is an internal combustion engine that uses gasoline or light oil as fuel, and its operating state is controlled by an engine ECU 8 (see FIG. 2) described later.

The transmission 3 is an automatic transmission having a function of automatically changing the gear ratio according to the traveling state of the vehicle 1, a load request, etc., and its operation is controlled by the transmission ECU 9 (see FIG. 2) described later. Will be done. In the present embodiment, a torque converter 4 is interposed between the engine 2 and the transmission 3, and the rotation output from the engine 2 is transmitted to the transmission 3 via the torque converter 4. Further, the rotation output from the transmission 3 is transmitted to the left and right drive shafts 13 via the propeller shaft 11 and the final reduction gear 12, and is transmitted from each drive shaft 13 to the wheels 14. Note that, in FIG. 1, among the wheels 14 provided in the vehicle 1, only the two wheels 14 connected to the drive shaft 13 are shown, and the other wheels 14 are omitted.

The transmission 3 includes a disconnection / disconnection mechanism 3A for putting the transmission 3 in a neutral state. The disconnection mechanism 3A is provided on the power transmission path between the engine 2 and the wheels 14, and disconnects and disconnects the power transmission from the engine 2 to the wheels 14. When the disconnection mechanism 3A cuts off the transmission of power from the engine 2 to the wheels 14, the transmission 3 is in the neutral state. When the transmission 3 is not in the neutral state, the power of the engine 2 is transmitted to the wheels 14, so that the vehicle 1 is driven. On the other hand, when the transmission 3 is in the neutral state, the power of the engine 2 is not transmitted to the wheels 14, so that the vehicle 1 is not driven.

As shown in FIG. 2, the vehicle 1 is provided with a main brake 5 that applies a braking force to the wheels 14 and an auxiliary brake 6 that assists the main brake 5 as a device for braking the vehicle 1. Further, in the vehicle 1 of the present embodiment, the auxiliary brake lever 15 operated by the driver to switch the operating state of the auxiliary brake 6 and the driver operate to change the gear stage (shift position) of the transmission 3. A gear shift selector 18 and an emergency stop button 16 that are pressed by the driver or passengers (hereinafter, the driver and passengers are collectively referred to as "passengers") when an abnormality occurs in the driver are provided.

In the present embodiment, as the main brake 5, an air brake controlled by the pressure of compressed air (hereinafter referred to as “air pressure”) is illustrated. As shown in FIG. 3, the main brake 5 includes an air tank 51 for storing compressed air, a braking mechanism 52 provided on each wheel 14 and composed of, for example, a drum brake, and an air tank 51 extending from the air tank 51 to the braking mechanism 52 for compression. It has an air pipe 53 that serves as an air passage.

The main brake 5 is configured such that the air pressure supplied from the air tank 51 to the air pipe 53 changes according to the amount of depression of the brake pedal 17. Therefore, the main brake 5 basically applies a braking force to each wheel 14 in response to a driver stepping on the brake pedal 17 (except during the emergency control described later). Hereinafter, with respect to the air pipe 53, the air tank 51 side is the upstream side and the braking mechanism 52 side is the downstream side based on the flow direction of the compressed air. A control valve for ABS (Antilock Brake System), a switch that switches on and off according to the air pressure, and the like (both not shown) are located downstream of the double check valve 58 of the air pipe 53, which will be described later. It may be provided.

The main brake 5 of the present embodiment has two other air pipes 55 connected to the air pipe 53 so as to bypass the brake pedal 17, and a pressure reducing valve 56 and a solenoid valve 57 provided in the air pipe 55. It also has a double check valve 58 provided at the connection portion of the air pipes 53 and 55. The air pipe 55 connects the upstream side and the downstream side of the brake pedal 17 of the air pipe 53 described above, and serves as a passage for compressed air. Hereinafter, with respect to the air pipe 55, the air tank 51 side is the upstream side and the double check valve 58 side is the downstream side based on the flow direction of the compressed air.

The pressure reducing valve 56 (reducing valve) reduces the air pressure supplied from the air tank 51 to a preset value (hereinafter referred to as "set pressure"), and is provided immediately downstream of the air tank 51. The solenoid valve 57 opens and closes a passage in the air pipe 55 (allows or prohibits the flow of compressed air in the air pipe 55), and is provided downstream of the pressure reducing valve 56.

