CN114728650B - Air pressure control device, air pressure control method, and air pressure control program for brake - Google Patents

Abstract

The air pressure control device is provided with: an air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and a control unit configured to control the air pressure supplied from the air pressure circuit to the brake mechanism, wherein the control unit is configured to supply air to the brake mechanism based on a signal for stopping the vehicle in an emergency to decelerate the vehicle, and to decompress the air pressure supplied to the brake mechanism when the vehicle is at or below a predetermined speed.

Description

Air pressure control device, air pressure control method and air pressure control program for brake

Technical Field

The present disclosure relates to an air pressure control device, an air pressure control method and an air pressure control program.

Background Art

In the case where the driver suddenly cannot continue to drive safely during driving due to a sudden change in the physical condition of the driver, as an emergency measure, guidelines for driver abnormality response systems are formulated to stop the vehicle through the operation of passengers other than the driver (for example, see non-patent document 1). In addition, various braking systems are proposed according to the guidelines.

Prior art literature

Non-patent literature

Non-patent document 1: Basic design document for the emergency response system (deceleration and stop type), March 2009, Advanced Safety Autonomous Vehicle Promotion Seminar, Ministry of Land, Infrastructure, Transport and Tourism Bureau

Summary of the invention

Problem that the invention aims to solve

In addition, in the above-mentioned braking system, when the vehicle is stopped in an emergency, it is required to stop the vehicle quickly but safely. In other words, it is required to suppress the load applied to the occupants when the vehicle is stopped in an emergency.

An object of the present disclosure is to provide an air pressure control device, an air pressure control method, and an air pressure control program that can suppress a load applied to an occupant when a vehicle stops suddenly.

Solutions for solving problems

According to one embodiment of the present disclosure, an air pressure control device is provided. The air pressure control device includes: an air pressure circuit configured to supply air to a brake mechanism for applying braking force to wheels; and a control unit configured to control the air pressure supplied from the air pressure circuit to the brake mechanism, wherein the control unit is configured to supply air to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle, and to reduce the air pressure supplied to the brake mechanism when the vehicle reaches a predetermined speed or less.

According to the above structure, when the vehicle is decelerating and the speed is below the specified speed, the air pressure supplied to the brake mechanism is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

In the air pressure control device described above, the control unit may be configured to increase the depressurized air pressure to a predetermined value or more after a predetermined time has elapsed since the vehicle speed becomes equal to or lower than the predetermined speed.

According to the above configuration, the vehicle stops after a predetermined time has passed since the vehicle speed reaches a predetermined speed or less. Therefore, the air pressure supplied to the brake mechanism is increased to a predetermined value or more to increase the braking force of the brake mechanism, thereby preventing the vehicle from moving from the stopped state.

In the air pressure control device described above, the control unit may be configured to increase the air pressure supplied to the brake mechanism to a predetermined value or more after a predetermined time has passed since the air pressure became equal to or less than a lower limit pressure due to the pressure reduction.

According to the above configuration, the vehicle stops after a predetermined time has passed since the pressure fell below the lower limit. Therefore, the air pressure supplied to the brake mechanism is increased to a predetermined value or more to increase the braking force of the brake mechanism, thereby preventing the vehicle from moving from the stopped state.

In the air pressure control device described above, the control unit may be configured to fix the air pressure supplied to the brake mechanism to the upper limit pressure when the air pressure supplied to the brake mechanism becomes equal to or higher than an upper limit pressure during deceleration of the vehicle.

According to the above configuration, when the vehicle is decelerated to a certain extent during deceleration, the braking force of the braking mechanism can be made constant by making the air pressure supplied to the braking mechanism constant, thereby suppressing a sudden change in speed.

In the above-mentioned air pressure control device, the control unit may be configured to determine the air pressure supplied to the brake mechanism at predetermined time intervals.

According to the above configuration, the air pressure supplied to the brake mechanism is determined at predetermined time intervals. Therefore, the amount of calculation can be reduced compared to a case where the air pressure supplied to the brake mechanism is determined at any time.

In the above-mentioned air pressure control device, the air pressure circuit may be configured to supply air to the brake mechanism instead of a brake valve that supplies air to the brake mechanism when a brake operation is performed.

According to the above structure, the brake valve usually supplies air to the brake mechanism according to the driver's brake operation. However, when the driver is abnormal, the air pressure circuit is controlled by the control unit to supply air to the brake mechanism instead of the brake valve, thereby enabling the vehicle to be stopped urgently.

The air pressure control device may be configured such that, when an abnormality signal indicating an abnormality based on the operation of the passenger switch is obtained as a signal for causing the vehicle to stop urgently, the control unit supplies air pressure for slow braking to the brake mechanism. According to the above structure, if the emergency brake is immediately applied after the operation of the passenger switch, the passenger panics, and therefore, attention can be called by first applying slow braking to the brake mechanism.

For the above-mentioned air pressure control device, it can also be that the air pressure circuit is constructed to have a first port connected to the vehicle's air tank, a second port connected to the brake valve that outputs an air pressure signal when a braking operation is performed, and a third port connected to a braking mechanism that applies braking force to the wheel based on the air pressure signal, and switches between a first connection state in which air is supplied from the second port to the third port and a second connection state in which air is supplied from the first port to the third port, and the control unit is constructed to switch the air pressure circuit from the first connection state to the second connection state based on a signal for emergency stopping of the vehicle.

According to the above structure, the first communication state in which the brake valve is connected to the brake mechanism to supply air from the second port to the third port is switched to the second communication state in which the air tank is connected to the brake mechanism to supply air from the first port to the third port. Therefore, air can be automatically supplied from the air tank to the brake mechanism to generate braking force.

According to one embodiment of the present disclosure, there is provided an air pressure control method of an air pressure control device. The air pressure control device comprises: an air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and a control unit configured to control the air pressure supplied from the air pressure circuit to the brake mechanism. The air pressure control method comprises: a deceleration step of supplying air to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle; and an air pressure reduction step of reducing the air pressure supplied to the brake mechanism when the vehicle becomes below a predetermined speed during the deceleration.

According to the above method, when the vehicle is decelerating and the speed is below the specified speed, the air pressure supplied to the brake mechanism is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

According to one embodiment of the present disclosure, an air pressure control program of an air pressure control device is provided. The air pressure control device comprises: an air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and a control unit configured to control the air pressure supplied from the air pressure circuit to the brake mechanism. When the air pressure control program is executed in a computer of the air pressure control device, the air pressure control device executes: a deceleration step of supplying air to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle; and an air pressure reduction step of reducing the air pressure supplied to the brake mechanism when the vehicle becomes below a specified speed during the deceleration.

According to the above program, when the vehicle is decelerating and the speed is below the specified speed, the air pressure supplied to the brake mechanism is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

According to one embodiment of the present disclosure, a non-transitory computer-readable medium for storing an air pressure control program is provided. When the air pressure control program is executed in a computer of an air pressure control device, the air pressure control device is caused to execute a deceleration step and an air pressure reduction step. The air pressure control device comprises: an air pressure circuit configured to supply air to a brake mechanism for applying a braking force to a wheel; and a control unit configured to control the air pressure supplied from the air pressure circuit to the brake mechanism, wherein in the deceleration step, air is supplied to the brake mechanism based on a signal for emergency stopping the vehicle to decelerate the vehicle, and in the air pressure reduction step, the air pressure supplied to the brake mechanism is reduced when the vehicle becomes below a predetermined speed during the deceleration.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing the overall structure of an air pressure brake system including an air pressure control device according to one embodiment of the air pressure control device.

FIG. 2 is a perspective view showing the appearance of the air pressure control device according to the embodiment.

FIG. 3 is a schematic diagram of the abnormality handling system according to the embodiment.

FIG. 4 is a circuit diagram of a first communication state in which the brake valve and the brake mechanism are communicated with each other as the air pressure circuit of the embodiment.

FIG. 5 is a circuit diagram of a second communication state in which the air tank and the brake mechanism are communicated with each other as the air pressure circuit of the embodiment.

FIG. 6 is a flowchart showing a processing procedure of the abnormality handling system according to the embodiment.