Hereinafter, regarding the solenoid valve 57, a state in which the passage in the air pipe 55 is closed (the flow of compressed air in the air pipe 55 is prohibited) is referred to as an “off state”, and the passage in the air pipe 55 is opened (air pipe). The state (allowing the flow of compressed air in 55) is referred to as an "on state". The solenoid valve 57 is turned off by default. The on / off state of the solenoid valve 57 is controlled by the emergency ECU 7 (see FIG. 2).

As shown in FIG. 3, the double check valve 58 allows the higher air pressure of the air pressure supplied from the brake pedal 17 and the air pressure supplied from the solenoid valve 57 to flow to the braking mechanism 52. is there.

The main brake 5 of the present embodiment is not provided with an electronic control system that variably controls the braking force applied to the wheels 14. Therefore, when the solenoid valve 57 is in the ON state and the air pressure from the solenoid valve 57 is supplied to the braking mechanism 52 through the double check valve 58, the air pressure supplied to each braking mechanism 52 is the pressure reducing valve 56. It becomes a constant value according to the set pressure of. Therefore, when the solenoid valve 57 is in the ON state, the magnitude of the braking force applied to the wheels 14 by the air pressure supplied from the air pipe 55 is constant.

Although one braking mechanism 52 is shown in FIG. 3, a plurality of braking mechanisms 52 may be connected to the air pipe 53. Further, a plurality of air pipes 53 and 55 and various valves 56 to 58 may be provided (for example, for each of the front portion and the rear portion of the vehicle 1). Further, the air tank 51 may be used in combination with another device (for example, an air suspension) mounted on the vehicle 1.

As shown in FIG. 2, the auxiliary brake 6 brakes the vehicle 1 by a mechanism different from that of the main brake 5, and is, for example, an exhaust brake, a compression release brake (power tard brake), or a retarder. The auxiliary brake 6 of the present embodiment is an exhaust brake that increases the absorbed horsepower (braking force, engine brake) of the engine 2 by closing a valve (not shown) provided in the exhaust pipe of the engine 2. .. The operating state of the auxiliary brake 6 (specifically, the opening degree of the valve described above) is controlled by the engine ECU 8. The auxiliary brake 6 is not limited to the exhaust brake, and may be configured by combining a plurality of the exhaust brake, the compression release brake, and the retarder, for example.

The auxiliary brake lever 15 is provided, for example, in the vicinity of the steering wheel (not shown) so that the driver can operate it. A plurality of operating positions are prepared for the auxiliary brake lever 15, and one of these operating positions is selected by the driver. The operating position of the auxiliary brake lever 15 selected by the driver is transmitted to the engine ECU 8. The auxiliary brake lever 15 may be provided with two operation positions of on and off, and may be configured to be able to switch only on (actuated) and off (non-operated) of the auxiliary brake 6. The above operation positions may be prepared, and in addition to the on / off of the auxiliary brake 6, the strength in the on state (braking force by the auxiliary brake 6) may be switched in multiple stages.

The gear shift selector 18 is provided, for example, next to the driver's seat so that the driver can operate it. The gear shift selector 18 is provided with a plurality of operating positions (for example, P range, D range, N range, and R range), and one of these operating positions is selected by the driver. The operating position of the gear shift selector 18 selected by the driver is transmitted to the transmission ECU 9.

The emergency stop button 16 is provided in, for example, the driver's seat and the passenger's seat immediately after the driver's seat so that both the driver and the passenger can operate the emergency stop button 16. The emergency stop button 16 is configured to be switchable between on and off, and is turned off by default. The on / off information of the emergency stop button 16 is transmitted to the emergency ECU 7.

The emergency ECU 7, the engine ECU 8, and the transmission ECU 9 are all electronic control devices (computers) mounted on the vehicle 1, and are configured as, for example, an LSI device or an embedded electronic device in which a microprocessor, ROM, RAM, etc. are integrated. , Connected to the communication line of the in-vehicle network. In this embodiment, the emergency control performed by the emergency ECU 7 and the engine ECU 8 will be focused on.

[1-2. System configuration]
The emergency control is a control that automatically brakes the vehicle 1 (emergency braking) when an abnormality occurs in the driver. In the emergency control, a predetermined braking force is applied to each wheel 14 from the main brake 5 by controlling the main brake 5. At this time, if the auxiliary brake 6 is on and the action of the auxiliary brake 6 extends to the vehicle 1, the vehicle 1 is decelerated not only by the action of the main brake 5 but also by the action of the auxiliary brake 6, so that the vehicle 1 Deceleration tends to increase. Further, the braking force of the auxiliary brake 6 may fluctuate depending on the traveling state of the vehicle 1. For example, when the auxiliary brake 6 is an exhaust brake, the braking force of the auxiliary brake 6 also decreases as the rotation speed of the engine 2 decreases as the vehicle 1 decelerates.

Therefore, the deceleration of the vehicle 1 varies according to the action of the auxiliary brake 6 even when a predetermined braking force is applied from the main brake 5 to each wheel 14. Further, the deceleration of the vehicle 1 may vary depending on the number of occupants (total weight) and the tolerance of the set pressure of the pressure reducing valve 56. Therefore, simply applying a predetermined braking force from the main brake 5 to the wheels 14 may cause a large variation in the deceleration of the vehicle 1 depending on whether the auxiliary brake 6 acts or does not act.

In the vehicle 1, the larger the deceleration, the easier it is for the occupant to lose his / her posture, and the smaller the deceleration, the longer the time and distance required to stop. Therefore, from the viewpoint of safety, in order to properly stop the vehicle 1 when the driver is abnormal, it is desirable to set the deceleration to a value within a predetermined range (suppress the variation in deceleration).

Therefore, in the emergency control of the present embodiment, instead of simply operating the main brake 5, the action of the auxiliary brake 6 is prohibited, and then the main brake 5 is controlled to apply a predetermined (constant) braking force to the wheels 14. give. As a result, when the vehicle 1 is stopped urgently, the action of the auxiliary brake 6 is eliminated (disabled), and the vehicle 1 is decelerated only by the action of the main brake 5, so that the variation in deceleration of the vehicle 1 is suppressed. Be done.

As shown in FIG. 2, the braking system 10 according to the present embodiment is composed of an emergency ECU 7 and an engine ECU 8. The emergency ECU 7 has a determination unit 7A and a braking unit 7B as elements for executing emergency control. Further, the engine ECU 8 has a control unit 8A as an element for carrying out emergency control. Here, it is assumed that all of these elements 7A, 7B, and 8A are realized by software. However, these elements 7A, 7B, and 8A may be realized by hardware (electronic circuit), or may be realized by using software and hardware in combination.

The determination unit 7A and the braking unit 7B of the present embodiment are provided as functions of the computer program (braking program) 20. In the braking system 10, emergency control is performed by the emergency ECU 7 executing the computer program 20. The computer program 20 may be provided so that it can be executed by the emergency ECU 7.

The determination unit 7A determines whether or not the vehicle 1 needs to be braked when an abnormality occurs in the driver. The determination unit 7A of the present embodiment determines that braking of the vehicle 1 is necessary when the emergency stop button 16 is pressed (switched from the off state to the on state) due to an abnormality in the driver, and other than that. In this case (when the emergency stop button 16 remains in the off state), it is determined that braking of the vehicle 1 is unnecessary. In this way, the determination unit 7A of the present embodiment determines the necessity of braking the vehicle 1 (passively) according to the operation by the driver or the passenger. The determination method by the determination unit 7A is not limited to this, and for example, instead of (or in addition to) the determination of passive movement based on the on / off information of the emergency stop button 16 described above, the posture and sensor of the driver detected by the camera. An automatic (not depending on the operation of the occupant) determination based on information such as the driver's heart rate detected in the above may be performed.

The braking unit 7B performs the above-mentioned emergency control when the determination unit 7A determines that braking is necessary. In the emergency control, the braking unit 7B prohibits the action of the auxiliary brake 6 and controls the main brake 5 to apply a predetermined braking force to the wheels 14.

In the present embodiment, since the auxiliary brake 6 is an exhaust brake and is controlled by the engine ECU 8, the braking unit 7B sends an emergency stop signal to the engine ECU 8 in the emergency control. As a result, the braking unit 7B indirectly controls the auxiliary brake 6 (via the engine ECU 8) and prohibits the operation of the auxiliary brake 6.