FIG. 7 is a graph showing a control example of the abnormality handling system according to the embodiment.

FIG. 8 is a flowchart showing a processing procedure of the abnormality handling system according to the embodiment.

FIG. 9 is a graph showing a modification of the control example of the abnormality handling system.

FIG. 10 is a schematic diagram showing a part of an air pressure brake system including an air pressure control device according to a modification of the air pressure control device.

FIG. 11 is a schematic diagram showing a part of an air pressure brake system including an air pressure control device according to a modification of the air pressure control device.

DETAILED DESCRIPTION

One embodiment of an air pressure control device and an air pressure circuit provided in the air pressure control device will be described with reference to Figures 1 to 8. The air pressure control device is provided in an air pressure brake system mounted on a vehicle such as a bus.

As shown in FIG1 , the air pressure brake system 11 mounted on the vehicle 10 is a full air brake system that uses an air pressure-controlled brake mechanism command system and has an air pressure-driven brake mechanism. The air pressure brake system 11 is provided with an air tank 12 for storing compressed air generated by a compressor (not shown). The air tank 12 has a first tank 12A, a second tank 12B, and a third tank 12C. For example, the first tank 12A is a tank for storing compressed air for applying braking force to the front wheels of the vehicle 10. The second tank 12B is a tank for storing compressed air for applying braking force to the rear wheels. In addition, the third tank 12C is a tank for storing compressed air used for other purposes. The first tank 12A is connected to the rear pressure chamber 13B of the brake valve 13, and the second tank 12B is connected to the front pressure chamber 13A of the brake valve 13. In addition, the first tank 12A and the second tank 12B are connected to the air horn device 14B via the protection valve 14A.

In addition, the brake valve 13 is connected to the relay valve 15 via an air pipe 18. When the driver operates the brake pedal 13C of the brake valve 13, an air pressure signal is output from the brake valve 13 to the relay valve 15. In addition, the relay valve 15 is connected to the air tank 12 via an air pipe not shown. When the air pressure signal is input from the brake valve 13 to the relay valve 15, a large amount of compressed air stored in the air tank 12 is supplied to the relay valve 15 via the air pipe. The large amount of compressed air supplied to the relay valve 15 is supplied to the brake chamber 17 via the ABS (Anti-lock Brake System) control valve 16. The brake chamber 17 generates braking force on the wheel due to the air being supplied. The ABS control valve 16 and the brake chamber 17 constitute an air pressure driven brake mechanism.

When an abnormality response system for stopping a vehicle by an operation of a passenger other than the driver is mounted on an air pressure brake system 11 of an existing vehicle (existing vehicle), a pressure control module (PCM: Pressure Control Module) 20 is provided in the middle of an air piping 18 connecting the brake valve 13 and the relay valve 15 of the command system. The pressure control module 20 has: a first port P1 connected to the air tank 12 (third air tank 12C); a second port P2 connected to the brake valve 13; and a third port P3 connected to a brake mechanism including the relay valve 15. The pressure control module 20 corresponds to an air pressure control device. In addition, the pressure control module 20 is provided between the brake valve 13 and the relay valve 15, so it can also be installed in an air pressure brake system 11 having a brake mechanism other than an air pressure driven type.

Next, the structure including the appearance of the pressure control module 20 will be described with reference to FIG. 2 .

As shown in FIG2 , the pressure control module 20 includes a housing 210 for accommodating a control device, etc. The housing 210 is formed of, for example, a resin. A main body 211 having a flow path, etc. is connected to the housing 210. The main body 211 is formed by, for example, a casting method such as aluminum die casting. A port connection portion 212 for connecting various ports is provided on the main body 211. A pair of second ports P2 are provided on a first surface 213 of the port connection portion 212.

A pair of third ports P3 is provided on a second surface 214 of the port connection portion 212 perpendicular to the first surface 213 provided with the second ports P2. A first port P1 is provided near the third ports P3 and is connected to a first supply path 23 for supplying compressed air from the gas tank 12.

A discharge portion 58 containing a silencer is provided on the lower side of the main body 211. In addition, a protrusion 215 protruding toward the back side is provided on the main body 211. In addition, a connection portion (not shown) is provided on the lower surface of the housing 210, and the connection portion connects the control device etc. housed in the housing 210 to the cable of the electrical system for the external power supply or the vehicle network.

As described above, the pressure control module 20 is a unit obtained by integrating a control device for controlling an air pressure circuit with a flow path. When the pressure control module 20 is installed on the vehicle 10, the protrusion 215 is fixed at a predetermined position of the vehicle body. In addition, the first port P1 is connected to the piping connected to the air tank 12, the second port P2 is connected to the piping connected to the brake valve 13, and the third port P3 is connected to the relay valve 15. In addition, the cables of the electrical system are connected to the connection part. In other words, the pressure control module 20 may be the only main component installed in the air pressure brake system 11 for abnormal response.

3 , the air pressure circuit of the pressure control module 20 will be described in detail.

The pressure control module 20 includes an air pressure circuit 22 and a sub-ECU (Electronic Control Unit) 32. The pressure control module 20 and the main ECU 31 constitute an abnormality response system 50. The main ECU 31 may be provided outside the housing 210 or may be accommodated inside the housing 210.

The main ECU 31 and the sub-ECU 32 are respectively equipped with a computing unit, a communication interface unit, a volatile storage unit, and a non-volatile storage unit. The computing unit is a computer processor that controls the air pressure brake system 11 according to the control program stored in the non-volatile storage unit (storage medium). The computing unit can also implement at least a part of the processing performed by itself through circuits such as ASIC. The control program can be executed by one computer processor or by multiple computer processors. In addition, the main ECU 31 and the sub-ECU 32 are connected to vehicle networks such as CAN (Controller Area Network) 33 to send and receive various information to each other. In addition, the control program includes an air pressure control program. In addition, the main ECU 31 performs control based on the air pressure control method. In addition, the air pressure control program can also be stored in a non-temporary computer-readable medium.

When the driver's seat operation switch 51 and the release switch 52 are turned on, the main ECU 31 inputs the on signal output from them. The driver's seat operation switch 51 and the release switch 52 are switches that are assumed to be operated by the driver and are arranged near the driver's seat. When the driver's seat operation switch 51 is turned on, the abnormal response system 50 operates. The release switch 52 is a switch for stopping the operation of the abnormal response system 50 in the case of the abnormal response system 50 being erroneously started, etc. In addition, the on signal output by the driver's seat operation switch 51 is equivalent to a signal for emergency stopping of the vehicle.

In addition, when the passenger seat operation switch 53 is turned on, the main ECU 31 inputs the on signal outputted from them. The passenger seat operation switch 53 is a switch that is assumed to be operated by a passenger other than the driver. The passenger seat operation switch 53 is provided at a position other than the driver's seat and can be operated by a passenger other than the driver. In addition, the on signal outputted by turning on the passenger seat operation switch 53 is equivalent to a signal for emergency stopping the vehicle.

The main ECU 31 obtains acceleration information from the acceleration sensor 54 via the CAN 33. The main ECU 31 directly obtains vehicle speed information from the vehicle speed sensor 55. When the abnormal response system 50 starts to work, the main ECU 31 calculates the target air pressure of the air pressure brake system 11 in such a way that the deceleration obtained from the vehicle speed is close to the target deceleration as the target value, and indicates the calculated target air pressure to the sub-ECU 32. The target deceleration can be changed by updating the data stored in the storage unit such as the main ECU 31. For example, when the vehicle 10 is a public bus, it is assumed that there are standing passengers in the vehicle, so the absolute value of the target deceleration is small. In addition, when the vehicle 10 is a high-speed bus with all passengers seated, the absolute value of the target deceleration can be large compared to the public bus. In addition, the target deceleration can also be changed according to the weight and length of the vehicle 10.