In the present embodiment, "prohibiting the action of the auxiliary brake 6" means controlling the auxiliary brake 6 in a non-operating state regardless of the operation of the auxiliary brake lever 15 by the driver. Therefore, in emergency control, the auxiliary brake 6 is forcibly controlled to the off state even when the auxiliary brake lever 15 is operated so that the auxiliary brake 6 operates.

Further, the braking unit 7B applies a predetermined braking force to the wheels 14 by switching the solenoid valve 57 of the main brake 5 to the ON state in the emergency control. This "predetermined braking force" is preset to a size such that the deceleration of the vehicle 1 becomes a value within a predetermined range determined from the viewpoint of safety when the vehicle 1 is stopped in an emergency. Specifically, such setting of the braking force corresponds to setting the set pressure of the pressure reducing valve 56.

The control unit 8A controls the auxiliary brake 6. The control unit 8A of the present embodiment basically controls the auxiliary brake 6 in response to the operation of the auxiliary brake lever 15 by the driver (except during the implementation of emergency control). On the other hand, when the control unit 8A receives the emergency stop signal from the braking unit 7B, the control unit 8A disregards the operation of the auxiliary brake lever 15 by the driver and sends a prohibition signal to the auxiliary brake 6 to put the auxiliary brake 6 in the inactive state. Control.

In addition to the control unit 8A, the engine ECU 8 may have a function of controlling the operating state of the engine 2 according to the amount of depression of the accelerator pedal (not shown) provided in the vehicle 1. However, during the emergency control, the operation of the accelerator pedal is invalidated so that the vehicle 1 stops after decelerating.

[1-3. flowchart]
4 and 5 are flowcharts showing an emergency control procedure (braking method) implemented by the braking system 10 described above. The flow of FIG. 4 is carried out by the emergency ECU 7, and the flow of FIG. 5 is carried out by the engine ECU 8. Each of the flows of FIGS. 4 and 5 is started when the power of the vehicle 1 is turned on, and is executed at a predetermined calculation cycle.

As shown in FIG. 4, the emergency ECU 7 first acquires the on / off information of the emergency stop button 16 (step A1), and determines whether or not the emergency stop button 16 is in the on state (step A2). Step A2 is a process (determination step) performed by the determination unit 7A. If the emergency stop button 16 is in the off state, no abnormality has occurred in the driver, and it is determined in step A2 that braking of the vehicle 1 is unnecessary. Therefore, the solenoid valve 57 is controlled to be in the off state (step A5), and an emergency is performed. This flow is returned without any control being implemented. On the other hand, if the emergency stop button 16 is in the ON state, an abnormality has occurred in the driver, and it is determined in step A2 that braking of the vehicle 1 is necessary, so emergency control is performed (steps A3 and A4).

Steps A3 and A4 are processes (braking steps) performed in the braking unit 7B. In step A3, an emergency stop signal is transmitted to the control unit 8A (transmission step). As a result, the action of the auxiliary brake 6 is prohibited. Further, in the following step A4, the solenoid valve 57 is switched to the ON state. That is, in step A4, the main brake 5 is controlled and a predetermined braking force is applied to the wheels 14. Then, this flow is returned. If the emergency stop button 16 remains on in the next calculation cycle, the process proceeds from step A2 to step A3 again, and the emergency control is continued. As a result, the vehicle 1 stops after decelerating.

As shown in FIG. 5, the engine ECU 8 first acquires various information including the operation position of the auxiliary brake lever 15 (step B1), and determines whether or not an emergency stop signal has been received (step B2). If the emergency stop signal is not transmitted from the braking unit 7B of the emergency ECU 7 (emergency control is not implemented), the engine ECU 8 does not receive the emergency stop signal. The operating state of the auxiliary brake 6 is controlled according to the operating position of 15, and this flow is returned.

On the other hand, when the emergency stop signal is transmitted from the braking unit 7B of the emergency ECU 7 (after the execution of step A3 in the flow of FIG. 4), the emergency stop signal is received by the engine ECU 8, and therefore steps B2 to B4 Proceed to. Step B4 is a process (control step) performed by the control unit 8A. In step B4, the operating position of the auxiliary brake lever 15 is ignored, a prohibition signal is transmitted to the auxiliary brake 6, and the auxiliary brake 6 is controlled to be inactive. Then, this flow is returned. If an emergency stop signal is received by the engine ECU 8 even in the next calculation cycle (if the emergency stop button 16 remains on), the process proceeds from step B2 to step B4 again, and the auxiliary brake 6 is inactive. Continue to be controlled by.