Furthermore, when the abnormality response system 50 is activated, the main ECU 31 outputs an instruction signal to the in-cabin device 56 and the out-cabin device 57. The in-cabin device 56 is, for example, an accelerator interlock mechanism that makes it impossible to operate the accelerator pedal. When the abnormality response system 50 is activated, the main ECU 31 operates the accelerator interlock mechanism. In addition, as the in-cabin device 56, a notification buzzer provided in the cabin, a notification lamp provided in the cabin, etc. may also be provided. For example, when the abnormality response system 50 is activated, the main ECU 31 outputs a sound from the notification buzzer, and turns on or flashes the notification lamp. The out-cabin device 57 is, for example, an air horn device 14B (refer to FIG. 1 ), a hazard indicator lamp, a brake lamp, etc. For example, when the abnormality response system 50 is activated, the main ECU 31 drives the protection valve 14A, etc. to supply air to the air horn device 14B to generate a warning sound, and turns on or flashes the hazard indicator lamp and the brake lamp.

The sub-ECU 32 is housed in the housing 210 of the pressure control module 20 and is used to control various valves of the pressure control module 20. The pressure control module 20 has a first supply path 23 connected to the air tank 12. The first supply path 23 is connected to a front air supply path 37 and a rear air supply path 38. The front air supply path 37 is connected to the brake chamber 17 of the front wheel via the relay valve 15, and the rear air supply path 38 is connected to the brake chamber 17 of the rear wheel. A pair of third ports P3 are connected to the front air supply path 37 and the rear air supply path 38, respectively.

A relay valve 25 is connected to the middle of the first supply path 23. The relay valve 25 has a discharge port 25A. The discharge port 25A is connected to a discharge portion 58 having a muffler. In addition, the relay valve 25 has a pilot port 25B. The pilot port 25B is connected to a branch path 26 branched from the first supply path 23. When the air pressure applied from the branch path 26 to the pilot port 25B is a predetermined pressure such as atmospheric pressure, the first supply path 23 is cut off due to the force of a force spring or the like. When the relay valve 25 is in the exhaust state, the air flow from the gas tank 12 to the front air supply path 37 and the rear air supply path 38 is cut off. In addition, when the relay valve 25 is in the exhaust state, the downstream side of the relay valve 25 in the first supply path 23 is connected to the discharge portion 58, and the compressed air on the downstream side of the relay valve 25 in the first supply path 23 is discharged, thereby becoming a predetermined pressure such as atmospheric pressure.

On the other hand, when the air pressure applied from the branch path 26 to the pilot port 25B reaches a driving pressure greater than a predetermined pressure such as atmospheric pressure, the relay valve 25 resists the force of the force spring and becomes a supply state in which the first supply path 23 is connected. When the relay valve 25 is in the supply state, air is supplied from the air tank 12 to the front air supply path 37 and the rear air supply path 38. When the relay valve 25 is in the supply state, the first supply path 23 is connected to the front air supply path 37 and the rear air supply path 38. In addition, when the pressure on the outlet side (secondary side) is too high, the relay valve 25 cuts off the connection state of the first supply path 23 and becomes an exhaust state.

One end of the branch road 26 is connected to the first supply path 23, and the other end is connected to the discharge portion 58. An intake valve 27 and an exhaust valve 28 are provided in the middle of the branch road 26. The intake valve 27 and the exhaust valve 28 are electromagnetic valves, which are driven by the sub-ECU 32. The intake valve 27 is provided in the branch road 26 at a position upstream (close to the gas tank 12) than the exhaust valve 28. The intake valve 27 switches its operation by turning the power on and off (driven/non-driven) from the sub-ECU 32 via the wiring 27A. The intake valve 27 is in a closed position to close the branch road 26 in a non-driven state in which the power is disconnected. In addition, the intake valve 27 is in an open position to open the branch road 26 in a driven state in which the power is connected.

The exhaust valve 28 is an electromagnetic valve that switches its action by turning the power on and off (driven/non-driven) from the sub-ECU 32 via the wiring 28A. The exhaust valve 28 is in an open position that connects the branch path 26 in a non-driven state in which the power is cut off. In addition, the exhaust valve 28 is in a closed position that closes the branch path 26 in a driven state in which the power is turned on. That is, when the intake valve 27 is in a closed position in a non-driven state, the exhaust valve 28 opens the portion that is more downstream than the intake valve 27 and the signal supply path 29 to the atmosphere. In addition, the exhaust valve 28 makes the upstream side of the intake valve 27 in the branch path 26 and the upstream side of the relay valve 25 in the first supply path 23 to the atmospheric pressure in the driven state.

In addition, a first pressure sensor 35 and a signal supply path 29 for supplying an air pressure signal to the relay valve 25 are connected between the intake valve 27 and the exhaust valve 28 in the branch passage 26. The first pressure sensor 35 detects the pressure between the intake valve 27 and the exhaust valve 28 in the branch passage 26 and outputs the pressure to the sub-ECU 32.

In addition, the first supply path 23 is connected to the third supply path 30. The third supply path 30 is connected to a pair of double check valves 36. One of the double check valves 36A is connected to the third supply path 30, the front signal supply path 24A and the front air supply path 37, the front signal supply path 24A is connected to the front pressure chamber 13A of the brake valve 13, and the front air supply path 37 is used to generate braking force on the front wheel. The double check valve 36A allows the supply of compressed air from the third supply path 30 and the front signal supply path 24A, which has a higher pressure, and cuts off the supply of compressed air from the lower pressure. The front air supply path 37 is connected to the second pressure sensor 39. The second pressure sensor 39 outputs the detected pressure to the sub-ECU 32. The pressure detected by the second pressure sensor 39 is the "supply pressure" supplied to the brake chamber 17.

Another double check valve 36B is connected to the third supply path 30, the rear signal supply path 24B, and the rear air supply path 38. The rear signal supply path 24B is connected to the rear pressure chamber 13B of the brake valve 13, and the rear air supply path 38 applies a braking force to the rear wheels. The double check valve 36B allows the supply of compressed air from the third supply path 30 and the rear signal supply path 24B with a higher pressure, and cuts off the supply of compressed air from the lower pressure. The pair of second ports P2 are respectively connected to the front signal supply path 24A and the rear signal supply path 24B.

Next, the operation of the pressure control module 20 will be described with reference to Fig. 4 and Fig. 5. Fig. 4 shows the air pressure circuit 22 when the driver seat operation switch 51 and the passenger seat operation switch 53 are not turned on.

As shown in FIG. 4 , when the driver's seat operation switch 51 and the passenger seat operation switch 53 are not turned on, the sub-ECU 32 sets the intake valve 27 and the exhaust valve 28 to non-driving. In this case, the intake valve 27 is in a closed position, and the exhaust valve 28 is in an open position. As a result, the portion of the branch path 26 downstream of the intake valve 27 becomes a prescribed pressure such as atmospheric pressure because the exhaust valve 28 is in an open position. Therefore, the air pressure applied to the pilot port 25B also becomes a prescribed pressure, so the relay valve 25 is in an exhaust state. When the relay valve 25 is in an exhaust state, the compressed air of the portion of the first supply path 23 downstream of the relay valve 25 and the third supply path 30 is discharged from the discharge portion 58, and the pressure of the third supply path 30 becomes a prescribed pressure. In addition, when the brake pedal 13C is stepped on, etc., an air pressure signal is supplied to the front signal supply path 24A and the rear signal supply path 24B. As a result, the pressure of the front signal supply path 24A and the rear signal supply path 24B becomes higher than the pressure of the third supply path 30, so the double check valves 36A and 36B cut off the air flow from the third supply path 30 to the front air supply path 37 and the rear air supply path 38, respectively. Then, an air pressure signal is supplied from the front signal supply path 24A to the front air supply path 37, and an air pressure signal is supplied from the rear signal supply path 24B to the rear air supply path 38. As a result, a large amount of compressed air is supplied from the air tank 12 to the relay valve 15 by supplying the air pressure signal to the relay valve 15. When the relay valve 15 supplies compressed air to the brake chamber 17, a braking force is applied to the wheel. In addition, the air pressure circuit including the front signal supply path 24A and the rear signal supply path 24B corresponds to a brake control circuit.

FIG. 5 shows the air pressure circuit 22 when at least one of the driver's seat operation switch 51 and the passenger seat operation switch 53 is turned on. When at least one of the driver's seat operation switch 51 and the passenger seat operation switch 53 is turned on, the sub-ECU 32 receives the pressure indication sent from the main ECU 31. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure indication. As a result, the intake valve 27 is in the open position and the exhaust valve 28 is in the closed position. The compressed air of the gas tank 12 is supplied to the branch path 26 between the intake valve 27 and the exhaust valve 28 via the first supply path 23. When the pressure of the branch path 26 between the intake valve 27 and the exhaust valve 28 reaches the driving pressure, the pressure is applied to the relay valve 25 via the pilot port 25B, and the relay valve 25 is in the supply state. As a result, the compressed air is supplied to the third supply path 30 via the first supply path 23 and the relay valve 25.

When compressed air is supplied to the third supply path 30, the pressure of the third supply path 30 becomes higher than the pressure of the front signal supply path 24A and the rear signal supply path 24B. Therefore, the double check valve 36 allows the airflow from the third supply path 30 to the front air supply path 37 and the rear air supply path 38, and cuts off the airflow from the front signal supply path 24A to the front air supply path 37 and the airflow from the rear signal supply path 24B to the rear air supply path 38. In addition, the air pressure circuit including the flow path (the first supply path 23, the branch path 26, etc.) connecting the intake valve 27, the exhaust valve 28 and the relay valve 25 and the third supply path 30 corresponds to the abnormal braking control circuit.

By providing the pressure control module 20 between the brake valve 13 and the relay valve 15 in this manner, when the driver's seat operating switch 51 and the passenger seat operating switch 53 are turned on, the air pressure driven command system is switched from the system via the brake valve 13 to the system directly supplying air from the air tank 12. Therefore, even if there is no air pressure signal input from the brake valve 13, the brake chamber 17 can be operated to generate a braking force.

In addition, the sub-ECU 32 obtains the detected pressure from the first pressure sensor 35 and the second pressure sensor 39 at a predetermined timing. For example, when the relay valve 25 is maintained in the supply state, the sub-ECU 32 sets the intake valve 27 and the exhaust valve 28 to be driven or non-driven so that the pressure detected by the first pressure sensor 35 is within a predetermined range. In addition, when the main ECU 31 sends a pressure instruction to the sub-ECU 32 so that the pressure is gradually increased to slowly stop the vehicle 10, the sub-ECU 32 determines whether the pressure detected by the second pressure sensor 39 has reached the first pressure threshold. When the sub-ECU 32 determines that the detected pressure has not reached the first pressure threshold, the intake valve 27 and the exhaust valve 28 are driven to maintain the relay valve 25 in the supply state. On the other hand, when the pressure detected by the second pressure sensor 39 has reached the first pressure threshold, the sub-ECU 32 sets the intake valve 27 and the exhaust valve 28 to be non-driven to set the relay valve 25 in the exhaust state. Then, the sub-ECU 32 waits for the next pressure instruction from the main ECU 31. Furthermore, the air pressure of the signal supply path 29 is controlled by the intake valve 27 and the exhaust valve 28 to drive the relay valve 25 , thereby supplying a desired air pressure to the third supply path 30 .

Next, the process of the abnormal response performed by the main ECU 31 is described with reference to FIGS. 6 to 8. The process shown in FIG. 6 is a process for controlling the air system, and it is assumed that the process is started when the driver's seat operation switch 51 or the passenger seat operation switch 53 is operated and the main ECU 31 inputs the operation signal sent from these switches. In addition, it is assumed that the main ECU 31 receives vehicle information from the acceleration sensor 54 and the vehicle speed sensor 55 at a predetermined timing. In FIG. 7, the solid line represents the speed V of the vehicle, the thick line represents the pressure Pa of the air supplied to the brake chamber 17, and the single-point chain line represents the deceleration a.

As shown in FIG6 and FIG7, when the operation signal is input at time t1, the main ECU 31 determines whether the passenger seat operation switch 53 is operated (step S1). That is, the main ECU 31 determines whether the input operation signal is a signal from the driver seat operation switch 51 or a signal from the passenger seat operation switch 53. Then, when the main ECU 31 determines that the driver seat operation switch 51 is operated (step S1: No), it transfers to step S4. Here, the stage until the time t1 when the passenger seat operation switch 53 is operated is referred to as the "system standby interval S0".

On the other hand, when the main ECU 31 determines that the passenger seat operation switch 53 has been operated (step S1: Yes), it instructs the sub-ECU 32 to apply the deceleration pressure Pa1 required for deceleration (step S2). Deceleration refers to braking with a small absolute value of deceleration or braking with a short time required for braking, and it is possible to return to normal driving when the release switch 52 is operated immediately afterwards. Then, the deceleration pressure is sent to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction, and supplies to the brake chamber 17 (refer to FIG. 5).

The main ECU 31 determines whether the slow braking time T1 has passed (step S3). That is, the main ECU 31 determines whether the slow braking time T1 has passed based on the time from the time when the pressure instruction is sent to the sub-ECU 32, the time when the vehicle 10 starts to decelerate, or the time when the sub-ECU 32 receives a predetermined response signal. The slow braking time T1 is the time required for the driver to operate the release switch 52 when the passenger seat operation switch 53 is erroneously operated even though the driver is in a normal state. Then, when the main ECU 31 determines that the slow braking time T1 has not passed (step S3: No), it instructs the sub-ECU 32 to apply the slow braking pressure Pa1 and continue the slow braking (step S2). Here, the stage from time t1 to time t2 when the slow braking time T1 has passed is set as the "attention-calling braking section Ph1".

On the other hand, when the main ECU 31 determines that the slow braking time has passed (step S3: Yes), it instructs the sub-ECU 32 to perform the main brake. The main brake refers to the brake that decelerates the vehicle 10 at a deceleration greater than the absolute value of the deceleration of the slow brake and finally stops the vehicle 10. The main ECU 31 obtains the target deceleration for the main brake stored in its own storage unit, and calculates the increase of the specified pressure ΔPa2 and the decrease of the specified pressure ΔPa4 by comparing with the deceleration obtained according to the acquired vehicle speed. Then, the calculated air pressure is sent to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction (refer to Figure 5). In addition, the following steps after step S4 are equivalent to the "deceleration step" of supplying air to the brake chamber 17 to decelerate the vehicle.

The main ECU 31 increases the supply pressure by increasing the predetermined pressure ΔPa2 every predetermined time ΔT2 (step S4). That is, the main ECU 31 determines the supply pressure every predetermined time ΔT2. The main ECU 31 sends the determined air pressure to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction sent from the main ECU 31, and supplies the brake chamber 17 in a manner that the determined target pressure is achieved.

Next, the main ECU 31 determines whether the supply pressure is above the upper limit pressure Pa3 (step S5). That is, the supply pressure increases due to the increase of the specified pressure ΔPa2, so the main ECU 31 determines whether the increased supply pressure is above the upper limit pressure Pa3. Then, when the main ECU 31 determines that the supply pressure is less than the upper limit pressure Pa3 (step S5: No), it transfers to step S4 to supply the supply pressure obtained by increasing the specified pressure ΔPa2 every specified time ΔT2. Here, the stage from time t2 to time t3 when the upper limit pressure Pa3 is reached is set as the "braking force generation interval Ph2". In addition, in non-patent document 1, an upper limit of the deceleration during emergency stop is set. When it is greater than the upper limit of the deceleration (for example, 2.45m/ss), it is necessary to exhaust the air so that the supply pressure is less than the upper limit pressure Pa3 or interrupt the deceleration.

On the other hand, when the main ECU 31 determines that the supply pressure is equal to or higher than the upper limit pressure Pa3 (step S5: Yes), the supply pressure is fixed to the upper limit pressure Pa3 (step S6). That is, the main ECU 31 fixes the supply pressure to the upper limit pressure Pa3 to make the braking force of the brake chamber 17 constant, thereby suppressing a sudden change in speed. The main ECU 31 sends the determined air pressure to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction sent from the main ECU 31, and supplies air to the brake chamber 17 in a manner that the determined target pressure is achieved.