[1-4. effect]
According to the braking system 10, the braking method, and the computer program 20 described above, when it is determined that braking of the vehicle 1 is necessary due to an abnormality in the driver, the operation of the auxiliary brake 6 is prohibited and the main brake 5 is prohibited. A predetermined braking force is applied to the wheel 14. Therefore, when an abnormality occurs in the driver, the action of the auxiliary brake 6 is eliminated (disabled), and then the action of the main brake 5 can decelerate the vehicle 1. Therefore, it is possible to suppress variations in the deceleration of the vehicle 1. Therefore, the vehicle 1 can be braked more appropriately when the driver is abnormal. Therefore, the vehicle 1 can be stopped more appropriately in an emergency.

When a braking system provided with an electronic control system is applied, the braking force applied to the wheels is variable by electronic control, so that the deceleration of the vehicle 1 can be adjusted. However, the cost increases when such an electronic control system is provided. On the other hand, as described above, if the operation of the auxiliary brake 6 is prohibited and a predetermined braking force is applied from the main brake 5 to the wheels 14, even if the main brake 5 is not provided with an electronic control system, It is possible to suppress variations in the deceleration of the vehicle 1 when the driver is abnormal. Therefore, the vehicle 1 can be braked more appropriately when the driver is abnormal while suppressing the cost.

If the auxiliary brake 6 is controlled to be inactive by sending an emergency stop signal to the control unit 8A that controls the auxiliary brake 6, the auxiliary brake 6 can be operated only by setting (changing) the control logic. The action can be prohibited. Therefore, since it is not necessary to change the mechanical structure, the design cost can be suppressed, and the auxiliary brake 6 having various structures can be easily applied.

In addition to the air tank 51 and the air pipe 53, the main brake 5 described above is provided with the other air pipe 55, the pressure reducing valve 56, the solenoid valve 57, and the double check valve 58. Therefore, the solenoid valve is provided when the driver is abnormal. A predetermined braking force can be applied from the main brake 5 to the wheels 14 only by switching the 57 to the on state. Therefore, by simply adding the above-mentioned devices 55 to 58 to the existing braking system, it is possible to suppress variations in the deceleration of the vehicle 1 when the driver is abnormal. Therefore, the existing brake system can be utilized, and the cost can be suppressed.

[2. Second embodiment]
[2-1. System configuration]
FIG. 6 is a block diagram of the braking system 10'according to the second embodiment. Hereinafter, the same or corresponding elements as those described in the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. As shown in FIG. 6, the braking system 10'according to the present embodiment includes an emergency ECU 7 and a transmission ECU 9 (control device). In this embodiment, emergency control is performed by the emergency ECU 7 and the transmission ECU 9. Since the engine ECU 8 of the present embodiment does not perform emergency control, the above-mentioned control unit 8A is omitted.

Also in the emergency control of the present embodiment, the braking unit 7B prohibits the action of the auxiliary brake 6 and controls the main brake 5 to apply a predetermined braking force to the wheels 14. However, in the emergency control, the braking unit 7B of the present embodiment sends an emergency stop signal to the transmission ECU 9 instead of sending the emergency stop signal to the engine ECU 8 described above. As a result, the braking unit 7B indirectly controls the transmission 3 (via the transmission ECU 9) to put the transmission 3 in the neutral state. Specifically, the braking unit 7B controls the disconnection mechanism 3A to block the transmission of power from the engine 2 to the wheels 14, thereby prohibiting the action of the auxiliary brake 6 as an engine brake.

As described above, in the present embodiment, "prohibiting the action of the auxiliary brake 6" means to put the transmission 3 in the neutral state regardless of the operation of the gear shift selector 18 by the driver (transmission of power from the engine 2 to the wheels 14). By shutting off), even if the auxiliary brake 6 is operating, it means that the action of the auxiliary brake 6 does not reach. Therefore, in the emergency control of the present embodiment, even when the gear shift selector 18 is operated so that the transmission 3 is not in the neutral state (specifically, the operation position of the gear shift selector 18 is other than the N range). Even if there is, the transmission 3 is controlled to the neutral state, and the transmission of power from the engine 2 functioning as the auxiliary brake 6 to the wheels 14 is cut off by the disconnection mechanism 3A.