Next, the main ECU 31 determines whether the speed of the vehicle is below the prescribed speed Vth (step S7). That is, the main ECU 31 determines whether the speed of the vehicle becomes below the prescribed speed Vth after being reduced by the braking of the brake chamber 17. The prescribed speed Vth is a speed at which the vehicle can be easily stopped in a short time, such as a low speed of 10 km to 20 km per hour, a speed immediately before stopping, or a lower limit value that can be measured by the vehicle speed sensor 55. Then, when the main ECU 31 determines that the speed of the vehicle is greater than the prescribed speed Vth (step S7: No), it instructs the sub-ECU 32 to set the upper limit pressure Pa3 and repeats the determination (step S7) until the speed of the vehicle becomes below the prescribed speed Vth. Here, the stage from time t3 to time t4 when the speed becomes below the prescribed speed Vth is set as the "fixed deceleration braking interval Ph3".

On the other hand, when the main ECU 31 determines that the speed of the vehicle is below the predetermined speed Vth (step S7: Yes), the main ECU 31 reduces the supplied air pressure by the predetermined pressure ΔPa4 every predetermined time ΔT4 (step S8). That is, the main ECU 31 determines the supply pressure every predetermined time ΔT4. The main ECU 31 sends the determined air pressure to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction sent from the main ECU 31, and supplies air to the brake chamber 17 in a manner that the determined target pressure is achieved. In addition, step S8 corresponds to the "air pressure reduction step" of reducing the air pressure supplied to the brake chamber 17 when the vehicle becomes below the predetermined speed Vth during deceleration.

Next, the main ECU 31 determines whether the supply pressure is less than the lower limit pressure Pa4 (step S9). That is, the supply pressure is reduced by reducing the prescribed pressure ΔPa4, so the main ECU 31 determines whether the reduced supply pressure is less than the lower limit pressure Pa4. If the main ECU 31 determines that the supply pressure is greater than the lower limit pressure Pa4 (step S9: No), it transfers to step S8 and supplies the supply in a manner that the prescribed pressure ΔPa4 is reduced every prescribed time ΔT4.

On the other hand, when the main ECU 31 determines that the supply pressure is less than the lower limit pressure Pa4 (step S9: Yes), the supply pressure is fixed to the lower limit pressure Pa4 (step S10). That is, the main ECU 31 fixes the supply pressure to the lower limit pressure Pa4 to make the braking force of the brake chamber 17 constant, thereby suppressing a sudden change in speed. The main ECU 31 sends the determined air pressure to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction sent from the main ECU 31, and supplies air to the brake chamber 17 in a manner that the determined target pressure is achieved.

Next, the main ECU 31 determines whether the stop determination time T4 has passed since the lower limit pressure Pa4 was set (step S11). That is, the main ECU 31 determines whether the stop determination time T4, which is the time required until the vehicle stops, has passed. Then, when the main ECU 31 determines that the stop determination time T4 has not passed (step S11: No), it instructs the sub-ECU 32 to set the lower limit pressure Pa4 and repeats the determination (step S11) before the stop determination time T4 passes. In addition, the stop determination time T4 is equivalent to a prescribed time. Here, the stage from time t4 to time t5 after the stop determination time T4 has passed after the lower limit pressure Pa4 is set from time t4 is set as the "braking force relaxation interval Ph4". In addition, the stage after time t5 is set as the "parking brake interval Ph5".

On the other hand, when the main ECU 31 determines that the stop determination time T4 has passed (step S11: Yes), the supply pressure is fixed to the stop pressure Pa5 (step S12). That is, the main ECU 31 increases the supply pressure from the lower limit pressure Pa4 to the stop pressure Pa5 and continues to supply the stop pressure Pa5 until the end. The main ECU 31 sends the determined air pressure to the sub-ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure instruction sent from the main ECU 31, and supplies the brake chamber 17 with the determined target pressure. In addition, the stop pressure Pa5 is equivalent to the specified value.

Next, the main ECU 31 determines whether the abnormal response is completed (step S13). The abnormal response can be determined to be completed when the vehicle 10 stops and the parking brake is in operation, or when the ignition switch is turned off, or at other timings. Then, if the main ECU 31 determines that the abnormal response is not completed (step S13: No), it instructs the sub-ECU 32 to stop the pressure Pa5 and continue the abnormal response (step S4). On the other hand, when the main ECU 31 determines that the abnormal response is completed (step S13: Yes), it ends the abnormal response process.

In addition, unlike the abnormal response of the air system, the main ECU 31 operates the in-vehicle device 56 and the out-vehicle device 57 at a predetermined timing such as the timing of starting the main brake. This can notify the occupants of the vehicle 10 of the abnormality and also can prompt the attention of other vehicles traveling around the vehicle 10.

Next, the procedure of the release process when the release switch 52 is operated will be described with reference to Fig. 8. It is assumed that the process shown in Fig. 8 is started when the driver's seat operation switch 51 or the passenger seat operation switch 53 is operated and the main ECU 31 inputs the operation signal.

As shown in FIG. 8 , the main ECU 31 determines whether the release switch 52 is operated (step S20). That is, the main ECU 31 determines whether an operation signal is input from the release switch 52. Then, when the main ECU 31 determines that the release switch 52 is operated (step S20: Yes), it sends a brake release instruction to the sub-ECU 32 (step S21). The sub-ECU 32 that receives the release instruction sets the intake valve 27 and the exhaust valve 28 to non-actuated states to cut off the supply of air from the air tank 12 to the brake chamber 17 side.

On the other hand, when the main ECU 31 determines that the release switch 52 is not operated (step S20: No), it determines whether the abnormality response is completed (step S22). Then, when the main ECU 31 determines that the abnormality response is not completed (step S22: No), it transfers to step S20. On the other hand, when the main ECU 31 determines that the abnormality response is completed (step S22: Yes), it ends the release process.

Next, the effects of this embodiment will be described.

(1) When the vehicle is decelerating and the speed is below the predetermined speed Vth, the air pressure supplied to the brake chamber 17 is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to come to a complete stop. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

(2) The vehicle stops after a predetermined time has passed since the lower limit pressure Pa4 was reached. Therefore, the air pressure supplied to the brake chamber 17 is increased to a stop pressure Pa5 or higher to increase the braking force of the brake chamber 17, thereby preventing the vehicle from moving from the stopped state.

(3) When the vehicle decelerates to a certain extent during deceleration, the air pressure supplied to the brake chamber 17 is fixed to the upper limit pressure Pa3, so that the braking force of the brake chamber 17 can be made constant, and a sudden change in the speed V of the vehicle can be suppressed.

(4) Since the air pressure supplied to the brake chamber 17 is determined at every predetermined time ΔT2 and every predetermined time ΔT4, the amount of calculation can be reduced compared to the case where the air pressure supplied to the brake chamber 17 is determined at any time.

(5) Normally, the brake valve supplies air to the brake chamber 17 according to the driver's brake operation. However, when the driver is abnormal, air is supplied to the brake chamber 17 by controlling the air pressure circuit instead of the brake valve, thereby enabling the vehicle to be stopped urgently.

(6) Since the occupant may panic if the vehicle is braked suddenly immediately after the occupant switch is operated, the occupant is firstly braked slowly by the brake chamber 17 to draw attention.

(7) The first communication state in which the brake valve is connected to the brake chamber 17 to supply air from the second port to the third port is switched to the second communication state in which the air tank is connected to the brake chamber 17 to supply air from the first port to the third port. Therefore, air can be automatically supplied from the air tank to the brake chamber 17 to generate braking force.

(Other embodiments)

The above-mentioned embodiment can be implemented by modification as follows. The above-mentioned embodiment and the following modification examples can be implemented in combination with each other within the range that there is no technical contradiction.

In the above embodiment, the predetermined time ΔT2 and the predetermined time ΔT4 may be the same or different.

In the above embodiment, the main ECU 31 determines the pressure supplied to the brake chamber 17 at every predetermined time ΔT2 and every predetermined time ΔT4. However, as shown in FIG9 , the main ECU 31 may perform calculations at any time to determine the pressure supplied to the brake chamber 17. In this way, the pressure supplied to the brake chamber 17 can be accurately determined according to the speed of the vehicle to perform braking.

In the above embodiment, it is determined whether the stop determination time T4 has passed since the lower limit pressure Pa4 has been reached. However, it may be determined whether the stop determination time has passed since the predetermined speed Vth has been reached. According to such a configuration, the vehicle stops after the stop determination time T4 has passed since the predetermined speed Vth has been reached or lower. Therefore, the air pressure supplied to the brake chamber 17 is increased to a stop pressure Pa5 or higher to increase the braking force of the brake chamber 17, thereby preventing the vehicle from moving from a stopped state.

In the above embodiment, after the stop determination time T4 has elapsed, the stop pressure Pa5 is fixed. However, the parking brake or the electric parking brake may be actuated to maintain the vehicle in a stopped state.

In the above embodiment, when the passenger seat operation switch 53 is operated, the braking pressure Pa1 is supplied to the brake chamber 17 during the braking time T1. However, the braking time T1 may be set as the attention calling time, and no pressure may be supplied to the brake chamber 17.

In the above embodiment, the air pressure control device and the air pressure circuit are applied to the vehicle 10 with full air brake. Not limited to this, the air pressure control device and the air pressure circuit can also be applied to vehicles with other forms of brake systems. As shown in FIG. 10, the pressure control module 20 can be applied to the vehicle 10 with an air-over-hydraulic brake mechanism. In this brake mechanism, the pressure control module 20 is connected to the brake boosters 100 to 102 via the ABS control valve 16. The brake boosters 100 to 102 are boosters for the front wheels, the rear left wheels, and the rear right wheels, and use air pressure to increase the hydraulic pressure of the hydraulic circuit, thereby generating braking force on the wheels. In addition, as shown in FIG. 11, the pressure control module 20 can also be applied to a brake mechanism having a brake booster 103 for the front wheels, a brake booster 104 for the rear wheels, and an ABS control valve 105 provided in the hydraulic circuit. Alternatively, the air pressure control device and the air pressure circuit can also be applied to brake mechanisms other than those shown in FIG. 10 and FIG. 11.

In the above embodiment, the main body 211 is made of metal, but it may be formed of resin instead. For example, the main body 211 is formed by casting, but it may be formed by combining components formed by stamping or cutting instead of or in addition to this.

In the above embodiment, the gas tank 12 is divided into three gas tanks, but the gas tank 12 may be one gas tank, or two, or four or more gas tanks. In addition, the connection relationship between the gas tank 12 and the air pressure device may be appropriately changed. For example, the first port P1 of the pressure control module 20 may also be connected to a gas tank other than the third gas tank 12C.

In the above embodiment, the main ECU 31 may receive an on signal from the driver's seat operation switch 51, the release switch 52, and the passenger seat operation switch 53 via an in-vehicle network such as the CAN 33. In addition to the CAN 33, the in-vehicle network may use a network such as FlexRay (registered trademark) or Ethernet (registered trademark).

In the above embodiment, the main ECU 31 obtains acceleration information from the acceleration sensor 54, but instead, the main ECU 31 may obtain acceleration information from the vehicle speed sensor 55. In addition, acceleration is also included in the "vehicle speed" in the claims.

In the above embodiment, the abnormality response system 50 includes the main ECU 31 and the sub-ECU 32. Alternatively or in addition thereto, the main ECU 31 and the sub-ECU 32 may be formed by one ECU or other control circuit having the functions of the first control unit and the second control unit. Alternatively, these functions may be distributed to three or more ECUs or other control circuits.

In the above embodiment, the abnormality response system 50 may also include a main switch (not shown) that can turn on/off the functions of the system. By performing a predetermined operation on the main switch or controlling the main switch by a predetermined control device, for example, the operation of the driver's seat operation switch 51, the release switch 52, and the passenger seat operation switch 53 can be invalidated.

In the above embodiment, the air pressure circuit 22 drives the air pressure driven relay valve 25 via the intake valve 27 and the exhaust valve 28. Alternatively, a solenoid valve may be provided in the first supply path 23 to open and close the first supply path 23.

In the above embodiment, the relay valve 25 may be omitted and the signal supply path 29 may be directly connected to the third supply path. Even with such a configuration, the air pressure of the signal supply path 29 may be controlled by the intake valve 27 and the exhaust valve 28 to supply the third supply path 30 with a desired air pressure.

In the above embodiment, the air pressure circuit 22 is provided with a double check valve 36 for switching the air supply direction by air pressure. Instead of the double check valve 36, a solenoid valve that is driven and non-driven by the sub-ECU 32 may be provided. When the driver's seat operation switch 51 or the passenger seat operation switch 53 is turned on, the sub-ECU 32 drives (or does not drive) the solenoid valve to switch the air supply direction.

In the above embodiment, the configuration of the first pressure sensor 35 may be omitted. In this case, the sub-ECU 32 performs control using the pressure detected by the second pressure sensor 39 instead of using the pressure detected by the first pressure sensor 35 .

In the above-mentioned embodiment, the abnormal response is performed according to the on operation of the driver's seat operation switch 51 and the passenger seat operation switch 53. Instead of or in addition to this, a biological detection device that detects the fatigue state or health state of the driver may be used. The biological detection device uses one or more parameters such as the position and posture of the driver's face or head, the state of the eyes such as eyelids or sight, pulse rate, heart rate, body temperature, etc. to detect the driver's state. In this method, an abnormal signal is sent when the biological detection device detects that the driver is abnormal. Alternatively, the ECU mounted on the vehicle may compare the vehicle state such as the operation of the vehicle speed, accelerator pedal or brake pedal with the road information, and send an abnormal signal when abnormal driving is detected.

In the above embodiment, the air pressure control device is installed in an existing vehicle in which the brake command system is an air pressure circuit. However, the air pressure control device may be installed in a vehicle equipped with EBS in an after-sales manner. In addition, the air pressure control device may be installed in a new vehicle.

In the above embodiment, the air pressure control device is described as being mounted on a vehicle such as a bus. In addition to the bus, the vehicle may be a truck, a construction machine, etc. In addition, as another embodiment, the air pressure control device may be mounted on other vehicles such as a passenger car and a railway vehicle.

· Driver abnormality may also occur in new vehicles or used vehicles that control the brake mechanism through a hydraulic circuit, so the same problem exists. Therefore, the pressure control module 20 of the above embodiment can also be applied to vehicles that implement a command system that sends commands to the brake mechanism through hydraulic pressure. In the hydraulic circuit as well, the pressure control module 20 works in the same way as the above embodiment. In this method, the brake mechanism that is the control object can also be a mechanism other than the brake chamber. In addition, the hydraulic circuit and the air pressure circuit are examples of circuits that are driven by the pressure of the fluid.

The present invention can also be applied to hydraulic brakes, not limited to air pressure brakes.

According to one embodiment of the present hydraulic brake, a hydraulic control device is provided. The hydraulic control device comprises: a hydraulic circuit configured to supply oil to a brake mechanism for applying braking force to wheels; and a control unit configured to control the hydraulic pressure supplied from the hydraulic circuit to the brake mechanism, wherein the control unit is configured to supply oil to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle, and to reduce the hydraulic pressure supplied to the brake mechanism when the vehicle reaches a predetermined speed or less.

According to the above structure, when the vehicle is decelerating and the speed is below the specified speed, the hydraulic pressure supplied to the brake mechanism is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

In the above-mentioned hydraulic control device, the control unit may be configured to increase the reduced hydraulic pressure to a predetermined value or more after a predetermined time has elapsed since the vehicle speed has reached or decreased to the predetermined speed or less.

According to the above configuration, the vehicle stops after a predetermined time has passed since the vehicle speed fell below a predetermined speed. Therefore, the hydraulic pressure supplied to the brake mechanism is increased to a predetermined value or more to increase the braking force of the brake mechanism, thereby preventing the vehicle from moving from the stopped state.

In the above-mentioned hydraulic control device, the control unit may be configured to increase the hydraulic pressure supplied to the brake mechanism to a predetermined value or more after a predetermined time has passed since the hydraulic pressure became equal to or less than a lower limit pressure due to the pressure reduction.

According to the above configuration, the vehicle stops after a predetermined time has passed since the pressure fell below the lower limit. Therefore, the hydraulic pressure supplied to the brake mechanism is increased to a predetermined value or more to increase the braking force of the brake mechanism, thereby preventing the vehicle from moving from the stopped state.