The transmission ECU 9 of the present embodiment has a shift control unit 9A that controls the transmission 3 according to the operation position of the gear shift selector 18. The shift control unit 9A basically controls the transmission 3 according to the operation of the gear shift selector 18 by the driver (except during the emergency control). On the other hand, when the shift control unit 9A receives the emergency stop signal from the braking unit 7B, the shift control unit 9A disregards the operation of the gear shift selector 18 by the driver and transmits a neutral signal to the transmission 3 to put the transmission 3 in the neutral state. The transmission of power from the engine 2 to the wheels 14 is cut off by the disconnection mechanism 3A.

[2-2. flowchart]
7 and 8 are flowcharts showing an emergency control procedure (braking method) implemented by the braking system 10'according to the present embodiment. The flow of FIG. 7 is carried out by the emergency ECU 7, and the flow of FIG. 8 is carried out by the transmission ECU 9. Each of the flows of FIGS. 7 and 8 is started when the power of the vehicle 1 is turned on, and is executed at a predetermined calculation cycle. In FIG. 7, the same reference numerals are given to the same or corresponding procedures (steps) as those described in the first embodiment.

As shown in FIG. 7, the emergency ECU 7 of the present embodiment also carries out the above-mentioned process of step A1 and the determination of step A2. Then, if the emergency stop button 16 is in the off state, the solenoid valve 57 is controlled to the off state (step A5), the flow is returned, and if the emergency stop button 16 is in the on state, emergency control is executed (step A3). ′, A4).

Steps A3'and A4 are processes (braking steps) performed in the braking unit 7B. In step A3'of this embodiment, an emergency stop signal is transmitted to the transmission ECU 9 (transmission step). As a result, the transmission 3 is controlled to be in the neutral state, so that the transmission of power from the engine 2 to the wheels 14 is cut off by the disconnection mechanism 3A. As a result, the action of the auxiliary brake 6 is prohibited. Then, the process of step A4 described above is executed, and this flow is returned. If the emergency stop button 16 remains in the ON state even in the next calculation cycle, the process proceeds from step A2 to step A3'again, and emergency control is continued.

As shown in FIG. 8, the transmission ECU 9 first acquires various information including the operation position of the gear shift selector 18 (step C1), and determines whether or not an emergency stop signal has been received (step C2). If the emergency stop signal is not transmitted from the braking unit 7B of the emergency ECU 7 (emergency control is not implemented), the transmission ECU 9 does not receive the emergency stop signal, so the process proceeds to step C3 and the gear shift control unit 9A shifts gears. The operation of the transmission 3 is controlled according to the operation position of the selector 18, and this flow is returned.

On the other hand, when the emergency stop signal is transmitted from the braking unit 7B of the emergency ECU 7 (after the execution of step A3'in the flow of FIG. 7), the transmission ECU 9 receives the emergency stop signal, so that the emergency stop signal is received from step C2. Proceed to step C4. Step C4 is a process (control step) executed by the shift control unit 9A. In step C4, the operating position of the gear shift selector 18 is ignored, and the transmission 3 is controlled to the neutral state. Then, this flow is returned. If an emergency stop signal is received by the transmission ECU 9 in the next calculation cycle (if the emergency stop button 16 remains on), the process proceeds from step C2 to step C4 again, and the transmission 3 is in the neutral state. Continue to be controlled by.

[2-3. effect]
When the auxiliary brake 6 increases the absorbed horsepower of the engine 2, the absorbed horsepower of the engine 2 does not affect the rotation of the wheels 14 by blocking the transmission of the power from the engine 2 to the wheels 14. Therefore, when it is determined that braking of the vehicle 1 is necessary due to an abnormality in the driver, the auxiliary brake 6 acts by controlling the disconnection mechanism 3A to cut off the transmission of power from the engine 2 to the wheels 14. Can be banned. Therefore, also in this embodiment, it is possible to suppress the variation in deceleration of the vehicle 1 as in the first embodiment described above. Therefore, the vehicle 1 can be braked more appropriately when the driver is abnormal.