In the above-mentioned hydraulic control device, the control unit may be configured to fix the hydraulic pressure supplied to the brake mechanism to the upper limit pressure when the hydraulic pressure supplied to the brake mechanism becomes equal to or higher than an upper limit pressure during deceleration of the vehicle.

According to the above configuration, when the vehicle is decelerated to a certain extent during deceleration, the hydraulic pressure supplied to the brake mechanism is made constant, so that the braking force of the brake mechanism can be made constant, thereby suppressing a sudden change in speed.

In the above-mentioned hydraulic pressure control device, the control unit may be configured to determine the hydraulic pressure supplied to the brake mechanism at predetermined time intervals.

According to the above configuration, the hydraulic pressure supplied to the brake mechanism is determined at predetermined time intervals, so the amount of calculation can be reduced compared to a case where the hydraulic pressure supplied to the brake mechanism is determined at any time.

In the above-mentioned hydraulic control device, the hydraulic circuit may be configured to supply oil to the brake mechanism instead of a brake valve that supplies oil to the brake mechanism when a brake operation is performed.

According to the above configuration, the brake valve normally supplies oil to the brake mechanism according to the driver's brake operation. However, when the driver is abnormal, the control unit controls the hydraulic circuit to supply oil to the brake mechanism instead of the brake valve, thereby enabling the vehicle to be stopped urgently.

The hydraulic control device may be configured such that, when an abnormality signal indicating an abnormality based on the operation of the passenger switch is obtained as a signal for causing the vehicle to stop urgently, the control unit supplies hydraulic pressure for slow braking to the brake mechanism. According to the above structure, if the emergency braking is performed immediately after the operation of the passenger switch, the passenger panics, and therefore, the attention can be called by first causing the brake mechanism to perform slow braking.

According to one embodiment of the present hydraulic brake, a hydraulic control method of a hydraulic control device is provided. The hydraulic control device comprises: a hydraulic circuit configured to supply oil to a brake mechanism for applying braking force to a wheel; and a control unit configured to control the hydraulic pressure supplied from the hydraulic circuit to the brake mechanism. The hydraulic control method comprises: a deceleration step of supplying oil to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle; and a hydraulic pressure reduction step of reducing the hydraulic pressure supplied to the brake mechanism when the vehicle becomes below a predetermined speed during the deceleration.

According to the above method, when the vehicle is decelerating and the speed is below the specified speed, the hydraulic pressure supplied to the brake mechanism is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

According to one embodiment of the hydraulic brake, a hydraulic control program of a hydraulic control device is provided. The hydraulic control device comprises: a hydraulic circuit configured to supply oil to a brake mechanism for applying braking force to wheels; and a control unit configured to control the hydraulic pressure supplied from the hydraulic circuit to the brake mechanism. When the hydraulic control program is executed in a computer of the hydraulic control device, the hydraulic control device executes: a deceleration step of supplying oil to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle; and a hydraulic pressure reduction step of reducing the hydraulic pressure supplied to the brake mechanism when the vehicle becomes below a predetermined speed during the deceleration.

According to the above program, when the vehicle is decelerating and the speed is below the specified speed, the hydraulic pressure supplied to the brake mechanism is reduced to weaken the braking force, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

According to one embodiment of the hydraulic brake, a non-transitory computer-readable medium for storing a hydraulic control program is provided. When the hydraulic control program is executed in a computer of a hydraulic control device, the hydraulic control device executes a deceleration step and a hydraulic pressure reduction step. The hydraulic control device comprises: a hydraulic circuit configured to supply oil to a brake mechanism for applying a braking force to a wheel; and a control unit configured to control the hydraulic pressure supplied from the hydraulic circuit to the brake mechanism, wherein in the deceleration step, the vehicle is decelerated by supplying oil to the brake mechanism based on a signal for emergency stopping the vehicle, and in the hydraulic pressure reduction step, the hydraulic pressure supplied to the brake mechanism is reduced when the vehicle becomes below a predetermined speed during the deceleration.

The present invention can also be applied to an electric brake.

According to one embodiment of the electric brake, an electric control device is provided. The electric control device comprises: an electric circuit configured to supply electric power to a brake mechanism for providing a braking force to a wheel; and a control unit configured to control the electric power supplied from the electric circuit to the brake mechanism, wherein the control unit is configured to supply electric power to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle, and to supply electric power to the brake mechanism to decelerate the vehicle slowly when the vehicle reaches a predetermined speed or less.

According to the above structure, when the vehicle is decelerating and the speed is below the specified speed, the braking force is weakened by supplying power to the brake mechanism, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

In the electric control device described above, the control unit may be configured to increase the reduced-pressure supply power to a predetermined value or more after a predetermined time has elapsed since the vehicle speed reaches or falls below the predetermined speed.

According to the above configuration, the vehicle stops after a predetermined time has passed since the vehicle speed reaches a predetermined speed or less. Therefore, the braking force of the braking mechanism is increased by increasing the power supplied to the braking mechanism to a predetermined value or more, thereby preventing the vehicle from moving from the stopped state.

In the above-mentioned electric control device, the control unit may be configured to increase the electric power supplied to the brake mechanism to a predetermined value or more after a predetermined time has passed since the braking force becomes equal to or less than a lower limit value due to the deceleration.

According to the above configuration, the vehicle stops after a predetermined time has passed since the lower limit value has been reached. Therefore, the braking force of the braking mechanism is increased by increasing the power supplied to the braking mechanism to a predetermined value or more, thereby preventing the vehicle from moving from the stopped state.

In the above-mentioned electric control device, the control unit may be configured to fix the braking force of the braking mechanism to the upper limit value when the braking force of the braking mechanism becomes equal to or greater than an upper limit value during deceleration of the vehicle.

According to the above configuration, the braking force of the braking mechanism can be made constant at the point in time when the vehicle is decelerated to a certain extent during deceleration, thereby suppressing a rapid change in speed.

In the above-mentioned electric control device, the control unit may be configured to determine the electric power to be supplied to the brake mechanism at predetermined time intervals.

According to the above configuration, the electric power to be supplied to the brake mechanism is determined at predetermined time intervals. Therefore, the amount of calculation can be reduced compared to a case where the electric power to be supplied to the brake mechanism is determined at any time.

The electric control device may be configured such that, when an abnormality signal indicating an abnormality based on the operation of the passenger switch is obtained as a signal for causing the vehicle to stop urgently, the control unit supplies power for slow braking to the brake mechanism. According to the above structure, if the emergency brake is immediately applied after the operation of the passenger switch, the passenger panics, and therefore, attention can be called by first applying slow braking to the brake mechanism.

According to one embodiment of the present electric brake, an electric control method of an electric control device is provided. The electric control device comprises: an electric circuit configured to supply electric power to a brake mechanism for providing a braking force to a wheel; and a control unit configured to control the electric power supplied from the electric circuit to the brake mechanism. The electric control method comprises: a deceleration step of supplying electric power to the brake mechanism to decelerate the vehicle based on a signal for emergency stopping the vehicle; and a slow braking step of controlling the electric power supplied to the brake mechanism to perform slow braking when the vehicle becomes below a predetermined speed during the deceleration.

According to the above method, when the vehicle is decelerating and the speed is below the specified speed, the braking force is weakened by controlling the power supplied to the brake mechanism, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

According to one embodiment of the electric brake, an electric control program of an electric control device is provided. The electric control device comprises: an electric circuit configured to supply electric power to a brake mechanism for providing a braking force to a wheel; and a control unit configured to control the electric power supplied from the electric circuit to the brake mechanism. When the electric control program is executed in a computer of the electric control device, the electric control device executes: a deceleration step of supplying electric power to the brake mechanism based on a signal for emergency stopping the vehicle to decelerate the vehicle; and a slow braking step of controlling the electric power supplied to the brake mechanism to perform slow braking when the vehicle becomes less than a specified speed during the deceleration.

According to the above program, when the vehicle is decelerating and the speed is below the specified speed, the braking force is weakened by reducing the power supplied to the brake mechanism, thereby reducing the acceleration change (jerk) at the moment when the vehicle is about to stop completely. Therefore, the load applied to the occupants when the vehicle stops suddenly can be suppressed.

According to one embodiment of the electric brake, a non-transitory computer-readable medium storing an electric control program is provided. When the electric control program is executed in a computer of an electric control device, the electric control device executes a deceleration step and a slow braking step. The electric control device comprises: an electric circuit configured to supply power to a braking mechanism for applying braking force to a wheel; and a control unit configured to control the power supplied from the electric circuit to the braking mechanism, wherein in the deceleration step, the vehicle is decelerated by supplying power to the braking mechanism based on a signal for emergency stopping the vehicle, and in the slow braking step, the power supplied to the braking mechanism is controlled to perform slow braking when the vehicle becomes less than a specified speed during the deceleration.

Description of Reference Numerals

10: vehicle; 11: air pressure brake system; 12: air tank; 13: brake valve; 13A: front pressure chamber; 13B: rear pressure chamber; 13C: brake pedal; 14A: protection valve; 14B: air horn device; 15: relay valve; 16: ABS control valve; 17: brake chamber; 18: air piping; 20: pressure control module; 21: housing; 21A: port connection; 21D: protrusion; 22: air pressure circuit; 23: first supply path; 24A: front signal supply path; 24B: rear signal supply path; 25: relay valve; 25A: exhaust port; 25B: pilot port; 26: branch path; 27: intake valve; 27A: wiring; 28: exhaust valve; 28A: wiring Line; 29: signal supply path; 30: third supply path; 31: main ECU; 32: sub-ECU; 33: CAN; 35: first pressure sensor; 36, 36A, 36B: double check valves; 37: front air supply path; 38: rear air supply path; 39: second pressure sensor; 39: pressure sensor; 50: abnormal response system; 51: driver's seat operation switch; 52: release switch; 53: passenger seat operation switch; 54: acceleration sensor; 55: vehicle speed sensor; 56: in-cabin device; 57: out-cabin device; 58: discharge part; 100~104: brake booster; 105: ABS control valve; P1: first port; P2: second port; P3: third port.

Claims (11)

1. An air pressure control device is provided with:

An air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and

A control unit configured to control an air pressure supplied from the air pressure circuit to the brake mechanism,

Wherein the control unit is configured to supply air to the brake mechanism based on a signal for causing the vehicle to come to an emergency stop, to perform:

Transmitting an instruction to supply air pressure forming a slow brake with a deceleration other than zero to the brake mechanism so that deceleration of the vehicle is performed by the slow brake,

When a predetermined slow brake time elapses after an instruction to supply air pressure for forming the slow brake is issued, the predetermined pressure is increased every predetermined time to supply air pressure for forming a main brake having a larger absolute value of deceleration than the slow brake to the brake mechanism so that deceleration of the vehicle is performed by the main brake,

When the vehicle is at or below a predetermined speed, the pressure of the air supplied to the brake mechanism is reduced,

When a signal for releasing the emergency stop is input during the slow braking, the vehicle is returned to normal running.

2. The air pressure control device according to claim 1, wherein,

The control unit is configured to increase the depressurized air pressure to a predetermined value or more after a predetermined time elapses from when the vehicle becomes equal to or lower than the predetermined speed.

3. The air pressure control device according to claim 1, wherein,

The control unit is configured to increase the air pressure supplied to the brake mechanism to a predetermined value or more after a predetermined time has elapsed since the air pressure has been reduced to a lower limit pressure or less by the pressure reduction.

4. An air pressure control device according to any one of claims 1 to 3, wherein,

The control unit is configured to fix the air pressure supplied to the brake mechanism to an upper limit pressure when the air pressure supplied to the brake mechanism becomes the upper limit pressure or higher during deceleration of the vehicle.

5. An air pressure control device according to any one of claims 1 to 3, wherein,

The control unit is configured to determine the air pressure to be supplied to the brake mechanism at predetermined intervals.

6. An air pressure control device according to any one of claims 1 to 3, wherein,

The air pressure circuit is configured to supply air to the brake mechanism instead of the brake valve that supplies air to the brake mechanism when a brake operation is performed.

7. An air pressure control device according to any one of claims 1 to 3, wherein,

The control unit is configured to supply air pressure forming a slow brake to the brake mechanism when an abnormality signal indicating abnormality based on an operation of an occupant switch is acquired as a signal for emergency stopping of the vehicle.

8. An air pressure control device according to any one of claims 1 to 3, wherein,

The air pressure circuit is configured to: has a first port connected to a gas tank of a vehicle, a second port connected to a brake valve that outputs an air pressure signal when a brake operation is performed, and a third port connected to a brake mechanism that applies a braking force to wheels based on the air pressure signal, switches between a first communication state in which air is supplied from the second port to the third port and a second communication state in which air is supplied from the first port to the third port,

The control unit is configured to switch the air pressure circuit from the first communication state to the second communication state based on a signal for causing an emergency stop of the vehicle.

9. An air pressure control method for an air pressure control device, the air pressure control device comprising: an air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and a control unit configured to control an air pressure supplied from the air pressure circuit to the brake mechanism, the air pressure control method including:

A deceleration step of supplying air to the brake mechanism based on a signal for stopping the vehicle in an emergency, the following processing being performed: transmitting an instruction to supply air pressure forming a slow brake with a deceleration different from zero to the brake mechanism so that the vehicle is decelerated by the slow brake, and when a predetermined slow brake time elapses after the instruction to supply air pressure forming the slow brake is transmitted, increasing the predetermined pressure every predetermined time to supply air pressure forming a main brake with a deceleration larger than the slow brake in absolute value to the brake mechanism so that the vehicle is decelerated by the main brake; and

An air pressure reducing step of reducing the air pressure supplied to the brake mechanism when the vehicle becomes equal to or lower than a predetermined speed during the deceleration period,

In the decelerating step, when a signal for releasing the emergency stop is input during the slow braking, the vehicle is returned to normal running.

10. A computer program product including an air pressure control program that, when executed by a computer of an air pressure control device, causes the air pressure control device to execute a deceleration step and an air pressure reduction step, the air pressure control device comprising: an air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and a control unit configured to control air pressure supplied from the air pressure circuit to the brake mechanism,

In the decelerating step, air is supplied to the brake mechanism based on a signal for making the vehicle come to an emergency stop to perform the following process: transmitting an instruction to supply air pressure forming a slow brake with a deceleration other than zero to the brake mechanism so that the vehicle is decelerated by the slow brake, increasing a predetermined pressure every predetermined time when a predetermined slow brake time elapses after the instruction to supply air pressure forming the slow brake is transmitted so that air pressure forming a main brake with a deceleration larger than the slow brake in absolute value is supplied to the brake mechanism so that the vehicle is decelerated by the main brake,

In the air pressure reducing step, the air pressure supplied to the brake mechanism is reduced when the vehicle becomes equal to or lower than a predetermined speed during the deceleration,

In the decelerating step, when a signal for releasing the emergency stop is input during the slow braking, the vehicle is returned to normal running.

11. A computer-readable medium storing an air pressure control program that, when operated by a computer of an air pressure control device, causes the air pressure control device to execute a deceleration step and an air pressure reduction step, the air pressure control device comprising: an air pressure circuit configured to supply air to a brake mechanism for providing braking force to wheels; and a control unit configured to control air pressure supplied from the air pressure circuit to the brake mechanism,

In the decelerating step, air is supplied to the brake mechanism based on a signal for making the vehicle come to an emergency stop to perform the following process: transmitting an instruction to supply air pressure forming a slow brake with a deceleration other than zero to the brake mechanism so that the vehicle is decelerated by the slow brake, increasing a predetermined pressure every predetermined time when a predetermined slow brake time elapses after the instruction to supply air pressure forming the slow brake is transmitted so that air pressure forming a main brake with a deceleration larger than the slow brake in absolute value is supplied to the brake mechanism so that the vehicle is decelerated by the main brake,

In the air pressure reducing step, the air pressure supplied to the brake mechanism is reduced when the vehicle becomes equal to or lower than a predetermined speed during the deceleration,

In the decelerating step, when a signal for releasing the emergency stop is input during the slow braking, the vehicle is returned to normal running.