Further, since the absorption horsepower of the engine 2 increases as the rotation speed increases, the traveling speed of the vehicle 1 is high when the disconnection mechanism 3A is in a state where the power transmission from the engine 2 to the wheels 14 is connected. The more the engine brake acting on the wheel 14, increases. On the other hand, in the present embodiment, when it is determined that braking of the vehicle 1 is necessary due to an abnormality in the driver, the disconnection mechanism 3A is controlled and the power transmission between the engine 2 and the wheels 14 is mechanical. Therefore, it is possible to prevent the engine brake from acting on the wheels 14. Therefore, the variation in deceleration of the vehicle 1 due to the engine brake can be suppressed. Therefore, the vehicle 1 can be braked more appropriately when the driver is abnormal.

Further, if the action of the auxiliary brake 6 is prohibited as described above by using the disconnection mechanism 3A for putting the transmission 3 in the neutral state, a new disconnection is made to the power transmission path between the engine 2 and the wheel 14. The transmission of power from the engine 2 to the wheels 14 can be mechanically cut off without providing the contact mechanism. Therefore, an increase in device cost can be suppressed. Also in this embodiment, the same action and effect can be obtained from the same configuration as in the first embodiment described above.

[3. Modification example]
The configuration of the main brake 5 described above is an example. The braking mechanism 52 is not limited to the drum brake, and may be, for example, a disc brake. Further, the main brake 5 may be a hydraulic brake controlled by hydraulic pressure, or may be an air-hydraulic combined brake that is a combination of an air brake and a hydraulic brake.

In the second embodiment, the control target of the braking unit 7B and the braking process may be any connection / disconnection mechanism that connects / disconnects the transmission of power from the engine 2 to the wheels 14, and is limited to the connection / disconnection mechanism 3A included in the transmission 3. Not done. For example, when the transmission 3 is a so-called AMT (Automated Manual Transmission) that automates the switching of the shift stage and the disengagement and disengagement of the clutch based on the manual transmission, the torque converter 4 is omitted and the transmission with the engine 2 is performed. Since a clutch (disengagement mechanism) is interposed with the machine 3, this clutch may be controlled in place of the above-mentioned disengagement mechanism 3A. Also in this case, if the clutch is controlled to the released state and the power transmission from the engine 2 to the wheels 14 is cut off when the driver is abnormal, the action of the auxiliary brake 6 is prohibited, so that the same as in the second embodiment described above. Actions and effects can be obtained.

When the transmission 3 is AMT, the operation of the auxiliary brake 6 may be prohibited by setting the transmission 3 in the neutral state as in the second embodiment described above. Further, the transmission 3 may be a manual transmission whose gear ratio is changed according to a shift operation (shift operation) by the driver. Even when a manual transmission is applied as the transmission 3, for example, as in the first embodiment described above, if the braking unit 7B transmits an emergency stop signal to the control unit 8A to prohibit the action of the auxiliary brake 6. As described above, the variation in deceleration of the vehicle 1 can be suppressed. Therefore, the vehicle 1 can be braked more appropriately as in the above-described embodiment.

In the above-described embodiment, only the elements 7A, 7B, 8A, and 9A related to emergency control are exemplified as the elements provided in the emergency ECU 7, the engine ECU 8, and the transmission ECU 9, but the configurations of the respective ECUs 7 to 9 are not limited thereto. For example, the emergency ECU 7 may further have an element (function) for notifying an abnormality of the driver during the execution of emergency control. Further, the determination unit 7A and the braking unit 7B and the control unit 8A or the shift control unit 9A described above may be integrated in one computer, or may be provided in different computers. The control unit 8A or the shift control unit 9A may be provided as a function of the computer program 20 together with the determination unit 7A and the braking unit 7B.

Further, in the first embodiment described above, the case where the braking unit 7B indirectly controls the auxiliary brake 6 (via the engine ECU 8) is illustrated, but the braking unit 7B directly controls the auxiliary brake 6 (engine ECU 8). The action of the auxiliary brake 6 may be prohibited by controlling the brake (without using). Similarly, in the second embodiment described above, the case where the braking unit 7B indirectly controls the transmission 3 (via the transmission ECU 9) is illustrated, but the braking unit 7B directly controls the transmission 3 (via the transmission ECU 9). The operation of the auxiliary brake 6 may be prohibited by controlling (without using the transmission ECU 9).

1 Vehicle 2 Engine 3 Transmission 3A Disconnection mechanism 5 Main brake 6 Auxiliary brake 7 Emergency ECU
7A Judgment unit 7B Braking unit 8 Engine ECU
8A Control unit 9 Transmission ECU (control device)
9A Shift control unit 10,10'Brake system (emergency braking system)
14 Wheels 17 Brake Pedal 18 Gear Shift Selector 20 Computer Program (Emergency Braking Program)
51 Air tank 52 Braking mechanism 53 Air piping 55 Air piping 56 Pressure reducing valve 57 Solenoid valve 58 Double check valve

Claims (9)

An emergency braking system for a vehicle provided with a main brake that applies braking force to the wheels and an auxiliary brake that assists the main brake.
A determination unit that determines at least one of passive and automatic braking of the vehicle when an abnormality occurs in the driver.
When the determination unit determines that the braking is necessary, the auxiliary brake is prohibited from operating, and the braking unit that controls the main brake to give a predetermined braking force to the wheels is provided. An emergency braking system that features this. A control unit that controls the auxiliary brake in response to an operation by the driver is provided.
When the determination unit determines that the braking is necessary, the braking unit transmits an emergency stop signal to the control unit.
The emergency braking system according to claim 1, wherein when the control unit receives the emergency stop signal, the control unit ignores the operation and controls the auxiliary brake to a non-operating state. The vehicle is provided with an engine as a drive source and a connection / disconnection mechanism for connecting / disconnecting the transmission of power from the engine to the wheels.
The auxiliary brake increases the absorbed horsepower of the engine in response to an operation by the driver.
The emergency braking system
A control device for controlling the disconnection mechanism is provided.
The braking unit transmits an emergency stop signal to the control device when the determination unit determines that the braking is necessary.
The emergency braking system according to claim 1, wherein the control device controls the disconnection mechanism to cut off the transmission of the power when the emergency stop signal is received. The vehicle is provided with a transmission that includes the disconnection mechanism and is in a neutral state with the disconnection mechanism blocking the transmission of power.
The control device includes a shift control unit that controls the transmission in response to an operation of the driver on the gear shift selector.
The emergency braking system according to claim 3, wherein the shift control unit controls the transmission to the neutral state by ignoring the operation to the gear shift selector when the emergency stop signal is received. .. This is an emergency braking method for a vehicle provided with a main brake that applies braking force to the wheels and an auxiliary brake that assists the main brake.
A determination process for determining the necessity of braking the vehicle when an abnormality occurs in the driver, at least one of passive and automatic.
When it is determined in the determination step that the braking is necessary, the operation of the auxiliary brake is prohibited, and the braking step of controlling the main brake to give a predetermined braking force to the wheels is provided. An emergency braking method characterized by that. The braking step includes a transmission step of transmitting an emergency stop signal to a control unit that controls the auxiliary brake in response to an operation by the driver.
The emergency braking method is
The emergency braking method according to claim 5, further comprising a control step of ignoring the operation and controlling the auxiliary brake to a non-operating state after the transmission step is performed. The vehicle is provided with an engine as a drive source and a connection / disconnection mechanism for connecting / disconnecting the transmission of power from the engine to the wheels.
The auxiliary brake increases the absorbed horsepower of the engine in response to an operation by the driver.
The braking step includes a transmission step of transmitting an emergency stop signal to a control device that controls the disconnection mechanism.
The emergency braking method is
The emergency braking method according to claim 5, further comprising a control step of controlling the disconnection mechanism to cut off the transmission of the power after the transmission step is performed. The vehicle is provided with a transmission that includes the disconnection mechanism and is in a neutral state with the disconnection mechanism blocking the transmission of power.
The emergency braking method according to claim 7, wherein in the control step, the transmission is controlled to the neutral state while ignoring the operation of the driver to the gear shift selector. An emergency braking program for a vehicle provided with a main brake that applies braking force to the wheels and an auxiliary brake that assists the main brake.
A determination process for determining the necessity of braking the vehicle when an abnormality occurs in the driver, at least one of passive and automatic.
When it is determined in the determination step that the braking is necessary, the computer executes a braking step of prohibiting the action of the auxiliary brake and controlling the main brake to give a predetermined braking force to the wheels. An emergency braking program characterized by letting.

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